Making preformed blanks - for subsequent forging to gate valve bodies

摘要

Gate valve bodies are drop forged from a blank that has been preformed by some other process such as forging, followed by rolling or expanding, to give the preform the required height and wall thickness. The final body can then be bored through for pipe connections to be welded on and seatings inserted inside. The process allows the mfr. of valve bodies normally difficult to drop forge direct if the dia. is less than the height.