Tommaso Gatto

Anyone who works with fabric expansion joints knows full well that a poorly designed component results in higher maintenance costs and plant downtime. What few people realize is that avoiding all of this requires meticulous groundwork.

A textile expansion joint cannot be treated like a catalog item, chosen arbitrarily and installed without a specific design. A meticulous process is required, in which every decision is tailored to the actual conditions of the plant. At New Componit, we’ve been working this way for forty years and every expansion joint we produce is the result of exactly that process.

Data come before the material

It all starts with gathering operational information: operating temperature, pressure, movements, flange geometry and the possible presence of chemicals or corrosive agents. This step influences every subsequent decision and we devote a great deal of attention to it.

An expansion joint operating at 400°C on a flue gas duct has completely different requirements than one installed on a fan or on the exhaust of a gas turbine.  From the outside, they might look almost identical, but designing them the same way means ignoring the actual conditions under which they will have to operate. Understanding the context before choosing the material is what determines whether the coupling will last over time or degrade sooner than expected.

From material selection to layering: this is where the joint’s durability is determined

Once the design has been finalized, the materials are selected : glass fiber, silica, PTFE, metal mesh/foil, and anti-corrosion barriers each address a specific need.

• Glass fiber provides structural strength and resistance to high temperatures.
• Silica is used where temperatures exceed the heat resistance threshold of glass.
• PTFE provides chemical resistance.
• Metal foils/meshes act as a thermal barrier and/or protection against corrosive agents, depending on their position in the sequence

Next comes layering, the most delicate phase of the entire process. The materials are precisely cut and layered in the sequence established during the design phase. Machine precision is necessary here, but not sufficient: recognizing localized stress between layers with different coefficients of expansion—before it becomes a problem under thermal load—requires direct, field-proven experience. It is that subtle difference that only becomes apparent once the expansion joint is put into service.

From the workbench to the plant

Once the layering is complete, the process moves on to sewing and assembly. The expansion joints are reinforced, the flanges are prepared and positioned according to the design. Before delivery, each expansion joint is inspected for dimensions, alignment, and finish quality. A component that is out of specification can compromise the seal in the plant or complicate installation in a way that is difficult to correct once in place.

The product that leaves our production line is a component built to withstand real-world operating conditions, designed to perform reliably even where temperatures are high or the environment is chemically aggressive.

At New Componit, we have been manufacturing textile expansion  joints since 1986. Over forty years of production, we’ve accumulated hands-on experience that no manual can provide: how expansion joints behave under prolonged thermal stress, where they fail prematurely, and why. That knowledge goes into every component we produce, even before we cut the first layer.

If you have a specific application to evaluate or want to understand which configuration is best suited for your system, we’re available for a direct consultation.

Have you ever come across a fabric expansion  joint that has deteriorated earlier than expected, for no apparent reason? In most cases, the answer does not lie in the quality of the expansion joint itself. It lies in what has been placed on top of it.

When a component designed to move and dissipate heat is treated as a fixed pipe, wear and tear accelerates and the problem only becomes apparent months later, during maintenance, by which time the damage has already been done. Understanding why this happens is the first step towards preventing it from happening again.

A fabric expansion joint is not a pipe: treating it as such has a cost

A pipe is static. You cover it, insulate it, fit a metal sheet over it and leave it alone for years. A fabric expansion  joint works in a completely different way: it absorbs the thermal expansion of the duct and dampens vibrations, which means it has to move with every thermal cycle and every change in pressure.

If you encase it in a rigid cover, you are working against its natural function. The fabric continues to move – it cannot do otherwise – but it does so against a constraint that was not intended. Over time, that constraint becomes the main cause of premature deterioration. It is not a question of the quality of the material, but of how it was installed.

When heat cannot escape, it builds up where it shouldn’t

There is a second effect, less visible but just as significant. The fabric expansion joint is designed to release heat to the outside, so when you cover it with a tightly-fitting metal sheet, that heat becomes trapped between the fabric and the covering.

In technical terms, this is known as ‘heat trapping’. Internal temperatures rise above design specifications, the fabric operates under more severe conditions than anticipated and its service life is consequently reduced. From the outside, nothing appears amiss. But the process is already underway, silently, with every cycle.

Two solutions that protect without stopping the movement

If you want to reduce heat loss along the duct without damaging the expansion joints, there are two approaches that that can solve the problem at its root

• The bolster bag is a flexible insulating product that is installed beneath the expansion joint, between the fabric and the supporting structure. It protects against radiant heat without restricting movement. It is removable, making it ideal for those who need to inspect the joint during routine maintenance without having to perform any additional operation.
• A spaced exterior cover is the right choice when protection from impacts or the elements is needed. In this case, the cover is kept raised above the expansion joint, with a ventilation gap that allows heat to dissipate normally. That spacing is not a compromise, but an integral part of proper operation.

Two different solutions for different needs. Both are based on the same principle: the expansion joint must be able to do its job.

Proper insulation means knowing what you’re insulating

Every component of a system has its own requirements and an effective insulation plan starts with this distinction. Fabric expansion joints aren’t a difficult-to-manage exception; they’re simply elements that require a different approach than the standard one. Recognizing this early on means avoiding premature replacements and unplanned downtime that could have been prevented by making a different choice during installation.

If you’re evaluating how to manage textile expansion joints in your system, or if you’ve already noticed signs of wear that you can’t explain, New Componit’s technical team is available for a direct consultation. Let’s analyze the situation together and we’ll recommend the solution best suited to the actual conditions of your system.

Contact us anytime:

There is always a challenge behind every innovation.

For New Componit, that challenge began years ago: to imagine a fabric expansion joint capable of functioning even in the presence of insulation, without losing its mechanical properties and at the same time guaranteeing durability and safety.

An idea that is as simple as it is complex to implement, which has led to the development of a new generation of high-performance textile solutions: Airflex expansion joints.

When insulation becomes a strength

A fabric expansion  joint is not just a simple component. It is a key element within a plant, because it must absorb vibrations, compensate for movements and withstand often extreme temperature and pressure conditions.

With Airflex, New Componit has opened a new phase in the evolution of industrial fabric expansion joints.

The main innovation concerns the possibility of insulating the expansion joint externally, allowing it to operate at temperatures up to 800°C without compromising its efficiency. This is an important technical achievement, because traditionally insulation tended to reduce the joint’s ability to perform its function. With Airflex, however, insulation becomes an ally, not an obstacle.

But Airflex is not just synonymous with high temperatures.

The line also includes fabric expansion joints dedicated to ventilation, designed to work up to 150°C, with advanced acoustic characteristics that reduce sound vibrations and improve workplace comfort.

What makes Airflex a strategic choice

Airflex fabric expansion joints are not only designed to withstand stress: they are manufactured to offer performance and durability never before seen in other compensators.

Their main features include:

• Structural flexibility, making them ideal for absorbing vibrations and movements without mechanical stress.
• External insulation option, a key element in reducing heat loss and optimizing the energy efficiency of systems.
• Resistance to extreme temperatures, up to 800°C in models designed for high temperatures.
• Customized solutions, thanks to a tailor-made design process that starts with a study of the customer’s needs.

Not just expansion joints: a complete service

New Componit’s real strength lies not only in its products, but also in the integrated service system that accompanies every supply.

Today’s large industrial plants require partners who are capable not only of producing components, but also of following the entire product life cycle: from engineering to assembly, from maintenance to repair.

For this reason New Componit has created a team of specialists, ready to intervene anywhere in the world, offering a complete package that includes:

• Supervision and assistance with assembly,
• Rapid repair interventions to reduce costly plant downtime,
• Preventive maintenance services,
• Thermographic reports for monitoring operating conditions,
• Complementary carpentry and welding activities.

In addition  the Expansion Control System service takes customization to the next level, with:

• Ad hoc design, thermal analysis and test chamber simulations;
• 3D or 2D engineering for total project control;
• Production with premium materials and advanced technologies.

Airflex protects your plant from unexpected downtime

One of the highest costs for an industrial plant is not the price of the component, but the downtime caused by a failure.

Airflex fabric expansion joints, combined with New Componit’s maintenance and repair service, drastically reduce these risks, ensuring production continuity and real savings.

In an increasingly fast-paced and competitive industrial world, relying on standard solutions is no longer enough.

Airflex was created for those who want to guarantee maximum efficiency of their plants, reduce heat loss and have a technical partner always at their side.

Would you like to know how Airflex can improve the efficiency and safety of your plant?

Contact us for a free technical consultation.

‘Tell me the operating conditions of your system and I will tell you which expansion joint to
choose’.

Let’s pick up where we left off: in our last blog post we started with a brief overview of the
factors that influence the characteristics of expansion joints.

With this short guide, we want to help our readers to find their way in choosing the most
suitable expansion joint; in fact, only the product that takes into account a whole series of
factors can perform at its best.

In the previous post we considered high temperatures, pressure and chemical resistance; in
this second part we look at the other conditions that can frequently be found in systems.

1. High need for versatility and compensation of large movements

Every mechanical application requires a certain type of movement and depending on the
nature of the movements required, it is necessary to choose an expansion joint that offers
the right combination of flexibility and precision.

At New Componit, in addition to the already mentioned Piperflex fabric expansion joints,
which are ideal for high temperature wall applications, we offer Enerflex compensators.

The fabric expansion joints of Enerflex line are particularly suitable in energy field, especially
for applications in air ducts and low-aggressive flue gas ducts.

Their multilayer composition and the materials used in their construction guarantee a high capacity to
compensate for very large movements, giving these expansion joints maximum operational
versatility.

2. Need for thermal reduction

In many industrial applications, overheating of components can cause failure or reduce
operating efficiency. Expansion joints with thermal abatement capabilities are designed to
dissipate the heat generated during operation, thus protecting sensitive components and
prolonging system life.

If you are looking for an expansion joint that provides maximum thermal but also acoustic
abatement, we at New Componit can recommend a fabric expansion joint from the Airflex
line.

The Airflex line includes fabric expansion joints that offer high thermal-acoustic
abatement and are insulated for low and high temperatures. In particular, two main groups
can be distinguished within this range: components designed to work fully insulated
externally, applicable at temperatures close to 800°C, and expansion joints designed for
ventilation, capable of working at temperatures not exceeding 150°C, but with significant
noise abatement characteristics

3. Need for noise abatement and vibration damping

If you work in an environment where noise reduction is a priority, such as in an industrial
plant close to residential areas, or you are looking for an expansion joint for applications that
require low noise impact, the expansion joints with noise reduction properties are the
right solution for you.

These expansion joints are designed to absorb vibrations and reduce the noise
generated during plant operation and your choice can be between textile or rubber
expansion joints.

If you are looking for an expansion joint that provides maximum vibration damping, the
fabric expansion joints of Vibraflex line may be the right choice for you. Please note,
however, that the application conditions for this type of expansion joint are low
temperatures (up to 200°C).

Expansion joints of Vibraflex line have different construction solutions, depending on the
design data and characteristics of the conveyed fluids; in particular, if you need your
expansion joint not only to have the ability to dampen vibrations, preventing them from
propagating along the ducts and structure of your plant, but also to have a high noise
insulation performance, we at New Componit have developed the Vibraflex SOUND series
of compensators, which combine vibration dampening and soundproofing.

Rubber expansion joints, on the other hand, are made of any reinforced elastomer
and/or fluorelastomer, such as natural or synthetic rubbers, giving the joints a special
elasticity. Thanks to this characteristic, rubber expansion joints are able to maximise
vibration damping and noise reduction; furthermore, being reinforced and of suitable
thicknesses they also offer good pressure resistance.

Rubber expansion joints are typically used for gas turbine ducts and any fan model, as well
as in hydraulic systems and piping.

If you need maximum noise dampening performance, rubber expansion joints from the
Acuflex range are perfect for you: they provide both high vibration dampening and noise
abatement performance, as well as maximum pressure sealing.

Another solution that combines noise damping and minimum vibration propagation,
indispensable capabilities of expansion joints on military vessels, for example, is the
Navyflex fabric expansion joints: these expansion joints are specifically designed for
naval applications, have a multi-layer design and are capable of excellent pressure
sealing.

After this quick overview it is, therefore, clear that choosing the right expansion joint for
you, requires careful evaluation of your specific operating conditions and project
requirements.

We at New Componit are at your side to offer you the best solutions to meet any challenge,
ensuring that the expansion joint you choose meets your specific operational needs.

Want to improve comfort and performance in your plant with a tailored solution?

“There is always the right expansion joint, even for the most extreme conditions.”

We at New Componit have been repeating this expression for quite some time, and in the light of our nearly 30 years of experience, we can state with conviction that there are expansion joints capable of withstanding any condition but, beware, they must be designed with certain caution.

In fact, in order to perform at its best, the expansion joint must be designed and manufactured according to the required operating conditions, which determine its technical characteristics.

To identify the most suitable fabric expansion joint for your application, you need to take into account:

• temperature;
• pressure;
• chemical composition of the fluid;
• movements;
• need for thermal abatement;
• need for sound abatement.

When we have this information , it becomes easier for us to design the perfect expansion joint for you.

In light of this premise, we thought we would create a short and simple guide that can help you identify the component best suited to your needs.

1. High temperatures environments

In high-temperature environments, the expansion joints have to maintain their mechanical and structural properties even when heat conditions become extreme, without suffering deformation or loss of performance.

If you operate in high-temperature conditions, you should opt for multilayer textile expansion joints or metal joints; of course, the specific choice also depends on the other requirements of your plant and the system to which the joint will be applied.

For example: we at New Componit ( specialized in customized textile solutions for heat and temperature change problems) make several lines of textile expansion joints suitable for flue duct systems that work at high temperatures and each of these lines is designed for a specific application.

In particular, if you need an expansion joint for very high temperature flue ducts, operating in chemically aggressive environments, you can choose joints from the Petroflex line. These textile expansion joints offer maximum resistance to extreme temperatures, reaching up to 1300°C.

With the same chemical resistance needs, but applying the expansion joint to flue gas exhaust ducts, the most suitable textile expansion joint is instead part of the Powerflex line.

If, on the other hand, you need expansion joints that withstand high temperatures to be applied to the walls of industrial boilers, the Piperflex line is the right solution: these products offer maximum compensation of movements ( axial and lateral) at the same time, even at temperatures of 850°C, making them ideal for wall, roof and bottom penetrations of industrial boilers.

As an alternative to multilayer textile expansion joints, if you operate at high temperatures, you can choose a metal expansion joint: these compensators are made of metal, such as : steel or special alloys; this makes them particularly robust, withstanding high loads, high temperatures and significant pressures.

2. Resistance to pressure and mechanical stress

We have already seen that metal expansion joints are very strong and therefore particularly suitable for operating under high pressure conditions; but there are also textile expansion joints designed to be particularly resistant to mechanical stress.

Textile expansion joints that must withstand pressure are of the multilayer type; in fact, the multilayer design allows different materials to be combined in order to improve the performance of the expansion joint.

In particular, we at New Componit have designed textile expansion joints that are mechanically strong while having strong chemical resistance, thanks to the use of “laminated” fabrics that combine the characteristics of technical fabrics based on glass fiber and fluoropolymers with PTFE cast films.

In fact, joints from the Turboflex line are the best solution for you, if you need a compensator that is particularly resistant to pulsation and erosive phenomena related to turbulence and high smoke velocity.

3. Aggressive environments requiring special chemical resistance

In chemically aggressive environments, corrosion resistance becomes a fundamental necessity: the presence of corrosive chemicals can rapidly deteriorate expansion joints made of inadequate materials, leading to premature failure.

For applications in such environments, it is important to choose expansion joints made of materials that can ensure that the chemical, physical and mechanical properties of the compensators themselves will remain intact over time.

At New Componit, we have designed a line of textile expansion compensators suitable for applications in desulfurization or denitrification plants, where significant concentrations of acid condensates or dust accumulations occur.

In fact, for the construction of the textile expansion joints in the Chemflex line, we carefully selected materials that protect the compensators from the chemical attack of corrosive compounds, ensuring a long service life.

Chemflex joints are generally single-layer and made on a glass fabric or wire cloth and coated with PTFE; this type of composition ensures maximum chemical resistance, but also excellent pressure resistance.

Alternatively, Acuflex elastomer expansion joints are the perfect solution, even better performing in particularly aggressive environments: Viton is a favorite compound, but we also handle neoprene and EPDM.

As you may have already realized, taking into consideration only three factors (temperature, pressure and chemical resistance) the possibilities are many and that is why we always insist with our customers on the importance of product customization: in fact, it is the operating conditions and the performance required of the product that determine its characteristics.

Don’t miss the second part of this guide, where we will discuss the most suitable expansion joints if you need thermal, acoustic or large movement compensation.

At New Componit, we are specializes in textile solutions that can solve problems related to heat, temperature change, noise and fire. For more than 35 years we have been taking our engineering expertise all over the world, measuring ourselves against all kinds of critical issues in plants that develop extreme temperatures and finding ever more innovative solutions.

Want to improve comfort and performance in your plant with a tailored solution?