With the development of more mixed modification engineering plastics raw materials, the heart parts of extruder not only have higher wear resistance, but also more corrosion resistance.As a response, the bushing often requires the use of tungsten carbide particles to strengthen the nickel base material, and the cost will be significantly increased if the integral alloy elliptical liner is simply used.So we developed a third of the "double metal elliptical inner bushing", effective alloy layer thickness is 1.5 mm or so only can greatly satisfy) cylinder to both the requirements of the service life of the wear resistance and corrosion resistance increase, especially applied to the inner hole is more than 60 mm). RX101A alloy bushing is developed by our company specially for the screw extrusion lining sleeve material, this material has excellent anti-wear property and corrosion resistance, high cost performance, the use of more than ten years more than four thousand sets of equipment.