Chrome plating, also known as hard chrome, is a technique of electroplating that applies a thin layer of chromium onto a metal object. Chrome plating is used to provide a working surface that requires one or more of the following characteristics: to reduce friction, resist abrasion, or increase corrosion resistance. It is very hard, measuring between 66 to 70 HRC. Surface defects and roughness are amplified because hard chrome does not have a leveling effect.
Friction between a cylinder rod and its seals, and the resulting wear, has a crucial influence on the efficiency and service life of a hydraulic cylinder. Chrome plating is a cost-effective repair option that can allow salvage of a cylinder rod, cylinder tube, or valve spool instead of replacing it with new.
In addition to the cost benefits, chrome plating also creates a hardened wear surface, extending the life of most high wear areas resulting in longer run times between repair or replacement of shaft seals. It can also be used to build thickness on bearing journal areas as well as, valve spools to ensure proper fit when the housing needs to be honed to remove scoring.
Chrome plating is recommended in cases where existing chrome is damaged, worn through to the base metal, scored or dented. Cylinder rod damage can allow contaminants to enter the hydraulic system which accelerates seal wear and eventually cause internal leaks. Chrome plating restores the cylinder rod surface to like-new condition or in some cases better than OEM specifications.
After the chrome is stripped from the damaged part, repairs, if needed to base metal, can be made to include welding and grinding of any imperfections. After any necessary repairs are made, the part then goes through the extensive chrome plating process.
In tough work conditions, the cylinder rods are usually exposed to extreme environments. Consequently, a high quality, protecting layer of chrome on rods with good toughness, corrosion protection and wear resistance is crucial for hydraulic cylinder performance.