The Problem

Ideally the piston or rod in a hydraulic unit should be guided exactly parallel to the cylinder wall. This is necessary in order to prevent one-sided or uneven loading of the hydraulic sealing elements, which can lead to premature failure or increased leakage of the hydraulic medium.

Relatively soft metals or alloys such as bronze are widely used for this purpose.
Abrasive dirt particles which get into the system settle between the metal surfaces of the rod or cylinder wall and the bronze, damaging the surfaces there.
Such damaged surfaces represent a greater tolerance which has to be compensated by a higher lip projection in order to ensure sealing at "0" pressure.
This in turn requires higher preloading of the lip, which however causes higher friction values and higher frictional temperatures. The results are faster seal wear and premature failure of the units.

The Solution

DEPAC guide rings were developed to prevent this chain of cause and effect from escalating.
They prevent the direct contact between metal and metal which leads to expensive repairs.
The resin composite material is reinforced with synthetic fibers and impregnated in addition to special lubricants for the lowest friction values.
Abrasive particles which may settle between the guide ring and the cylinder or rod surface are absorbed by the DEPAC guide ring.
The metal surfaces are not damaged.

The result is a long-lasting, undamaged metal surface of the rod or cylinder wall, thus guaranteeing reliable guidance for improved seal life even under "0" leakage conditions.

DEPAC guide rings are available in the following materials:

- POM or PA
- filled PTFE

Type DGF 1