Patent · US Expired

Method and apparatus for ensuring correct thread make-up of a pipejoint

US4515020A · kind A · utility

2Cited by
7References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 23, 1983
Grant dateMay 7, 1985
Priority date
Expiry dateFeb 23, 2003

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB25B23/14
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method and device for ensuring correct assembly of screwed pipejoints having at least one stop. During assembly the screwing torque is measured continuously, the value of the second differential of the screwing torque is determined uninterruptedly, and the maximum of this second differential is checked to exceed a predetermined value. The device includes in combination: a means of converting into electric voltage the value of the tightening torque applied at every instant during the assembly of the joint, an electronic device for carrying out the calculation of the second differential of the curve of electric voltage so measured, and a device enabling the value of this second differential to be compared with a reference value for giving a signal when the maximum of the second differential exceeds or does not exceed the reference value.

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