The utility model discloses an one drags two types to draw arc formula stud welding machine, include: the box, horizontal direction both ends opening, by box body top cover, the both sides panel, boxbase constitutes, and a tailboard sets up in an open end upper portion, case panel sets up in another open end of box, sets up the ventilation mesh in the middle of the lower part, two welder do: twomanual welder, or an automatic welder leader moves welder, or two automatic welder, display panel, upper portion are equipped with adjusting button, an integrated MCU singlechip controller on the display panel, function control board sets up in the display panel opposite side, the ventilation pipe sets up in the base internal surface, the shielding housing is including horizontal backup pad, vertical supporting plates, the holding chamber encloses by shielding housing, both sides panel and base jointly, and vertical supporting plates has offered a supported hole, and the ventilation pipe is inserted and is located this supported hole. Stud welding machine inner structure carries out redesign, and the equipment of can effectively solving is inside because the high -intensity magnetic fieldcauses equipment frequently to damage the problem easily.