Electropolishing for the Hydraulic & Pneumatic Industries
With all the automation technology used in the world today, there has been a huge increase in the use of hydraulic and pneumatic assemblies. From robotics to heavy mobile equipment, the applications are numerous. For reliability and high cycle life, the components in these assemblies must be precisely machined and have the proper surface finish. To achieve the desirable finish, many companies have turned to electropolishing. Our electropolishing is compatible with nearly any alloy and uniformly removes material from the surface lowering the Ra value. In addition, electropolishing removes burrs and any flecks of metal or contaminants that may be present from machining. It is critical that the components used in these industries be clean so not to interfere with the functioning of the assembly. Premature failure due to contamination can lead to equipment being idle and lost production time.
Since the early 1980’s we have been electropolishing various parts for a customer who specializes in manufacturing hydraulic components and control systems. The plungers, spools and pins we electropolish are machined from carbon steel and 300 series stainless steel. The customer has specified that this family of parts be sent to Able primarily for deburring. Their specification includes the amount of material removal to insure that the parts are burr free while keeping the corners sharp. After electropolishing the parts are packed in cell trays to avoid part to part contact during shipping.
We electropolish another item that is a sleeve made from 416 SS. This particular part is used in a pneumatic application and our customer was looking for a way to deburr the inside and outside diameters. The part has holes throughout with multiple “o” ring grooves on the exterior. The sleeve is assembled with a spool that fits into the inside diameter. Due to the tight clearance between the two parts, it is imperative that the ID of the sleeve be free of burrs and sharp edges along with other contaminants from machining. Any foreign material present in the ID will cause the valve to malfunction and wear prematurely. When electropolishing their part we remove approximately .0002” material from the ID. Able constructed the tooling in house which included a bipolar rack to be able to place an electrode through the entire ID. Due to the critical nature of the part and special handling required, we utilize special carriers with dividers designed to transport the sleeves from the electropolishing tank through the multi-stage rinsing operation.
Over the years, we have been successful in electropolishing poppets for multiple customers. One of our customers sends us poppets in various sizes machined from carbon steel. After final grinding, the parts are sent for electropolishing to improve the surface finish and to remove any loose flecks of material. For this application, our engineering record is set-up to remove .0005” from the diameter. As a precautionary measure, after electropolishing we apply a light rust inhibitor prior to packaging in plastic cell trays for shipping. Many of our customers use plastic cell trays to package their parts. The cell trays are inexpensive and effective in protecting the parts during transit to and from Able.