Hydraulic Seal Types Explained

Rod seals help prevent pressurised fluid escaping along the moving rod. Piston seals separate pressure chambers inside the cylinder.

Wipers help exclude dirt and moisture from the rod area. Guide rings support lateral loads and help prevent metal-to-metal contact.

Buffer seals can protect the primary rod seal from pressure peaks in some designs. Each component has a different role.

Select profiles using pressure, speed, stroke, temperature, fluid, clearances and hardware geometry. Incorrect installation can damage even a correctly specified seal.

Start with duty and dimensions

A request for a ‘cylinder seal at 250 bar’ does not identify a profile. Clarify rod or piston location, or whether you need a wiper, buffer or guide. Include rod/bore diameter, groove and seal dimensions, fluid, speed and temperature. A photo and drawing help when the profile is unknown.

Is the pressure value sufficient?

No. Extrusion gap, movement, compound, temperature and profile all matter. A system pressure value does not approve each individual seal.

General technical guidance, not approval for a specific application. Confirm material grade, dimensions and suitability for actual operating conditions.