In designing oil seals what is important is the type of rubber used as material oil seals must be oil resistance properties well under working condition. Important information for user-defined testing properties of materials used to make oil seals are as follows.
1. Type of oil such as lubricant , hydrolic oil.
2. Temperatue of oil at working condition
3. Pressure of oil at working condition
4. Shaft Speed (In the case of the rotating shaft)
The standard test used to test the resistance of the oil is ASTM D471 Standard Test Method of Rubber Property-Effect of Liquids. This test method only those failures caused to determine the likehood that an oil might cause premature sealing system failures in field use.
Measure
1. volume swell (% Volume Change)
2. excessive rubber hadening
3. elongation loss
4. Stress Relaxation
Testing of the material properties of the oil seals of NOK Oil seal material found that Viton® or Fluorocarbon (FKM) is the rubber has heat resistance. It also has excellent resistance to oil and chemical. It is the best rubber for oil seals due to its well-balanced charecteristics. However, this material is not resistant types of brake fluid (DOT 3 , DOT5 glycol base) refrigerants (R32 and R134a) Anti freeze Solution ans water stream.
