Manual welding features-small tube horizontal fixed welding

Release time:

2023-08-01

Its welding characteristic is that the weld formed on the back of the root welding is oxidized in contact with the air, resulting in no texture on the surface of the weld and a flowering shape. Therefore, hydrogen charging protection is carried out on the welded pipe during welding to prevent oxidation.

Its welding characteristic is that the welding seam formed on the back of the root welding is oxidized in contact with air, resulting in no texture on the surface of the welding seam and a flowering shape. Therefore, hydrogen charging protection is carried out on the welding pipe during welding to prevent oxidation. After the weld pool is formed during the welding of the root of the

weldment, under the action of the shielding gas in the weldment tube, a small amount of opposite thrust or rising force will be generated from the liquid metal of the weld pool to the back of the weld. Therefore, when the temperature of the weld pool is too high, the surface tension of the weld pool is small, which will cause the bottom half of the weld to produce concave on the back. When the temperature of the weld pool is low, the surface tension of the weld pool is large, which will encourage the root of the weld to be opaque, and there is also a concave. According to the welding characteristics of the weld, the hydrogen flow rate in the input weldment pipe is adjusted before welding, so that the hydrogen flow rate filled into the weldment pipe can protect the molten pool and isolate the air. Excessive use of hydrogen flow rate is also a waste. The pipe diameter of

weldment is small, and the gap of weldment shrinks quickly during welding, so the welder is required to master the welding technology. The welding speed at the root of the weldment should be fast, from the start of welding to the end of welding, it should be formed in one breath to prevent the shrinkage of the weld gap and avoid the scrapping of the weldment due to excessive shrinkage of the weld.

filling and cover surface welding due to the small pipe diameter of the weldment and the dripping of the pipe wall, the weldment will be cold and hot during welding. At the same time, the small heat of the pipe cannot be dissipated, resulting in the higher the temperature during welding, resulting in overheating of the formed weld seam, and the root seam will be welded through during filling and welding. If overheating occurs in the flat welding position, the surface of the weld seam will produce weld bumps; if overheating occurs in other welding positions, the back of the weld seam will produce concave. According to such welding characteristics, the welding speed of the weldment should be fast to reduce the heat input to the weldment and prevent the temperature of the weld from being too high. After the first half of the weld is welded, the weldment can be stopped, and the second half of the weld can be welded after the temperature of the weldment drops. The above overheating problem can be avoided by this method.

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What welding rod is used for welding cast iron and ordinary steel plate

None

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