Silicone hoses are typically reinforced for added strength against boost pressure and long-term stress in automotive applications. Silicone is just a flexible heat-resistant material and on its own it would balloon or burst under relatively low pressure. The reinforcement fabric is the structural backbone that allows it to withstand the pressure. Together they make a very durable and long-lasting hose or coupler. The temperature rating of a silicone hose more so due to the fabric reinforcement type and not the silicone itself.
We will discuss the three main types of fabric reinforcement used in silicone couplers: Polyester, Aramid/Meta-Aramid, and Fiberglass
1) Polyester
This is the most commonly used fabric reinforcement. It is cheap and easy to work with. It provides plenty of strength for most applications and allows the hose to have the most flexibility. It has a maximum working temperature of 350 degrees Fahrenheit. It can also weaken over time when it is exposed to prolong use at high temperatures. This is the cheapest option and works well for a large majority of silicone coupler applications.
2) Aramid/Meta-Aramid
Aramid is extremely strong and is significantly better at handling prolonged exposure to heat. This fabric has a maximum working temperature of 500 degrees Fahrenheit. Because of its strength it can withstand higher boost pressures too. This material is more expensive and therefore adds extra cost to a silicone hose made with it. It is slightly stiffer and therefore the silicone hose will be slightly stiffer too.
3) Fiberglass
Fiberglass has the highest heat resistance of all the materials. Hoses made with this can be made to withstand temperatures around 750 degrees Fahrenheit! Fiberglass is the strongest reinforcement as well as the strongest reinforcement at or near its max temperature. It is uncommon to see hoses reinforced with fiberglass in the automotive world, because it is overkill for any but the most extreme applications. It is the most expensive and most difficult to work with. The lack of flexibility limits the hose shapes that can be made.
The reinforcement fabric is a vital to the overall construction of the hose. However, there are many other factors that can affect the quality and durability of the hose. There are even different qualities and thicknesses of the reinforcement fabrics that can be used within each type that can also affect the quality of the hose.
If you need help determining what is right for your application, feel free to reach out!