The gasket industry generates about $8 billion in annual revenue in the United States.
Silicone gaskets offer a wide range of benefits, making them a top choice for gasket manufacturing. As a flexible material converter, we’ve worked with a variety of gaskets, which is why we’re answering questions about one of the most common gasketing materials.
To learn more about the uses and benefits of silicone gaskets, read on for a guide intended to help you discover a suitable gasketing material.
Types of Gaskets
The type of material in your gasket depends on its intended use. For example, if you’re dealing with a rigid object, you need a gasket that fits the set shape. Doors and moving structures need something more flexible.
Before you design a gasket, consider your needs, including temperature, pressure, corrosion resistance, availability, and cost.
Gaskets must be solid so they don’t allow materials to pass through. Some also need to deal with energy discharge. You can have many different types of gaskets, including:
- Pipe gaskets
- Gasketing tape or adhesive
- Gasketing foam
And many different materials, including silicone, neoprene, EPDM, Teflon, Gore-Tex, and graphite gaskets.
What is a Silicone Gasket?
When you’re looking for multi-temperature range, high-performance mechanical seals with high resilience and durability, you should consider silicone gaskets.
Silicone gaskets can withstand high and low temperatures, making them a versatile material. Use silicone gaskets when you need a material with high-temperature resistance, a low compression set, and good electrical insulation.
What Are the Uses of Silicone Gaskets?
Because of their versatility, silicone gaskets have uses in many different industries.
AEROSPACE
Silicone gaskets resist extreme temperatures, UV light, ozone, and chemicals. Because they can handle extreme weather and temperatures without wearing down, they’re often the right fit for airplanes, space shuttles, and similar vehicles.
TRANSPORTATION
Silicone gaskets are stable and durable, maintaining their resilience and strength even in extreme conditions. Because they can handle unnecessary stress without issues, they are great for personal, commercial, or industrial vehicles. In addition, they reduce vibrations, provide high-quality radiator seals, and are otherwise used for mass transit systems like buses and trains.
COMMERCIAL APPLICATIONS
In the construction industry, silicone gaskets are used as seals for HVAC systems and windows or doors. They can also be used in engine gaskets to vent ducts.
Other silicone gasket uses include serving as seals in food processing machinery and industrial oven seals in the food industry. The medical industry uses them for medical equipment like healthcare devices or for pharmaceutical purposes.
What Are the Benefits of Silicone Gaskets?
Before we get into the different types of silicone gaskets, it’s worth considering the properties that differentiate them from other gasketing materials.
There are thousands of materials to make gaskets with, but silicone gaskets stand out thanks to the benefits that allow them to be used in indoor and outdoor applications.
BENEFIT #1: ABILITY TO WITHSTAND HIGH AND LOW TEMPERATURES
Silicone gaskets can withstand temperatures up to 392 degrees Fahrenheit continuously. This makes it great for many industrial applications. It can be exposed to high heat levels without degrading or wearing out. Silicone gaskets can also withstand heat up to 428 degrees Fahrenheit intermittently.
On the other hand, they can also withstand extremely cold temperatures. They can remain flexible at as low as -94 degrees Fahrenheit.
BENEFIT #2: EXCELLENT INSULATION
Silicone gaskets have conductive capabilities that make them excellent insulators of electricity. By blending silicone with nickel-graphite or silver-plated aluminum particles, silicone gaskets can shield electromagnetic interference (EMI).
Silicones are found in most high-voltage insulators and other electrical components. They can be cross-linked by different chemical reactions, making them non-reactive at high temperatures. The electrical industry relies significantly on these non-reactive materials.
Where electromagnetic discharge is a problem, silicone can also be blended with a semi-conductive carbon to prevent electromagnetic discharge.
BENEFIT #3: HIGHLY DURABLE
Silicone gaskets are highly durable and resistant to UV light, ozone, and extreme weather conditions, making them ideal for outdoor gasketing.
Plus, the durability of silicone makes the gaskets highly economical since it is a reliable and stable material. You can use silicone gaskets for a long time without them showing wear, and they don’t require much maintenance once installed.
BENEFIT #4: FDA APPROVED
Because silicone gaskets are FDA-approved, they can be used in medical equipment, health care instruments, and food processing plants. They can also be mixed with other FDA-approved materials for high tear strength.
Unlike asbestos gaskets, silicone gaskets are also physiologically inert (not toxic or harmful to people). Their high tear strength and inertness make silicone gaskets useful for healthcare, food processing, medical diagnostic equipment, and pharmaceuticals.
BENEFIT #5: COMPRESSION SET RELIANCE
Compression set reliance means that silicone gaskets function well under pressure by returning to their original thickness even after being compressed for long periods.
Silicone gaskets are a smart choice for a lower compression set. A compression of 100% means the material will never return to its original thickness. Lower compression set reliance materials ensure the material doesn’t get deformed in certain temperatures.
Matching the compression set reliance of your material to your intended use is essential. If the gasket material deforms, the seal will fail, leading to leaks and contaminations.
BENEFIT #5: FLAME RETARDANT
Silicone gaskets have low flammability levels, which makes them ideal for industries that generate excessive heat. They can be used in telecommunications equipment and mass transit systems.
Silicone gaskets meet the testing requirements from Underwriters Laboratories (UL) for fire safety and flame resistance, meaning they can achieve UL94V0, UL94V1, and UL94HF1 flammability standards.
BENEFIT #6: WATER-REPELLING MATERIAL
Silicon gaskets have a water-repelling material that repels liquids, resists moisture, and maintains a watertight seal. This sealing ability is essential for industries dealing with moisture or water and great for outdoor use in wet weather conditions.
What Are the Types of Silicone Gaskets?
Silicone gaskets can come in sheets or rolls in different thicknesses. However, you can also have solid, sponge, or foam silicones depending on your needs.
TYPE #1: SOLID SILICONE GASKETS
Solid silicone gaskets are not always soft but rather tightly packed and more rigid than sponge silicone. If you need a seal rating of IP67 or higher, you’ll want to choose solid silicones.
Solid silicones can offer exceptional sealing capabilities, but remember that they’re challenging to compress because of their hardness and require 15 to 20% compression.
TYPE #2: SPONGE SILICONE GASKETS
Sponge silicone gaskets offer more cushioning and padding. They can be open-cell or closed-cell. Open-cell silicones contain pockets that allow water, air, and chemicals to pass unless the gasket is compressed.
Closed-cell silicones have pockets filled with nitrogen to prevent water, air, or other chemicals from passing through, even at low compression. They will need at least 50% compression. Sponge silicone gaskets have a higher temperature threshold of 500 degrees Fahrenheit.
TYPE #3: FOAM SILICONE GASKETS
Foam silicone gaskets can be soft, medium, firm, or extra-firm, offering different compression levels.
Like sponge silicone gaskets, foam silicone gaskets also need at least 50% compression. They can be open-cell, closed-cell, or a mixture of both. They have a temperature threshold of 400 degrees Fahrenheit.
TYPE #4: DIE CUT SILICONE GASKETS
Die cut silicone gaskets are the typical type of gasket. It’s a more economical option, especially for large volumes, because you can produce thousands of die-cut silicone gaskets per hour.
Die cutting uses a specialty tool to create custom parts. If you’re using your design with custom sizes and thicknesses, die cut silicone gaskets could be a good option for you.
TYPE #5: MOLDED SILICONE GASKETS
Molded silicone gaskets provide a higher performance seal than die-cut silicone gaskets. However, this might come at a higher upfront cost even though both are good for high-volume production.
TYPE #6: CONDUCTIVE SILICONE GASKETS
Conductive silicone gaskets are made up of a mix of high-quality silicone and conductive particles. They are filled with conductive materials like nickel, carbon, and silver-plated nickel, and are used for electronic equipment.
TYPE #7: FDA (FOOD GRADE) SILICONE GASKETS
FDA-approved silicone gaskets are generally used in the food processing industry. They are odorless, tasteless, and fungus-resistant. They also can handle extreme cold and heat, making them ideal for places with food around, like dough or cake mixers.
TYPE #8: FLUOROSILICONE GASKETS
Fluorosilicone, or fluorinated silicone rubber, is similar to silicone. Silicone is not ideal for oil or petroleum-based chemicals, which is where fluorosilicone comes into play.
Materials like fluorosilicone can withstand extreme temperatures and resist fuels, oils, and other petroleum-based chemicals.
How Do Silicone Gaskets Compare to Rubber Gaskets?
While rubber for rubber gaskets comes from a rubber tree, silicone is synthetic.
Silicone gaskets can be more efficient and perform better than rubber gaskets. For instance, silicone gaskets are better when dealing with extremely high temperatures.
Natural rubber can work well in temperatures from -58 degrees to 176 degrees Fahrenheit intermittently. Silicone can handle more extreme temperatures, from -94 degrees to 426 degrees intermittently. Natural rubber starts to wear down at 176 degrees and melts by 248 degrees.
Rubber is not used with ozone, strong acids, fats, oils, and grease. Silicone, on the other hand, can be used with these materials. For outdoor applications, you can use silicone gaskets in UV and extreme weather conditions.
Solving Your Gasket Needs
Now that you know the benefits of silicone gaskets, you’re ready to choose a gasket adhesive that suits your needs.
Yet, crafting gaskets takes more than just finding the right material. It’s one thing to build the perfect gasket once, but how can you consistently manufacture your part to reduce the chances of product failure?
If you’re interested in learning more about gasket manufacturability, you can reach out to us to schedule a flexible materials consultation and any questions you might have about gasket manufacturing.
We’re here to help you through your product development process. For additional information and resources, please visit our Learning Center.
Originally published: February 24, 2022
