Forming profiles on internal or external surfaces (making screw-thread by forging, pressing, or hammering B21K)

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Methods for forging, hammering, or pressing (for working sheet-metal or metal tubes, rods, or profiles B21D; for working wire B21F); Special equipment or accessories therefor > for performing particular operations > Forming profiles on internal or external surfaces (making screw-thread by forging, pressing, or hammering B21K)