Piston rod construction
Wear and corrosion resistant surfaces are desirable on the outer diameter of the piston rod. The surfaces are often applied using coating techniques such as Chrome (Nickel) Plating, Lunac 2+ duplex, Laser Cladding, PTA welding and Thermal Spraying. These coatings can be finished to the desirable surface roughness (Ra, Rz) where the seals give optimum performance. All these coating methods have their specific advantages and disadvantages. It is for this reason that coating experts play a crucial role in selecting the optimum surface treatment procedure for protecting Hydraulic Cylinders.
Cylinders are used in different operational conditions and that makes it a challenge to find the right coating solution. In dredging there might be impact from stones or other parts, in salt water environments there are extreme corrosion attacks, in off-shore cylinders facing bending and impact in combination with salt water, and in the steel industry there are high temperatures involved, etc. There is no single coating solution which successfully combats all the specific operational wear conditions. Every technique has its own benefits and disadvantages.
Piston rods are generally available in lengths which are cut to suit the application. As the common rods have a soft or mild steel core, their ends can be welded or machined for a screw thread.