Features and applications
Corrosion protection on a hydraulic cylinder works at two distinct levels. The first level protects the rod only: on the standard CD/DK/MD tie-rod series, the rod can be ordered in corrosion-resistant materials such as chrome-plated stainless steel or Nikrom-coated steel, while the cylinder body keeps its standard finish. The second level protects the whole cylinder: the CDNI version adds an electroless nickel plating to the cylinder itself — the plating is a treatment of the cylinder, not of the rod — combined with a chrome-plated stainless steel rod. This is the configuration for the most aggressive environments, where detergents, chemicals or salt spray attack every exposed surface, not just the rod.The electroless nickel layer is 20 µm thick, with high adhesion and a uniform coating across the machined surfaces. Corrosion resistance is verified at 1200 hours in salt spray testing, rating 10. The process contains no heavy metals and no ammonia, for a low environmental impact. For many applications, a CDNI cylinder is a practical alternative to a cylinder made entirely of stainless steel.
Typical cases: food and beverage plants where machinery is washed down with aggressive detergents and a painted surface is not acceptable; coastal or marine installations exposed to salt-laden air; process areas in contact with substances that promote corrosion; washing and cleaning lines with frequent wet cycles.
