The characteristics and scope of application of submerged arc welding

Submerged arc welding is a welding method using the arc as the heat source. During submerged arc welding, the arc burns under the fusible flux, the arc is not exposed, and the metal electrode used is the continuous feeding smooth welding wire.

Submerged arc welding is divided into automatic submerged arc welding and semi-automatic submerged arc welding. During welding, the flux diffuses to the front of the arc through the funnel. After welding, the unmelted flux can be recovered automatically by the flux recovery device or cleaned manually.

Advantages and disadvantages of submerged arc welding

Advantages of submerged arc welding

1.The welding current used is large, the corresponding input power is large, coupled with the heat insulation effect of flux and slag, the thermal efficiency is high, the melting depth is large, the groove of the workpiece is small, and the amount of metal is reduced. The single wire submerged arc welding can penetrate 20mm without groove.

2.The welding speed is fast. Taking the steel plate with thickness of 8 ~ 10mm as an example, the submerged arc welding speed can reach 50 ~ 80 cm / min.

3.The existence of flux can not only separate the contact between molten metal and air, but also slow down the solidification of molten pool metal. Liquid metal and molten flux have more time for metallurgical reaction, reducing defects such as pores and cracks. Flux can supplement alloy elements to weld metal and improve weld mechanical properties

4.During automatic welding, the welding parameters can be adjusted automatically. Compared with manual arc welding, the dependence of welding quality on the welder's skill level is reduced.

Disadvantages of submerged arc welding

1.Due to the use of granular flux, this welding method is generally only applicable to the flat welding position. Special measures shall be taken for welding at other positions to ensure that the flux can cover the welding area.

2.The relative position between the arc and the groove cannot be observed directly. If the automatic weld tracking device is not used, the welding deviation is easy to occur.

3.When the electric field intensity of submerged arc welding is large and the current is less than 100A, the arc is unstable.

Scope of application of submerged arc welding

Due to its large penetration and high mechanization, submerged arc welding is suitable for long weld welding of medium and heavy plate structure. It is one of the most commonly used welding methods in welding production.