Device for producing oil supply pipe and method for producing oil supply pipe

Abstract

A method for producing an oil supply pipe in which occurrence of cracks can be prevented at the time of forming a threaded portion in a metal pipe is provided. A method for producing an oil supply pipe in which a first rotating shaft 13 , a first circumferential surface 14 , and one first ridge portion 15 are provided, and in which, using a first forming roller 11 having the first ridge portion 15 spirally provided to have a length of less than one turn in a circumferential direction of the first circumferential surface 14 and a second forming roller 21 having a second rotating shaft 23 , a second circumferential surface 24 , and a second ridge portion 25 and the second ridge portion 25 spirally provided in a circumferential direction of the second circumferential surface 24 , a threaded portion formed of a spiral protrusion is formed in an inner circumferential surface of a metal pipe by inserting the metal pipe to the second forming roller 21 , disposing the first rotating shaft 13 and the second rotating shaft 23 so that they are parallel to each other, and pressing a material forming the metal pipe between the second ridge portions 25 using the first ridge portion 15 while rotating the first forming roller 11 and the second forming roller 21 is provided.

1 . A device for producing an oil supply pipe which forms a threaded portion in a metal pipe by disposing a first forming roller on an outer circumferential surface side of the metal pipe, disposing a second forming roller on an inner circumferential surface side of the metal pipe, and subjecting the metal pipe to roll forming using the first forming roller and the second forming roller, the device comprising:
 the first forming roller having a first rotating shaft, a first circumferential surface, and one first ridge portion spirally provided in a circumferential direction on the first circumferential surface to have a length of less than one turn; and   the second forming roller having a second rotating shaft, a second circumferential surface, and a second ridge portions spirally provided in the circumferential direction on the second circumferential surface,   wherein the first rotating shaft and the second rotating shaft are disposed so that they are parallel to each other, and   the first forming roller and the second forming roller are constituted to rotate.   
     
     
         2 . A method for producing an oil supply pipe which is a method for forming a threaded portion in a metal pipe by disposing a first forming roller on an outer circumferential surface side of the metal pipe, disposing a second forming roller on an inner circumferential surface side of the metal pipe, and subjecting the metal pipe to roll forming using the first forming roller and the second forming roller, the method comprising:
 using, as the first forming roller, the first forming roller having a first rotating shaft, a first circumferential surface, and one first ridge portion spirally provided in a circumferential direction on the first circumferential surface to have a length of less than one turn, and   as the second forming roller, the second forming roller having a second rotating shaft, a second circumferential surface, and a second ridge portion spirally provided in the circumferential direction on the second circumferential surface,   a preparation step of inserting the metal pipe into the second forming roller and disposing the first rotating shaft and the second rotating shaft so that they are parallel to each other; and   a formation step of forming the threaded portion formed of a spiral protrusion in an inner circumferential surface of the metal pipe by pressing a material forming the metal pipe between the second ridge portions using the first ridge portion while rotating the first forming roller and the second forming roller.