Design And Experiment Of Large Penetration Tungsten Inert Gas Welding Torch

In this paper,a large penetration tungsten inert gas welding method(large penetration tungsten inert gas welding,LP-TIG for short)is developed for the conventional tungsten argon arc welding has some problems,such as low welding depth for single pass,low welding speed and low welding efficiency.The welding method is to strengthen the cooling tungsten and compress the arc to obtain a welding arc with high current density,high arc stiffness and strong penetrating power,realize perforation welding,increase welding penetration,improve welding efficiency of TIG welding,and expand the range of applications for conventional TIG welding.In this paper,the structure design of large penetration tungsten inert gas welding is carried out according to the principle of large penetration tungsten inert gas welding.The design of tungsten torch clamp,electric conductor,protective gas passage and water cooling passage are completed.Then the thermodynamics check of the water cooling effect and the numerical simulation of the gas protection are carried out for the design.The results show that the designed welding torch has good water cooling effect and gas protection effect,which can meet the design requirements and production requirements.In this paper,the suitability verification test for low carbon steel and stainless steel welding production is carried out for this welding torch.The results show that the welding torch can realize one-side welding with back formation process of 2mm-8mm thick low carbon steel and 6mm-10 mm thick stainless steel during butt welding,and the welding form is perforated welding,the welding process is stable,and the appearance of weld is better.In addition,the subject also carried out an adaptive verification test for stainless steel wire surfacing,groove backing welding and filling welding by the welding method.It can be seen from the test results that the maximum wire feeding speed can be up to 8 m/min when the method is used for surfacing.It is also suitable for backing welding in the range of 0mm-4mm blunt edge size.When used for filling welding,the filling speed of the wire can reach 8m/min.Therefore,it can be seen from the above test results that the large penetration tungsten inert gas welding method is a new type of high-efficiency TIG welding method,which will greatly improve the welding efficiency of TIG welding and expand the application range of TIG welding,which has broad application prospects.