What Types of Rubber Are Used for O-Rings?

Did you know that O-rings are one of the most commonly used seals in modern industry? O-rings are circular seals that prevent liquids and gases from escaping a connection made between two surfaces. They come in various sizes, shapes, and materials, with rubber being the most common material.

What are O-Rings?

As the name suggests, O-rings are circular seals made of rubber; they are used to create a watertight connection between two surfaces, preventing liquids and gases from escaping. O-rings come in various sizes and shapes depending on the application they are being used for and can be customised to fit into particular spaces or machines. They are usually placed in grooves on these surfaces, which are then pressed together to create a seal.

Applications of O-Rings?

O-rings are used in a wide variety of applications, with some of the most common being in plumbing, machinery, automation systems and automobiles. These days, they can also be found in aerospace equipment and medical devices. O-rings are an important component of any system that requires a watertight seal between two parts. For example, they are used in fluid power systems and hydraulic machinery to ensure that oil, liquids or gases do not escape.

What Types of Rubber Are Used for O-Rings?

When selecting the right type of rubber for an O-ring, it is important to consider the operating temperature and environment, as well as chemical compatibility. Generally speaking, there are three main types of rubbers used in the manufacture of O-rings: nitrile rubber, silicone and FKM (fluoroelastomer).

Nitrile Rubber (NBR): Nitrile rubber is the most commonly used material for O-rings. It has excellent resistance to oil and gas, as well as to many acids and alkalis. It can also maintain good flexibility over a wide temperature range (-20°C to +110°C).

Silicone Rubber (VMQ): Silicone rubber is commonly used where an O-ring needs to resist high temperatures, up to 200°C. It also offers excellent resistance to ozone and UV light, making it suitable for outdoor applications. However, silicone is not as resistant to oils and petroleum products as nitrile rubber.

FKM (Fluoroelastomer): FKM is often chosen for O-rings due to its excellent resistance to petroleum-based oils and fuels. It is also resistant to acids, chemicals and high temperatures (up to 200°C). FKM also offers good physical properties such as a low compression set and excellent tear strength.

When an O-ring seal supplier is helping you to determine the best material for your application, they will take into account factors such as pressure, temperature, media and environmental conditions. The right material choice is essential for an effective seal and long service life. Choosing the wrong elastomer could significantly reduce the performance of an O-ring seal.

When choosing an O-ring, work with experts who understand the demands of your application and can recommend the right sealing solution for you. They will be able to help you select a material that offers maximum resistance to wear, compression set and chemical attack.