Patent · US Expired

Measurement of pipe joint misalignment at weld interface

US6273320A · kind A · utility

10Cited by
15References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 21, 2000
Grant dateAug 14, 2001
Priority date
Expiry dateAug 21, 2020

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K2101/06
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

A method of monitoring the alignment of pipes to be welded end to end involves supporting a reference bar extending generally parallel to, and external of, the pipes so as to span a weld position of which the ends of two pipes are to be welded, performing measurements of perpendicular distance between the bar and each pipe at two predetermined distances from the end of each pipe, determining the thickness of the walls of the pipes, determining the slope of the exterior of each pipe with respect to the reference bar, calculating from the slopes the difference between the distances from the bar to the outer surface of each of the two pipes to the weld position, so as to provide a measure of the misalignment of the outer surface of the pipes at the weld position, differencing the wall thicknesses of the pipes to provide a wall thickness difference, and subtracting the wall thickness difference from the misalignment of the external walls of the pipe to determine the misalignment of the inner surfaces of the pipes at the weld position. It is preferred to measure pipe thicknesses at multiple distances from the end of each pipe and average the results to obtain average thicknesses for the…

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