The size of the oil seal!

There are several commonly used letter codes for oil seals, each representing different characteristics of the Oil Seal: DS represents the Sealing lip of the bidirectional rotating shaft.

ZD represents two metal frameworks with inner and outer lips.
FB represents the lip shaped Seal of the rotating shaft of the exposed skeleton of the secondary rear.
SP represents the inner skeleton rotating shaft lip Sealing ring of multiple secondary lips.

MC represents shell type sealing ring.

The oil seal specifications and dimensions represent: W represents springless type, PD represents low-speed ordinary type, PG represents high-speed ordinary type, SD represents low-speed double port type, and DG represents high-speed double port type.

The expression method for oil seal specifications is dxDxH (inner diameter X outer diameter X height), which is measured in millimeters.

The function of oil seals is generally to isolate the components that need lubrication in the transmission components from the output components, so as not to let the lubricating oil leak.