Common Types of Oil Seal Materials

What is an oil seal?
Seals are critical for safeguarding the bearings of any rotating shaft assembly. They prevent impurities like dirt, dust, and water while also conserving the system's lubrication.

Choosing the Right Oil Seal
Oil seals are available in a variety of kinds and materials, depending on their purpose. Determining the material is critical to ensure that your equipment operates at peak efficiency. For example, if your equipment has to operate at higher temperatures, such as an engine seal for a jet engine, you may need to select a specific material to ensure that your oil seals function effectively. In this post, we will look at the most often used materials in the business, as well as some of the more unusual possibilities available.
 

Oil seal materials

Nitrile

The first substance that we'll look at is Nitrile Buna-N 70, or NBR for short.

The majority of conventional applications are advised for NBR, which is the most often used rubber (elastomer) substance. This is because Nitrile is compatible with most settings and is reasonably inexpensive. Nitrile is often used in disposable nonlatex gloves, footwear, automobile transmission belts, synthetic leather, hoses, o-rings, gaskets, oil seals, and other applications.
 

Nitrile has a temperature range of -35° to 120°C (-30° to 250°F). NBR seals are suitable for a wide range of applications, including gas oil, silicone oil, animal/vegetable oils and fat, hydraulic liquid, and hot and cold water. Furthermore, NBR is grease and abrasion resistant, making it a great choice for any application requiring shock absorbers.


NBR's shortcomings include low ozone, UV, and weather resistance, as well as inadequate high temperature and flame resistance. Silicone is far superior than other materials in terms of temperature resistance.

Silicone

The conventional operating temperatures of silicone compounds, often known as "VMQ," range widely from -60°C to 200°C (-140°F to 392°F).

Its exceptional resilience to temperature is matched by its resistance to light, ozone, and weather. Pneumatics, hydraulics, and the food and medical industries are among the industries that often use silicone. Because of its flexibility and translucency, it is frequently used for electric insulators but is also the material of choice for o-rings, molded components, and flat seals.

While silicone is incredibly flexible, it does have several drawbacks. Poor tensile strength, rip resistance, and abrasion resistance are common characteristics of silicone compounds. Look no farther than Viton® if you're searching for a material that provides both great temperature resistance and a higher tensile strength.

Viton®

The Chemours Company owns the trademark for Viton®, a particular kind of synthetic rubber that is frequently used in o-rings, oil seals, gaskets, chemical-resistant gloves, and other molded goods.

Viton is the best material for applications requiring higher temperatures because of its greater density, which allows it to withstand temperatures ranging from -40°F to over 400°F (-40°C to over 240°C). Additionally, Viton® offers the broadest spectrum of chemical resistance; it can withstand methanol fuels, silicone oil, mineral/vegetable oil, aromatic, chlorinated, and non-flammable hydrocarbons, among other substances.

While it does outlast other materials in terms of wear durations and tensile strength, it is advised to use it sparingly or sporadically in dry-running applications.

Viton can be more costly than other materials, although having a better temperature and chemical range than the others. Now let's look into Polyacrylate, a less expensive alternative.
 

Polyacrylate offers an excellent balance between price and performance. Its temperature and chemical range performance is good, but not as good as Viton's. The temperature is between -25°F and 300°F, or 31°C and 148°C. Because polyacrylate has a strong resistance to hot oil and oxidation, it is mostly employed in automobile gearboxes and hoses but is also present in shaft seals, gaskets, and o-rings. Although polyacrylate is a cost-effective substitute for more costly polymers resistant to high temperatures, its water compatibility and cold flexibility are lacking. An atmosphere that is resistant to heat and oil is ideal for polyacrylate, while cost is the main concern. Additionally, even though there are many uses for these four distinct materials,Even more resources are available that are tailored to extremely narrow markets.
 

In brief

Perfluoelastomer oil seals are the greatest temperature-resistant options available, with a melting point of up to 600°F. Chloroprene is most frequently used for refrigeration since it can withstand temperatures as low as 40°F, which is very concerning. And Butyl, the all-petroleum molecule, is your best bet if FDA applications or medical devices are your main concern. As you can see, selecting the appropriate material to work with requires careful consideration of a number of other important factors.

You should now have a better idea of why selecting the appropriate materials for oil seals is crucial after reading this article. Remember that we would be pleased to assist you with any inquiries you may have regarding industrial oil seals and supplies.