How to operate the vertical fixed welding of the riding tube sheet?

Ride-on tube sheet welding requires root penetration and requires good backside forming, so the operation is difficult. According to different spatial positions, riding tube sheet welding can be divided into three types: vertical fixed fillet welding, vertical fixed elevation fillet welding and horizontal fixed welding. Today, I will talk with you about the vertical fixed welding of the riding tube sheet. Tack welding is usually welded by the intermittent wire filling method. The length and number of tack welds are determined according to the diameter of the pipe, generally 2 to 4 sections, and each section is 10 to 20 mm long. When bottoming welding, first start the arc on the tack weld, swing the arc in situ, wait for the tack weld to melt to form a stable molten pool, and then fill the wire and weld to the left to ensure the backside is well formed. During the welding process, the molten pool should be observed at any time, and the angle between the welding torch and the bottom plate should be properly adjusted to ensure the consistent size of the molten hole and prevent burn-through. When welding to other tack welds, the wire feed should be stopped or reduced to melt the tack weld and make a smooth transition with the previous bottom weld. When the arc is extinguished, press the switch, the current begins to decay, stop the wire feeding after filling the arc crater, and the molten pool solidifies after the arc is extinguished. When making a joint, start the arc at a position of 10-15mm behind the arc crater, and move the arc to the joint at a slightly faster speed; after the original arc crater is melted to form a molten pool, the wire is filled and welded normally. If there are local protrusions on the bottoming weld bead, use an angle grinder to smooth it out and then perform cover welding. When filling welding or cover welding, the swing of the welding torch is slightly larger, so that the groove edges of the pipe and the plate are fully melted, the filling welding seam should not be too wide or too high, and the surface should be flat. Cover welding sometimes requires two passes, the bottom one should be welded first, and the top one should be welded last. When welding the bead below, the arc swings around the lower edge of the bottoming bead, the upper edge of the molten pool is controlled at 1/2 to 2/3 of the bottoming bead, and the bottom edge of the molten pool is controlled at the slope. 0.5-1.5mm below the lower edge of the mouth. When welding the upper bead, the arc should swing with the upper edge of the bottoming bead as the center, so that the upper edge of the molten pool exceeds the upper edge of the groove by 0.5-1.5mm, and the lower edge of the molten pool and the lower bead smoothly transition to ensure the welding seam. The surface is smooth and even.铜焊丝,Copper Welding Rods,铝焊丝,aluminium welding wire,镍焊条,Nickel electrode,药皮焊条,Flux Coated Brazing Welding Rods