Method for defect free keyhole plasma arc welding
US5225654A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 1992 |
| Grant date | Jul 6, 1993 |
| Priority date | — |
| Expiry date | Jul 15, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K10/02
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A plasma arc welding process for welding metal of increased thickness with one pass includes operating the plasma arc welding apparatus at a selected plasma gas flow rate, travel speed and arc current, to form a weld having a penetration ratio to weld height to weld width, and maintaining the penetration ratio at less than 0.74. Parameters for the plasma gas flow rate, travel speed and arc current are adjusted to a steady state condition during a start up period and maintained during the steady state condition to complete a weld. During a terminal stopping period, the travel speed is stopped and instantaneously replaced by filler wire which adds material to fill the keyhole that had been formed by the welding process. Parameters are subsequently adjusted during the stopping period to terminate the weld in a sound manner.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.