Guide rings

Guide rings (wear rings) guide the piston and rod of a hydraulic or pneumatic cylinder and protect the seals against side loads. We have more than 550 items in stock for diameters from 15 mm to over 200 mm.

Materials: POM (polyacetal) for normal loads, polyester fabric with phenolic resin and PTFE for high loads, and aramid with phenolic resin. The size is given as inside diameter x outside diameter x height and profile type – e.g. 40 x 46 x 9.6 K68 POM. Brands Kastas (profiles K68, K69, K73, K78), Simrit and Seal Jet. Guide rings in stock are shipped immediately, delivery within 1–2 days.

Frequently asked questions

What does a guide ring do in a hydraulic cylinder?

A guide ring guides the piston in the cylinder tube and the rod in the cylinder head and absorbs side loads. It prevents metal parts from touching and so protects the piston and rod seals against overload and wear. That is why guide rings are replaced together with the seals when a cylinder is repaired. We stock rings for both piston and rod, the Kastas K78 profile is designed for both uses.

Which guide ring material should I choose?

For normal loads, guide rings made of POM (polyacetal) are sufficient. For high loads there are guide rings made of polyester fabric with phenolic resin and PTFE, and we also stock rings made of aramid with phenolic resin. The material is stated in the name of each item, for example 40 x 46 x 9.6 K68 POM. The simplest choice is the same material as the original ring.

How do I find the size of a guide ring?

We state the size in mm as inside diameter x outside diameter x height and profile type, for example Kastas K68, K69, K73 or K78. For a ring on the piston the outside diameter equals the cylinder bore, for a ring in the head the inside diameter equals the rod diameter. The height is the groove width. If you cannot find the size you need, send us the designation and we will check whether we can supply it.

What is the difference between a guide ring and a guide strip?

A guide ring is a finished ring for a specific piston or rod diameter. A guide strip is cut to the required length and inserted into the groove of the piston or cylinder head, its size is given as width x thickness. Choose a strip when no ring is available in the required diameter or when you want to stock one material for several diameters. Guide strips are in a separate category.

How fast can you deliver guide rings?

We stock more than 550 guide rings for diameters from 15 mm to over 200 mm from Kastas, Simrit and Seal Jet. Guide rings in stock are shipped immediately and delivery takes 1–2 days. Current availability is shown directly for each size. Together with the guide ring you can order the piston and rod seals for the same cylinder.