Rubber oil seal
A wide range of sealing devices are used in various machines.
Sealing devices serve the following functions:
RS

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PTFE
These are comparable to type R and RST, except the outer case does not have a metal reinforcement ring. To compensate, the outside is not made of normal rubber, but a hard, heavy-duty rubber fabric. The advantage is that these types can be made in a split version. They are almost always produced to order, and made of NBR or FKM.