Category: Knowledge

In the pursuit of energy efficiency and sustainability, the heating, ventilation, and air conditioning (HVAC) systems play a pivotal role. The demand for energy-efficient solutions is on the rise, proper insulation of HVAC systems becomes paramount. There are a range of products designed to optimise energy usage and reduce environmental impact. This article explores the importance of HVAC insulation and showcases some types of insulation materials.

What is a HVAC system?

HVAC stands for heating, ventilation, and air conditioning. It is a sophisticated network of equipment and components designed to regulate indoor environmental conditions in buildings. It encompasses heating, cooling, ventilation, and air quality control to maintain comfortable temperatures, humidity levels, and air circulation throughout various spaces. HVAC systems typically consist of furnaces or boilers for heating, air conditioners or heat pumps for cooling, ductwork for air distribution, fans for circulation, filters for air purification, and controls for system management.

The importance of HVAC insulation 

HVAC systems are essential for creating optimal indoor environments in residential, commercial, and industrial buildings, ensuring occupant comfort, health, and productivity. But they can also account for a significant portion of energy consumption in buildings. Inefficient insulation of HVAC systems can result in heat loss during the winter months and heat gain during the summer, leading to increased energy usage and higher utility bills. Additionally, poorly insulated HVAC ducts can contribute to air leakage and reduced indoor air quality.

Effective insulation not only improves energy efficiency but also enhances the overall performance and lifespan of HVAC systems. Insulating materials can be applied to ducts, pipes, and other HVAC components. By minimising heat transfer and air leakage, insulation helps maintain consistent temperatures, reduces the workload on HVAC equipment, and extends its operational life. Moreover, proper insulation can contribute to achieving green building certifications and compliance with energy efficiency regulations.

HVAC insulation criteria

When selecting insulation for your HVAC system, various factors must be taken into consideration to ensure optimal performance and longevity.

• Operating temperature: Ensure that the insulation can effectively withstand the temperature fluctuations experienced by the HVAC system it will be applied to.
• Moisture resistance: Select insulation with adequate moisture resistance to prevent the growth of mould and mildew, safeguarding both the system and indoor air quality.
• Fire resistance: Depending on the location of the HVAC system, prioritise insulation with appropriate fire resistance properties to enhance safety measures.
• Cost: Evaluate both the initial cost and potential long-term savings from improved energy efficiency when considering insulation options.
• Availability: Opt for insulation readily accessible in the market and straightforward to install, ensuring seamless integration into your HVAC setup.

Types of duct insulation

There are different types of duct insulation materials available, such as fibreglass, spray foam, and foam boards. Each of these options has its own advantages and disadvantages, depending on the characteristics of your HVAC system and your insulation needs. The type of duct insulation is determined by the insulation area, and the type of ducts. There are different types of insulation for different applications, such as ducts and pipings. Common types are:

Cellular glass

Cellular glass, commonly known as foam glass, has emerged as a recent entrant in the HVAC insulation realm, garnering attention for its impressive attributes. Notably, it boasts a high operational temperature threshold, superb moisture resistance, and exceptional fire resistance. Its versatility extends to its ease of installation and capacity to conform to confined spaces, rendering it well-suited for application in ductwork and piping systems.

PIR boards

Polyisocyanurate (PIR) boards are prized for their excellent thermal performance and durability in HVAC insulation. These rigid foam boards are lightweight yet robust, they’re easy to handle and install on rectangular ductwork. These boards are cut on site and secured to the ductwork using aluminium foil tape (Temfoil SA30) on all joints. Where necessary, for more dense insulation an adhesive or mechanical fix can be used.

Prefabricated slotted section boards

Circular ductwork often employs prefabricated slotted section boards for insulation. These panels are easily installed onto the pipework, with flexible cladding (such as Vapor-Fas™ 62-05) applied beforehand to provide weather protection. Vapor-Fas joint tape, also available in narrow rolls, is then utilised to seal the system, ensuring optimum thermal performance and energy efficiency.

Benefits of HVAC insulation 

By insulating HVAC systems, building owners and operators can benefit from:

• Improved energy efficiency: Insulation helps minimise heat transfer and air leakage, reducing energy consumption and lowering utility costs.
• Enhanced comfort: By maintaining consistent indoor temperatures, insulation solutions contribute to a more comfortable and productive indoor environment.
• Long-term durability: insulation with high-quality materials and construction ensure durability and reliability, resulting in lower maintenance requirements and extended equipment lifespan.

Conclusion

In conclusion, where energy efficiency and sustainability are top priorities, proper insulation of HVAC systems is essential. Insulation solutions offer a cost-effective way to optimise energy usage, improve indoor comfort, and extend the lifespan of HVAC equipment. By insulating HVAC projects, building owners and operators can achieve significant energy savings and lower carbon emissions.

A cryogenic insulation system consists of a combination of the following main components:

• Insulating material PIR foam
• Insulating material cellular glass
• Insulating material glass wool flakes for cryogenic applications
• Primary and secondary vapour barriers
• Flexible self-adhesive tapes and metal foils
• Contraction joints and associated protection system
• Vapour barrier coatings
• Sealant for cryogenic applications
• Metal jacketing, with metal strips and sealant for seam sealing

Insulation material – polyisocyanurate rigid foam (PIR)

For the properties of rigid polyisocyanurate foam, please refer to the minimum requirements summarised in CINI 2.7.01. The main requirements are specified below, otherwise CINI 2.7.01 is the minimum reference.

Composition according to ASTM C591

• Rigid Polyisocyanurate (PIR) foam, manufactured with CFC-/HCFC-free propellant.
• Foam structure: maximum closed cells (> 90% according to EN ISO 4590 – ASTM D2856).

Properties of rigid PIR foam

• Temperature range: from -200°C to +120°C,
• Specific gravity (EN ISO 845 – ASTM D1622): minimum 40 kg/m3 and maximum 52 kg/m3,
• Thermal conductivity coefficient for non-aged foam (EN 12667 – ASTM C177): max 0.021 W/mK at +20°C and max 0.016 W/mK at -160°C,
• Thermal conductivity coefficient for ageing degraded foam (value determined for dimensioning of thicknesses): 0.025 W/Mk for an average temperature of -65°C,
• Closed cells (EN ISO 4590 – ASTM D2856): more than 90%,
• Water absorption (ISO 2896 – ASTM D2842): max 5% by volume,
• Water vapour permeability (ASTM E96 Procedure A – ISO 1663): 30 (+/-10) g/(m2.24h) at 23°C and 85% relative humidity,
• Chloride content (ASTM C871): max 60 mg/kg.
• Minimum compressive strength (EN 826 – ASTM D1621): higher than (250 kPa and 200 kPa).
• Minimum tensile strength (ASTM D1623) higher than (420 kPa and 320 kPa),
• Dimensional stability (EN 1604): less than or equal to 1%,
• PH: 6 > 7,
• Foam should be protected from prolonged exposure to UV radiation.

Flammability and fire reaction classification

• Temperature index EN ISO 4589-3: above 390°C.
• Fire behaviour classification: category A2 or B according to NF EN 13501 (euro class – low flammability), fire reaction test requirements:
  • Category M1 according to NF P92 501;
  • Category B1/B2 according to DIN4102 (vertical burning).

Insulating material – Cellular glass

The properties of cellular glass are summarised in the minimum requirements of CINI 2.9.01. The main requirements are specified below.

Composition according to ASTM C552 or EN 14305

Cellular glass, without binder and composed of closed cells.

Properties of cellular glass

• Temperature range: -196°C to +430°C;
• Density (ASTM D1622 or EN 1602): 115 kg/m3;
• Thermal conductivity coefficient of plates (ASTM C177 or EN 12667): max 0.048 W/mK at +50°C and max 0.02 W/mK at -180°C;
• Thermal conductivity of shell panels (ASTM C177 or EN ISO 8497): max 0.052 W/mK at +50°C and max 0.022 W/mK at -180°C;
• Closed cells (EN ISO 4590 – ASTM D2856): 100%;
• Water vapour permeability (ASTM E96 Procedure A or EN 12086): max 0 ng / (Pa.s.m) at 23°C and 50% relative humidity;
• Compressive strength (ASTM C165 or EN 826): 500 kPa in all directions.
• Chloride content (ASTM C871 or EN 13468: ion chromatography): max 10 mg/kg;
• PH (ASTM C871 or EN 13468): between 7 and 10.5;

Insulating material – loose Mineral wool for cryogenic applications

The properties of mineral wool for cryogenic applications. Use reserved for contraction joints and specialist parts of the insulation system such as valves, flanges, etc:

• Loose stone/glass wool for cryogenic applications,
• Thermal conductivity coefficient between 0.017 and 0.022 W/ m.K at -170°C, to be specified in the contractor’s quotation,
• Acceptable temperature range of -200°C to +120°C, to be specified in the Contractor’s quotation,
• No organic binder,
• Density: to be specified in the Contractor’s quotation,
• Maximum compression in use: 50%,
• Minimum required fire behaviour: A2 (M0).

Primary vapour barrier

For the characteristics of the primary vapour barrier, refer to the minimum requirements summarised in section 4.4.21 of the CINI 1.3.02 data sheet and the CINI 1.3.53 data sheet. The main requirements are specified below:

• This primary vapour barrier consists of two layers of elastomeric coating, reinforced in the second layer by a fibreglass scrim fabric.

Regarding the coating used as vapour barrier:

• Solvent-based elastomeric coating according to CINI technical specification 3.2.03,
• Permissible temperature range -50°C to +100°C,
• Water vapour permeability, max 0.001 g/m2.h.mm Hg (according to ASTM E96 Procedure E),
• Chloride content (ASTM C871): max 90 ppm,
• Flame dispersion index (ASTM E84): less than 7.

With regard to the fibreglass scrim fabric:

• Glass fabric, type and version recommended by the coating supplier,
• Fabric and number of threads per length to be specified,
• Mass per unit area, in g/m2 to be specified,
• Minimum required fire behaviour: A2 (M0).

Secondary vapour barrier

For the characteristics of the secondary vapour barrier, refer to the minimum requirements summarised in CINI datasheet 3.3.10. The main requirements are specified below:

• Three-layer construction of polyester foil / aluminium foil / polyester film,
• Permissible temperature range of -60°C to +120°C,
• Water vapour permeability, max 10×10-6 g/m2.h.mm Hg (ASTM E96 Procedure E),
• Minimum thickness: 12 micron polyester film and 25 micron aluminium film, total thickness minimum 50 microns,
• Mass per unit area, greater than 100 g per m2,
• Tensile strength, min. 100 MPa,
• Tear strength (Elmendorf), min. 400 g/mm.

Flexible self-adhesive tapes and metal foils

Glass fibre reinforced tape

The first layer of rigid PIR foam, on the pipe side, and any intermediate layers of the same foam should be fixed with tape as referred to in Technical Specification CINI 2.25.01 (chapter 2.4 “Synthetic tape”). The main requirements are specified below:

• Tape of synthetic material reinforced with glass fibres,
• Permissible temperature range of -120°C to +120°C,
• Minimum width 38 mm,
• Minimum thickness 0.14 mm,
• Minimum adhesive strength 200 gr / 25 mm².

Steel strapping and fasteners

The outer layer of rigid PIR foam, the metal cladding and the housing of valves are strapped by means of steel straps and associated clamps. Both components are made of austenitic stainless steel, partly in accordance with the technical specification of CINI 2.25.01 (section 2.1 “Tape on rolls of 10-20 kg”). The main requirements are specified below:

• Austenitic annealed stainless steel, Cr-Ni 18-10 grade (e.g. ASTM A167 TP 304),
• Minimum width and thickness: 13 mm x 0.5 mm for DN 400 and smaller,
• Minimum width and thickness: 19 mm x 0.5 mm for DN 400 and larger,
• Clamps of annealed austenitic stainless steel, of equal thickness guaranteeing the same live load as the steel strap, of a type corresponding to the type of steel strap used.

Contraction joint and associated protection system

The Contraction joint is made of mineral wool for cryogenic applications and is listed in technical specifications CINI 5.1.06 (“Cold insulation – Contraction joints”) and CINI 3.25.01 – 2.1 (Auxiliary materials for cold insulation).

Two types of protection of contraction joints, depending on their location in the cold insulation system:

• The contraction joints of the inner and intermediate layers of rigid foam are covered and protected by a secondary vapour barrier as described earlier.
• The contraction joints of the outer layer of rigid foam are covered and protected by a corrugated layer of butyl rubber 1 mm thick, in accordance with ISO 188 (CINI 3.25.01 – 2.1). This butyl rubber protection of the joint is secured on both sides of the shrinkage zone with steel tape, as described in the previous paragraph.

Vapour stop coating – end pieces and terminations

The characteristics of the “Vapour Stop” coating used for compartmentation and end pieces are based on the minimum requirements summarised in the CINI data sheet 3.2.09 (“Two-component sealing”), with an additional reinforcement of lattice fabric made of glass fibre. The main requirements are specified below:

Cryogenic, two-component elastomeric coating for use as a coating for seals and barriers:

• Two-component” elastomeric coating, according to CINI technical specification 3.2.09,
• Permissible temperature range of -196°C to +120°C,
• Water vapour permeability, max 0.001 g/m2.h.mm Hg (ASTM E96 Procedure E),
• Average solids content (ASTM D1644): 55% by volume,
• Chloride content (ASTM C871): max 90 ppm,
• Flash point (ASTM D93): 23°C,
• Two layers of coating when used as a vapour barrier and three layers when used as a Vapour Stop.

Additional reinforcement for Vapour Stops:

• Glass fabric, type and version recommended by the coating supplier,
• Fabric and number of threads per length to be specified,
• Mass per unit area, in g/m2 to be specified,
• Minimum required fire behaviour: A2 (M0).

The vapour control coating chosen is uniform for the entire system and thus allows all joints for the permissible temperature range (-196°C to +120°C) to be finished with a single cryogenic coating. The use of a second type for the temperature range (-50°C to +120°C) is not acceptable. 

Cryogenic joint sealant

The properties of the joint sealant used to fill the longitudinal and circumferential seams of the various rigid foam elements and vapour control coatings meet the minimum requirements summarised in CINI data sheet 3.2.09 (“Two-component sealant”). The main requirements are specified below:

• Cryogenic joint sealant of the “two-component elastomer” type, in accordance with CINI Technical Specification 3.2.09,
• Permissible temperature range of -196°C to +120°C,
• Water vapour permeability, max 0.001 g/m2.h.mm Hg according to (ASTM E96 Procedure E),
• Average solids content (ASTM D1644): 55% by volume,
• Chloride content (ASTM C871): max 90 ppm,
• Flash point (ASTM D93): 23°C. 

External protective metal cladding

The characteristics of the protective metal cladding, of the type “steel plate coated with pure aluminium, known as type 2 and pre-painted”, are referred to the minimum requirements summarised in data sheet CINI 3.1.02. The main requirements are specified below:

• Steel sheet coated on both sides with pure aluminium, minimum thickness 50 microns,
• Type 2, i.e. “pure aluminium coated”, with 300 g/m² per side,
• Minimum thickness of cladding:
  • 0.55 mm for cold insulation systems with an outer diameter of less than 400 mm;
  • 0.8 mm for cold insulation systems with an outer diameter of more than 400 mm (according to the recommendations of DTU No 67.1);
  • 1 mm for valve boxes and accessories;
• Standard NF A36.345 – Iron and steel products – Steel sheets fully coated with aluminium – Sheets and coils – Thickness 0.5 mm to 3 mm – Maximum width 1540 mm,
• CINI Standard 3.1.02 (Chemical properties according to (ASTM A463M), Table 2 Commercial grade – Corrosion resistance according to (ASTM A463M) – Minimum width 500 mm),
• Special requirements and deviations from the properties of the metal cladding may be specified as “alternatives” in the Contractor’s quotation and submitted to the Client for approval.

Questions or contact?

If you have technical or commercial questions about the components of a cryogenic insulation system or any of our other solutions, please contact us. We will be happy to work with you to find the most efficient insulation solution for your application.

Thermal insulation protects installations from heat loss and/or heat absorption. It ensures that no energy is lost from industrial installations such as pipes and fittings in boiler rooms. Saving energy, also caring for the environment and CO² reduction, is a topic that has been around for decades within the industry, but the energy crisis anno 2022 makes insulation more topical again than ever. Different materials exist for thermal insulation. In this article, we will further discuss the origins of thermal insulation, the reasons for insulation and what products are available for industrial thermal insulation.

The origins of industrial thermal insulation

Thermal insulation has been used since the late 18^th century, not so much for energy conservation, but to protect personnel from being burned by hot parts. After WWII, new types of insulation materials such as stone wool came along, which were also widely produced. In 1973, industrial thermal insulation received a huge boost from the oil crisis. Due to the scarcity and high fuel prices, insulation in the (petro)chemical industry became additional and more widespread.

What is industrial thermal insulation?

Industrial thermal insulation is characterised by the variety of technical requirements placed on the materials. But also because of the wide temperature range from -200 to 1,200°C, combined with extreme environments where the insulation is applied, it differs from architectural insulation. Industrial insulation is the insulation of technical, mechanical installations and structures. Usually these are complex installations of a lot of piping combined with tanks, heat exchangers, distillation columns and vessels.

Applications for industrial insulation include:

1. (Petro)chemical industry
2. Energy producing industry
3. Offshore
4. Shipbuilding
5. HVAC (Heating Ventilation & Air Conditioning) installations

Why industrial thermal insulation?

The main reason for thermal insulation is to prevent unnecessary energy loss. An uninsulated piping system loses heat unnecessarily, leading to higher energy costs. In practice, pipes are often insulated, but fittings such as valves are not. Thermal insulation of these fittings not only saves energy, but due to high gas prices, the payback time is also very short. In the image below, a thermal image shows the difference between insulated fittings and fittings without insulation.

Industrial thermal insulation of fittings can be done easily and quickly with Temket insulation mattresses. These insulation mattresses are made of Temtex™ glass fabrics that are heat-resistant. Developed especially for utilities, this range of insulation mattresses can be installed without technical knowledge. The mattresses are a flexible solution for insulating fittings, valves and pumps and can be easily installed with the Velcro closure. The insulation mattresses come in universal versions, but can also be produced in any shape and size up to a temperature resistance of 1050°C.

Regulations on thermal insulation

Since 2019, the Netherlands has had an information duty around energy saving. Saving energy is important because everything we do not use does not need to be generated, imported or paid for. Companies and organisations, including EU ETS and mandatory permit companies, can make a substantial contribution to this by taking energy-saving measures from the Recognised Energy Efficiency Measures List (EML) with a payback period of 5 years or less. Examples include insulating non-insulated parts such as fittings or using LED lighting. Besides the information obligation, there is also a research obligation with an energy report. Part of this is an insulation scan. This involves an inventory of insulated pipes and fittings plus a specification of savings measures.

Subsidy opportunities for industrial thermal insulation

With the EML, the energy saving obligation can be met. Energy-saving measures ultimately lead to lower expenses, but this requires an investment first. Fortunately, there are several subsidy options such as the Energy Investment Allowance (EIA) for measures from the Energy List 2022, the Sustainable Energy Investment Subsidy (ISDE) for heat pumps, solar panels, etc. and the Accelerated Climate Investment (VEKI) for measures with a payback period of more than 5 years.

Choice of insulation type

Important terms in industrial insulation are reliability, availability and safety, but durability and energy saving have also become increasingly important in recent years. The reason for insulation determines the right type of insulation material and finishing material.

Some of the reasons are:

• Thermal (cold or hot)
• Safety (fire safety, health etc.)
• Acoustic

Each insulation material has unique properties, which are important when choosing the type of insulation, e.g. its insulating capacity. This is also known as thermal resistance and is indicated by the Lambda value. Another important aspect is the degree of flammability. Most industrial plants are critical industrial processes where safety for people and the environment is the highest priority.

Conditions of use of thermal insulation

Every insulation material has processing instructions, which determine its final quality and long-term use. 2K pu foam should be processed between 23 and 27 °C. When processing under lower temperature conditions, the 2K PU foam insulation set will first have to be brought to this temperature with, for example, heat blankets. In addition, wearing necessary personal protective equipment such as a mouth mask is required in most cases when using e.g. Thermat glass fibre insulation blankets and Superwool insulation blankets.

Maintenance of insulated pipes

In due course, inspection and maintenance of the components of the insulated pipes and installations is needed. During maintenance, part or all of the insulation often needs to be removed. With the use of Temket’s insulation mattresses, this is not an issue. With the removable mattresses, you not only have good insulation, but by means of the Velcro closure, all important elements such as fittings and pumps also remain accessible at all times. This also makes them easy to clean and reusable.

Corrosion Under Insulation

In addition, for industrial plants equipped with thermal insulation, it is important and sometimes required by law to check them regularly for CUI (Corrosion Under Insulation). This hidden defect is often difficult to predict and where good insulation plays a major role. Good insulation means an insulation system that allows moisture that has penetrated in an undesirable way to escape. For instance, by means of a drain plug. For some inspections, it is more convenient to install an inspection plug instead of removing parts of the insulation.

Various coatings for thermal insulation are available that also protect against solvent attack in chemical-resistant finishes.

Specialist in insulation solutions

Temati has been a specialist in insulation solutions for 60 years and is happy to think with you for the most efficient insulation in your situation. Contact one of our specialists for advice or a quotation.

In a variety of applications, 2k pu foam, also known as PU foam, is the most effective form of thermal insulation. PUR is short for polyurethane and has a very high insulation value. 2K pu foam has maximum airtightness, ensuring optimal sealing of nooks and crannies of the space to be insulated. In addition, foam sealant is relatively quick and easy to apply as insulation. In this article, we will take a closer look at insulating with polyurethane foam. You can read exactly what foam sealant is and how it works in our other article on the properties of PU foam.

Sprayable PU foam

PU foam insulation is always applied as a liquid after which it cures. This has the advantage that the PU foam gets into all nooks and crannies, thus sealing the space perfectly. Applying 2k sprayable PU foam can be done with different nozzles, depending on the application. A cone-nozzle is ideal for filling and injecting, while a spray-nozzle atomises the insulation material onto the surface. Sprayed PU is applied under high pressure after which it cures slowly or quickly, depending on the type of foam.

PUR mouldings

Besides sprayed PUR, it is also possible to use PUR insulation boards or moulded parts. These are cut to size and thickness in the factory from a large block of cured PU foam. The insulation value is the same as with sprayable PU foam, but in-situ foam works faster because you don’t have to measure everything in advance.

Advantages PU foam insulation

• The insulation foam cures quickly
• 2-component foam has a high insulation value
• Polyurethane foam insulation ensures perfect airtightness
• Applicable on surfaces with irregular shapes and indentations
• With sprayable pu foam, there is no need to measure everything first
• Lightweight but provides structural support
• Little to no waste

PU foam adheres firmly to most surfaces

With a foam gun, sprayable PU foam can be applied in a dosed manner to walls, ceilings, roofs and in cracks, among others. Polyurethane foam adheres to many building materials such as wood, metals and concrete. But also to plastics such as polyester, PVC and Styrofoam. It is a widely used insulation material in industry for good reason.

Polyurethane foam as insulation material

PU is a firm and dense foam that insulates well. This is due to the mass of closed cells that make up foam sealant. It holds dry air and it is this dry, stagnant air that ensures good insulation. Thanks to its high density, it not only insulates but also dampens sound. It also fills spaces, keeps odour and smoke out and provides additional structural support. Moreover, PU foam insulation resists temperatures from -120°C to 100°C.

Lambda value PU foam

An important criterion for the effectiveness of PU foam insulation is the Lambda value. This insulation value is an important measure and shows how much heat is lost through the PU foam insulation. The lower the value is, the better the insulation. This value depends on the layer thickness, but in general, polyurethane foam has a very high lambda value: 0.026 W/mK. Compared to other insulation materials such as glass wool (0.040 W/mK) and foam concrete (0.350 W/mK), this is a lot lower.

Sprayable pu foam is not only for insulating

However, foam sealant is not only used to insulate in industry, but is also used in many other applications. For instance, artists and builders of sets and floats also buy pu foam. They make light, yet sturdy shapes with the 2k pu foam. This is because cured polyurethane foam can easily be cut and modelled into the most complicated shapes.

Would you also like to buy PU foam for insulation?

Contact one of our specialists for advice or a quote. They are always at your service and together they will find the best insulation solution for your project.

Foam sealant is also called pu foam, pur or insulation foam. It is used for all kinds of applications including insulating walls, as well as sealing and filling gaps and cracks in insulation. What exactly is PU foam sealant, what types are there and how does it work? You can read all about it in this article.

• 1k or 2k pu foam
• Froth-Pak sprayable PU foam
• The difference between the three types of foam
• How does foam sealant work?
• Different nozzles
• Conditions of use
• Why maintenance is important
• How to remove PU foam
• Demonstration or advice

1k or 2k PU foam

You can buy foam sealant as one-component foam and two-component foam. The difference here is in how fast the foam cures. 1-component PU foam cures because it makes contact with moisture from the air or the substrate and is relatively slow. With 2-component PU foam, a hardener is added, which cures without the need for moisture. You will also notice this difference when cutting the foam sealant. With 2k pu foam the inside is also fully cured while with 1k pu foam the inside is still soft.

The difference between the three types of foam sealant

The Slow Rise is especially important when injecting polyurethane foam, also known as in-situ foams. This gives the foam time to reach all holes and corners before it cures. Quick Rise is often used on walls so that one can work through quickly. The High Density PU-foam has a higher density per m3 and is specially developed for applications where this density of 40 – 45 kg/m3 is required.

How does foam sealant work?

The 2k pu foam kit consists of two disposable tanks of 6kg or 20kg per component, which are pressurised, containing separately a foamer and a hardener. A hose set is connected to this, which is connected to a PU foam gun. When the tanks are opened and the sprayer is squeezed, foaming begins. No experience with sprayable PU foam? We also provide on-site explanations and demonstrations, please contact our technical specialists.

Various nozzles for sprayable PU foam

The nozzle, which is clicked onto the foam gun, has a mixing chamber. This is where the two components meet and ensure even distribution before being sprayed onto the product. When the foam and hardener are mixed, a chemical reaction occurs, causing the polyurethane foam to first increase in volume, or rise, and then cure.

Depending on the application, there are different nozzles. The cone nozzle is an all-round nozzle that ensures even distribution and is ideal for in-situ foaming. The spray nozzle, on the other hand, is suitable for spraying surfaces. When you stop foaming, the spray nozzle should be replaced after about 30 seconds because the foam then starts to harden. It is therefore important to prepare as much as possible before you start foaming.

Conditions of use 2k pu foam

Applying PU foam insulation is not difficult, but you need to take a few things into account. For optimum efficiency and best quality, it is important that the foam set is at temperature during use. A good usage temperature is between 23 and 27°C degrees. This can be done by placing the kit in a heat cabinet or with heat ribbons around it. The better the foam kit is at temperature, the higher the efficiency.

Why foam sealant maintenance is important

Maintenance is very important with PU foam insulation. Not only cleaning after use, but also regular flushing of the hose set contributes to a longer life. When this is not done, crystallisation occurs, causing the system to block. In addition, it can cause the mixing ratio to be incorrect, which also results in poor quality foam insulation.

Contact us for advice or a demonstration

Do you have questions about using 2k PU foam or need advice on your insulation project? Our specialists are at your service and take all the time to give your employees training and explanations where they can also foam themselves. Together we look at the best way to make your insulation project a success!