Oil seal specifications
Oil seals work by squeezing and retaining lubricant in a thin layer between the lip and the shaft. Perfect sealing is ensured by the hydrodynamic action of the rotating shaft, which in turn produces a slight pump action.

When selecting a natural rubber gasket for your specific application, there are several key factors to consider. The first is the hardness of the gasket, which is typically measured on the Shore A scale. A softer gasket (lower Shore A hardness) is more flexible and better suited for applications where the sealing surface is uneven, while a harder gasket (higher Shore A hardness) provides better resistance to compression and extrusion.
There is a little leakage as the fluid vapors get released into the atmosphere from the faces of the seal, though. Since the quantity is hardly quantifiable, the seals are considered leak proof.
Oil seals come with various lip designs, each serving a unique purpose and suitable for different applications. Let’s discuss the most common industry-standard lip designs:


One of the key advantages of the 40mm rubber gasket is its flexibility and resilience, allowing it to conform to irregular surfaces and maintain a tight seal under varying conditions
. This property makes it an ideal choice for sealing joints, flanges, and connections in industrial equipment and machinery.40mm rubber gasket

(This facilitates mounting.)

synthetic rubber gasket.
MH: O.D. wall is a rubber material
HM: O.D. wall is a metal case
MH(S)H: O.D. wall is metal with a reinforced inner metal case
The perfect solution to this is to always use an oil seal that fits properly; the right size of the seal should be used. And in other cases, backup devices should be used to avoid the buildup of clearance gaps within the mating edges.