Silicone O Rings
Silicone o rings, or VMQ o rings are molded products wedged between mechanical parts to seal and prevent fluid or gas leakage. They are available in many standard inch and metric sizes.
VMQ o-rings display high performance in static, high temperature environments. They have outstanding flex and fatigue life, strong ozone and UV radiation resistance as well as physiologically neutral and insulating properties.
Extreme Temperature Resistance
O-rings must withstand a lot of pressure and environmental conditions to keep their integrity. They must resist high and low temperatures, abrasion, vibration, chemicals and corrosion. To do this, they must be made of a strong and durable material that is capable of withstanding these conditions without losing their useful properties or becoming damaged. For these reasons, o rings are typically manufactured with a range of fluoropolymer materials like PTFE, PEEK, PVDF and PCTFE.
PTFE is a very durable material that is capable of withstanding extreme temperatures and harsh chemical environments. It is a very good choice for o-rings used in oil and gas, aerospace, automotive and medical industries Silicone o rings as it does not burn or degrade at high temperatures. It is also resistant to acids and organic solvents that can degrade other o-ring materials.
Silicone o rings are very versatile and work well in a variety of temperatures, including -40°C to 400°C. They are odorless, non-toxic and will not grow mold. They have high flexibility, fatigue life and tear resistance but low tensile strength and abrasion resistance. They can be used with a wide variety of fluids and are resistant to animal and vegetable oils, greases, ozone, oxidative environments and most lubricants.
VMQ, often abbreviated as silicone rubber, is a synthetic rubber. It is made from a mixture of silicone molecules and organic compounds. It is resistant to high and low temperatures, abrasion, corrosion, ozone, water and steam. It is also very effective in static applications.
Chemical Resistance
Silicone o rings have excellent resistance to chemical exposure including oily, fuel and mineral oils as well as acids and alkalis. They also offer good ozone resistance and weathering characteristics. This enables them to be used in environments which are subject to harsh chemicals, including some corrosives. The material can also be formulated to be electrically resistant or conductive. This versatility makes silicone a great choice for sealing applications which are exposed to harsh environmental conditions.
Food processing facilities need to ensure that all their equipment is clean and safe for consumption. Silicone is a popular material for this purpose due to its FDA-approved and medical compliant properties. It is able to resist both extreme hot and cold temperatures while still maintaining its flexibility. It can also be molded into more complex shapes and adhere to tight tolerances. In addition, it is available in metal detectable compounds, making it easier for inspectors to identify if the seal has been compromised and therefore potentially contaminated the food.
Although silicone has good high and low temperature performance, it is not recommended for dynamic applications as it does not have good tear and abrasion resistance. For this reason, it is often combined with other more resilient materials for dynamic sealing.
Low Compression Set
Silicones have one of the widest temperature ranges of any o-ring material and are also highly resistant to ozone, UV radiation and many oils. They have low tensile strength and abrasion resistance, however, which makes them limited to static applications.
In order for an o-ring to seal, it must be compressed evenly around its surface. Inconsistent compression will cause an uneven flattening of the cross-section, which reduces the sealability and lifespan of the o-ring.
A low compression set is also important for applications where the o-ring must maintain pressure over time, such as the socket component of a hip prosthetic. This is because the o-ring needs to remain consistently compressed without Silicone O Rings – Supplier a loss of pressure for it to continue functioning effectively.
Selecting the right o-ring for your application requires considering a number of factors such as operating conditions, sealing pressure, size, durometer, chemical compatibility and more. Marco has a variety of standard and custom silicone o-ring sizes available to suit all kinds of applications. We can help you find the best solution by filtering by function, end market and chemistry. Contact us today to get started. You can also browse our selection of high-performance o-rings for more options. Our o-rings are manufactured by the industry’s most trusted brands to ensure you receive a quality product. We offer a lifetime guarantee on all our products.
Aesthetics
O-rings are available in a wide variety of materials, sizes and shapes to meet a range of sealing needs. While nitrile and Viton are common O-ring material choices, silicone is an attractive alternative for its impressive range of performance properties.
Silicone can withstand extreme temperatures without losing its flexibility and elasticity. In addition, it is not as affected by UV rays and ozone as other O-ring materials. This makes it a good choice for outdoor applications like condensers, extraction units and piping systems.
The low modulus of silicone allows it to be molded into intricate, specialized forms and adhere to tight tolerances. This makes it a great choice for applications that require precision and a smooth finish, such as button covers or handle seals.
It is odorless and non-toxic, and it does not grow mold. It is also an excellent electrical insulator.
A silicone O-ring is an elastomer – a polymer that deforms and returns to its original shape when pressure is removed. FFKM (fluorocarbon) and perfluoroelastomer (PFA) are other common O-ring materials, but they are not as capable as a standard silicone O-ring. FFKM o-rings have carbon-fluorine bonds – the strongest bond in organic chemistry – that make them resistant to high temperature and chemical exposure. Moreover, FFKM can withstand pressure and abrasions. TRP Polymer Solutions offers a full line of food-grade, FDA-approved FFKM o-rings to ensure safe and reliable operations in demanding environments.