| 219 / | HD | ELECTRIC HEATING |
|
| 50 | DF | METAL HEATING (E.G., RESISTANCE HEATING) {19} |
| 121.11 |  | .~ By arc {16} |
| 121.12 | DF | .~.~> Using electron beam {12} |
| 121.36 | DF | .~.~> Using plasma {8} |
| 121.6 | DF | .~.~> Using laser {12} |
| 122 | DF | .~.~> Control of arc direction {1} |
| 124.01 | DF | .~.~> With ignition by retraction |
| 124.02 | DF | .~.~> With gap control {1} |
| 124.1 | DF | .~.~> With automatic positioning of arc {4} |
| 125.1 | DF | .~.~> With predetermined welding operation {3} |
| 127 | DF | .~.~> Spot arc bonding (e.g., arc riveting) |
| 128 | DF | .~.~> With working of bonding metal (e.g., by peening) |
| 129 | DF | .~.~> Brazzing or soldering |
| 130.01 | DF | .~.~> Including circuits for monitoring arc parameters |
| 130.1 | DF | .~.~> Including arc-power supplies {5} |
| 136 | DF | .~.~> Welding {1} |
| 137.2 | DF | .~.~> With consumable electrode device {4} |
| 138 | DF | .~.~> Electrode holder (e.g., spring biased tong) {4} |