It is well known that one of the key factors of welding quality is the configuration of welding power. At present, there are four kinds of power supply configuration or welding methods inside and outside the enclosure. In order to select the best, we made a comparative analysis.

（1）CO2氣體保護電源（熔化極）利用CO2氣體做保護。優點：CO2氣體低、生產效率高、焊接電流密度大、焊件基體熔池深、熔化效率高、熔敷速度快，生產效率比手工焊高2~4倍，而且抗銹、抗裂性能好；缺點：大電流焊接時，焊接表面成形較差、飛濺較多，焊后需人工除掉粘在工件上的飛濺物。

(1) CO2 gas protection power supply (melting pole) uses CO2 gas as protection. Advantages: low price of CO2 gas, high production efficiency, high welding current density, deep weld pool of weldment matrix, high melting efficiency, fast deposition speed, production efficiency 2 ~ 4 times higher than manual welding, and good rust and crack resistance; disadvantages: when high current welding, poor welding surface forming, more spatter, manual removal of spatter on the workpiece after welding.

（2）MIG氣體保護焊（熔化極），利用氬氣做保護。優點：焊接熔池深度大、焊接電弧穩定、焊縫成形好、生產效率高；缺點：因保護氣體用氬氣來實現焊接過程，氬氣偏高且MIG焊接電源較CO2/MAG焊接電源在上貴3~4倍。

(2) MIG gas shielded welding (metal electrode), using argon as protection. Advantages: large welding pool depth, stable welding arc, good weld formation and high production efficiency; disadvantages: because argon is used as shielding gas to realize the welding process, the price of argon is on the high side, and the price of MIG welding power source is 3-4 times higher than CO2 / MAG welding power source.

（3）MAG氣體保護焊電源（熔化極）。利用氬氣和CO2混合氣體保護，其中氬氣為80%、CO2為20%.優點：焊接熔池深度大、熔敷效率高、焊接飛濺較小，可獲得穩定的焊接過程和美觀的焊縫。

(3) MAG gas shielded welding power supply (metal electrode). Advantages: large weld pool depth, high deposition efficiency, small welding spatter, stable welding process and beautiful weld can be obtained.

（4） TIG氣體保護電源（非熔化極），利用氬氣做保護。優點：由于電極只通過電流加熱工件，使工件和焊絲形成熔池故沒有飛濺物產生，焊縫成形美觀；缺點：電弧熔池深度淺、熔敷率低、生產效率不高。因焊接過程全部采用氬氣做保護，偏高。

(4) TIG gas protection power supply (non melting electrode), using argon as protection. Advantages: because the electrode only heats the workpiece through the current, so that the workpiece and the welding wire form a molten pool, so there is no spatter, and the weld shape is beautiful; disadvantages: the depth of the arc molten pool is shallow, the deposition rate is low, and the production efficiency is not high. Because the welding process is all protected by argon, the price is on the high side.