| 摘要 |
A method of manufacturing a seamless steel pipe including the steps of: providing a hollow billet with a mandrel inserted therein and forging the hollow billet into a primary hollow shell of a predetermined diameter and thickness; subjecting the primary hollow shell to diameter reduction at one end portion thereof; and providing the primary hollow shell with a mandrel inserted therein, the primary hollow shell having the diameter reduced portion at the one end portion thereof, and subjecting the primary hollow shell to push-drawing using a push bench. With this method, it is possible to manufacture seamless steel pipes of a wide range of manufacturable sizes (large diameter or thick-walled pipes) with high dimensional accuracy, particularly with high wall thickness accuracy. |
