Radial Lip Crankshaft Seals for Heavy-Duty Diesel Engines

New double-lip and dual-lip crankshaft seals for heavy duty diesel engines have been developed. The very low radial-load, double-lip design, incorporating a helix pattern, has been adapted for high speed (30 m/s) application. In this development, we established that the seal speed limit was reached when lip coking was generated due to breakdown of the oil.

A bonded dual-lip seal, which can endure speeds above 20 m/s, has been developed by adopting a unique ventilating system to release the negative pressure between the two lips. From this development, a new seal design concept involving PV values has been established.