(1) welding. Including: (non surfacing parts can be repaired with wear and after welding can be processed to the original form (parts), spot welding can save connecting fasteners and local scratches, welding, polishing) welding (wear compensation) plasma welding, spontaneous combustion welding (for field work). (2) brush plating, also known as bath plating. This is a mature technology that has been used for 30 years and can be used to repair local wear of parts, especially large parts, with simple facilities. In recent years, brush plating technology has made new progress. For example, the nano brush plating technology can greatly improve the mechanical properties of the coating. (3) spraying technology. It can not only compensate the wear and tear of parts, but also improve the surface performance of parts. For example, special materials are sprayed on different base materials to achieve corrosion protection, wear resistance and other effects. Spraying technology is developing very fast now. February 2004, The Academy of Armored Forces Engineering Equipment Remanufacturing Technology National Key Laboratory of science and technology research project "high performance" research and application of supersonic plasma spraying, awarded the 2005 National Technology Invention Prize and two national science and technology progress prize two. In addition, cold spraying has appeared in recent years (thermal spraying has its disadvantages: spraying material is oxidized). (4) stick coating technology. Composite materials using polymer or inorganic compounds with special filler and coating on the worn parts surface to be machined after curing, can restore the size and precision of parts, to achieve the original performance. This method is especially suitable for the repair of large parts. For example, Xuzhou construction machinery group company applied coating technology (resin and curing agent, 24 hours after processing) to exclude 500t press cylinder (phi 500mm * 1300mm) the inner wall of large area wear, resulting in serious fault oil drainage decompression cylinder between. The cost of the repairs is only 1/20 of the replacement cost. (5) bonding technology. Bonding technology includes bonding material and bonding process. At present, bonding material has formed a family, which is divided into several series according to adhesive materials and uses. Each series is divided into different specifications and widely used. Typically Germany, there are more than 900. The bonding strength is not less than the base metal strength. For example, A380 aircraft, 1/3 of the parts are glued together. In addition, SMT technology has been developed (Industrial wound patches used to repair pipeline leaks).