The type of seal material used should given a lot of consideration when choosing an O-ring for your application. It is crucial to choose an O-ring material that best suits the operating conditions of your application. Because proper sealing action is heavily dependent on the state of your O-ring, Nitrile rubber, also known as Buna-N, Viton (r), silicone rubber, neoprene, and PTFE, or Teflon (r), are a few materials widely used to produce O-rings for different applications.
The operating temperature range that standard O-rings are subjected to and the many chemicals they may be exposed to are two of the most important factors to consider. When selecting an O-ring material. Resistance to ripping and abrasion, as well as sunlight or aging, are some other aspects that are into consideration when choosing an O-ring material from a standard O-ring supplier.
Each material has pros and cons since different environments and chemicals affect most O-ring materials differently.
Nitrile Rubber:
Buna-N, a synthetic rubber copolymer, is one of the materials most commonly used to make O-rings. It’s also called nitrile rubber. Water, hydraulic fluids, solvents, oils, and other petroleum products don’t harm this material at all. Nitrile rubber is one of the mostly used elastomers to make O-ring seals by an O-ring supplier . Along with its operating temperature range of between -65 degrees F and +275 degrees F.
Nitrile has several limitations, and is typically not recommended for applications where it might be exposed to ozone, sunlight, and chemicals, including ketones, esters, and aromatic hydrocarbons. Nitrile rubber seals must also be kept away from electric motors that typically produce ozone due to their ozone sensitivity.
Nitrile rubber O-rings have become the choice for numerous applications in the automotive industry. Due to their great resistance to petroleum products and fair enough resistance to temperature.
Viton(r):
Another synthetic rubber that is mostly used to make O-ring seals is Viton (r). This elastomer is a favorite for usage in a variety of applications. As well as its resistance to wide operating temperature ranges. Seals manufactured of this material have been found to survive temperatures as high as +600 degrees F for brief periods of time, despite their operating temperature range of -10 to +400 degrees F. Viton is a great option for high-temperature applications as well as applications exposed to a variety of fluids because of its mix of properties. SCUBA diving is one such application that makes use of Viton O-rings, in which the O-ring seals are found in the air tank of the diver. Viton is often incompatible with ketones and organic acids, even though it is compatible with the majority of hydrocarbons.
PTFE:
One fluoropolymer that is quite frequently used to make O-rings is PTFE, also known as Teflon (r). It is one of the most chemically inert materials used to make O-rings and has a high level of resistance to a wide range of chemicals. Including oils, solvents, bases, acids, steam, and others. It is perfect for dynamic sealing applications due to its unmatched resistance to abrasion and tearing.
The use of PTFE O-rings does have a few limitations, though. First, they cannot be compressed, as can other materials used to make O-rings. Which results in ineffective sealing. Poor cold flow properties under constant strain are this material’s second significant drawback. Nevertheless, it has become a well-liked sealing option in many valves and other applications due to its chemical resistance and low coefficient of friction.
Neoprene:
Neoprene is another synthetic rubber that is mostly used by the metric O-ring supplier to make O-ring seals of specified sizes. Animal and vegetable fats, most oils, and solvents won’t harm this elastomer. However, it is normally not recommended to use this material’s O-ring seals in applications where they will be exposed to ketones, esters, aromatic hydrocarbons, and potent oxidizing acids.
Natural Rubber:
O-rings made of natural rubber now rarely used because synthetic elastomers like Viton and Nitrile rubber have become common. Most oxidizing chemicals, animal oils, and vegetable oils can all used with natural rubber.
The Conclusion
Other materials, such as Kalrez, also used in some specialized applications. Although the materials listed above used elastomers for producing O-rings, In applications where the working temperature is up to 500 degrees F, Kalrez is a perfect substitute for Viton O-rings. Similar to this, different elastomers used for varied sealing tasks. You should take care to ensure that the material you decide to choose for your application is compatible.