Method and apparatus for making pipe line steel grooved-end fittings
US5979202A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1997 |
| Grant date | Nov 9, 1999 |
| Priority date | — |
| Expiry date | May 29, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49444
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for making a grooved-end pipe fitting from standard pipe includes the steps of bending length of pipe on a press mandrel to form a curved pipe segment with an oval cross section and further working the curved pipe segment in a die to produce tangent end portions. The die cavity is shaped with a central curved portion and tangent end portions. The inner and outer radii of curvature of the central curved portion are greater than the inner and outer radii of the curved pipe segment, and are greater than the corresponding radii of curvature of a conventional cast fitting. As a result, the curved pipe segment can be shaped to conform to the shape of the cavity without buckling or bowing of the inner radius wall of the pipe. The tangent ends of the die shaped pipe are grooved in a subsequent step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.