Pipe Insulation is thermal or acoustic insulation used on pipework.
Where pipes operate at below-ambient temperatures, the potential exists for water vapour to condense on the pipe surface. Moisture is known to contribute towards many different types of corrosion, so preventing the formation of condensation on pipework is usually considered important.
Pipe insulation can prevent condensation forming, as the surface temperature of the insulation will vary from the surface temperature of the pipe. Condensation will not occur, provided that (a) the insulation surface is above the dewpoint temperature of the air; and (b) the insulation incorporates some form of water-vapour barrier or retarder that prevents water vapour from passing through the insulation to form on the pipe surface.
Industrial Pipe freezing
Since some water pipes are located either outside or in unheated areas where the ambient temperature may occasionally drop below the freezing point of water, any water in the pipework may potentially freeze. When water freezes, it expands due to negative thermal expansion, and this expansion can cause failure of a pipe system in any one of a number of ways.
Pipe insulation cannot prevent the freezing of standing water in pipework, but it can increase the time required for freezing to occur—thereby reducing the risk of the water in the pipes freezing. For this reason, it is recommended to insulate pipework at risk of freezing, and local water-supply regulations may require pipe insulation be applied to pipework to reduce the risk of pipe freezing.
For a given length, a smaller-bore pipe holds a smaller volume of water than a larger-bore pipe, and therefore water in a smaller-bore pipe will freeze more easily (and more quickly) than water in a larger-bore pipe (presuming equivalent environments). Since smaller-bore pipes present a greater risk of freezing, insulation is typically used in combination with alternative methods of freeze prevention (e.g., modulating trace heating cable, or ensuring a consistent flow of water through the pipe).
Industrial Energy saving
Since pipework can operate at temperatures far removed from the ambient temperature, and the rate of heat flow from a pipe is related to the temperature differential between the pipe and the surrounding ambient air, heat flow from pipework can be considerable. In many situations, this heat flow is undesirable. The application of thermal pipe insulation introduces thermal resistance and reduces the heat flow.
Thicknesses of thermal pipe insulation used for saving energy vary, but as a general rule, pipes operating at more-extreme temperatures exhibit a greater heat flow and larger thicknesses are applied due to the greater potential savings.
The location of pipework also influences the selection of insulation thickness. For instance, in some circumstances, heating pipework within a well-insulated building might not require insulation, as the heat that’s “lost” (i.e., the heat that flows from the pipe to the surrounding air) may be considered “useful” for heating the building, as such “lost” heat would be effectively trapped by the structural insulation anyway. Conversely, such pipework may be insulated to prevent overheating or unnecessary cooling in the rooms through which it passes.
Industrial Protection against extreme temperatures
Where pipework is operating at extremely high or low temperatures, the potential exists for injury to occur should any person come into physical contact with the pipe surface. The threshold for human pain varies, but several international standards set recommended touch temperature limits.
Since the surface temperature of insulation varies from the temperature of the pipe surface, typically such that the insulation surface has a “less extreme” temperature, pipe insulation can be used to bring surface touch temperatures into a safe range.
Industrial Control of noise
Pipework can operate as a conduit for noise to travel from one part of a building to another (a typical example of this can be seen with waste-water pipework routed within a building). Acoustic insulation can prevent this noise transfer by acting to damp the pipe wall and performing an acoustic decoupling function wherever the pipe passes through a fixed wall or floor and wherever the pipe is mechanically fixed.
Pipework can also radiate mechanical noise. In such circumstances, the breakout of noise from the pipe wall can be achieved by acoustic insulation incorporating a high-density sound barrier.
Industrial Factors influencing performance
The relative performance of different pipe insulation on any given application can be influenced by many factors. The principle factors are:
- Thermal conductivity (“k” or “λ” value)
- Surface emissivity (“ε” value)
- Water-vapour resistance (“μ” value)
- Insulation thickness
Other factors, such as the level of moisture content and the opening of joints, can influence the overall performance of pipe insulation. Many of these factors are listed in the international standard EN ISO 23993.
Pipe insulation materials come in a large variety of forms, but most materials fall into one of the following categories.
Industrial Mineral wool
Mineral wools, including rock and slag wools, are inorganic strands of mineral fibre bonded together using organic binders. Mineral wools are capable of operating at high temperatures and exhibit good fire performance ratings when tested.
Mineral wools are used on all types of pipework, particularly industrial pipework operating at higher temperatures.
Industrial Glass wool
Glass wool is a high-temperature fibrous insulation material, similar to mineral wool, where inorganic strands of glass fibre are bound together using a binder.
As with other forms of mineral wool, glass-wool insulation can be used for thermal and acoustic applications.
Industrial Flexible elastomeric foams
These are flexible, closed-cell, rubber foams based on NBR or EPDM rubber. Flexible elastomeric foams exhibit such a high resistance to the passage of water vapour that they do not generally require additional water-vapour barriers. Such high vapour resistance, combined with the high surface emissivity of rubber, allows flexible elastomeric foams to prevent surface condensation formation with comparatively small thicknesses.
As a result, flexible elastomeric foams are widely used on refrigeration and air-conditioning pipework. Flexible elastomeric foams are also used on heating and hot-water systems.
Industrial Rigid foam
Pipe insulation made from rigid Phenolic, PIR, or PUR foam insulation is common in some countries. Rigid-foam insulation has minimal acoustic performance but can exhibit low thermal-conductivity values of 0.021 W/(m·K) or lower, allowing energy-saving legislation to be met whilst using reduced insulation thicknessess.
Polyethylene is a semi-flexible plastic foamed insulation that is widely used to prevent freezing of domestic water supply pipes and to reduce heat loss from domestic heating pipes.
The fire performance of Polyethylene usually prohibits its use in commercial buildings.
Silica Aerogel insulation has the lowest thermal conductivity of any commercially produced insulation. Although no manufacturer currently manufactures Aerogel pipe sections, it is possible to wrap Aerogel blanket around pipework, allowing it to function as pipe insulation.
The usage of Aerogel for pipe insulation is currently limited.
FIBERGLASS PIPE INSULATION
Fiberglass pipe insulation offers the widest range of uses the most cost effective choice of insulating mechanical systems.
- Fiberglass pipe insulation is jacketed with self sealing all service (ASJ) vapor retarder jacket.
- Moisture resistance assures stable high R-value of 4.35 per inch
- Fiberglass pipe insulations are molded of heavy density resin bonded inorganic glass fibers
- Insulation for hot, cold, concealed and exposed piping operating at temperatures from 0° F (-18° C to 850° F 454° C) in commercial buildings, industrial facilities and process or power plants
- SSL II Positive Closure System
- Jacket and lap shipped adhered
- Fiberglass pipe insulation has excellent thermal performance
- Meets Model Code fire ratings
Calcium Silicate Pipe and Block Insulation – Thermo-12®
Calcium Silicate Insulatio – Thermo-12® is a molded, high temperature, abuse-resistant pipe and block insulation with exceptional structural strength, composed of hydrous calcium silicate for use on systems operating up to 1200°F (649°C).
The gold color of Thermo-12® calcium silicate pipe & block insulation provides positive identification that it is asbestos-free. Calcium Silicate Insulation – Thermo-12® meets or exceeds the physical property requirements of ASTM C 533, Type I.
- Calcium Silicate Insulation has superior resistance to breakage and physical abuse.
- Because of its strength, low thermal conductivity and durability, Thermo-12® calcium silicate pipe and block insulation is the preferred product for application on high temperature piping and equipment.
- Calcium Silicate Pipe & Block insulation is recommended for use in the petrochemical and power generation industries.
Polyisocyanurate Foam Insulation – Trymer™ 2000 XP
TRYMER™ polyisocyanurate pipe insulation is a closed-cell, high-performance insulation for pipe, vessel, equipment and duct applications. ITW Insulation Systems offers a complete line of TRYMER pipe insulation products in a selection of densities and compressive strengths. TRYMER pipe insulation features one of the lowest ambient k-factors among all pipe insulations: 0.19 BTU · in/hr · ft2 · °F at 75°F mean temperature (0.027 W/m · °C at 24°C) and can be used over a broad temperature range from -297°F to 300°F (-183°C to 148°C).
Applications for Trymer 2000 XP polyisocyanurate foam insulation include:
- Industrial pipe insulation, including elbows and fittings
- Commercial chilled water insulation
- Tank and vessel insulation
- Core material for architectural and structural panels
- Insulation for shipping containers, trucks or railcars
- Core material for factory built panelized constructions
- Flat or tapered board stock for roof insulation
Foamglas® Pipe & Block Insulation by Pittsburgh Corning
Pittsburgh Corning’s FOAMGLAS® pipe and block insulation is a lightweight, rigid insulating material composed of millions of completely sealed glass cells, each an insulating space.
Foamglas pipe insulation’s all-glass, closed-cell structure provides an unmatched combination of physical properties, it is impermiable to moisture in any form, cannot burn and it is non-combustible. Foamglas pipe and block insulation is used most frequently in applications involving process piping, tanks, vessels and equipment which are most commonly used by the gas processing, refining, petrochemical and specialty chemical industries. Temperatures from -450°F to +900°F (-268°C to +482°C).
- Low temperature pipe, equipment, tanks and vessels
- Medium and high temperature pipes and equipment
- Hot oil and hot asphalt storage tanks
- Heat transfer fluid systems
- Hydrocarbon processing systems
- Chemical processing systems
- Above ground and underground steam and chilled water piping
- Commercial and institutional piping and ductwork
FOAMGLAS® insulation is:
- Resistant to water in both liquid and vapor forms
- Non-corrosive and will not support corrosion
- Non-combustible – will not absorb flammable liquids or vapors – cannot burn
- Resistant to most industrial reagents
- Dimensionally stable under a variety of temperature and humidity conditions
- A material with superior compressive strength
- Foamglas pipe insulation is resistant to vermin and microbes
- Fiber, CFC and HCFC free
Mineral Wool Pipe Insulation
Mineral wool pipe insulation is made from basalt rock and steel slag. These rigid pipe sections are strong, preformed mineral wool insulation with excellent thermal performance.
Mineral wool pipe insulation is a non-combustible product with a melting point of approximately 2150°F (1177°C), which gives it excellent fire resistance properties. Mineral wool is a water repellent yet vapor permeable material that is ideal for steam and process pipe systems operating at temperatures up to 1200°F (650°C), where energy conservation, personnel protection and fire control are concerns.
Benefits of Mineral Wool Pipe Insulation:
- Provides excellent thermal insulation performance for mechanical, power and process piping systems operating with continuous surface temperatures from sub-ambient to 1200°F (649°C).
- Mineral wool molded pipe insulation is easily fabricated, cutting cleanly and easily with a knife
- Good compressive strength
- Lightweight, low dust
- Good physical properties
AP/ ARMAFLEX PIPE INSULATION (TUBE)
AP/ Armaflex Pipe Insulation is a flexible thermal insulation made from Elastomeric foam based on synthetic rubber (Elastomer).
- Superior condensation control
- Excellent for retarding heat gain
- Dust free, fiber free, closed cell
The expanded closed-cell structure of AP/ Armaflex Pipe Insulation makes it an efficient insulation. It is manufactured without the use of CFC’s, HFC’s or HCFC’s. It is also formaldehyde free, low VOCs, fiber free, dust free and resists mold and mildew.
AP/ Armaflex Pipe Insulation is used to retard heat gain and control condensation drip from chilled water and refrigeration systems. It also efficiently reduces heat flow for hot-water plumbing and liquid-heating and dual temperature piping. The recommended temperature usage range for AP/ Armaflex Pipe Insulation is -297°F to +220°F (-183°C to +105°C).
For use on cold pipes, AP/ Armaflex Pipe Insulation thicknesses have been calculated to control condensation on the insulation outer surface, as shown in the table of thickness recommendations.
Resistance to Moisture Vapor Flow
The closed-cell structure of AP/ Armaflex prevents moisture from wicking and makes it an efficient insulation. AP/Armaflex normally requires no supplemental vapor-retarder protection. Additional vapor-retarder protection may be necessary for AP/ Armaflex when installed on very-low-temperature piping or where exposed to continually high humidity conditions.
Perlite Insulation – Temperlite® 1200° Thermal Insulation
Temperlite® 1200° Perlite Thermal Insulation is a rigid, high temperature, water resistant molded perlite thermal insulation available in either block, pipe or molded fitting form. The product is a light gray material with dark heat stabilized flecks throughout the product for easy identification as an insulation which does not contain asbestos.
Temperlite® 1200° Perlite Thermal Insulation is outstanding for its moisture, corrosion, and fire resistance. It exhibits excellent thermal performance and maintenance of integrity under extreme heat conditions up to 1200° F, and it combines the strength and rigidity needed to withstand installation abuses with an ease of fabrication in the field that maximizes fabrication equipment life.
Features and Benefits:
Moisture Resistance: At temperatures up to 600° F, Temperlite® 1200° Perlite insulation is extremely resistant to water absorption. Mechanical strength and thermal performance are preserving and the insulation will not act as a reservoir for jacket corrosion as is common with many other rigid insulations.
Corrosion Resistance: Because Temperlite® 1200° Perlite insulation is high in silicates and non-wicking, it will, not cause or promote stress corrosion cracking of austenitic stainless steel.
Thermal Performance: Temperlite® 1200° Perlite insulation provides excellent thermal insulating properties throughout its full range of use. This thermal efficiency results in reliable temperature control for critical process operations.
Fire Resistance: Temperlite® 1200° Perlite insulation will not burn or carry flame. It has a flame spread of zero and smoke developed of zero when tested per ASTM E 84.
Heat Stability: Unlike some other rigid insulation, Temperlite® 1200° Perlite insulation will maintain its integrity and insulating efficiency even under conditions of soaking heat up to its full 1200° F recommended operating range.
Rigidity: Temperlite® 1200° Perlite insulation is designed and manufactured to provide strength required to withstand personnel traffic and other common installation and application abuses.
Ease of fabrication: Temperlite® 1200° Perlite insulation cuts easily and cleanly, minimizing fabrication time in the field and prolonging fabrication equipment life.
XPS – Extruded Polystyrene Pipe Insulation (Styrofoam)
In demanding cold-service applications, no other insulating material can equal the performance of XPS Extruded Polystyrene pipe insulation (Styrofoam). The rigid, closed-cell structure of Extruded Polystyrene pipe insulation (Styrofoam) gives it high compressive strength, low friability, and excellent resistance to water and water absorption from freeze-thaw cycling. This allows it to maintain its superior performance over long periods of time.
XPS Extruded Polystyrene (Styrofoam) pipe insulation is nondusting and nonirritating, and is not a known nutrient source for mold and mildew. It is manufactured in thick seamless buns that easily accommodate common pipe sizes, which reduces or eliminates the need to bond layers of insulation together prior to fabrication.
Service temperature range: -297°F to 165°F (-183°C to +74°C).
XPS Extruded Polystyrene Pipe Insulation (Styrofoam) features:
- Excellent water resistance (to both liquid and vapor)
- Good thermal efficiency – low k-factor (high R-value)
- Closed-cell and non-fibrous structure that does not wick water and is not a known source for mold and mildew
- Good dimensional stability
- Fabrication and installation ease
- Non-dusting, clean surface
- Low initial and life-cycle cost
- Long service life
Tubolit Self Seal Polyethylene Pipe Insulation
Tubolit Self Seal Polyethylene Pipe Insulation by Armacell is a high quality CFC and HCFC free flexible closed cell polyethylene pipe insulation. Tubolit SS polyethylene pipe insulation is particularly effective for the thermal insulation of heating and plumbing pipe work for energy conservation and frost protection. It is available pre-glued on both sides of the seam in the most frequently specified pipe sizes and thicknesses. Tubolit SS polyethylene pipe insulation is expanded without the use of CFC’s, HFC’s or HCFC’s. It is also formaldehyde free, low VOCs, fiber free, dust free and resists mold and mildew.
Tubolit SS polyethylene pipe insulation is recommended for use on lines operating from 0° F (-17°C) to 180° F (82°C). It effectively reduces heat loss on hot-water plumbing and heat gain on cold water plumbing systems.
- Self-seal for quick installation
- Durable polyethylene insulation
- Saves energy, reduces noise
- Closed cell foam