Valve core suspension welding and positioning device for EGR valve

The invention discloses a valve core suspension welding and positioning device for an EGR valve. A welding through hole is formed in the middle of a valve body placing base, the outer diameter of the lower end of the valve body placing base is matched with a hole of the valve body, an annular groove is formed in the lower end of the valve placing base, a piston ring is installed in the groove, an O-ring seal ring is arranged between the piston ring and the side wall of the groove, the piston ring is communicated with an air inlet, and a return spring is arranged at the lower end of the piston ring; a movable expanding block is located between the outer side of the piston ring and the inner wall of the hole of the valve body, and the piston ring is inflated to drive the movable expanding block to move toward the inner wall of the hole of the valve body; the return spring is fixed to the valve body placing base through a fixing nut, a valve core is installed between the lower end face of the valve body placing