Grease lubrication is generally restricted to relatively slower-speed applications due to reduced capability for frictional heat dissipation as compared with that of oil.
The advantages of grease over oil are 1.) It simplifies seal design, acts as a barrier to contamination and is a sealant. 2.) It permits pre-lubrication of sealed or shielded bearings, 3.) It generally requires less frequent lubrication, 4.) It has a simplified application system design and is less costly.
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