Corresponding sealing devices will be installed on both ends of the rolling bearing. With a dust cover and a sealing ring, the two performances are different, one is dust-proof and the other is sealed. What are the common materials for this sealing device? There are mainly the following types.

Nitrile rubber

Nitrile rubber is a universal sealing material, which is a rubber synthesized from acrylonitrile and butadiene, and has good resistance to the following media:

Most mineral oils and lubricants based on mineral oils, general fuels such as gasoline, diesel, and light civilian fuels, animal oils, vegetable oils and fats, and hot water.

Nitrile rubber seals also allow bearings to operate for short periods of time without oil. The allowable working temperature range is -40 to 100 ℃. It can withstand temperatures up to 120 ℃ in a short period of time. But it is not suitable to operate at higher temperatures, as nitrile rubber will harden.

Hydrogenated nitrile rubber

Hydrogenated nitrile rubber has better wear resistance than nitrile rubber, so seals made from this material have a longer working life. In addition, hydrogenated nitrile rubber has stronger heat resistance, aging resistance and hardening resistance in hot oil or ozone. Hydrogenated nitrile rubber allows a maximum working temperature of 150 ℃, which is much higher than the working temperature of nitrile rubber.

Fluororubber

The main characteristics of fluororubber are high temperature resistance, chemical corrosion resistance, good anti-aging and ozone resistance, and low air permeability. Even under extremely harsh working conditions, fluororubber still has excellent wear resistance. It can withstand working temperatures of 200 ℃ or below. The seal made of this material allows the bearing to operate for a short period of time without oil.

Fluororubber also has excellent resistance to various media, including oil and hydraulic oil, fuel, lubricants, inorganic acids, aliphatic hydrocarbons, and aromatic hydrocarbons. Fluororubber should not be used in the presence of esters, ethers, ketones, certain amines, and high-temperature anhydrous hydrogen fluoride compounds. If the sealing components made of fluororubber are exposed to open flames or high temperatures above 300 ℃, it will endanger health and the environment! Even after cooling, they still pose a danger.

The function of seals is to prevent lubricant loss and prevent contaminants from entering the space that needs to be protected.

Characteristics of bearing sealing device

Having sufficient deformability to compensate for irregular surfaces;

Having sufficient strength to withstand pressure during work;

Capable of withstanding a wide range of operating temperatures.