Device for detecting, during welding, variation in the physical state of the plastic material in a coupling piece of joining pipes
US5086213A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 1989 |
| Grant date | Feb 4, 1992 |
| Priority date | — |
| Expiry date | Dec 15, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C66/944
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention concerns a device for detecting variations in the physical state of the plastic material in a coupling piece used for welding pipes and incorporating a heating resistor, cavities which the softened material can enter and sensors for detecting the state of the material within the cavities. According to the invention, in order to obtain a weld of high quality, it is necessary for the distance between the bottom of the cavities and the part of the resistor nearest this bottom on the one hand, and for the linear dimension in the cross-section of these same cavities near their bottom on the other, to be less than or equal to the thickness of the material which is softened during the heating of the pieces. The invention applies to the control of the welding of sections of piping, particularly for the gas industry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.