Patent · US Expired

Method and apparatus for controlling root pass weld penetration in open butt joints

US4733051A · kind A · utility

48Cited by
9References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 25, 1987
Grant dateMar 22, 1988
Priority date
Expiry dateAug 25, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB23K9/0956
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The invention is concerned with controlling weldpool penetration during root pass welding in an open butt joint defined in a workpiece to be welded by a welding torch with a welding wire being continuously fed from the welding torch to the joint to form a weldpool penetrating the joint, the workpiece and welding torch being movable relative to one another. A visual sensor is positioned ahead of the welding torch and in alignment with the joint for frontly viewing the weldpool at an angle of about 10.degree. to about 20.degree. relative to a line tangent to the workpiece at the weldpool, to thereby provide a full image of the weldpool defining a weldpool contour line, the sensor and welding torch being disposed on a common side relative to the workpiece. The weldpool image is then processed through a computer including image processor operatively coupled to controller, the image processor analyzing the weldpool contour line to derive therefrom weldpool penetration depth and comparing the weldpool penetration depth with a predetermined value, to thereby provide an information signal representative of weldpool penetration error which is fed to the controller, the controller issuing co…

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