A guide to silicone gaskets

Explore everything you need to know about silicone gaskets, their advantages and applications across a range of industries.

Silicone gaskets have become an essential implement for myriad industries and countless manufacturing processes. Before you can understand why these small components are so relied upon, it is important to understand what they are, what they are made from, and their many advantages. From spaceships to iced buns, silicone gaskets are an essential ingredient in industrial processes. Let’s explore why.

Explore everything you need to know about silicone gaskets, their advantages and applications across a range of industries.

What is a silicone gasket?

A silicone gasket is a type of mechanical seal that can be used to cap the junction between two surfaces. Silicone gaskets are utilised in a wide range of industries including aerospace, electrical and renewable energy. Among other things, silicone gaskets are valued for their safe usage, as they were developed as a modern alternative to asbestos gaskets which were commonly used before the dangers of asbestos were discovered.

What is silicone?

Silicone is a type of synthetic rubber. It is a polymer consisting of multiple units of siloxane, which is a compound formed by joint silicon and oxygen atoms.

Although at one point it was used for the production of silly putty, scientists soon uncovered the potential of silicone for a plethora of not-so-silly applications. The soles of the very shoes that Neil Armstrong wore to take the first steps on the moon were made from silicone rubber. One of the most common applications of silicone today is for making silicone gaskets, but it is also used in cosmetics, cookware, construction, and more.

How is silicone made?

There are two methods used for synthesising silicone:

As silicone is a man-made substance, there are a few steps involved in both processes. To keep things simple, we will just focus on the most commonly used method, the Direct Process.

How the Direct Process works

  1. Firstly, naturally occurring silicon metal is placed in a hot furnace wherein copper is present.
  2. The furnace is heated to between 300-400°
  3. Methyl chloride, which is an organic compound, is added to the furnace.
  4. Methyl chloride reacts with the silicon metal and forms an organosilicon compound called dimethyldichlorosilane, otherwise known as DDS.
  5. The DDS is purified and combined with water in a reactor.
  6. The result of this combination is the formation of polydimethylsiloxane (a type of silicone polymer) and hydrochloric acid.
  7. The silicone polymer is separated from the acid and is then neutralised.
  8. The neutralised silicone polymer is then filtered and dried out, and the end product of silicone is formed.

How to make a silicone gasket

Now that we know how silicone is made, let’s investigate how silicone gaskets are made. Silicone gaskets are made in numerous ways, including by 3D printing or on a roll for kiss-cut gaskets.

For a large-scale production of silicone rubber gaskets, gaskets are made in factories. Large flat pieces of silicone rubber are split to width with a bun-splitting machine, depending on the desired thickness. The silicone gaskets we provide, for example, range between 0.3mm thick and 20mm thick, to be utilised for a wide array of applications.

Once at the desired thickness, the silicone rubber is usually laminated using a laminating machine, which attaches a paper cover that is only pulled back upon application of the gasket. The shape of the gasket is formed when the laminated material is stamped and cut by a machine. Once the gasket is the desired shape and thickness, it can be prepared for distribution.

The advantages and disadvantages of silicone gaskets

There are many advantages to choosing silicone gaskets over other types of gaskets, as silicone has properties that make it useful in a range of environments.

The advantages of silicone gaskets

Firstly, silicone is extremely heat resistant. Our silicone gaskets can tolerate temperatures of up to 230°C without changing shape or losing their function. Silicone is equally resistant to the cold and can withstand temperatures as low as -60°C.

Silicon gaskets also have excellent external sealing properties, meaning that they effectively block out air, dust, and water. This feature helps to prolong the lifespan of the products and the surfaces upon which they are applied.

As we’ve mentioned, silicone gaskets were partly developed as a replacement for asbestos gaskets. This is because of silicone’s low toxicity – not just compared to asbestos, but also in general. Therefore, it makes it safer to manufacture and use. Some of our gaskets also benefit from being specially designed for flame resistance, or to meet FDA and WRAS guidelines.

Another benefit of our silicone gaskets is that they are a great NVH solution. They help reduce noise, vibration and harshness in vehicles and machinery. The multifaceted benefits of silicone gaskets make them applicable to a range of surfaces across an array of industries. However, there are rare instances in which silicone gaskets may not be the best choice of gasket.

The disadvantages of silicone gaskets

The primary disadvantage of silicone gaskets is their higher price point compared to other kinds of rubber gaskets. Although they may be pricier initially, they are likely to diminish costs further down the line thanks to their longevity and improved uptime.

The other disadvantage of regular silicone gaskets is their low tear strength. This means that silicone gaskets may not be as strong as other rubber gaskets when pulled in multiple directions. However, there is a solution for this. High tensile strength silicone is modified specifically to increase tear strength.

Although these two arguments are valid, in general, silicone gaskets are a superior type of gasket.

Different applications of silicone gaskets

Thanks to their versatility, silicone gaskets can be used for a variety of purposes across many different industries. For example:

  • The automotive sphere – They can be applied to interior cabins and roof rails.
  • Aviation and aerospace – Silicone gaskets are utilised in these sectors largely due to their high-temperature resistance. For instance, gaskets are used to seal aircraft and spacecraft components.
  • Medical systems – FDA-compliant silicone gaskets are commonly used on medical equipment and machinery.
  • Renewable energy – Not only does the use of silicone gaskets contribute towards reducing greenhouse gas emissions, but the gaskets themselves are often used to seal green energy-generating machines, such as solar panels.
  • Food processing – FDA-approved silicone gaskets are used throughout the food industry, thanks to their high-temperature resistance and low toxicity. They are applied to food-related machinery, such as cake mixers.

Final Thoughts

Thanks to silicone’s unique and versatile properties, silicone gaskets provide seamless and reliable performance for manufacturers of all kinds. To further their utility, we provide our silicone rubber gaskets in a range of shapes, sizes and quantities to suit your specific needs.

From double-sided adhesive gaskets to perforated gaskets, we create bespoke silicone gaskets to ensure maximum ease of assembly and reliability. We even offer silicone gasket assembly for those who need it. To find out more about the benefits of silicone gaskets, or to order your sample of our high-quality silicone gaskets, reach out to Ramsay Rubber today.


Get in touch

Please feel free to get in touch, to speak with one of our team of experts or simply fill out our online contact form below. We look forward to hearing from you.

  • Max. file size: 8 MB.
  • Please enter a number from 2 to 2.
  • This field is for validation purposes and should be left unchanged.
Scroll To Next Section

Get In Touch
Ramsay Rubber & Plastics Limited
Vulcan Road, Bilston
West Midlands WV14 7HT
T +44 (0) 1902 407150
F +44 (0) 1902 407160