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:
Sep. 17, 1991
Filed:
Jul. 27, 1989
Gerd Pfeiffer, Mulheim, DE;
Erich Quadflieg, Krefeld, DE;
Friedrich Lenze, Ratingen, DE;
Gerhard Krug, Duisburg, DE;
Josef Siekmeyer, Ratingen, DE;
Mannesmann Aktiengesellschaft, Dusseldorf, DE;
Abstract
A screwed pipe joint with a bell for connecting two pipes of a drill pipe string. The screwed pipe joint includes, in opposed relation, a first pipe having a first tapered threaded end (10) and a second pipe having a second tapered threaded end (11), the first tapered pipe end and the second tapered pipe end having a different taper and pitch, and being shaped so that when the pipes are joined they are form-locked and having an axial clearance (23, 23') therebetween; and a bell having a first and second threaded section (7, 8) complementary to and for engagement with the first and second threaded pipe ends, and an unthreaded section (9) therebetween and a radially inward projecting shoulder (24) on the unthreaded section (9) of the bell (6) opposite the first pipe (2); the first and second pipe ends having respective annular recesses (14, 13) therein defining, with the unthreaded bell section (9), an annular space (15) therebetween; a sealing sleeve within the annular space (15) having an outside diameter smaller than the inside diameter of the unthreaded section (9) of the bell (6) and being axially fixed in the recess (14) of the first pipe end.