Strict control layer between temperature layer 100 of 150 ° C temperature control.
Manual arc Welding Electrode welding operation technology: backing weld special attention to the size and shape of the control of the molten pool, pool size should be controlled in of 5 ~~ 6mm oval shape, shipped Article uniform line; weld surface should be as smooth as possible easy slag, to reduce the amount of convex weld grinding, and better control of the lower welding intermittent, reduce the generation of defects in welds; weld the joints before closing arc should be polished into a gentle slope like at the joints The front-end to ignite arc, pull back to normal welding joints, to avoid the production of welded joints pores and slag.
Argon-enriched welding operation techniques: rich argon welding, to pay special attention to the control of the arc voltage and the welding speed the key is to maintain the arc length during the welding process does not change the basic. Dry elongation of 10 ~ 15mm, gases argon and carbon dioxide gas mixture left welding welding, welding power DCRP.
Control of the welding parameters: welding should be strict control of process parameters is not allowed to exceed the specified range.
After heat treatment: after heat treatment to eliminate the the weld residual hydrogen and residual stress, improve weld microstructure and mechanical properties, is one of the effective measures to prevent cracks. After the heat treatment process: flame heating the weld on both sides of 100mm, the heating temperature to 300 to 350 ℃, asbestos insulation, asbestos thickness of 100mm, width of 400mm, holding time 2h freedom cooling.
Welding procedure(Welding Electrode Manufacturer) qualification results
Specimens in accordance with the completion of welding procedure qualification JB/T4730-2005 standard X-ray flaw detection after 24 hours by the third-party testing company found no defects exceeding the weld quality meet the design requirements weld grade grade II or more, detect weld mechanical properties to meet the design requirements.