Hitachi Automotive Systems Akita Plant manufactures power steering units for automobiles. The plant introduced an abrasive powder compression system with the aim of recycling marketable materials from the polishing sludge generated during the processing of parts called racks. These are parts that enable tires to turn by transmitting the force of turning the steering wheel into horizontal movement. About 360 tons of polishing sludge that had been disposed of as industrial waste annually are now recycled and sold as a material for steel frames. The cutting fluid—which accounts for about 53% of polishing sludge—extracted during the compression and solidification of polishing sludge is now reused in production lines. As a result of these efforts, the process has produced no polishing sludge since fiscal 2018, eliminating waste processing costs, and purchases of cutting fluid have also been reduced.
