Abstract: A steel pipe drawing apparatus, which can manufacture a drawn steel pipe which is a long object with high accuracy and at high speed as well as improves dimensional accuracy of respective thick-wall portions and cutting positions of the drawn steel pipe, is realized. When a stepped drawn steel pipe is manufactured by moving a die and a plug relatively in the same direction as a steel pipe drawing direction and in an opposite direction thereto, a first hydraulic cylinder moves the die relatively in a direction corresponding to the steel pipe drawing direction, and a second hydraulic cylinder moves the plug relatively in a direction opposite to a moving direction of the die. At this time, a position detecting sensor detects a stroke position of the second hydraulic cylinder, and a computer receives positional information detected by the position detecting sensor and controls a moving velocity of the second hydraulic cylinder.

Abstract: A method of and a device for cold drawing seamless metal tubes, each tube having an upset portion on both ends. The draw bench comprises a reducing die, a die control unit, a plug control unit including a plug and a draw unit. The reducing die has an internal surface including an inlet portion which tapers rearwardly, a small diameter bearing portion and an oppositely inclined outlet portion. A plug includes a rearwardly tapered portion, a large diameter bearing portion, a forwardly tapered portion, a small diameter cylindrical portion, a rearwardly tapered portion and a large diameter cylindrical forward bearing portion. The plug control unit is mainly movable with respect to the die control unit by a pair of hydraulic units, but the control unit is also movable with respect to the plug control unit for changing a cross sectional reducing area between the reducing die and the plug.

Abstract: A draw bench for cold drawing seamless middle tubes having upset portions on both ends. The draw bench includes a die control device, a plug control device including a plug having large and small diameter bearing portions and a draw unit. The die control device and the plug control device and the plug control device are moveable with respect to each other for changing the cross-sectional reducing area between the reducing die and the plug.