摘要 |
A process and apparatus for the production of seamless tubing incorporating a push bench is provided in which ingots are pierced in the longitudinal direction by diagonal rolls over the stopper rods of a piercing mill to provide pierced ingots having one end with a wall thickening which protrudes outwardly or inwardly, then the wall thickening ends reshaped to provide a partially closed end and finally the pierced ingots are forced through the roll passes of a push bench by mandrel rods engaging the partially closed end so that the ingots are formed into a tube bloom.
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