Valve weld Skill improved: fish scale weld,TIG( Tungsten invert gas welding)

Welding Skill is very important for Some valve manufacture. Sangong’s pursuit of improving welding technology never stops. Last weekend, the Sangong welder have an deep communication with other skilled welder engineer after attend an welder exam local.

High pressure Power Plant valve fish scale weld-TIG

For the fish scale weld showed in competition,also named TIG( Tungsten invert gas welding), is a kind of welding technology.  It is named for its scale-like welding plane. Its characteristic is that the pipe is directly welded to the pipe. The main thing is to select the welding point, electrify, knock out the arc with the welding rod head, melt the flux in the welding rod, and then swing the welding clamp to make the welding center melt evenly in the welding position. Should be because the general welding effect is good, it will be like fish scale, so called fish scale welding in china.

Sangong welders exchanged welding skills with each other:

1. TIG welding itself belongs to open-arc operation. It can observe the shape and flow of molten pool very well, which is much superior to electrode arc welding.

2. Controlling the hand stability during welding is the key to avoid shivering and burning the dock pole causing tungsten inclusion in the molten pool. The control method can use the index finger of the welding torch to support the welded pipe or plate. Tungsten pole extension length can be selected according to the depth of groove, generally 3 ~ 5MM.

3. The wire transport method can be selected according to the size of the groove. When the groove angle is small, the welding wire can be placed in the middle of the solution pool and continuously fed into it. When the groove is large, two side points can be used to feed the wire (to be quite skilled, avoid touching the dock pole). The welding torch moves left and right to make the edge fuse well.

4. On the surface of the full scale, according to the scoring standard of the test competition, the residual height of TIG weld is generally 0-2MM, and the surface is smooth without undercut, blowhole, crack and fusion.

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