佛山正大机电轴承有限公司

The task of guide rings and guide strips of plastic materials is to guide the piston in the cylinder bore and the rod in the cylinder head in a working hydraulic cylinder as well as to withstand arising side loads and prevent metallic contact between these axially mobile parts.

Plastic guides have been used instead of metallic guides for several years now which has resulted in a considerably longer service life for hydraulic cylinders. Plastic materials work more smoothly against the cylinder tube and the sealing surface of the rod, although contamination particles often are included in the hydraulic oil.

Metal guides are only slightly deformed also at heavy loads which implies that the force is concentrated to small areas. The speed in a hydraulic cylinder is also very low from a guide function point of view which results in an insufficient lubrication. This condition in combination with the presence of contamination particles result in a rapid wear of the metal guide, the cylinder tube and the rod surface.

From a mechanical point of view, the main advantage with a plastic guide in comparison with a metal guide is illustrated in fig.