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:
May. 24, 1983
Filed:
Apr. 25, 1980
Hans E Reusser, Westlake, OH (US);
Republic Steel Corporation, Cleveland, OH (US);
Abstract
A threaded joint for well casings and tubings includes a coupling or integral socket into which pipe sections are threaded. The coupling or socket includes an inner, unthreaded portion and an outer portion having threads on its inner surface. The pipe sections include an end having a threaded portion and an unthreaded nose portion at the outer end of the threaded portion. The nose portion terminates with an annular surface and includes a plurality of convex surfaces of revolution extending circumferentially of the nose portion, all of which surfaces are adapted to engage the unthreaded portion of the coupling or socket to establish a fluid-tight seal. The thread construction is a modified buttress type with relatively flat crests and roots. An interference fit occurs between thread portions not likely to be damaged during handling, and clearance between other thread portions permits the joint connection to be made with reduced friction and with reduced concern for machining tolerances. To increase effective wall thickness and overall strength of the joint, the threads are truncated to vanishing points. Hoop stresses are made low and relatively uniform throughout the entire range of tubing and casing diameters.