摘要 |
A method of producing a piston for a compressor, including the steps of casting a molten material into a die to form a hollow cylindrical head portion of the piston that is open at one of opposite ends thereof and is closed at the other end thereof, such that an amount of gas included in the material of the head portion is not more than 5 cc per 100 g of the material, closing, with a closure member, the open end of the head portion, and welding the head portion and the closure member to each other by emitting, a plurality of times, a welding beam toward each of a multiplicity of spots on a welding line along which the head portion and the closure member contact each other.
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