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. 12, 1978
Filed:
Sep. 20, 1977
Eishiro Miida, Tokyo, JP;
Tsukamoto Seiki Co., Ltd., Tokyo, JP;
Abstract
Pipe joints for a large diameter casing, which are lowered inside an oil well or the like and are successively connected to one another, are subjected to critical conditions such as load on the casing when suspended, and pressure. A pipe joint of this class is also required to provide torque during the connecting operation and sealing capability after connection. Tooth profiles or thread configurations formed in the pipe joints welded to the intervening large diameter tubular member extend over at least three sections. In the first section, each of the external threads is engaged with each of the internal threads in such a manner that its crest and root are fully meshed to allow its butt face to abut against its back pressure face. In the second section adjacent the first section, the threads are so formed as to involve an easy transition to the thread configuration formed in the third section where the threads are so shaped that the external threads are readily meshed with the internal threads. Threaded in this manner, a pipe joint can be obtained that satisfies operative characteristics such as pressure tightness, sealing capability, and workability.