Patent · US Expired

Butt-welding of pipes

US4957570A · kind A · utility

28Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 6, 1989
Grant dateSep 18, 1990
Priority date
Expiry dateJun 6, 2009

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T156/108
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The invention relates to the butt-welding of pipes of plastics materials. Equipment is alreaady known where pipe ends are first urged against a trimmer plate, and then urged against a heater plate to create beads of a required size at the ends of the pipes, following which the pipe ends are urged into abutting relationship for welding to occur. Particularly with automatic machines employing hydraulic power, the force applied between the pipe ends and the heater plate and subsequently between the pipe ends needs to include an allowance for the drag factor inherent in the pipeline and compensate for any frictional effect in the mechanical and hydraulic moving components, and which is a difficult calculation. The object of the invention is to overcome the difficulties mentioned above, which objective is met by means comprising two opposed clamping means in each of which is to be secured one end of a plastics pipe with the end of the pipe protruding beyond the respective clamp by a predetermined degree, said clamping means being movable towards and away from each other by the action of a suitable motive power, and there being linear movement sensing means to sense the degree of movemen…

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