skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Method and apparatus for restoring tubular upsets

Patent ·
OSTI ID:6311358

This patent describes a joint extension for oil well drill pipe tubular members having enlarged diameter upset end portions carrying respectively pin and box threaded sections, comprising: a. an enlarged tubular body having an outer surface, a flow conveying bore, and the first and second male and female threaded respective pin and box portions at the ends; b. a first beveled peripheral annular shoulder on one end of the tubular body, extending radially from one of the threaded sections to the outer surface of the upset end portions; c. a second beveled peripheral annular surface extending from the upset end portion outer surface to the other of the threaded sections; d. one of the threaded sections being damaged in the thread area and with the damaged portion removed, the body member is provided with additional thread in the remaining upset portion; and e. a cooperating threaded extension member, including a cooperating annular shoulder that registers with the first annular shoulder upon assembly to close the bore to define an external recess. The external recess defines an annular weld groove that is sealed with a butt-type annular weld having an outer diameter substantially equal to the outer diameters of the engaged additional threaded end portion. The threaded extension member is at the upset portion.

Assignee:
NOV; NOV-87-071026; EDB-87-137682
Patent Number(s):
US 4676528
OSTI ID:
6311358
Resource Relation:
Patent File Date: Filed date 29 Apr 1986
Country of Publication:
United States
Language:
English