Method for tube welding
US4142085A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1977 |
| Grant date | Feb 27, 1979 |
| Priority date | — |
| Expiry date | Jan 27, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K33/004
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for butt welding a pair of vertically disposed tubular members having a wall thickness of more than 12 mm in end-to-end relationship by multi-pass shielded arc welding with a consumable electrode, comprising the steps of preparing the opposed edges of the tubular members by forming a root face the width of which being in the range of 0.5 mm to 3.0 mm and beveling the edges adjacent to the root face to a bevel angle in the range of 40.degree. to 50.degree., coaxially aligning said tubular members so that the gap between the root faces is not larger than 1.5 mm, performing a root pass by continuously feeding an electrode having a diameter not larger than about 1.0 mm into the groove between the prepared edges supplying a shielding gas consisting of 0-40% carbon dioxide and the balance argon, energizing an arc between the electrode and the root face alternately changing the voltage supplied to the arc between a low value and a high value, adjusting the low voltage to produce a droplet metal transfer during short circuit periods, adjusting the high voltage to produce a spray metal transfer, adjusting the welding speed and the electrode feeding speed to deposit metal in the gro…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.