Ovako develops durable, sustainable coating for hydraulic piston rods
Ovako has introduced NiKrom III, a sustainable coating for hydraulic piston rods offering an alternative to traditional hard chrome plating. The company reports successful trials in demanding environments, including in mining operations.
Steel manufacturer Ovako has launched NiKrom III, a new coating designed to enhance the corrosion resistance and durability of hydraulic piston rods, addressing the industry's increasing focus on sustainability.
The previous standard for protecting hydraulic piston rods in challenging conditions was hard chrome plating. However, growing environmental pressures and stricter regulations have driven the need for alternatives. NiKrom III is a duplex coating, combining a nickel underlayer with advanced trivalent chrome (CrIII). This provides an alternative to hexavalent chrome (CrVI), a substance restricted under REACH directives.
Ovako states that NiKrom III can be integrated into existing production systems and offers high durability, corrosion resistance, and wear protection. It is suitable for components exposed to harsh environments, such as those used in mining, offshore, and chemical plants. Sandvik Mining and Rock Solutions, for example, has successfully tested the coating under extreme conditions in mining operations.
The new coating was developed in collaboration with chemical industry partners. Its production process requires careful control but yields a highly durable surface. Ovako claims NiKrom III possesses similar surface structure, hardness, and friction properties to traditional chrome products, enabling its use with existing sealing designs without compromising mechanical properties or weldability.
In trials conducted by Sandvik Mining and Rock Solutions, NiKrom III coated cylinders demonstrated up to five times greater corrosion resistance compared to standard cylinders in saline mining environments. Sandvik now offers NiKrom III as an option on selected cylinders and anticipates an increase in its adoption.