| 摘要 |
<p>1,101,036. Welding by fusion. SOC. ANON. DES ATELIERS DE SECHERON. 11 May, 1965 [11 May, 1964], No. 19867/85. Heading B3R. [Also in Division H2] In constricted arc welding metal sheets of thickness less than 0À5 mm., the current is such that the arc beyond the constriction would normally be unstable, and the arc is stabilized by confining substantially the whole of the arc beyond the constriction by a shielding gas atmosphere substantially not ionizable by the arc effluent issuing from the constriction. The current range is from a few hundred milliamps to 5 amps. The gas forming the arc effluent is inert, e.g. argon, and the gas shield is a dissociable gas, e.g. hydrogen, nitrogen or carbon dioxide, or a mixture thereof with argon or helium. The welding torch has a detachable constricting nozzle 2, an outer gas nozzle 22 and a non-consumable electrode 1. During operation a pilot arc initiated between the nozzle 2 and the electrode 1 by a brief h.f. discharge is maintained continuously so that the main arc to the work strikes as soon as the torch is near the work.</p> |
