The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 28, 1998
Filed:
Nov. 24, 1995
Thomas E Winship, Houston, TX (US);
Shaw Industries Ltd., Ontario, CA;
Abstract
A method for making an internal upset (20A) on metal drill pipe (10) having a transition section (24A) with a curved inner periphery (28A) of a concave curvature extending continuously between the central portion (12) of the pipe (10) and the increased thickness end section (22A) and formed from a radius (R2). An external upset (20) is first formed in forging steps as shown in FIGS. 2 and 4 by radially expanding and squeezing the end of pipe (10). Then the final forging step radially contracts the external upset (20) to form the internal upset (20A) as shown in FIGS. 3 and 5. The finished internal upset 20A as shown in FIG. 7 has a transition section 24A with an inner peripheral curved surface 28A formed from a radius (R2). The forging steps are performed with a single heating of the metal drill time in a minimum of time preferably within around one (1) minute but in any event less than around two (2) minutes.