Surface treatment offers stronger, greener chain

A range of chain products has been launched that offers the same strength and wear resistance as standard carbon steel chain but which has a unique 'double barrier' against corrosion. Tsubakimoto's 'DP' chain, which was introduced last year to the UK market, also benefits from having no chromium content and so is kinder to the environment. But surface treatment of the chain is where the company believes it has the edge over competing products. Robert Young, UK marketing manager at the company told Eureka: "In tests, DP chain endured salt-water [brine] spray for more than 500 hours, offering five times the anti-corrosion performance of zinc-plated chain and 20 times the performance of nickel-plated types." He explained that with nickel-plated chain, if users damage it, it starts to peel off in strips and is hard to control once the damage has been initiated. "With DP chain, we've developed a surface treatment that, if damage is done to a certain area of the chain, it remains localised at that point and does not continue to peel off all along the surface of the chain." While Young understandably chose not to reveal the secret ingredients behind the new surface treatment, he did hint that the specially-developed top coat protects the chain from physical impact and corrosive agents. This is backed up by a zinc base coat through a unique 'sacrificing' function that prevents oxidisation from reaching the chain core. He said the low temperature process required no acid wash, so the strength of the chain and wear life was maintained. On the green side, DP chain has a chromium-free coating, so plant environments and operators are not exposed to the risk of hexavalent chromium, a known carcinogen that can be harmful if inhaled or absorbed. The use of chromium as a surface treatment material is gradually being restricted. The chain comes in roller and conveyor versions and is resistant to acid rain and other adverse weather conditions. This makes it suitable for outdoor applications such as car washes, case washers, seafood processing machines, water treatment plants and other utility applications. According to Young, the chain is also equally suited to indoor use on equipment such as industrial washing plant, canning lines, bottling lines and food processing applications, where the product does not come into direct contact with the chain.