Category Archives: Global

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Save Energy Now Program Enters Its Third Year

The Department of Energy’s (DOE’s) Industrial Technology Program’s (ITP’s) Save Energy Now (SEN) initiative is kicking off its third year. This program has been extremely successful in helping U.S. businesses, factories, and manufacturing facilities save both energy and money despite variable energy costs.

According to “Overview of the Save Energy Now Assessment Program,” a presentation given by Bob Gemmer, ITP technology manager, at the BestPractices Steam Steering Meeting on November 16, 2007, the SEN energy assessments build on existing resources, including the following:

  • Established training programs on software tools
  • A cadre of qualified specialists in various assessment tools and systems
  • A network of university-based Industrial Assessment Centers (IACs)
  • In-depth experience in conducting plant energy assessments using tools from the DOE
  • Internet information resources
  • The Energy Efficiency and Renewable Energy (EERE) information center (877-337-3463)

The SEN program conducts Energy Saving Assessments (ESAs) of the most energy-intensive U.S. plants. It works with partners to create awareness and find energy-saving solutions. It also disseminates energy-saving information and tools to 50,000 plants to help reduce natural gas and electricity use.

The goals of the SEN program are to encourage industry to voluntarily reduce its energy usage in a period of tight supplies by working with the largest, most energy-intensive plants in the United States, and to create momentum to significantly improve energy efficiency practices throughout the manufacturing sector. Participating plants are selected by the DOE based on several factors, including the plant’s energy consumption and the company’s intention to include other similar plants within the company.

Assessment experts spend 3 days at each facility. The first day includes the following activities:

  • Safety briefing and tour of the plant
  • Overview of user-friendly DOE tool to plant personnel
  • Agreement on potential energy efficiency opportunities to investigate
  • Initiation of data collection for potential opportunities

The second day’s activities include the following:

  • Continuation of data collection
  • Applying the DOE tool to quantify potential opportunities
  • Agreement between the plant lead and expert on opportunity results

The third day’s activities include the following:

  • Wrapping up tool analyses
  • Plant lead and expert ensure they agree on opportunity results
  • Close-out meeting held in the after-noon to review results

New for 2008

This year, group applications have been discontinued, simplifying the application process for the SEN program. According to www1.eere.energy.gov/industry/saveenergynow/application.html, smaller facilities can qualify on their own, as the awards will be based on applications received. Also, natural gas use will be given additional consideration in the selection process. Third parties may apply on behalf of a plant or company.

In addition, cost-sharing will be required for any facility that has received an energy assessment in one of the process areas in any preceding year. All other assessments will be at no cost to the plant. Cost-sharing may come from any source outside the DOE. In all cost-share cases, the DOE will provide payment for up to 22.5 hours of the 45 hours usually required for the energy expert to complete the energy assessment, and for the expert’s travel and lodging expenses. Negotiating the balance of the payment to the expert will be the responsibility of the applicant or a third party. The average cost to a company for its portion of a cost-shared assessment is estimated to be $3,000; however, this figure could be higher or lower, depending on the expert assigned.

Energy Assessment Options

In 2008, there is a lower threshold to qualify, with more midsize plants receiving assessments. According to www1.eere.energy.gov/industry/saveenergynow/assessments.html, the following options, based on plant size, are available for SEN energy assessments from the DOE:

  • For large plants: The nation’s largest, most energy-intensive plants can apply to receive the 3-day system assessment. These on-site assessments are led by the DOE’s energy experts who use the DOE’s software tools and technical information to target a specific system area. Assessments also provide valuable hands-on learning that can help a facility’s staff gain knowledge to multiply the benefits of the assessment.
  • For small and medium-size plants: The DOE’s university-based Industrial Assessment Centers (IACs) conduct 1-day assessments at smaller plants. Teams of trained IAC faculty and engineering students apply the same DOE software tools and technical resources to identify savings opportunities through-out each plant.
  • For all plants: Whether or not a facility receives an energy assessment, expert technical assistance and guidance on how to make the most of SEN resources are available at www1.eere.energy.gov/industry/bestpractices/info_center.html. According to Gemmer’s presentation, plants that apply but do not meet the criteria for an ESA can take advantage of personalized phone consultation to address energy efficiency in the plant; self-assessment tools; and products, DOE software tools, and training.

Why Save Energy Now?

According to “Overcoming Impediments to Investment in Process Heating Equipment,” a presentation given by Christopher Russell, principal at South River Facility Solutions, at the BestPractices Steam Steering Meeting on November 16, 2007, the energy paradigm for the 21st century includes the following factors:

  • Fuel and power markets are volatile.
  • Energy is a trackable, controllable expense.
  • Energy best practices are published and replicable.
  • Solutions involve technology, procedures, and behavior.
  • Energy cost control is a process, not a “project.”
  • Energy issues require a risk-management strategy.
  • Energy is wealth. It can be invested, preserved, and leveraged.

In the last 2 years, hundreds of companies have benefited from the SEN energy assessment program, and now states are allowed to participate (see page 43). On average, each large plant assessment yields a potential savings of $2.5 million. Implementing the recommended energy-saving measures can help participating facilities save 10 percent of more per year on energy bills, not to mention improving productivity and reducing greenhouse gas emissions.

To be eligible for a Save Energy Now energy assessment, applicants must complete an online application form. Please visit www1.eere.energy.gov/industry/saveenergynow/apply.html to begin the SEN application process today.*

* The DOE began making initial selections of applications for assessments starting in mid-September 2007. However, additional selections will be announced periodically until the target of 250 assessments is reached for the calendar year 2008.

NIA Sites > Insulation Outlook Magazine > Global

Introducing Mechanical Insulation Design Guide (MIDG)

After 2 years in development with contributions from 15 organizations, 60 manufacturers and fabricators, and 12 contractors, as well as the involvement of more than 100 individuals, The National Institute of Building Sciences (NIBS) and The National Insulation Association (NIA) have introduced the Mechanical Insulation Design Guide (MIDG). The MIDG is intended to be an unbiased, comprehensive, living document and vertical portal resource to assist specifiers, facility owners, and other users of mechanical insulation systems for a wide range of industrial and commercial applications.

Background

Mechanical insulation for commercial building and industrial applications is important to facility operations and manufacturing processes, yet it is often overlooked and undervalued. National standards, universal energy policies, and even generally accepted recommendations for what should be insulated, what insulation systems are acceptable for a specific use, and application best practices do not currently exist.

Development of mechanical insulation specifications and the selection of an insulation system are normally influenced by past practices or by the most knowledgeable person in the decision chain or industry segment included in the design-selection process.

Past Practices and Knowledge?

The topic of whether to depend on past practices or a knowledgeable resource produces many fundamental questions. For example, if relying on past practices, did those practices lead to a successful insulation system? Did the system perform to expectations? Were conditions like the cost of energy different 5, 10, or 20 years ago versus today? Are there new technologies or approaches that should be considered? Where can someone obtain unbiased information on what should be considered in designing, selecting, specifying, installing, and maintaining an insulation system?

If depending on a specific knowledge source, where is that source? Many—maybe most—engineering and architectural courses contain maybe 1 hour, if that, on mechanical insulation. The knowledge base in many engineering, architectural, and facility owner firms has eroded due to attrition, right sizing, and multitasking. In addition, the insulation manufacturers who for years were the educators of the industry have, for a multitude of reasons, dramatically reduced their in-person communication and education efforts.

Combine all of these factors, and you find the value of mechanical insulation is not being realized to its potential in reducing U.S. dependency on foreign energy sources, improving the environment, improving U.S. global competitiveness, and providing a safer work environment.

Mechanical insulation is applied but rarely “engineered.” With the best intentions, but not necessarily with thorough knowledge, many specifications have evolved primarily based upon modification of old documents. This practice has occurred along with a lack of mechanical insulation educational and awareness programs as to the value in having a properly engineered, installed, and maintained mechanical insulation system. This has led to the underutilization of mechanical insulation in energy conservation, emission reduction, process and productivity improvement, life-cycle cost reduction, personnel safety, and workplace improvement applications.

It is not like there are no mechanical insulation resources available. Several excellent guide specifications, handbooks, standards, and practices have been available for years. The effective use of those resources, however, is based on the premise that the user has access to them and has some level of knowledge about mechanical insulation. That assumption may not always be correct.

In response to the need for this information, the National Institute of Building Sciences (NIBS) in June 2005 formed the National Mechanical Insulation Committee (NMIC) for Building and Industrial Applications. This committee was created to bring together major governmental agencies, private industry, and organizations that are concerned with the design, installation, and maintenance of mechanical insulation systems. NIBS and NMIC offer the opportunity for a constructive public and private partnership in the examination of topics related to mechanical insulation. This committee will also provide education as to its findings regarding the value of properly engineering, applying, and maintaining mechanical insulation systems.

The National Institute of Building Sciences (NIBS), which is headquartered in Washington, D.C., was authorized by the U.S. Congress in the Housing and Community Development Act of 1974. In establishing NIBS, Congress recognized the need for an organization that could serve as an interface between government and the private sector. The institute’s public interest mission is to improve the building regulatory environment; facilitate the introduction of new and existing products and technology into the building process; and disseminate nationally recognized technical and regulatory information.

NIBS is a non-profit, non-government organization that brings together representatives of government, the professions, industry, labor, and consumer interests to focus on the identification and resolution of problems and potential problems that hamper the safe, affordable structures for housing, commerce, and industry throughout the United States. NIBS operates with a balanced blend of public and private funding and representation. This approach has enabled NIBS to bring together the nation’s finest expertise available from the public and private sectors to identify and resolve issues affecting the building process, and assure that no single interest area will dominate or hold undue influence over NIBS and its work. It also ensures both the maintenance and free exchange of information.

In early 2005, Marc LaFrance, technology development manager for the Buildings Technology Program at the Department of Energy (DOE), asked Earl Kennett, vice president of NIBS, to meet with the National Insulation Association (NIA) to explore avenues that could enhance the use of mechanical insulation in the commercial building and industrial sectors for energy conservation and the reduction of greenhouse gas emissions. That led to the development of the NMIC.

National Mechanical Insulation Committee (NMIC)

Individuals from the following government agencies and industry associations worked together in the development of the MIDG, with funding being shared between government agencies through NIBS and industry through NIA’s Foundation for Education, Training and Industry Advancement:

  • American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)
  • Architectural Computer Services, Inc. (ARCOM-Masterspec)
  • General Services Administration (GSA)
  • Midwest Insulation Contractors Association (MICA)
  • National Institute of Building Sciences (NIBS)
  • National Insulation Association (NIA)
  • North American Insulation Manufacturers Association (NAIMA)
  • Oak Ridge National Laboratory (ORNL)
  • United States Army Corps of Engineers (USACE)
  • United States Department of Energy (DOE)
  • United States Department of Veterans Affairs (VA)
  • United States Naval Facilities Engineering Command (NAVFAC)

The objective of NMIC is to identify, develop, and disseminate information related to mechanical insulation in commercial building and industrial applications by:

  • examining current policies, procedures, and practices;
  • identifying research or testing needs;
  • developing recommendations using the best science and data available;
  • providing education and awareness programs as to the merits and value of proper insulation systems;
  • establishing a roadmap to implement significant improvements in design and insulation system selection; and
  • establishing application best practices.

Recognizing the problems related to the lack of knowledge with mechanical insulation, the committee’s first initiative was the development of an Internet-based Mechanical Insulation Design Guide (MIDG), to be part of NIBS’ online Whole Building Design Guide (WBDG). This guide will be continually updated as deemed necessary and appropriate to reflect current and state-of-the-art information.

The committee was in agreement that the MIDG should not be another general guide specification, but instead should be a comprehensive, one-stop resource to assist the novice or the knowledgeable user in the design, selection, specification, installation, and maintenance of mechanical insulation.

Defining Mechanical Insulation

For purposes of clarity and communication, NMIC has defined the mechanical insulation market as follows: Mechanical insulation shall be defined to encompass all thermal, acoustical, and personnel safety requirements in the following categories:

  • Mechanical Piping and Equipment (Hot and Cold Applications)
  • Heating, Ventilating, and Air-Conditioning (HVAC) Applications
  • Refrigeration and Other Low-Temperature Piping and Equipment Applications

Mechanical insulation in the commercial building sector is defined to include education, health care, institutional, retail and wholesale, office, food processing, light manufacturing, and similar applications.

Mechanical insulation in the industrial sector is defined to include power, petrochemical, chemical, pulp and paper, refining, gas processing, brewery, heavy manufacturing, and similar applications.

As its name implies, the Mechanical Insulation Design Guide (MIDG) is intended to assist mechanical engineers, architects, facility owners, designers, specifiers, and users of mechanical insulation systems in commercial building and industrial applications. The concept is that with increased unbiased knowledge of mechanical insulation, indirect and direct users of mechanical insulation will be afforded the opportunity to properly specify, select, install, and maintain quality mechanical insulation systems for initiatives related to:

  • improving energy conservation;
  • reducing greenhouse gas emissions;
  • improving condensation control;
  • minimizing the opportunity for mold growth;
  • minimizing the possibility of corrosion under insulation (CUI);
  • providing a safer and better working environment;
  • increasing productivity with improved process control;
  • enhancing sustainable design initiatives;
  • improving life-cycle costs;
  • providing an exceptional return on investment (ROI); and
  • being better prepared to use other resources and evaluate both mechanical insulation materials and systems.

Scope of the MIDG

The scope of this design guide includes the design, specification, installation, and maintenance of mechanical insulation systems for use within the mechanical insulation markets. Specialized insulated air-handling products (flex-duct and duct board products) are not considered a part of the mechanical insulation industry from the perspective of this guide and, accordingly, are not addressed.

The MIDG is part of NIBS’ Whole Building Design Guide (WBDG) at www.wbdg.org. The WBDG is an evolving, Web-based resource intended to provide architects, engineers, facility managers, project managers, and other end users with design guidance, criteria, and technology for “whole buildings.” For the purposes of the MIDG, whole buildings encompass industrial and commercial building applications. The WBDG and MIDG will be continually updated and are structured as vertical portals, enabling users to access increasingly specific information as they navigate deeper into the site. The MIDG has been developed within the same principles as the WBDG. The WBDG and MIDG are available on a no-cost basis to all users.

Using the MIDG

The engineering design process is generally divided into the following phases:

  • Identify the need or define the problem.
  • Gather pertinent information.
  • Identify possible solutions.
  • Analyze and select a solution.
  • Communicate the solution.

For an insulation design project, these phases could be restated as follows:

Identify the design objectives. (Why insulate?)

  • Identify what is to be insulated. (What?)
  • Identify the location and appropriate ambient design conditions. (Where?)
  • Identify the materials and systems available. (How and with what?)
  • Analyze and determine the acceptable solutions. (How much and how to?)
  • Write the specification.

Overview of the MIDG

The MIDG is organized to help develop answers to these questions. The guide is divided into the following sections:

Design Objectives. This section aims to answer the questions why, what, and where. It includes a discussion of each of the potential design objectives (why?) and considerations for mechanical insulation systems (what and where?) that should be addressed when designing or selecting an insulation system. An insulation system can be designed for specific objectives, such as energy conservation or condensation control, or for multiple objectives. To select the right insulation system, a user needs to have a clear understanding of the objectives for the finished system.

Most engineers, architects, and end users are familiar with the use of insulation to reduce heating and cooling loads, and control noise in building envelopes. Insulation for pipes, ducts, tanks, and equipment are not as familiar. The installed cost of these insulation systems is usually a small part of the total cost of the project. As a result, mechanical insulation is often overlooked, undervalued, or improperly specified and maintained.

Mechanical insulation is primarily used to limit either heat gain or heat loss from surfaces operating at temperatures above or below ambient temperatures. Mechanical insulation may be used to satisfy one or more of the following design objectives:

  • Condensation Control
  • Energy Conservation
  • Economic Considerations (Return on Investment)
  • Environmental Considerations (Sustainability)
  • Fire Safety
  • Freeze Protection
  • Personnel Protection (Safety)
  • Process Control
  • Noise Control

In addition to these design objectives, the following considerations may require attention when designing a mechanical insulation system:

  • Abuse Resistance
  • CUI
  • Indoor Air Quality
  • Maintainability
  • Regulatory Considerations
  • Service and Location
  • Service Life

Designing insulation systems can be complicated. In some projects, multiple design objectives must be satisfied simultaneously. For example, the objective may be to provide the economic thickness of insulation and to avoid surface condensation on a chilled water line. The chilled water line may pass through various spaces within the project. Since the various spaces may have differing temperature and humidity conditions, it is likely that different insulation materials, thicknesses, and coverings may be required for a single line. Since projects may involve many lines, as well as pieces of equipment and ducts operating at various service temperatures in different environmental conditions, it is obvious that a systematic approach is required for all but the simplest applications.

Materials and Systems. This section addresses the questions of how and with what. In most cases, there are multiple types of mechanical insulation materials from which to choose for any given application. This section discusses each of the respective material categories and provides links to additional resource information and to manufacturers of the various materials.

There are a wide variety of insulation materials, facings, and accessory products available for use on mechanical systems. The list changes continually as existing products are modified, some products are phased out, and new products are developed. The task for the insulation system designer is to select the products or combination of products that will satisfy the design requirements at the lowest total cost over the life of the project. This is not easy. The designer will usually find that there are a number of products or systems that will work, and the final choice will depend on design expectations, cost, availability, or other considerations.

This section reviews various commonly used materials and describes important performance or physical properties for insulation materials and weather barriers, vapor retarders, and finishes associated with the various materials.

Selecting an insulation material and finish for a particular application requires an understanding of the requirements and physical properties associated with the various materials. Figure 2 shows a few of the physical requirements and properties discussed within the MIDG.

The MIDG has categorized the various mechanical insulation materials into the following major types:

  • Cellular
  • Fibrous
  • Flake
  • Granular
  • Reflective

Applicable materials under each category are listed alphabetically in the MIDG.

Cellular insulations are composed of small, individual cells either interconnecting or sealed from each other to form a cellular structure. Glass, plastics, and rubber may comprise the base material, and a variety of foaming agents are used.

Cellular insulations are often further classified as either open cell (cells are interconnecting) or closed cell (cells are sealed from each other). Generally, materials that have greater than 90 percent closed-cell content are considered to be closed-cell materials.

Fibrous insulations are composed of small-diameter fibers that finely divide the air space. The fibers may be organic or inorganic, and they are normally (but not always) held together by a binder. Typical inorganic fibers include glass, rock wool, slag wool, and alumina silica.

Fibrous insulations are further classified as either wool or textile-based insulations. Textile-based insulations are composed of woven and non-woven fibers and yarns. The fibers and yarns may be organic or inorganic. These materials are sometimes supplied with coatings or as composites for specific properties, such as weather and chemical resistance, reflectivity, etc.

Flake insulations are composed of small particles or flakes that finely divide the air space. These flakes may or may not be bonded together. Vermiculite, or expanded mica, is flake insulation.

Granular insulations are composed of small nodules that contain voids or hollow spaces. These materials are sometimes considered open-cell materials since gases can be transferred between the individual spaces. Calcium silicate and molded perlite insulations are considered granular insulations.

Reflective insulations and treatments are added to surfaces to lower the long-wave emittance, reducing the radiant heat transfer to or from the surface. Some reflective insulation systems consist of multiple parallel, thin sheets or foil spaced to minimize convective heat transfer. Low-emittance jackets and facings are often used in combination with other insulation materials.

Another category of material sometimes referred to as thermal insulating coatings or paints is available for use on pipes, ducts, and tanks. These paints have not been extensively tested, and additional research is needed to verify their performance from an insulation value perspective in comparison with other categories of mechanical insulation.

Most mechanical insulation systems require a covering or finish material to protect the insulation from damage. Weather, mechanical abuse, water-vapor condensation, chemical attack, and fire are all potential sources of damage. Appearance coverings are also used to provide the desired aesthetics. Depending on the location and application, the functions performed by coverings or finish materials can include the following:

  • Weather barriers. When installed on the outer surface of thermal insulation, these materials protect the insulation from weather, such as rain, snow, sleet, dew, wind, solar radiation, atmospheric contamination, and mechanical damage.
  • Vapor retarders. These materials retard the passage of water vapor into the insulation.
  • Mechanical abuse coverings. These materials protect the insulation from damage by personnel, machinery, etc.
  • Condensate barriers. Sometimes called moisture retarders, these are normally used as an inner lining for metal weather barriers, which bar the condensate that tends to form on the inner surface of the metal jacket.
  • Appearance coverings. These materials are used over insulation systems to provide the desired color or appearance.
  • Hygienic coverings. These materials are used to provide a smooth, cleanable surface for use in food processing, beverage, or pharmaceutical facilities.

These functions are performed by a number of different materials or material systems. In many cases, a single material can provide multiple functions. (For example, a metallic jacketing often serves as protection from both the weather and mechanical abuse.) There is some inconsistency and confusion in the nomenclature used for these materials. The MIDG discusses these topics and provides the user with some clarity on the various topics.

The MIDG has categorized the various weather barriers, vapor retarders, and finishes into six major types or categories (see Figure 6).

The Materials and Systems section of the MIDG also includes a discussion of insulation fabrication standards, and removable and reusable insulation covers. In addition, it includes information on an array of accessory materials that are part of the total insulation system.

MIDG Linkage to NIA’s Online MTL Product Catalog

The MIDG provides immediate linkage to specific material data, including submittal sheets, and further linkage to insulation manufacturers. This is a one-stop, online shop for manufacturers’ technical literature about specific product offerings. This direct linkage saves time in obtaining manufacturer information for specific insulation materials versus having to individually search a host of websites.

The MTL Product Catalog is the only online library of technical information for the insulation industry. It is a searchable database that allows users to find products from participating manufacturers easily and quickly on a 24-7 basis. It is the most convenient, flexible, efficient, and cost-effective way to find the most current information.

This service is provided to NIBS and the MIDG by the NIA through direct access to the association’s MTL Product Catalog. The MTL Product Catalog is continually up-dated by participating manufacturers and fabricators, providing MIDG users with current and timely information.

Installation of Mechanical Insulation

Installation of mechanical insulation is typically managed by experienced contractors who specialize in the mechanical insulation sector of the commercial, industrial, and HVAC sectors of the construction industry. As with similar construction-related activities, the project can be successful or not, depending on the design, materials selected, and—most importantly—the quality of the installation. Using an experienced and proven contractor is vital to the success of any mechanical insulation project. The lowest installation proposal may not be the best.

The insulation contractor should be familiar with the objectives of the project and be prepared to highlight and resolve any inconsistencies or errors in the specification. Often, specific insulation or accessory products are specified, and the insulation contractor must thoroughly understand the requirements for installing these products. Code compliance is generally the responsibility of the design professional, but a knowledgeable insulation contractor should understand the code requirements in his or her location and be able to help expedite resolution of compliance issues. Sometimes there are conflicts between the specifications, the manufacturers’ recommendations, and the code. Early identification and resolution of these conflicts is desirable.

The MIDG provides installation information related to the following:

  • Pre-Work Considerations
  • Finishes
  • Securing Methods
  • Pipe and Tubing
  • Insulation Pipe Hangers
  • Tanks, Vessels, and Equipment
  • Ducts
  • Special Considerations
  • Inspection and Maintenance

Within the Installation section of the MIDG, there are direct links to both Midwest Insulation Contractors Association (MICA) and Process Industry Practices (PIP) resources that provide valuable installation details and schematics.

Design Data

This section of the MIDG is a collection of information that is useful to designers and end users of mechanical insulation systems. The section contains some simple calculators that allow the calculation of heat flow and surface temperatures. Discussion of and links to more sophisticated computer programs for performing these calculations are also included. This section contains information on:

  • estimating heat loss and heat gain;
  • controlling surface temperature;
  • determining dimensions of standard pipe and tubing insulation; and
  • estimating heat loss from bare pipe and tubing.

Online MIDG calculators include the following:

  • Calculator that estimates time to freezing fluid in an insulated pipe. This calculation estimates the time for a fluid-filled pipe (no flow) to reach a freezing temperature.
  • Temperature drop calculator. This tool calculates temperature drop of a fluid flowing in a duct or pipe.
  • Simple thickness calculator. This calculator estimates the thickness of insulation required to obtain a specified surface temperature given the boundary temperatures, the conductivity of the insulation material, and the surface coefficient.
  • Simple heat-flow calculator. This calculator estimates heat flow through an insulation for flat and cylindrical systems given the temperature on each side and the effective conductivity of the insulation material.

Resources

This section of the MIDG contains an extensive list and linkage to the following resources:

  • Relevant Mechanical Insulation Standards and Guide Specifications
    • American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE)
    • Architectural Computer Services, Inc. (ARCOM-Masterspec)
    • American Society for Testing and Materials (ASTM) International
    • Midwest Insulation Contractors Association (MICA)
    • National Association of Corrosion Engineers (NACE)
    • National Fire Protection Association (NFPA)
    • Process Industry Practices (PIP)
    • Underwriters Laboratories (UL)
  • U.S. Government Agency Guide Specifications
  • Numerous References and Other Resources
  • Case Studies
  • Educational Resources
  • National Insulation Association
    • National Insulation Training Program (NITP)
    • Insulation Energy Appraisal Program (IEAP)
    • 3E Plus® Insulation Software Training
    • Awareness Presentations (Audience Tailored)
    • Insulation Science Glossary
  • American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Learning Institute
    • Professional Development Course: Mechanical Insulation Training

    • MIDG Is Making It Happen

    The Mechanical Insulation Design Guide (MIDG) is the most extensive single online resource for mechanical insulation systems developed to date. It will be continually updated and, as such, will be a “living” document. It is intended to be a comprehensive, unbiased educational database and vertical portal resource to assist all specifiers and users of mechanical insulation systems in the design, specification development, system selection, installation, and maintenance of mechanical insulation systems.

    Insulation gets very little respect and is often taken for granted. When designed, applied, and maintained properly, insulation is a powerful technology—one that provides long-lasting benefits. However, insulation is often overlooked or relegated to the bottom of the list and ignored. One reason may be that insulation systems have no moving parts, no bells and whistles, no computer chips, and no fancy gauges. This technology is not some mysterious myth. The principles of insulation are simple and not necessarily revolutionary—possibly another reason why it is often overlooked.

    However, the bottom line is that insulation can often provide an annual return on investment (ROI) of greater than 100 percent. With energy efficiency and conservation, reduction of greenhouse gas emissions, sustainable design, safety, condensation control, mold prevention, the indoor working environment, and a host of other initiatives being priorities in today’s world, maybe it is time to begin thinking about this underutilized, undervalued, and underappreciated technology differently.

    To take full advantage of this forgotten and powerful technology, it is essential to begin thinking about the value insulation can provide. Mechanical insulation is a resource that, when all of the benefits are considered, should prompt the question, “Why hasn’t this been thought of before?”

    The MIDG provides users with a single platform for increasing their knowledge of mechanical insulation in an efficient, easy-to-understand, cost-effective manner. That’s not a bad formula for a technology that can provide an unrivaled ROI opportunity in the new construction and maintenance arenas. Insulation accomplishes all of this while helping reduce U.S. dependency on foreign energy sources, improving the environment, and improving the economy.

    The official URL for the MIDG is www.wbdg.org/midg. To learn more about NIA’s MTL Product Catalog, please visit www.insulation.org/mtl. For more information on the Whole Building Design Guide, please visit www.wbdg.org.

    Acknowledgements

    Without the commitment of the National Institute of Building Sciences (NIBS) and the National Insulation Association (NIA), the MIDG would not have been possible. The support and active participation of the National Mechanical Insulation Committee (NMIC) members, made up of a long list of contributing organizations, manufacturers, fabricators, and contractors, has made the MIDG a quality educational resource. Special appreciation is extended to Christopher P. Crall, whose knowledge of mechanical engineering and thermal insulation has been invaluable in the development of the MIDG.

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NIA Sites > Insulation Outlook Magazine > Global

Insulation Materials: Polyisocyanurates

History

Polyurethanes (PU) were invented in 1937 by the German scientist Otto Bayer and his coworkers. They recognized that the polyaddition of liquid polyester or polyether diols with liquid diisocyanates yielded products that were superior to existing polyolefin plastics. In 1954, the accidental introduction of water to the reaction mixture was shown to produce flexible foams. Later, this chemistry was modified to produce rigid foams and elastomers. Today, several types of “polyols” and “polyisocyanates” are used to produce polyurethane materials that yield varying properties.

In 1967, the class of materials known as urethane modified polyisocyanurate (PIR) foams was introduced. These compounds are essentially an improvement on PU insulations, offering improved thermal stability, flame resistance, chemical resistance, and dimensional stability. During PIR production, the polyol and polyisocyanate reaction takes place at higher temperatures when compared to PU production. This allows excess isocyanate to react with itself in what is called trimerization, producing strong chains of isocyanurate crosslinks. These crosslinks are stronger than normal PU bonds. Therefore, they are more difficult to break, resulting in the improved properties.

The Manufacturing Process

During the manufacture of PIR insulation, the ratio of polyisocyanate to polyol (index) helps to determine the final properties of the foam, and therefore plays a key role in determining the foam’s application. The low-index foam insulations exhibit behavior closely resembling urethanes, since urethanes are produced at close to a 1/1 polyisocyanate/polyol ratio. As this ratio is increased, the trimerization reaction occurs, and the improved properties associated with PIR insulations become evident. Although all of these properties are important for certain applications, the improvements in dimensional stability, flame resistance, and thermal stability provide the biggest fundamental differences between PU and PIR foams.

Polyisocyanurate insulations are produced in bunstock form, either continuously or individually box poured. Because of better consistency, performance, and quality, PIR insulation produced via the continuous process is usually preferred. These large, rectangular buns are then fabricated into various shapes, including flat boards and pipe shells, which are typically 3 to 4 feet in length. These pipe shells are designed to fit directly over nominal pipe size (NPS) pipe and tubing. Complex shapes can be fabricated to fit tightly around valves, fittings, and other equipment.

Common Applications

Today, PIR foams are an important class of mechanical insulation used in a wide variety of industrial and commercial applications, including air conditioning, refrigeration, food and beverage, pharmaceutical, petrochemical, and liquefied natural gas (LNG). Polyisocyanurate insulation is also used as a core material for composite panels in applications like transportation, building construction, and temporary mobile shelters. These panel core foams are still PIR, but most are made at the lower index range. These low-index foams are better suited for panel core because of better impact resistance, adhesion, and strength properties.

Properties

What makes PIR an attractive insulation are its low density, good compressive resistance, excellent thermal conductivity, high closed-cell content, low water absorbance, low water vapor permeability, and excellent flame and smoke performance per American Society for Testing and Materials (ASTM) E84. Values for these properties can be obtained from NIA’s National Insulation Training Program (NITP) chart (see www.insulation.org/techs/insulation-materials-specification-guide.cfm), or by contacting the appropriate manufacturer of PIR insulation. Ease of fabrication and installation are also key characteristics associated with PIR insulation.

For the mechanical insulation market, PIR bunstock is widely used as pipe and vessel insulation. The applicable ASTM material standard for unfaced bunstock PIR is C591. While various grades and densities are produced, the most commonly used are Grade 2, which has an operating temperature range of -297°F to 300°F, and types IV, II, and III, with densities of 2, 2.5, and 3 pounds per cubic foot (lbs/ft3), respectively. For commercial building chilled water pipe and equipment applications, PIR insulation is included in many specifications, such as the Army Corps of Engineers, the Veterans Administration, the General Services Administration, and the private specifications of many mechanical engineering and architectural firms. For industrial applications, PIR insulation is one of the types included in the specs written by or for engineering firms, petrochemical companies, food and beverage manufacturers, and oil and gas producers.

Summary

Polyisocyanurate insulation is widely used in the mechanical and industrial insulation industry. Because of some fundamental chemistry changes, it is now filling the needs as a core material in composite panels. Ease of use, combined with excellent physical properties, means that polyisocyanurate insulation will continue to be an important part of insulation systems.

Readers who are interested in learning more about the insulation material featured here should visit the MTL Product Catalog at www.insulation.org/MTL or visit the NIA Membership Directory at www.insulation.org/membership to find a manufacturer.

NIA Members who would like to author a future column should contact publications@insulation.org

Figure 1

  1. All properties are for the generic material type and will vary by grade and by manufacturer. All properties should be verified with individual manufacturers. Properties that are not stated may or may not be an indication that a material is not appropriate for applications depending on that property. This should be verified with the specific manufacturer.
  2. Surface burning characteristics are valid for 1-inch thickness; verify results for type and any other thickness with the manufacturer.
  3. When a property is out of the specified usage range, it is shown by N/A3. Properties that are not listed or stated are so shown.
  4. All properties listed are for the core insulation material only and may not be indicative of the performance of an insulation system, including vapor retarders, adhesives, and sealants.
  5. Many materials can be used for applications outside of the ranges listed, but additional precautions must be followed. The specific manufacturer should be consulted for detailed recommendations.
  6. Some values, such as specific thermal conductivities at various mean temperatures, may be interpolated value.
  7. This chart has been established for products with current ASTM standards.
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A Monumental Undertaking

When it comes to bidding insulation projects, why not think big? That’s what TRA Thermatech did when it took on the challenge of providing the mechanical insulation for one of the largest commercial construction projects on the East Coast. The Gaylord National Resort & Convention Center, which will open its doors to guests in April 2008, has definitely been a job worth taking on, with 500,000 linear feet (97 miles) of insulated pipe and just short of 1 million square feet of duct work—enough to cover more than 20 football fields. The project is not without its challenges, though.

The National Harbor Project

The resort is part of the new National Harbor project, a $2-billion, 300-acre waterfront destination set along 1 ¼ miles of the Potomac River in Prince George’s County, Maryland. The total project will include a vast collection of retail, dining, hotel, and entertainment venues, with panoramic views of the nation’s capital and historic Old Town Alexandria, Virginia. With a prime location at the foot of the Woodrow Wilson Bridge—just off I-95 on the Washington, D.C., Capital Beltway and within an hour’s drive of three major airports (Reagan National, Dulles International, and Baltimore Washington International)—the National Harbor has been hailed as the “Gateway to the National Capital Region” and will likely become a premier destination for tourists, business travelers, and conference attendees from around the world.

According to www.nationalharbor.com, plans for the National Harbor project currently include 7.3 million square feet of mixed-use community space, with 1 million square feet of retail, dining, and entertainment space; 500,000 square feet of class “A” office space; 4,000 hotel rooms; a 470,000-square-foot convention center; 2,500 residential spaces (townhouses, luxury condominiums, and apartments); four piers, including two marinas; exclusive shopping along a mile of waterfront boardwalk; a movie theater; a children’s museum; performance venues; walking, jogging, and biking paths around the entire campus; and 10,000 on-site parking spaces. Water taxis will run to and from Alexandria, Georgetown, and historic Mount Vernon, and sightseeing tours will leave from the marinas.

A High-Visibility Project

The cornerstone of the National Harbor is the new $565-million Gaylord National Resort & Convention Center, set to become “the largest non-gaming hotel and convention center on the Eastern Seaboard.” The resort originally was to include 1,500 rooms. High demand dictated that more rooms be added, bringing the total to 2,000 amenity-laden guestrooms that include 108 lavish suites and 300 VIP Tower rooms. The Gaylord National also will feature a stunning, 18-story, 1.65-acre, multilevel atrium with views of the Potomac River and Old Town Alexandria. The atrium will be climate-controlled and constructed of glass and steel. With a dramatic gazebo, it truly will bring the outside in with sunlight and breathtaking landscaping. It is meant to reflect the power, glory, and legacy of the Capital of the United States of America.

Like the many monuments scattered throughout the area, the Gaylord National will be an awe-inspiring site. Its 470,000 square feet of convention, meeting, exhibition, and pre-function space will include the following features:

  • A 180,000-square-foot exhibition hall with 17 dedicated loading docks
  • A 50,000-square-foot ballroom, featuring a theatrical stage and an outdoor balcony that offers views of the Potomac River
  • Three additional ballrooms (30,000 square feet, 14,000 square feet, and 8,100 square feet)
  • 74 breakout rooms with maximum flexibility
  • A “Hotel Within a Hotel” area where groups can enjoy a more intimate meeting environment apart from the Convention Center’s daily activities

The convention space is only the beginning. The massive resort also will feature a nationally branded business center; 8,000 square feet of retail shopping space; six restaurants; an exclusive nightclub; a spa, salon, and fitness center; a family entertainment arcade; an indoor/outdoor swimming pool; and 80,000 square feet of terraced, outdoor “special events” lawns.

According to the online National Harbor Newsletter, the Gaylord National already has booked more than 1 million room nights—an industry record. In addition, the National Children’s Museum—a 140,000-square-foot, state-of-the-art, interactive attraction—has announced plans to open at National Harbor, promising to draw even more guests to the area. The National Harbor also announced two signature spring events: a Yacht Show that will take place May 1–4, 2008, and the International Food and Wine Festival, set for May 16–18, 2008.

TRA Thermatech Thinks Big

The entire project is being developed by The Peterson Companies, with construction managed by Perini Thompkins Joint Venture and Pierce Associates as the mechanical contractor. TRA Thermatech won the bid with Pierce Associates to install the mechanical insulation for the Gaylord National Resort & Convention Center. From the beginning, it was clear that the project would have unique insulation needs and challenges. With significant experience in commercial insulation projects, TRA Thermatech and its manpower resources were well prepared for the job.

“After being in the industry for more than 40 years, there are not many projects that come along that we get extremely excited about, but there was something special about the Gaylord project from the very beginning,” says Steve Shegogue, vice president of field operations for TRA Thermatech. “The news of this project becoming a reality was very gratifying after hearing about it in some form or another for nearly 20 years. Once we learned that we were the successful bidder on the project, I knew we had quite a challenge ahead of us.”

“The nature of preconstruction has been moving toward Design Build/Guaranteed Maximum Price (GMP) contracts with incomplete construction
documents, and that was the case with Gaylord, too,” adds Rick Pumphrey, vice president and chief estimator at TRA Thermatech. “The magnitude of this project and its compressed schedule, coupled with our strong performance history with this type of construction, placed our company on a short list of viable insulators. Gaylord has become one of the largest projects in our company’s history.”

Insulation Matters

For the Gaylord National Resort & Convention Center project, insulation was required for pipes, chillers, generator sets, and pumps. The project called for 500,000 linear feet (97 miles) of insulated pipe. It also contains just short of 1 million square feet of duct work.

The primary pipe insulation for the project is standard fiberglass insulation with white all-service jacketing. Some flexible unicellular insulation, as well as buried polyisocyanurate pipe insulation, weatherproofed cellular glass, and fire wrap, also will be used for the Gaylord project.

“One of the challenges was getting material on site and distributed throughout the project. At times, this was as much as a trailer per day with all sorts of materials, from pipe and duct insulation to fire wrap,” explains Shegogue. “That did not account for the miscellaneous sundries being delivered from our warehouse on a weekly basis.

“The biggest challenge was putting together a work force to meet the fast-track schedule,” Shegogue adds. “Assembling the team started with a support group from our office staff and included finding the right field personnel to meet the everyday challenges on a project of this size. Fortunately, we can draw from the large in-house work force that we maintain. The project started with bringing in the project field supervisor to work with the head estimator to review the drawings and go over the plan to proceed. We feel this is the best way to get our key people involved, as well as make them feel they are a part of the project team. From the very beginning, I knew that we had put together a winning team.”

On any given day, 25 to 30 skilled employees are working on the insulation portion of the project. TRA Thermatech’s first activity occurred in mid-spring 2006, and final completion of the project is estimated to occur in fall 2008. However, the first wave of rooms (making up one tower) should be completed and ready for occupancy ahead of schedule in April 2008.

Time: The Ultimate Challenge

The main factor that separated this job from others was the quick schedule for the entire project. Normally, a project of this magnitude would have taken 3 to 4 years to complete, but the resort will be turned around in just 2 years. The accelerated deadline made proper planning and organization even more critical to the success of the insulation work. TRA Thermatech’s estimating staff and general foreman initially invested nearly 400 man-hours of document review before the first piece of insulation was installed.

The tight turnaround also complicated coordination between the trades. To complete the project on schedule, some trades have to do out-of-sequence operations. This inhibits access to pipes and affects productivity.

Making History

The Gaylord National Resort & Convention Center, as well as the National Harbor project at large, will go down in history as one of the Washington, D.C., metropolitan area’s premier attractions. The sprawling waterfront boardwalk—with its restaurants, shops, and hotels—certainly will draw visitors from around the world. For those in the insulation industry, however, it is the behind-the-scenes work that goes into creating such a destination that is most fascinating.

Installing the mechanical insulation for the Gaylord National has presented challenges and called for an emphasis on quick turnaround and quality work. With all that this impressive project will offer future residents and visitors, however, all of that hard work is sure to pay off for years to come—giving TRA Thermatech a place in insulation history.

NIA Sites > Insulation Outlook Magazine > Global

Multiple Choice, Part Two: How to Choose Economic Thickness of Insulation

The November 2007 Insulation Outlook article “Multiple Choice, Part One” discussed the paradox of the past several years of energy prices more than doubling while thermal insulation thicknesses for hot piping and equipment have not increased. Most insulation thickness tables for hot service industrial piping and equipment were written before 2000, and most of these tables have not been upgraded to reflect the higher energy prices.

In the November article, the question of how insulation thicknesses should be selected was addressed. This follow-up article will look at the related question, “How should economic thicknesses (the thicknesses that balance energy savings with first cost plus maintenance cost of the installed insulation system) of insulation be selected?”

A government paper titled “Economic Thickness of Industrial Insulation”1 explains the concepts of economic thickness quite well with the qualitative graph shown in Figure 1.

The generic graph in Figure 1 shows lost energy cost, insulation cost, and total cost used to determine economic thickness for an insulated pipe.

The following three sets of curves are represented in Figure 1:

  • A curve that shows the decreasing lost energy cost for increasing insulation thicknesses
  • A curve showing the increasing installed cost for increasing insulation thicknesses (with jumps where the number of layers is increased from one to two, then from two to three layers)
  • A Total Cost curve that shows the sum of the previous two curves (the lowest point of this curve corresponds to the economic thickness)

There are many economic considerations for determining economic thickness. Rather than exploring all of them, for the purposes of this article, all variables will be held constant and only the cost of energy will vary. To determine a price for the delivered energy, as well as average ambient conditions, an 8-inch iron pipe size (IPS) insulated pipe operating at 600°F with an average annual ambient temperature of 60°F, average wind speed of 5 miles per hour (mph), and oxidized aluminum jacketing with an emissivity of 0.1 will be used. The heat source considered will be natural gas selling over a wide range of different delivered prices from $2.50 per mcf to $20 per mcf. (At press time, the delivered price to an industrial user was in the $9- to $10-per-mcf range).

To determine an economic thickness using 3E Plus®, users should select the Economics tab, give the problem an identification, and proceed. Many default conditions—such as a natural gas heating value of 1,026 British thermal units (Btus) per cubic foot, a combustion efficiency of 75 percent, and an annual fuel inflation rate of 3 percent—can be applied. A 60°F Average Annual Ambient Temperature and a 5-mph Average Annual Wind Speed should be entered. A Reference Thickness for Payback Calculations of 0 inches also should be entered for this problem. Users should select the same mineral wool pipe insulation that was used in the previous problems, and select External Jacketing Material of Aluminum, Oxidized in Service. The Installation Complexity entered should be Average, which is the default value.

The Material Price should be entered in dollars per lineal foot (LF) for 2- x 2-inch pipe insulation. 3E Plus has a default value of $4.97 per LF, including jacketing. As for the (fully burdened) Labor Rate, one can assume the default value of $38.25 per hour and place the job in Texas, where so much industrial insulation work in the United States is done. Selecting the detailed engineering report provides valuable information.

Figure 2 gives the computed installed cost of this pipe insulation at different thicknesses. Figure 2 shows that the 2-inch-thick insulation has an installed cost of $16.34 per LF and the 21/2-inch-thick insulation has an installed cost of $19.47 per LF. For thicknesses greater than 4 inches, the generated table jumps to a double-layer system. Therefore, the installed costs also jump to $40.87 per LF and $47.05 per LF to get a 5- or 6-inch thickness, respectively. Users can select 3- and 4-inch thicknesses in double layer as well, but these are somewhat more expensive than the same thicknesses in single layer. This is due to the greater number of labor hours required to install double-layer insulation.

By clicking Calculate, a detailed engineering report (see Figure 3) is produced. The table shown is for midrange, $10-per-mcf natural gas.

The result of this problem for economic thickness, using $10-per-mcf natural gas, is 4 inches. This is the insulation thickness with the lowest annualized cost (shown in the third column of numbers).

The PIP Economic Thickness chart for mineral wool insulation on a 600°F, 8-inch IPS pipe gives an economic thickness of 2.5 inches, significantly less than the 4 inches found using natural gas priced at $10 per mcf. While this 2.5 inches is only one point on one insulation economic thickness table, the comparison is representative of the existing insulation thickness tables and those economic thicknesses generated using current natural gas prices.

The jump in first cost from 4 inches ($28.24 per LF) to 5 inches ($40.87 per LF) is due to the need to go from single layer to double layer. This factor has a significant impact on limiting the economic thickness to 4 inches (as opposed to 5 inches). Also, the savings for economic thickness is $474.27 per LF per year—impressive for an insulation system that originally cost $32.06 per LF installed with metal jacketing. The payback given is 0.1 year, the minimum value given by 3E Plus. By dividing $32.06 per LF by $474.27 per LF per year, one gets an amazingly short payback of 0.068 years, which is well under 0.1 year and the equivalent of only 25 days. These numbers demonstrate convincingly that thermal insulation is extremely cost-effective in saving energy.

If this pipe were insulated with 6 inches of mineral wool instead of 4 inches, the payback would still be less than 0.1 year, but the annualized cost would be higher.

It is also interesting to run the same problem using natural gas prices at different points between $2.50 per mcf and $20 per mcf. Figure 4 shows the results of those 3E Plus calculations for economic thickness.

The chart shows that 2.5 inches is the economic thickness with natural gas priced at $2.50 per mcf, which corresponds to the PIP Economic Thickness for the same conditions. The April 1999 revision to the PIP Economic Thickness reflects a natural gas price of about $2.50 at that time. However, with the delivered price of natural gas currently in the $9- to $10-per-mcf range, the economic thickness tables need to be updated.

If the delivered price of natural gas were to double from $10 to $20 per mcf, the economic thickness would increase from 4 to 6 inches. Any newly generated insulation thickness tables would need to account for some expected natural gas price inflation.

Industrial facility owners should regenerate their insulation thickness tables for projects where energy savings is important. If the cost of energy—particularly today’s much higher natural gas and heating oil prices—has an impact on facility operating costs, then insulation thicknesses should be determined economically. The resulting thicknesses likely will be greater than those determined when energy was much cheaper.

The Bottom Line on Determining Economic Insulation Thicknesses

For new construction, or for a total insulation retrofit of existing piping and equipment, specifiers and facility owners should discard old insulation thickness tables and generate new ones using current energy costs. Use of the old insulation thickness tables results in unnecessary waste of money for heating energy. The use of new insulation thickness tables, generated using economic thicknesses and resulting in greater insulation thicknesses, will result in greater energy efficiency and can be extremely cost-effective.

1 Conservation Paper Number 46, Office of Industrial Programs, Federal Energy Administration, August 1976

Figure 1

Economic Insulation Thickness

Figure 2

3E Plus® Output—Installed Insulation Costs 3E Plus output of installed insulation costs on an 8-inch iron pipe size (IPS) pipe using $4.97 per lineal foot (LF) for 2- x 2-inch mineral wool pipe insulation and installation labor at $38.50 per hour.

Figure 3

Economic Thickness Problem 1

Figure 4

3E Plus economic thickness calculations for a 600°F, 8-inch IPS pipe with metal-jacketed, preformed mineral wool pipe insulation.

NIA Sites > Insulation Outlook Magazine > Global

Mechanical Insulation Basics Part Two: Time for a Review

This article is the second in a two-part series covering mechanical insulation basics. Part 1 of this series in the November issue discussed basic insulation science, system design and materials, and insulation thickness determination. This article will take a more detailed look at installation considerations, the specification process, and insulation system maintenance.

Installation Considerations

Not everyone can become a trained and experienced insulation estimator, but everyone who deals with mechanical insulation can at least understand the correct installation of different types of insulation systems. The NITP introduces students to the Midwest Insulation Contractors Association’s (MICA’s) manual, National Commercial and Industrial Insulation Standards, and the Process Industry Practices (PIP).

Laymen looking at an insulated industrial pipe really just see the jacketing—probably oxidized aluminum sheet. They have no concept of what may lie beneath. Figure 1, from the MICA manual, gives the details.

The system in Figure 1 consists of a double layer of high-temperature insulation material (see number 1). The insulation material is probably preformed calcium silicate, perlite, mineral wool, or fiberglass. It also has wire, banding, or tape holding the insulation sections in place (see number 3), as well as staggered and sealed lap and butt joints (see number 2). It has metal jacketing, overlapped several inches on both the lap and butt joints, and mechanically held in place with rivets (see number 4).

Every detail is there for a reason. The following are good examples of this:

  • The overall thickness provides the engineered heat loss or surface temperature limitation (also a function of the metal jacketing’s emittance).
  • The staggered joints prevent straight-through radiation and convection paths for additional heat loss.
  • The metal jacketing, with the overlaps and caulking, provides both mechanical protection and protection from rain, wind, and sunshine.

Although these details are not immediately visible, they are critical to the successful performance of the insulation system.

The average layman is even less knowledgeable about how elbows might be insulated on a large pipe operating at a high temperature. The MICA manual’s Plate 11 shows this detail (see Figure 2).

In Figure 2, number 1 refers to the pipe; number 2 to the pipe insulation; number 3 to the mitered insulation segments, cut to form a tight fit; number 4 is the metal jacketing; number 5 is the wire, banding, or tape; number 6 refers to the fitting metal jacketing gore; and number 7 refers to the mechanical fasteners. Every detail serves a function.

It takes a lot of work for a fabricator to make the insulation and metal jacketing gores, and for a skilled insulator to install these elbow materials. If the fabricator does not do the job well, the parts will not fit correctly and will either leave gaps between the insulation gores or require cutting down of the insulation gore sections to get them to fit. In cases with undersized insulation gores, there could be excess heat loss and increased surface temperatures unless the insulator takes extra time to fill in the gaps with mastics. Sometimes insulators must spend extra time to make oversized insulation gores fit. If the metal jacketing gores are not fabricated or installed correctly, rainwater may get into the insulation, causing part of it to become wet and increasing heat loss from the insulated pipe. If it is an above-ambient, low-temperature system (operating between 75° and 250°F) with uncoated carbon steel pipes, corrosion under insulation (CUI) might occur due to poor fitting or poorly caulked metal jacketing. The details make or break the mechanical insulation system.

The MICA manual and the PIP manual are current. However, there are some new materials on the market that should be included when these documents are next revised. One would be the inclusion of aerogel blanket insulation, a very low thermal conductivity insulation that has been developed this decade. In addition to its low thermal conductivity (giving it about R-10 to the inch), it is flexible, resilient, robust, and hydrophobic—an interesting combination of properties. However, when installed as a mechanical insulation, it does not meet the standard dimensions that preformed pipe and tank insulation do—namely, those given in American Society for Testing and Materials (ASTM) C585. Hence, fabricators and insulation contractors must make adjustments to get a good fit between straight sections and fittings, especially between metal-jacketed straights and preformed metal elbows.

A second new material is the class of flexible, laminated, self-adhering jacketing materials. In some applications, these may be more suitable than conventional aluminum jacketing. In particular, some have a zero vapor permeance and seal air (and vapor) tightly. In addition, with the self-adhered joints, water intrusion should be less of a problem.

Specification Process

The mechanical insulation industry is doing better today than it was 6 years ago when the NITP began. Those in the industry are running to keep pace with new construction projects “coming out of the ground,” as well as those still “in the pipeline.” The specification process is much more important now because of the abundance of work being specified in preparation for new construction.

Some current specifications are new, and others have simply been taken off the shelf, dusted off, and included with project bid documents. In either case, the specs still accomplish the same goal: to allow the owner or operator (perhaps through an engineering firm) to communicate to the bidding contractors what is required for a project. For mechanical insulation, this includes the types of materials (including accessory materials, such as those that hold the insulation jacketing onto the insulated pipe), insulation thicknesses, installation requirements, scope, technical submittal requirements, and quality requirements. With new projects, the insulation specification is more important than ever.

The contractor is advised to read the specification thoroughly before submitting a base bid. Of course, contractors also must understand the schedule requirements to provide a good proposal. If they think they can improve system performance and/or reduce the installed cost while improving the schedule, they may be allowed or even encouraged to provide an alternate bid.

When offering a base bid, contractors are not responsible for system performance as long as they follow the specification exactly to every detail. If an alternate bid is accepted, then the contractor takes on some additional risk, even if the client’s engineering firm approved the bid.

Different materials can be used, within their temperature limitations, on any particular application. For example, to insulate 45°F chilled water lines, numerous materials can be specified, including all service jacket (ASJ) or foil-scrim-kraft (FSK) jacketed fiberglass and mineral wool pipe insulation; flexible elastomeric foam tube or sheet; or preformed pipe insulation made from polystyrene, polyisocyanurate, phenolic foam, or cellular glass.

Some materials are less expensive to purchase than others, some are less expensive to fabricate than others, and some are easier and faster to install. Owners and operators want the lowest installed cost. However, if they want the system to last, they should take durability and longevity into account when writing the specification. If getting the lowest first cost for the project is a high priority, they may get just that—a system that performs well at first, but not for more than a couple of years. If owners and operators want an insulation system that lasts, they must have an engineer write the specification with durability in mind.

A well-maintained insulation system should last 20 to 25 years. For that to happen, however, the system must be intelligently specified, and the resulting specification must be followed by the insulation contractor. To do that, the general contractor and/or the owner should know and enforce that specification. For the owner/operator, the rule that holds is “pay now or pay later.” Specifiers have a variety of sources for technical information on products that make up mechanical insulation systems. Some of these include the following:

  • The National Insulation Association’s (NIA’s) website (www.insulation.org)
  • MICA’s National Commercial & Industrial Insulation Standards Manual (6th Edition)
  • The ASTM Book of Standards, Volume 04.06 (updated every year)
  • The North American Insulation Manufacturers Association’s (NAIMA’s) 3E Plus® computer program (updated periodically)
  • Arcom MASTERSPEC
  • PIP manual on mechanical insulation (updated in 2006)
  • The American Society of Heating, Refrigerating and Air Conditioning Engineers’ (ASHRAE’s) 2005 Handbook of Fundamentals, Chapter 26 (to be updated in 2009)

At www.insulation.org, the Guide to Insulation Product Specifications, the Insulation Materials Specification Guide, and the MTL Product Catalog are good resources for specifiers. Additional references, including past articles from Insulation Outlook in the magazine’s archives, can be of value as background material.

The ASTM Book of Standards, Volume 04.06 includes specifications for most of the different insulation materials that are commercially available (two exceptions are microporous insulation and aerogel blanket insulation, both of which are currently in the process of being developed by ASTM Committee C16). ASTM also has testing standards, such as for testing thermal conductivity, compressive strength, and so forth. These are referenced in the ASTM material standards and may be referenced in a project specification. Occasionally, military specifications (MILSPECS) are referenced.

Chapter 26 of ASHRAE’s 2005 Fundamentals Handbook covers “Thermal Insulation for Mechanical Systems.” This chapter is particularly helpful for commercial building mechanical insulation system design. Also, the MASTERSPEC series for all building construction can be a great aid to specifying engineers who are starting from scratch on a new project.

Insulation System Maintenance

Facility owners and operators may have an excellent insulation specification, purchase quality materials, and have the materials installed exactly as specified, but if they do not properly maintain the system, performance will decrease over time. Nothing lasts forever. The better an insulation system is maintained, the longer it lasts and the better its performance. Maintenance is not free, but it is critical.

Mechanical insulation is used to reduce energy use, control a process, provide personnel protection, prevent condensation, provide freeze protection, and more. If the insulation becomes crushed, gets wet, or degrades from severe vibration, it will not provide the thermal performance for which the insulation system was designed.

Again, it is pay now or pay later. Usually, paying later is much more expensive than it would have been to maintain the system all along.

When owners and operators consider today’s energy costs (for example, $10 per million Btus of natural gas) and evaluate their insulation systems for missing or damaged materials, it is obvious that fixing insulation pays for itself within a few months, if not a few weeks. (See “How Many Barrels of Oil Can Mechanical Insulation Save?” at www.insulation.org/articles/article.cfm?id=IO050505.) Typical return on investment (ROI) for insulation upgrade projects occurs in less than a year.

Poorly maintained mechanical insulation can result not only in higher than design energy use, but also in other costly problems. Corrosion under insulation can occur in mild-temperature (75° to 250°F) uncoated carbon steel surfaces when the insulation gets and stays wet for an extended period of time, particularly in a rainy location close to a body of salt water. Water intrusion occurs when the metal jacketing is not well maintained—including caulking of all the joints and maintaining that caulking. Metal jacketing can leak around joints, particularly where there are penetrations for pipe hangers, supports, or fittings. Over time, if CUI develops as a result of wet insulation, remediation of the problem can be extremely costly.

If a chilled pipe’s vapor retarder or vapor barrier is not well maintained (assuming that it was well specified in the first place), moisture likely will get into the insulation and migrate to the chilled pipe. Besides the obvious energy waste, dripping water can lead to mold growth, corrosion of building structural members, destroyed ceiling panels, electrical shorts, and more.

Mechanical insulation systems must be well maintained, and they do not maintain themselves. Facility owners and operators must put sufficient money into their budgets and then make certain that the work gets done. To do otherwise is simply uneconomical and, in some cases, unsafe.

Back to Basics

Numerous resources are available to help engineers design an insulation system for a particular application and make sure it is installed correctly. Collectively, these resources provide an extensive knowledge base and can be extremely useful.

It is critical to review mechanical insulation basics with an emphasis on proper installation and maintenance every once in a while. When insulation is correctly designed and installed as part of a system, it provides a cost-effective solution to excess heat loss or heat gain.

Figure 1

MICA Manual, Plate 1

Figure 2

MICA Manual, Plate 11

Figure 3

A well-maintained insulation system performs as designed.

Figure 4

A poorly maintained insulation system has damaged and/or missing insulation that does not perform as designed.

NIA Sites > Insulation Outlook Magazine > Global

Insulation Materials Guide

Definition of Insulation

Insulation is defined as those materials or combinations of materials that retard the flow of heat energy by performing one or more of the following functions:

  1. Conserve energy by reducing heat loss or gain.
  2. Control surface temperatures for personnel protection and comfort.
  3. Facilitate temperature control of a process.
  4. Prevent vapor flow and water condensation on cold surfaces.
  5. Increase operating efficiency of heating/ventilating/cooling, plumbing, steam, process, and power systems found in commercial and industrial installations.
  6. Prevent or reduce damage to equipment from exposure to fire or corrosive atmospheres.
  7. Assist mechanical systems in meeting U.S. Department of Agriculture (USDA) Food and Drug Administration (FDA) criteria in food and cosmetic plants.

The temperature range within which the term “thermal insulation” will apply is from -73.3°C (-100°F) to 815.6°C (1,500°F). All applications below -73.3°C (-100°F) are called cryogenic, and those above 815.6°C (1,500°F) are called refractory.

Thermal insulation is further divided into the following three general application temperature ranges:

  1. Low-Temperature Thermal Insulation
    1. 15.6°C to 0°C (60°F to 32°F)—cold or chilled water
    2. -0.6°C to -39.4°C (31°F to -39°F)—refrigeration or glycol
    3. -40.0°C to -73.3°C (-40°F to -100°F)—refrigeration or brine
    4. -73.9°C to -267.8°C (-101°F to -450°F)—cryogenic
  2. Intermediate Temperature Thermal Insulation
    1. 16.1°C to 99.4°C (61°F to 211°F)—hot water and steam condensate
    2. 100°C to 315.6°C (212°F to 600°F)—steam and high-temperature hot water
  3. High-Temperature Thermal Insulation
    1. 316.1°C to 815.6°C (601°F to 1,500°F)—turbines, breechings, stacks, exhausts, incinerators, and boilers

Generic Types and Forms of Insulation

Insulation will be discussed in this article according to its generic types and forms. The type indicates composition (such as glass or plastic) and internal structure (such as cellular or fibrous). The form implies overall shape or application (such as board, blanket, or pipe insulation).

Insulation Types

Fibrous insulation. This type of insulation is composed of small-diameter fibers, which finely divide the air space. The fibers may be either perpendicular or horizontal to the surface being insulated, and they may or may not be bonded together. Silica, rock wool, slag wool, and alumina silica fibers are used. The most widely used insulations of this type are the glass fiber and mineral wool types of insulation.

Cellular insulation. This type of insulation is composed of small, individual cells separated from each other. The cellular material may be glass or foamed plastic, such as polystyrene (closed cell), polyurethane, polyisocyanurate, plyolefin, and elastomeric.

Granular insulation. This is composed of small nodules that contain voids or hollow spaces. It is not considered a true cellular material since gas can be transferred between the individual spaces. It may be produced as a loose or pourable material, or combined with a binder and fibers to make a rigid insulation. Examples are calcium silicate, expanded vermiculite, perlite, cellulose, diatomaceous earth, and expanded polystyrene.

Insulation Forms

Insulation is produced in a variety of forms suitable for specific functions and applications. The combined form and type of insulation determine its proper method of installation. The forms most widely used include the following:

  • Rigid boards, blocks, sheets, and preformed shapes, such as pipe insulation, curved segment, and lagging: Cellular, granular, and fibrous insulations are produced in these insulation forms.
  • Flexible sheets and preformed shapes: Cellular and fibrous insulations are produced in these forms.
  • Flexible blankets: Fibrous insulations are produced in flexible blankets.
  • Cements (insulating and finishing): Produced from fibrous and granular insulations and cement, they may be of the hydraulic setting or air-drying type.
  • Foam: Poured or froth foam used to fill irregular areas and voids. Spray used for flat surfaces.

Properties of Insulation

Not all properties are significant for all materials or applications. Therefore, many are not included in manufacturers’ published literature. In some applications, however, omitted properties may assume extreme importance (like when insulations must be compatible with chemically corrosive atmospheres.)

If the property is significant for an application and the measure of that property cannot be found in manufacturers’ literature, effort should be made to obtain the information directly from the manufacturer, testing laboratory, or insulation contractors association.

The following properties are referenced only according to their significance in meeting design criteria of specific applications. (More detailed definitions of the properties themselves can be found in the online glossary of insulation terms at www.insulation.org/techs/glossary.cfm.)

Thermal properties of insulation. The following insulation properties are the primary consideration when choosing the type and form of insulation for specific projects:

  • Temperature limits: Upper and lower temperatures within which the material must retain all of its properties.
  • Thermal conductance “C”: The rate of heat flow for the actual thickness of a material.
  • Thermal conductivity “K”: The rate of heat flow based on a 25-mm (1-inch) thickness.
  • Emissivity “E”: This is significant when the surface temperature of the insulation must be regulated, as with moisture condensation or personnel protection.
  • Thermal resistance “R”: The overall resistance of a “system” to the flow of heat.
  • Thermal transmittance “U”: The overall conductance of heat flow through an insulation system.

Mechanical and chemical properties of insulation. Properties other than thermal must be considered when choosing materials for specific applications. These properties include the following:

  • Alkalinity (pH or acidity): Significant when corrosive atmospheres are present. Insulation must not contribute to system corrosion.
  • Appearance: Important in exposed areas and for coding purposes.
  • Breaking load: In some installations, the insulation material must “bridge” over a discontinuity in its support.
  • Capillarity: This must be considered when a material may be in contact with liquids.
  • Chemical reaction: Potential fire hazards exist in areas where volatile chemicals are present. Corrosion resistance must also be considered.
  • Chemical resistance: This is significant when the atmosphere is salt or chemical laden.
  • Coefficient of expansion and contraction: This enters into the design and spacing of expansion and contraction joints and/or the use of multiple-layer insulation applications.
  • Combustibility: This is one of the measures of a material’s contribution to a fire hazard.
  • Compressive strength: This is important if the insulation must support a load or withstand mechanical abuse without crushing. If, however, cushioning or filling in space is needed as in expansion and contraction joints, low-compressive-strength materials are specified.
  • Density: A material’s density affects other properties of that material, especially thermal properties.
  • Dimensional stability: This is significant when the material is exposed to atmospheric and mechanical abuse, such as twisting or vibration from thermally expanding pipe.
  • Fire retardancy: Flame spread and smoke developed ratings should be considered.
  • Hygroscopicity: The tendency of a material to absorb water vapor from the air.
  • Resistance to ultraviolet light: This is significant if the application is outdoors.
  • Resistance to fungal or bacterial growth: This is necessary in food or cosmetic process areas.
  • Shrinkage: This is significant on applications involving cements and mastics.
  • Sound absorption coefficient: This must be considered when sound attenuation is required, as it is in radio stations, some hospital areas, etc.
  • Sound transmission loss value: This is significant when constructing a sound barrier.
  • Toxicity: This must be considered in food processing plants and potential fire hazard areas.

Major Insulation Materials

The following is a general inventory of the characteristics and properties of major insulation materials used in commercial and industrial installations.

Calcium Silicate

Calcium silicate is a granular insulation made of lime and silica, reinforced with organic and inorganic fibers, and molded into rigid forms. Service temperature range covered is 37.8°C to 648.9°C (100°F to 1,200°F). Flexural strength is good. Calcium silicate is water absorbent. However, it can be dried out without deterioration. The material is noncombustible and used primarily on hot piping and surfaces. Jacketing is field applied.

Glass

  • Fibrous. This type is available as flexible blanket, rigid board, pipe insulation and other premolded shapes. Service temperature range is -40°C to 37.8°C (-40°F to 100°F). Fibrous glass is neutral; however, the binder may have a pH factor. The product is noncombustible and has good sound absorption qualities.
  • Cellular. This type is available in board and block form capable of being fabricated into pipe insulation and various shapes. Service temperature range is -267.8°C to 482.2°C (-450°F to 900°F). It has good structural strength, but poor impact resistance. The material is non-combustible, non-absorptive, and resistant to many chemicals.

Mineral Fiber (Rock and Slag Wool)

Rock and/or slag fibers are bonded together with a heat-resistant binder to produce mineral fiber or wool available in loose blanket, board, pipe insulation, and molded shapes. Upper temperature limits can reach 1,037.8°C (1,900°F). The material has a practically neutral pH, is noncombustible, and has good sound-control qualities.

Expanded Silica (Perlite)

Perlite is made from an inert siliceous volcanic rock combined with water. The rock is expanded by heating, causing the water to vaporize and the rock volume to expand. This creates a cellular structure of minute air cells surrounded by vitrified product. Added binders resist moisture penetration, and inorganic fibers reinforce the structure. The material has low shrinkage and high resistance to substrate corrosion. Perlite is noncombustible and operates in the intermediate and high temperature ranges. The product is available in rigid, preformed shapes and blocks.

Elastomeric

Foamed resins combined with elastomers produce a flexible cellular material. Available in preformed shapes and sheets, elastomeric insulations possess good cutting characteristics and low water and vapor permeability. The upper temperature limit is 104.4°C (220°F). Elastomeric insulation is cost efficient for low-temperature applications with no jacketing necessary. Resiliency is high. Consideration should be made for fire retardancy.

Foamed Plastic

Insulation produced from foaming plastic resins creates predominately closed-cellular rigid materials. K-values decline after initial use as the gas trapped within the cellular structure is eventually replaced by air. Check manufacturers’ data for details. Foamed plastics are lightweight with excellent moisture resistance and cutting characteristics. The chemical content varies with each manufacturer. Available in preformed shapes and boards, foamed plastics are generally used in the low and lower intermediate service temperature range -182.8°C to 148.9°C (-297°F to 300°F). Consideration should be made for fire retardancy of the material.

Refractory Fiber

Refractory fiber insulations are mineral or ceramic fibers, including alumina and silica, bound with extremely high-temperature binders. The material is manufactured in blanket or rigid form. Thermal shock resistance is high. Temperature limits reach 1,648.9°C (3,000°F). The material is noncombustible. The use and design of refractory range materials is an engineering art in its own right and is not treated fully in this article, although some refractory products can be installed using application methods illustrated here.

Insulating Cement

Insulating and finishing cements are a mixture of various insulating fibers and binders with water and cement to form a soft, plastic mass for application on irregular surfaces. Insulation values are moderate. Cements may be applied to high-temperature surfaces. Finishing cements or one-coat cements are used in the lower intermediate range and as a finish to other insulation applications. Check each manufacturer for shrinkage and adhesion properties.

For more information, please see the online version of this article at www.insulation.org/techs/standardsmanual_materials.cfm#mat.

NIA Sites > Insulation Outlook Magazine > Global

Websites that Work

There is so much information on the Internet these days, it is sometimes hard to determine what the most useful and practical sites are for industry information. With so much to choose from, the most vital information can get lost in the search-engine shuffle.

That’s why we’ve done the research for you and determined which sites provide the most useful information on economic research, green building, legislative updates, labor issues, and new technology. Here is what we found.

First Things First

Insulation.org is a one-stop shop for mechanical and industrial insulation industry news, products, training resources, and more. This is the most comprehensive, simple-to-use website devoted to the industrial and specialty insulation industry available. No other source delivers such a broad range of resources on both the National Insulation Association (NIA) and the industry as a whole. Keep up with the latest event information for NIA’s annual convention or Committee Days meetings; search the online membership directory for an insulation professional; or browse the articles database, which is filled with valuable information from Insulation Outlook and NIA News (NIA’s official newsletter). There is also a feature that allows users to e-mail articles to colleagues.

The MTL Product Catalog at Insulation.org allows manufacturers to upload PDF files of their technical literature, and the site allows users access to NIA’s Guide to Insulation Product Specifications and Insulation Materials Specification Guide. The online Bookstore features unique products, such as the “Technical Energy Solutions: The Power of Insulation” brochure, the Insulation Estimator’s Handbook, and the Safety Handbook for Insulation and Abatement Workers. Insulation training programs offered by NIA include 3E® Plus, the National Insulation Training Program (NITP), and the Insulation Energy Appraisal Program (IEAP), and users can register online for all of these training opportunities. Insulation.org users can also sign up to receive NIA’s free E-News Bulletin, which provides up-to-the-minute industry news in an electronic format.

When searching for insulation-related information, Insulation.org is truly the first site users should visit. It is wise for users to bookmark this site on their desktops, so that they can quickly refer to it over and over again.

Economic Outlooks

There are several great sites that provide construction industry economic data. These sites are valuable for various reasons. Here is a list of our favorites:

  • The Resource Center at www.construction.com/ResourceCenter from McGraw-Hill Construction provides recently published reports, a directory of useful regional publications, an Industry Watch that details industry trends and forecasts, an industry event listing, and more.
  • ENR.com provides construction industry news, plus links to business and labor features. The Construction Economics page at http://enr.construction.com/features/conEco/default.asp provides a weekly price update for four key construction materials along with comments on recent trends.
  • Buildingteamforecast.com offers construction forecasts, construction starts, and economic indicators. Along with the latest industry news, this site also provides in-depth employment statistics. Users can click Mann at Work for a summary of construction-related economic announcements from around the Web.
  • Industrialinfo.com gives users a worldwide perspective, and it provides vital industry information and analytical tools. The North America Industrial Process & Manufacturing page (www.industrialinfo.com/marketcoverage.jsp?qiSessionId
    =D59EC7D5A05F87A68D33643E69DC32B7.mince    ) covers the Heavy Industrial Process and Manufacturing markets.

Green Guides

It is no secret that one of the hottest trends in the construction industry today is green building. But which green technologies are really practical and cost-effective to implement? Insulation is certainly one. The following websites offer users expanded knowledge about developing green facilities:

  • USGBC.org is the U.S. Green Building Council’s website. This site has information on everything from education to expos. Its Green Building 101 is a must-read, and it also offers valuable Leadership in Energy and Environmental Design (LEED) information at USGBC.org/LEED. The site offers additional green building resources, including publications, research, and online courses.
  • Environmental Design+Construction magazine’s website at EDCmag.com focuses in on successful green building projects and how they were accomplished. The GREEN Book at this site is a great resource for architects and designers to find green products and services. It provides an alphabetical listing of suppliers cross-referenced by product name and Construction Specifications Institute (CSI) code.
  • Greenbuilder.com is another resource for information on sustainability in design. It provides a Green Building Professionals Directory and links to several other valuable resources.
  • The CSI Foundation is now in the process of developing GreenFormat.com, a site that will enable manufacturers to report the sustainability-measuring properties of their products for use by designers, constructors, and building operators. This site will be launched in 2008 and will offer the building industry an easily accessible database of green building products and manufacturers.

The Latest Legislation

It pays to stay updated on legislative affairs at the local, state, and federal levels. The following websites are some of our go-to legislative resources for the latest information:

  • According to ASE.org, The Alliance to Save Energy promotes energy efficiency worldwide to achieve a healthier economy, a cleaner environment, and greater energy security. This interactive website provides information for consumers, educators, policy makers, energy professionals, and more. It is a one-stop shop for the latest news and program information, with a goal of extending the world’s energy supplies through increased energy efficiency. Users can subscribe to any of the Alliance’s free news and information services online for the latest energy-efficiency updates.
  • For the latest information on science and technology, energy resources, the environment, prices and trends, national security, and safety and health as they relate to energy, there is no better resource than DOE.gov. This site offers Quick Clicks for consumers, researchers, educators, students, and employees. It also offers energy-saving tips, the latest news, press releases from the U.S. Department of Energy (DOE), and a Quick Reference section with valuable industry links. Special features include in-depth articles on state and local news stories, plus a look at global programs and developments. Plus, see how DOE programs are performing with a special report at Expectmore.gov.
  • Need the latest information on energy efficiency tax credits? The North American Insulation Manufacturers Association’s (NAIMA’s) website at NAIMA.org offers a wealth of information, including policy updates that affect the insulation industry. Under Federal and State Affairs, users can view the latest federal, state, and international energy activities. This site is also where companies can go for an online application form for NAIMA’s Insulation Quality (IQ) Award, which honors selected metal building contractors who are committed to insulation quality as a key factor in best practices.

A Wider Recruiting Net

The impending manpower shortage in the United States is a real issue for insulation manufacturers, contractors, distributors, fabricators, specifiers, laminators, and other end users. The following websites can be used for recruitment and career development activities, including searching for jobs, advertising positions, and researching job descriptions:

  • The National Insulation Association (NIA) offers a Job Board as a free service to its members at www.insulation.org/careers/classifieds/index.cfm. Employers can submit job openings for salaried positions only, and job seekers can search by geographic region. Insulation.org/careers also provides links to an industry overview; a guide to careers in insulation contracting; an overview of distribution and fabrication that highlights various jobs in those sectors; a plethora of human resource forms and documents, such as employee applications, employee termination forms, evaluations, offer letters, and much more; and links to other construction career sites.
  • ConstructionJobs.com is a job board and resume database for the construction, design/build, and engineering industries. This site allows employers to post open positions and allows job seekers to post resumes and search for openings of interest to them. The site also provides a Career Center, which offers useful tools like resume writing tips, interviewing advice, job-hunting tips, and negotiating expertise.
  • Monster.com might be the most recognized career site available on the Web. Here users can create an account and post resumes, take advantage of the QuickApply feature when they see a job they like, and even participate in job forums and learn about career fairs and other upcoming opportunities. There is also helpful information on education, choosing a career path, and how to pay for school. Employers can take advantage of this massive site by posting jobs, searching resumes, and recommending that employees read some of the useful on-the-job articles that provide valuable tips for top-quality performance. The site also provides hiring tips and trends. According to Monster, the site delivers millions more active job seekers than any other career site. In fact, every day on Monster.com, job seekers post more than 27,000 new resumes and conduct 3.9 million job searches. Relevant job categories include Construction, Mining, and Trades; Architectural Services; Energy/Utilities; Engineering; and more.
  • Another useful site with similar job-search features and categories is Careerbuilder.com. In addition to the ability for employees to post resumes and search job openings and for employers to post openings and search resumes, this site will send users job alerts and recommendations, up-to-date e-mails that include the latest and most applicable information that is relevant to them. It also allows users to save jobs and review them again at a later date. It provides career tests and salary calculators, and it offers employers numerous interviewing strategies, hiring solutions, and advice on how to hire high-quality workers.

Looking Forward to the Future

The Internet is always changing, with new information becoming available every day. The following exciting, insulation-related developments are coming soon to a computer near you:

  • The National Insulation Association (NIA) has taken a strong leadership role in the development of a new resource called the Mechanical Insulation Design Guide (MIDG). This Internet-based guide will be part of the National Institute of Building Sciences’ (NIBS’) Whole Building Design Guide (WBDG), which is housed at WBDG.org. This site already reaches hundreds of thousands of users per month, and the design tree approach the MIDG takes to determining the proper insulation for a project will be a one-of-a-kind online offering. The MIDG will be a comprehensive resource to assist specifiers and other insulation end users in the design and specification of mechanical insulation systems for a wide range of applications. As the name implies, the MIDG is primarily intended to help designers, specifiers, facility owners, and other insulation end users determine the proper types of insulation for the specific needs of their projects. The engineering design process is generally divided into a number of phases along these lines:

    • Identify the need or define the problem.
    • Gather pertinent information.
    • Identify possible solutions.
    • Analyze and select a solution.
    • Communicate the solution.

    For an insulation design project, these phases could be expanded and restated as follows:

    • Identify the design objectives. (Why insulate?)
    • Identify what is to be insulated. (What?)
    • Identify the location and appropriate ambient design conditions. (Where?)
    • Identify the materials and systems available. (How?)
    • Analyze and determine the acceptable solutions. (How much?)
    • Write the specification. (How to?)

    So for insulation, the design process boils down to answering these basic questions:
    Why insulate? What? Where? How? How much? How to?

    The MIDG is organized to help answer these questions. It is divided into the following five sections:

    • Design Objectives (Why, What, and Where?)
    • Materials and Systems (How?)
    • Installation (How?)
    • Design Data (How much?)
    • Resources (Where?)

    Mechanical insulation is important to facility operations and manufacturing processes, and is often overlooked and undervalued. However, the development of the MIDG is a great step toward increasing knowledge and awareness, and providing education to end users who need their insulation questions answered. Look for the MIDG at WBDG.org in early 2008.

  • For the latest information from the energy industry, one needs to look no further than www.eere.energy.gov. This U.S. Department of Energy (DOE) Energy Efficiency and Renewable Energy site provides information on everything from building technologies to solar energy. It is a great site for staying up to date on energy-saving strategies. One such strategy is the DOE’s Save Energy Now (SEN) program, an initiative that helps American businesses, factories, and manufacturing facilities save energy and thrive despite variable energy costs. To learn more about SEN, visit www1.eere.energy.gov/industry/saveenergynow/index.html. Through SEN, the DOE’s Industrial Technologies Program (ITP) helps industrial plants operate more efficiently and profitably by identifying ways to reduce energy use in key industrial process systems. This innovative program’s Energy Savings Assessments have already yielded major bottom-line benefits and will continue to do so in the future. The information at this site is definitely worth a closer look.
  • The Midwest Insulation Contractors Association (MICA) is the author and publisher of the nationally recognized Commercial and Industrial Insulation Standards Manual. This 347-page document is considered the authority on standards for the industry, and now some of the most critical information from the sixth edition of this manual is at www.micainsulation.org/standards/index.php. Use this site for standards for insulation materials, insulation systems, plates, and specification writing.

    • Information at Your Fingertips

    The Internet is arguably the most valuable research resource available today. Not only can it help users see the big picture, with economic and legislative updates, as well as new technologies, but it is also extremely valuable at the individual level, as employees look for just the right workers and association members learn how to participate in their industry. These sites will help even the most hesitant users find just what they are looking for—quickly and simply.

NIA Sites > Insulation Outlook Magazine > Global

Survey Indicates Commercial and Industrial Insulation Market Revenue Exceeds $9 Billion

Since the first survey was completed in 1997, the market has grown from $6.2 billion to $9.2 billion, a 48.4% increase in 10 years for a slightly less than 4% compounded annual growth rate. The majority of that growth has occurred over the last 4 years, from January 2003 to December 2006. From 1997 to 2002 (6 years), it was basically flat, yielding only 1.6% overall market growth. The years 2003 to 2006 (4 years) have yielded 46% growth, or approximately a 10% compounded annual growth rate. It is safe to say, the “NIA World” has grown.

Based on the survey methodology, $9.2 billion is a conservative number. The survey does not include data related to metal building insulation (MBI); heating, ventilating, and air-conditioning (HVAC) duct liner; original equipment manufacturer (OEM) products; building insulation; refractory products; other specialty insulations; or insulation products or technologies not currently encompassed in the NIA World of mechanical insulation products. The value added by fabricators and laminators has not been accounted for, nor has the potential impact of imported products been included. The consistency of participation by larger manufacturers, combined with the consistency of tabulating the results, provides some comfort when examining growth rates for the mechanical insulation market segment.

As with previous surveys, an informal survey revealed some changes that influenced the overall market size calculation and yielded some interesting information.

The ratio of products flowing through the distribution channel versus being “sold direct” has remained constant or increased slightly. With continued consolidation and, in some cases, importers’ efforts to circumvent the distribution channel, the support of the distribution channel remains strong.

The ratio of labor to material has changed significantly. It has changed to 72% labor and 28% material from a comparative ratio of 75/25 in 2004. The reason for the shift has been primarily attributed to a combination of greater productivity and the sustained price increases in metallic products. The mixture of the type of work and new construction versus maintenance activities would also have affected the labor-to-material ratio.

Margins were flat to down for the distribution channel, while the contracting segment experienced a significant increase. The distribution channel had experienced some margin increase from late 2004 through mid-2006, but by the end of 2006 erosion of those achievements had started to occur. The increase in contracting margins appears to be driven by a shortage of labor, smarter work practices, and increased productivity.

The data obtained in the NIA survey process does not provide detailed information to determine what percentage of the overall market growth was in units or dollars. That question was asked in the informal survey to which there were varying results. It is generally believed that dollar growth exceeded unit growth.

Surveys can be a useful tool in all facets of the industry. The results can provide meaningful benchmarks upon which to measure performance or to establish objectives; provide meaningful and supportive information to shareholders, investors, and the financial community; provide current and potential employees with useful information; be used in developing strategic and tactical business or sales plans; and be used in reviewing historical trends, projecting future performance, and for a large array of other initiatives. This survey provides a 30,000-foot view of the mechanical insulation segment, which is a portion of the commercial and industrial insulation market.

To those NIA Associate members that participated in the 2006 survey and to all of the sponsors (contributors to the efforts of NIA’s Foundation), thank you. The Foundation’s continual outreach effort to increase awareness of the value of insulation is making a difference.

The industry is strong and has grown significantly in a short period of time. Was that growth driven by the general economy, the increase in energy cost and energy conservation initiatives, the increased focus on the environment, or the efforts of NIA’s Foundation? The answer is probably just a simple yes.

When examining that growth question, it is interesting to note that each of the historical factors can also serve as a listing of future growth opportunities. These factors include the following: 1) energy and the environment are going to remain in the forefront in both the political and financial worlds for the foreseeable future; 2) the Foundation’s efforts are continuing and gaining momentum; 3) many industry segments of the market are forecasting growth over of the next several years; 4) maintenance activities are reaching the point where they can’t be delayed much longer; and 5) sustainable design activities are increasing. According to some economists, the general economy and the continual threat of terrorism appear to be the wild cards.

The commercial and industrial insulation industry has confronted many obstacles in its history. It has always responded, rebounded, and grown over time. Our industry is strong and positioned to address the opportunities and challenges that present themselves in future years. NIA is looking down the road to your future and charting the course for success.

Figure 1
NIA Sites > Insulation Outlook Magazine > Global

Multiple Choice, Part 1
Selecting Proper Insulation Thickness Helps Increase Energy Efficiency

An interesting paradox of the past several years is that energy prices have more than doubled while thermal insulation thicknesses for hot piping and equipment have not increased. In fact, most insulation thickness tables for hot service industrial piping and equipment were written before 2000—well before the recent energy price bonanza—and most of these tables have not been upgraded to reflect the higher energy prices.

This has caused facility owners to spend more money for energy than is necessary, when energy use could be cost-effectively reduced with appropriate insulation thicknesses. It also raises the following questions: How should insulation thicknesses be selected, and how should economic thicknesses of insulation be selected (economic thicknesses being that balance of energy savings with first cost plus maintenance cost of the installed insulation system)? This article will answer the first of these questions, and the second question will be addressed in more detail in a follow-up article in the December issue.

According to the National Insulation Association’s (NIA’s) National Insulation Training Program (NITP), the four primary reasons for insulating (excluding specialty cases of noise reduction and fire protection) include the following:

  • Process Control
  • Personnel Protection
  • Condensation Control
  • Energy Savings

In the NITP, students are introduced to the computer program 3E Plus®, available now in Version 4.0, Build 33, for free download from the North American Insulation Manufacturers Association (NAIMA) at www.pipeinsulation.org. With this computerized heat-transfer tool, plus appropriate design conditions and thermal conductivity information on a particular type of insulation, users can determine appropriate thicknesses using criteria for one of the above four reasons for insulating. NIA offers a comprehensive, 3.5-hour training program for 3E Plus users. To learn more, please visit www.insulation.org/training/seminar.

Thermal insulation markets—and, therefore, specified insulation thicknesses—are directly affected by trends in energy prices. Before one can determine insulation thicknesses, it is important to understand the latest trends.

Thermal Insulation Thicknesses and Energy Prices

The world watched in amazement as spot market crude oil prices rose from about $10 per barrel in 1998 to more than $77 per barrel in midsummer 2006, dropped back to below $60 per barrel, and then rose again to the $79- to $83-per-barrel range in early fall 2007. Natural gas rose from a wholesale price of around $3 per thousand cubic feet (mcf) 5 years ago to about $6 per mcf. The price of natural gas has been even more volatile than that for crude oil: It rose to more than $15 per mcf in September 2005, immediately following Hurricane Rita, and then dropped below $5 per mcf during the summer of 2006. This wholesale price of natural gas was about $6.70 in early fall 2007.

Wholesale prices of crude oil, gasoline and its distillate products, and natural gas have at least doubled in the past several years. As an example of the trend in energy prices over the past decade, Figure 1 shows the variations in average (as opposed to spot) annual crude oil prices from January 1997 to July 2007. (The spot price of light sweet crude at the time this article was updated, for November 2007 delivery, was actually about $80 per barrel.)

The price for natural gas also has been erratic over the past decade but generally has increased, as shown in Figure 2.

Comparing Figures 1 and 2, it is apparent that natural gas prices have been even more erratic than those of crude oil. Natural gas prices are more severely affected by events like long, cold winters and natural disasters.

What effect have these increasing crude oil and natural gas prices had on thermal insulation markets? As predicted in the November 2003 Insulation Outlook article “The Impact of High Natural Gas Prices on the Mechanical Insulation Industry” (see www.insulation.org/articles/article.cfm?id=IO031102), the markets for mechanical insulation have grown dramatically and clearly will continue to grow in the future. Reasons for this include the following:

  • New construction in the electric power and oil industries, as well as retrofit of existing coal-fired power plants, have combined to make the mechanical insulation opportunities in the power sector the best they have been in more than 20 years.
  • Mechanical insulation contractors are enjoying a robust business in both the environmental retro-fit of existing coal-fired electric power plants and the construction of new ones.
  • Insulation opportunities in new natural gas turbine generators continue in spite of today’s much higher natural gas prices.
  • New construction projects in the Oil Sands area of northern Alberta, Canada, are huge. Collectively, they form perhaps the largest group of construction projects in any one geographic area in North America. All of the projects have an extensive quantity of new hot service piping and equipment that needs to be insulated.
  • The petrochemical industry, enjoying record revenue in the past few years, is undertaking extensive upgrades to existing facilities, as well as capacity expansions. Construction of a large new oil refinery—the first such new American refinery in some 35 years—is being planned on the U.S. Gulf Coast.
  • The mechanical insulation distributors, fabricators, and contractors along the U.S. Gulf Coast of Texas and Louisiana are enjoying a brisk business, as are those in northern Alberta near Fort McMurray—the “home base” for the Canadian Oil Sands development. Business should continue to be good there in the future as well.

With all of this new mechanical insulation activity—much of it driven by rapidly increasing prices for crude oil, crude oil products, and natural gas—it is logical to expect significant increases in the specified insulation thicknesses on various projects. It would make sense for thermal insulation thickness tables for hot service piping and equipment—the matrix tables with pipe temperatures across the top and pipe diameters down the side—to have been updated recently and to require at least a 50-percent increase in thicknesses from the requirements of the 1990s.

While energy prices have more than doubled in the past few years, there has not been a wholesale rewrite of the old pipe insulation thickness tables. When it comes to insulation thickness tables, the rule seems to have always been: “If it isn’t broke, don’t fix it!” However, the old adage does not necessarily hold true in this situation. The rest of this article explores how to select insulation thicknesses for piping and equipment, and takes an in-depth look at the mysterious relationship—or lack of relationship—between rising energy prices and specified insulation thicknesses.

Insulation Thickness Tables: A Closer Look

Different design firms and industrial facilities have their own insulation thickness tables for hot service piping and equipment. They may have several tables—one for each type of insulation approved for use at the facility. If a company has one facility located along the Gulf Coast and another near Chicago, the tables for a given type of insulation will probably be different in each location to account for differences in weather. There is no single correct insulation thickness table, even for a given type of insulation. For the purposes of this article, the petrochemical industry is a valid example. However, the information provided here is applicable to many industries and is not limited to petrochemical facilities.

Process Industry Practices (PIP) (Revision 1, 1999) for insulation represents a petrochemical industry cooperative effort. It contains 22 insulation thickness tables. For above-ambient service temperatures, there are tables for calcium silicate, cellular glass, fiberglass, mineral wool, expanded perlite, and polyisocyanurate. For each type of insulation, the following three tables are included: 1) an economic thickness table, 2) a table to limit the maximum surface temperature to 140°F, and 3) a table that gives the largest thickness of the two. Because of temperature limitations of the materials, the calcium silicate, mineral wool, and expanded perlite tables extend to 1,200°F; the cellular glass tables extend to 800°F; and the fiberglass tables extend to 850°F. The polyisocyanurate tables only extend up to 250°F. For each table, there is a thickness for each temperature column, based on 50-degree increments, for each standard pipe size between ½-inch iron pipe size (IPS) and 36-inch IPS, as well as for flat surfaces. These tables are good references because they are sometimes used by the petrochemical industry as thickness standards.

Design Information

The following specifications are for a facility in or around the U.S. Gulf Coast:

  • Average pipe temperature: 600°F
  • Average ambient temperature: 60°F
  • Average wind speed: 5 miles per hour (mph)
  • Average pipe size: 8-inch nominal pipe size (NPS)
  • Insulation type: Commercially available, preformed, mineral wool pipe insulation that meets the requirements of American Society for Testing and Materials (ASTM) C547 Type II and has the thermal conductivity data in Figure 4 (Table 1)
  • Metal-jacketing emissivity: 0.1 for oxidized aluminum jacketing

Based on this example, one can look at the four reasons for insulating to generate an insulation thickness table.

Process control. To determine a thickness using process control as the design criteria, usually some fluid temperature needs to be maintained. For a hot fluid being piped from point A to point B, the heat loss/unit pipe length in British thermal units per hour-lineal feet (Btu/hr-LF) would need to be kept to some maximum value. For a pipe length of 1,000 LF and a heat loss that must be limited to 300,000 Btu/hr over that length, the maximum allowable heat loss/unit length would be 300,000/1,000 = 300 Btu/hr-LF.* Inputting the above information into 3E Plus shows that a thickness of 2 inches is required to meet the condition that heat loss/unit length < 300 Btu/hr-LF. 

So, for process control, how would one generate an insulation thickness table using the above criteria for one pipe size at one temperature and a maximum allowable heat loss/unit length of 300 Btu/hr-LF? Well, one cannot—at least, not in any simple way. Each pipe size and temperature would need to be considered separately. The value could, however, be expressed in terms of a single value of heat loss/unit surface area of insulation. For this specific example, the equivalent heat loss/area would be 82.6 British thermal units per hour-square feet (Btu/hr-ft2).

Using this single value (rounded up to 85 Btu/hr-ft2 for simplicity), an insulation thickness table for pipe temperatures from 200°F to 800°F in 100-degree increments from ½-inch IPS to 36-inch IPS can be generated. 3E Plus conveniently has an option called Heat Flow Limitation that has an input box for the maximum allowable value (in this case, 85 Btu/hr-ft2). It seems simple to use just one design heat loss value for all pipe sizes and operating temperatures, but this approach leads to a major problem.

A fixed heat loss/insulation surface area is not likely to work for all processes at a facility. Each process line is a different length; diameter; and, perhaps, service temperature. Users must realize that for the above example, for each square foot of pipe area there are 1.24 square feet of insulation surface area at a thickness of 2 inches thick. For a thickness of 3 inches, that same pipe would have 1.71 square feet of insulation surface area for each square foot of pipe area.

If this seems confusing, that is because it is. The use of a single heat-loss limitation value for all pipe sizes and temperatures, expressed as heat loss/insulation surface area, may be easy mathematically and save the specifier lots of work. It also may save the facility owner money otherwise spent to pay an engineering company to generate insulation thicknesses for each pipe at the facility. However, that approach does not work because it does not consider the heat loss from each lineal foot or each lineal meter of pipe length, which is what process control requires. Therefore, using a single value of heat loss/insulation surface area is misleading and is basically a poor way for specifiers to generate insulation thickness tables.

Energy prices have not had any influence on the insulation thicknesses determined by process control limits. Natural gas prices could increase from $8 to $100 per mcf and the insulation thicknesses determined by process control limits would remain unchanged.

Personnel protection. Another common way of generating insulation thickness tables is to limit the insulation surface temperature to some value that will keep personnel from getting burned if they come in contact with the insulation surface (or the metal jacketing that covers the insulation). In many cases, 140°F is the specified maximum allowable surface temperature. The design conditions used are generally a warm summer day when the air temperature is high and the wind speed is low (conditions that increase the insulation surface temperature). For the above 8-inch IPS, 600°F pipe with preformed mineral wool pipe insulation, warmer, calmer conditions might be used. These could include an ambient temperature of 90°F and no wind, rather than an average ambient temperature of 60°F and average wind speed of 5 mph. For this specific case, 3E Plus can be used with Calculation Type: Personnel Protection. The design data in Figure 4 (Table 1), along with the 140°F maximum allowable surface temperature, also can be input.

The calculated insulation thickness using 3E Plus for these specific conditions is 3.5 inches. The specifier then can take each pipe diameter and temperature, run 3E Plus with these conditions and with this particular mineral wool pipe insulation, and generate a complete thickness table for all standard pipe sizes and service temperatures—perhaps from 200° to 1,200°F in 200-degree increments—in just a few hours.

By contrast, PIP recommends only 2.5 inches of mineral wool to limit the surface temperature to 140°F on a 600°F, 8-inch IPS pipe. Apparently, more lenient design conditions were used to generate PIP’s surface temperature limitation tables.

The cost of energy did not influence the thickness table based on personnel protection. Oil could increase to $200 per barrel and the thicknesses required for personnel protection would remain the same. The price of energy has nothing to do with selecting an insulation thickness for personnel protection.

Condensation control. On below-ambient-temperature pipes, the overriding concern in almost all applications is the prevention of surface condensation. Condensation control is important for thermal insulation design on below-ambient service temperatures. This article focuses on hot service piping and equipment, however, and does not consider condensation control.

Energy savings. Thermal insulation definitely saves energy and money. While process control, personnel protection, and condensation control can be confusing, energy savings is quite simple. The basic concept is to reduce heat loss (or heat gain) from a pipe or piece of equipment and thereby use less energy. To understand how energy savings determine insulation thicknesses, the concept of economic thickness must be explored. (See “Multiple Choice, Part 2” in the December issue.)

A Fresh Approach

What about existing insulation that is economically insufficient? To maintain a competitive advantage, process industries must adapt to the sudden rise in energy prices seen in this decade. The prospect of tearing off and disposing of existing insulation and jacketing that is in good condition so that new, thicker insulation can be installed clearly would not be cost-effective. In fact, that process would generate a lot of scrap that would cost even more money to remove and dispose of properly.

A more efficient and cost-effective solution is to wrap new insulation over the top of the existing system. Figure 3 illustrates this concept using an overwrap of 1 inch of a mineral wool pipe and tank insulation on top of the existing system consisting of metal-jacketed, 3-inch-thick, commercially available, preformed mineral wool pipe insulation. For the example of a 600°F, 8-inch IPS pipe in a 60°F ambient temperature, this would decrease the heat loss from 197 Btu/hr-LF to 161 Btu/hr-LF, an 18-percent reduction. An economic thickness analysis with results generated by 3E Plus concludes that 1 inch of the mineral wool pipe and tank insulation is the economic thickness for this insulation retrofit.

The Wrap-Up

Energy prices have increased dramatically in the past decade. To combat the high prices, thermal insulation for hot service piping and equipment is a cost-effective way of reducing heat loss. At today’s energy prices, thermal insulation on hot service piping and equipment typically has a payback of less than 1 month compared to uninsulated surfaces. The insulation thickness tables used by industry today typically were generated when energy prices were much lower. This raises the question, Why not revise the existing insulation thickness tables to reflect today’s increased energy costs?

For new construction, or for a total insulation retrofit of existing piping and equipment, specifiers and facility owners should discard old insulation thickness tables and generate new ones using current energy costs. Use of the old insulation thickness tables results in unnecessary waste of money for heating energy. Use of new insulation thickness tables, generated using economic thicknesses and resulting in greater insulation thicknesses, will result in greater energy efficiency and can be cost-effective.

For existing insulated piping and equipment, an economical and practical option is to retrofit the insulation system with an overwrap of mineral wool pipe and tank insulation with new metal jacketing. There is the practical advantage that this work could be executed on a flexible schedule to accommodate the availability of insulators to do the work.

The choice is the facility owners’ to make: They can either waste money on heating energy by using obsolete insulation thickness tables or take steps to improve the thermal efficiency of their insulated piping and equipment by generating new, up-to-date thickness tables. The time spent doing this will be offset by cost-effective energy savings both immediately and in the future.

* Additional engineering would be required to derive the assumed 300,000 Btu/hr-LF number, but that is beyond the scope of this article.

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Figure 4