Submerged arc welding steel tube how to ensure and improve the welding quality

In advance before the end of the welding steel pipe (1) the edge milling welding arc plate (2) to find the same arc plate and the thickness of the parent metal, arc plate to choose the width of the edge milling machine roller rolling to (the edge milling machine roll and knife plate distance, not too narrow, later to the horizontal push) (3) the method of welding arc plate: will first arc plate processing a single groove. Available band saw, sawing (4) and then welded steel pipe for the welding arc plate into the end of the steel plate (front-end preweld) card will red copper plate with a bow or brick, ceramic pads, etc. Using reinforcement plate to reserve first bending. (5) with carbon dioxide gas shielded welding is firm. Welding arc plate must be in front of the milling process, (6) at the beginning of the pre welding pipe end manual welding, the request as short as possible (should be kept within 2 cm, otherwise easy to have flash), used to prevent steel tube cracking: not allow meter long pass, long welding should be close to with automatic welding. (7) the pipe welding can be on the arc board, to prevent the steel pipe cracking, such as arc plate opening is too big, can use a special tool to eliminate before welding. (8) steel pipe welding is completed, with a burning torch in pipe end cut qi, monolithic shed welding arc plate mouth, again and weld, prevent gas while the internal and external welding plane, excluding the manual weld steel pipe cracking. (9) CO2 gas shielded welding wire by hand should choose the filament diameter 0.8 1.2 mm, not with diameter of 1.6 mm wire first. The quality of the welding arc plate directly affect the weld quality of steel pipe. Thick wall welding (10), the car should need to adjust the horizontal Angle, thick wall welding should choose uphill welding or horizontal welding, welding wire to pour. (11) thin-wall welding, horizontal Angle should be chosen car downhill welding wire to forward, but also need to see the weld shape appearance and inner quality, (12) wire elongation, double wire welding is 6-8 degrees, the diameter is 8 to 10 times the diameter of the monofilament welding.

Arc plate in submerged arc welding steel pipe welding technology has prominent effect, effectively guarantee the quality of the submerged arc welding seam qualification rate. Good up welding work is important to the success of a submerged arc welding process.