DBM piston seals

The DBM is a multi-part double-acting piston seal, fitted on a one-piece piston. In the centre is the sealing ring; on each side there is an anti-extrusion ring, which stops the centre ring being pushed into the gap, and a guide ring, which centres the piston in the barrel and takes the side loads.

There are more than 140 sizes, from a 20 mm bore, given as bore × groove diameter × width, with the ring height after the slash (for example 25x15x12/4).

To choose, measure the bore, the groove diameter and the groove width on the piston, or the old seal, and check all dimensions before ordering.