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Copper sleeve, also known as copper shaft sleeve, is divided into various types, including machine copper rollers, copper bearings, etc. Used in various light, large, and heavy machinery, it is an important component of machinery. The product has the traditional function of tin bronze bearings, which are made of electrolytic copper as raw material mixed with various trace metal elements, sintered at high temperature, and processed by air pressure centrifugal casting. High hardness, excellent wear resistance, less prone to biting, good casting and cutting performance, and good corrosion resistance in the atmosphere and fresh water. In the absence of lubricants and the use of water-based lubricants, the sliding and self-lubricating properties are good, easy to cut, poor casting performance, and good corrosion resistance to dilute sulfuric acid. General purpose structural components, castings with simple appearance used in ships, instruments, etc., such as sleeves, bushings, bearings, sliders, etc.