Patent · US Expired

Method for interconnecting tubulars by forge welding

US7199325B2 · kind B2 · utility

4Cited by
20References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 2002
Grant dateApr 3, 2007
Priority date
Expiry dateFeb 26, 2023

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K20/14
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method for interconnecting tubulars by forge welding involves arranging the tubular ends that are to be interconnected at a distance, up to a few millimeters from each other in a shield gas chamber, into which a reducing non-explosive flushing fluid mixture (e.g. N2+H2) is injected; heating each tubular end within the space by means of at least three electrodes that are pressed at circumferentially spaced intervals against the wall of each tubular, adjacent to the tubular end such that a high frequency electrical current is transmitted in a substantially circumferential direction through the tubular segments between the electrodes; and moving the thus uniformly heated tubular ends towards each other until a forge weld is formed between the heated tubular ends.

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