Patent · US Expired

Buttress thread form

US5092635A · kind A · utility

179Cited by
32References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 27, 1990
Grant dateMar 3, 1992
Priority date
Expiry dateApr 27, 2010

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16L15/001
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

The overall description of this invention is a truncated buttress-type thread form that incorporates a reverse-angle tension load flank with a compression flank and a torque shoulder; the thread does not have any radial interference designed into it, but the hooked tension flank does tend to pull the pin and box together once the torque shoulder is engaged. The mating compression flanks have designed into them a minimum amount of clearance prior to the shouldering action, which then closes to zero or very near zero at the moment the shoulder is engaged. This drawing together is due to the tendency of the hooked threads to pull together at shouldering if there exists no radial interference in the thread body. The thread roots and crests can be tapered, parallel to the taper of the thread body, or flat and parallel to the pipe axis but maintain adequate clearance to allow some closure once the shoulder is engaged so that the compression flanks can draw together.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.