The modern technological world is filled with ‘extrusions’. They are all around us, in the form of small and not-so-small cross sections. The function of an extrusion is to form seals between components of complex machinery and keep them functional. And, depending on the ‘type’ used, they can make a big difference to how a machine operates.
Some of the most desirable types of extrusion — and especially for use in HVAC systems — are those made from silicone. Silicone, which is a type of rubber, has a robust set of properties. For one, silicone can withstand extreme temperatures, both high and low.
Ranging from -60°C to temperatures exceeding 200°C. (And there are even higher grades that can be manufactured to withstand temperatures well above 200°C.) Ideal for HVAC units that work round the clock to keep large numbers of people in large buildings comfortable in summer and winter conditions.
In addition to this, silicone is also one of the more resistant properties to the constant vibrations of working machinery. It can be difficult to locate the source of the problem if a tiny extrusion has dislodged. Vibration-resistant properties make silicone extrusions less likely to disengage or fall out of place, therefore minimizing the need for costly repairs. Finally, silicone is also more durable than most other materials when it comes to exterior or semi-exterior environments, such as that of rain or ultraviolet light.
Protecting electrical components
Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections
As a result of this favorability, there is already a considerable number of different types of silicone extrusions that can be found in a lot of HVAC systems. These include HVAC sealing gaskets, hatch seals and vibration isolation pads. But also silicone sponges, which act as a protective layer of thermal insulation. As well as providing thermal insulation, silicone sponges can double-up as a form of acoustic insulation, with considerable noise reduction and anti-squeal properties.
Silicone enclosure gaskets protect electrical components, and environmental seals — as the name suggests — help to keep everything protected from the sometimes harsh elements of the environment outside. Silicone is useful in HVAC systems because it offers enhanced sealing and compression protections over most other materials.
Closed cell structure
On a material level, silicone has a ‘closed cell structure’, which helps to keep out moisture ingress, along with water and dust. The combination of a closed cell structure, along with sealing and compression benefits, makes silicone ideal for exterior seals and gaskets in and around HVAC systems.
The softer grades of Silicone have an excellent memory and low stress relaxation, which in turn helps to prevent common faults with HVAC systems — usually caused by gasket failures made from other materials that soften and compress inaccurately. The low stress relaxation properties require minimal force on behalf of the engineers sealing the enclosures, while the memory-properties of the silicone allow it to conform to awkward shapes and gaps of various widths. Manufacturing HVAC systems proactively with silicone in mind can allow more design flexibility on behalf of the engineers.
Inevitable rapid movements
General purpose solid silicone or silicone sponge is suitable for many HVAC applications
And, as mentioned above, vibration isolation pads work as dampers to protect against the inevitable rapid movements of the systems as they power along. But also to help withstand the vibrations of HVAC units on transport systems, such as buses and trains, which naturally vibrate as they run over imperfections on rail and road tracks.
As it happens, general purpose solid silicone or silicone sponge is suitable for many HVAC applications, not just those discussed above. The designs of the extrusions would be different, reflective of their function, but the material would be the same. In some instances, customers may also require a flame retardant silicone — certified to UL94 specifications — in order to meet safety standards in certain situations or environments.
Great temperature ranges
For all its material advantages, silicone is generally more expensive than the other types of material rubber that are used to manufacture extrusions, such as ethylene propylene diene monomer (EPDM). And while other materials do of course have stand-out benefits of their own — EPDM for example is more hard-wearing than silicone — silicone is still often the extrusion ‘type’ of choice because of its ability to withstand great temperature ranges.
This is very important for heating and air conditioning systems. Because some of the most common factors that cause HVAC systems to break down are as a result of seal and gasket failure, which can come about as a result of an overheating unit.
Very cold environment
Chances of a unit overheating can be just as likely — in fact perhaps more so — where the system has to operate in a very cold environment.
With the threat of climate change etched more than ever into the public discussion, we can predict that there will be a steady increase in the amount that this material is used to make up the HVAC seals. And not just because, as temperatures continue to increase and summers get hotter and more prolonged, there will be an increased demand for them.
Effective public relations
It is no secret that HVAC systems can be relatively expensive to run
It will become a matter of effective public relations for managers, building regulators and transport officers to make sure that the equipment they are using — and making — is ‘green’. By using the right materials that help conserve energy and increase efficiency, this will not only sit right with the general public, it should also be more economical, too.
It is no secret that HVAC systems can be relatively expensive to run. Minimizing wastage, and the time spent on call outs and repairs will make a notable difference. Of course there are many other ways to also set about making air conditioning and heating units more efficient.
Using seals or gaskets made from silicone is just one small piece of the puzzle. But utilizing them will almost certainly be more beneficial than you might imagine. And anything that is a step in the right direction is a welcome change.