METHOD AND DEVICE FOR PREVENTING GUIDE SHOE FLAW OF SEAMLESS STEEL PIPE

摘要

PURPOSE:To prevent the guide shoe flaws produced on the surface of a round steel material or a blank pipe which is a raw material in the stage of producing a seamless steel pipe by a Mannesmann process, by interposing mill scale between the material to be rolled and guide shoes during rolling. CONSTITUTION:In the stage of piercing or rolling a round steel billet or a blank pipe 12 with a plug 2, when a switch mechanism 8 is turned on, a cylinder 7 operates and a regulating body 9 ascends. Then, the mill scale 6 in a vessel 5 is dropped on an inclined bottom plate 15 into the space of a hanger 11 and interposes between the abutting surfaces of the raw material 12 inserted between rolls 3, 3 and guide shoes 4, 4 and the shoes 4. The cracks, flaws and the like on the surface of the material 12 can be polished away by this in accordance with the rotating motion of the material 12. Upon completion of the rolling, the mechanism 8 is turned off, and the body 9 is lowered to cease the supply of the scale 6.