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First, the friction welding of the piston rod is relatively low in cost because it only needs to consume an appropriate amount of electricity and does not require any flux.

Second, the overall efficiency of the welding is high, and the welding can be completed in two or three minutes.

Third, the welding piston rod is better in quality, and the strength of the weld is close to the mother.

Fourth, there will be no sources of pollution such as light, sound, gas and radiation.