摘要 |
FIELD: welding processes and equipment, possibly in different branches of national economy, namely semiautomatic and automatic gas-shield welding by means of consumable electrode. ^ SUBSTANCE: method comprises steps of assembling parts of structure by means of tack welding; preheating part butts by means of autonomous-power electric arc excited between non-consumable electrode and structure; then welding parts. Zone of starting seam to be welded next or end zone of non-finished seam along butt of parts is subjected to preheating till formation of welding bath. After achieving desired heating degree voltage is switched to consumable electrode and welding is performed. After tack weld appears in welding zone voltage is again switched to non-consumable electrode for guaranteed fusion of it. When tack weld is fused welding process is going on by means of consumable electrode. Preheating and gas-shield welding are realized with use of non-consumable electrode. ^ EFFECT: increased density of welded joint at initial time moment of welding, possibility for performing welded seams of predetermined geometry. ^ 2 cl, 2 ex |