METHOD OF MANUFACTURING SCREW AND SECTION PIPES WITH HOLLOW SCREW CRIMPS Russian patent published in 2008 - IPC B21D15/04 

FIELD: technological processes.

SUBSTANCE: method includes forming crimps on the pipe, installed onto workholder with screw surface, using rollers, located around the longitudinal axis of the pipe, under action of axial force, applied to workholder section, remote from the rollers, and of torque, created by interaction of workholder and rollers.The torque is also applied to the section of workholder, which is adjacent to rollers, using a fairlead bush. Inner screw surface of the latter corresponds to screw surface of the workholder, and works in combination with it.

EFFECT: technological features increase, so does the quality of the product manufactured.

2 cl, 1 dwg