ONE-SIDED WELDING USING "HOT START"
One-side manual welding of root-runs, against ceramic backing and using "hot-start" devices, allows the use of relatively high currents close to the maximum capacity of the electrode because it prevents burning-through and shapes the root-side underbead smoothly. De-gassing of the weld metal is therefore easily finished before the metal solidifies. The ceramic backing and the use of the over-current (a pulse of about 100A above the chosen welding-current) when restriking make it possible to burn through a remelt defects such as pipe and cracks. The operator controls the over-current by means of a switch on the electrode holder. A case study is presented in which one-side welding, for 20-mm plate welded on site in the horizontal position, is shown to result in a saving of about 20 to 35% in operating time and costs as compared with a traditional method; this result is discussed. Some recommendations are included on the choice of equipment for hot-start welding.
- This article first appeared in the ESAB publication "Svetsaran."
IPC Science and Technology Press LimitedIPC House, 32 High Street
Guildford, Surrey England
- Publication Date: 1977
- Pagination: 2 p.
- Welding and Metal Fabrication
- Volume: 45
- Publisher: Engineering, Chemical and Marine Press, Limited
- TRT Terms: Electrodes; Welding
- Old TRIS Terms: Hot start welding; One side welding; Welding electrodes; Welding techniques
- Subject Areas: Construction; Marine Transportation;
- Accession Number: 00158013
- Record Type: Publication
- Source Agency: British Ship Research Association
- Files: TRIS
- Created Date: Aug 31 1977 12:00AM