The temperature within the oil seal environment is the main factor that dictates the composition of an oil seal. Generally, there is a range of set temperatures that are optimal for that material. If the operating environment is too cold, the seal may become brittle and, at high temperatures, the seal material may show increased elasticity and become leaky.
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Examples of allowable total eccentricity for oil seals
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The Importance of Pulley Oil Seals A Necessity for Optimal Machinery Functionality
A standard oil seal consists of an outer circular metal disk with an inner flexible rubber which is affixed to the metal during vulcanization. The bonded seal has no loose parts to allow leakage of oil or ingress of any contaminants. This kind of seal is more accurate, and can easily be fitted into a smaller space. An example is shown in Figure 2.9.