Research On The Welding Technics And The Welding Equipments During The Multiple Sources Stud Welding By Robot

In this paper, in the view of the middle carbon steels in high strength and high hard conditioning with large diameter studs welding application, research use induction heating/arc stud welding this kind of method, and carried out the research work of the compound heat sources welding technology, welding parameters, the mechanical prorerty of the welding joints, microstructure of welding bead, sufficient optimize this welding method, gave out the optimum parameters of standard window in the actual welding conditions, and ensure the strength of welding joints is more than 0.95.As the same time to meet modern industrial production efficiency, automation, intelligent development trend, research and design the equipment of automatic feed, welding torch change, ceramic ring clamping no matter what kinds of diameters of the studs and the welding positons, program and realize the composite heat sources studs welding efficient automatic welding.For large diameter studs welding, traditional methods are manual arc welding or semi-automatic gas shielded welding, such kinds of methods are strict to welding request and the efficiency is low, to meet modern industrial production efficiency, automation, intelligent development trend, research and design the equipment of automatic feed, welding torch change, ceramic ring clamping no matter what kinds of diameters of the studs and the welding positons, program and realize the composite heat sources studs welding efficient automatic welding.In traditional body interior surface of tanks, there are a lot of large diameter studs welding by manual arc welding or semi-automatic gas shielded welding methods, appear incomplete fusion, porosity, mingled, etc welding defects. Research using induction heating/arc stud welding methods, and carry out the welding research of the 16,22,27mm diameter studs and 30,45,80mm thickness of high carbon steel, tests show that:in proper welding process specification window, the welding process stability, form perfect external circular convex platform that can strength the welding joints, the strength coefficient of welding joints is more than 0.95. The microstructure of welding bead shows that the front of the stud and the surface of the high carbon steel are heated and melt even, and do not find incomplete, porosity, crack,etc welding defects, the microstructure of welding bead is martensite and bainite, welding heat affected zone of high carbon steel side do not find crack. In the view of the actual welding conditions of existence asymmetric structure and high restrain of large diameter studs welding with high carbon steels, the welding bead always appears the phenomenon of delay crack. Research carried out the work of delay crack simulation test, welding process test, welding joint residual stress analysis, welding bead organization of hydrogen amount, etc, the analysis shows that the high carbon steel in hard condition, the high carbon equivalent, high hardened tendency, the hydrogen quantity of welding bead, the restrain of the welding joint are the most important elements of the phenomenon of delay crack.Using the method of induction heating/arc sutd welding can effectively reduce the residual stress of welding joint, the amount of hydrogen of welding bead, and test sample do not appear the phenomenon of delay crack.