Patent · US Expired

Inner grooving process for a metallic tube

US4876869A · kind A · utility

10Cited by
1References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 30, 1988
Grant dateOct 31, 1989
Priority date
Expiry dateJun 30, 2008

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB21C37/207
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

An inner grooving process for the tube expanding rolling type by which inner grooves such as wide width grooves or deep grooves which cannot normally be formed readily can be formed with a high quality using an equipment of a simple structure without deteriorating the operability. In the process, a drawing die having an exit hole of a fixed diameter and a floating plug having no bearing portion thereon are used. The floating plug and a grooved plug connected for rotation to the floating plug and having an outer diameter smaller than the diameter of the exit hole of the drawing die are inserted into a metallic tube and then the grooved plug is drawn to a location of the rolling member into the metallic tube by drawing and then retained at such location. The floating plug and the drawing die then cooperate with each other to reduce the inner diameter of the metallic tube to a dimension smaller than the outer diameter of the grooved plug and tube expanding rolling drawing is effected with a rolling member and the grooved plug thereby to expand and groove the metallic tube continuously.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.