Method and apparatus for coating the seams of welded tubes
US6290786A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1999 |
| Grant date | Sep 18, 2001 |
| Priority date | — |
| Expiry date | Jun 22, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2101/06
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The method for coating the seam of a welded tube of this invention includes applying a mixture of the desired protective metal coating in powdered form and a liquid flux over the internal surface of the welded seam with the welded seam located in a lower portion of the tube, then heating the welded seam to the melting temperature of the protective metal coating, melting the metal coating which flows over the seam forming an adherent metallurgical bond. The preferred apparatus includes a wand which extends between the opposed edges of the open seam tube in the welding apparatus and extends axially through the tube to overlie the welded seam spaced from the welding apparatus. The wand includes three conduits transmitting the powdered protective metal coating, liquid flux and nonoxidizing gas to the applicator which includes a nozzle which atomizes and sprays the liquid flux over the internal surface of the seam and which combines with the powdered protective metal coating to form a paste.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.