Compact large-penetration plasma arc welding gun

Abstract

The invention relates to a compact large-penetration plasma arc welding gun, and belongs to the technical field of plasma arc welding. The compact large-penetration plasma arc welding gun comprises atungsten electrode, a gas guide porcelain bushing, a water-cooling copper nozzle, a gas protective cover and a gas hood head which are sequentially arranged at the end part of the welding gun from inside to outside, ionic gas passes through the gas guide porcelain bushing and the water-cooling copper nozzle, and protective gas passes through the space among the water-cooling copper nozzle and thegas protective cover and the gas cover head; an insulating sleeve is arranged outside the tungsten electrode, a nozzle seat is arranged outside the insulating sleeve, the water-cooling copper nozzle is arranged at the end of the nozzle seat, the gas protective cover is arranged outside the nozzle seat, and the gas hood head is arranged at one end of the gas protective cover; and the water-coolingcopper nozzle is in a circular truncated cone shape, and the appearance inclination angle of the gas guide porcelain bushing is the same as that of the water-cooling copper nozzle. The nozzle is thickin upper portion, thin in lower portion, uniform in inclination and free of abrupt change structures, airflow can smoothly pass through the nozzle, the airflow is gradually compressed in the processof flowing along the inner wall of the nozzle, the higher speed is kept at the moment when ion gas flows out of the gun, and therefore higher penetrating power is achieved.

Description

technical field [0001] The invention relates to a compact plasma arc welding torch with large penetration depth, which belongs to the technical field of plasma arc welding. Background technique [0002] The development of welding technology with high efficiency, low energy consumption and high reliability is the development direction of advanced welding technology and the need of sustainable development of modern manufacturing industry. Due to the limitation of the penetration ability of the welding arc in the traditional arc welding process, for the connection of medium and thick-walled metal structural parts, the base metal often needs to be grooved on one or both sides for multi-pass multi-layer welding, which brings increased costs. , reduced production efficiency, expanded heat-affected zone, and welding defects. [0003] Plasma arc welding is an arc welding process with high energy density. It uses plasma arc as a heat source. After the welding arc undergoes thermal c...

AI Technical Summary

Problems solved by technology

However, when the thickness of the base metal is larger, the penetration ability of the arc is limited, and the stability of the piercing process is insufficient or the penetration cannot be achieved, which limits the application of plasma arc welding in the welding of large and thick plates.

[0004] In the welding process, in order to improve the welding quality and adjust the process parameters, it is necessary to monitor the state of the molten pool and the behavior of the arc. The cover usually includes a complex structure such as a water cooling system, which increases the diameter of the torch head, and in order to ensure the penetration and arc stiffness of the conventional welding torch, the height of the plasma arc welding is relatively small, generally controlled within 10mm, resulting in a poor view of the welding area. Narrow, which seriously affects the monitoring of the state of the molten pool and the arc behavior during the welding process

[0005] Conventional water-cooled gas hoods are directly in contact with ultra-high temperature arcs. Even if water cooling is used, it will still burn out in long-term use, and even destroy the water-cooled structure of the gas hood, resulting in unpredictable dangerous situations

[0006] To sum up, the existing plasma arc torches cannot meet the requirements of process improvement and quality improvement

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