DIN 17456 stainless steel pipe welding method

　　DIN 17456 Stainless Steel Seamless Pipe are widely used in pipelines for pipeline transportation, such as oil, natural gas, water, gas, steam, etc. Stainless steel pipes are lighter in weight with the following characteristics: Same bending and shrinkage strength.

　　For steel pipes that are subject to fluid pressure and require thicker pipe walls, a hydrostatic test is required to verify their pressure resistance and that no leakage, wetting or expansion will occur under the specified pressure.

　　DIN 17456 Stainless Steel Seamless Pipe are taken as an example to introduce the horizontal fixation welding method.

　　1. Welding analysis: The horizontal fixed docking of DIN 17456 stainless steel seamless pipes is mainly used for nuclear power equipment and some chemical equipment that need to improve heat-resistant and acid-resistant pipes. In order to ensure safety and efficiency, the foundation is welded by TIG internal and external wire filling, and the filling layer and covering layer are welded by MAG welding, ensuring efficiency and efficiency. The thermal expansion rate and electrical conductivity of stainless steel are further increased than those of carbon steel and low alloy steel, and the molten pool fluidity and formability are poor, especially when welding in all positions. Stainless steel is generally only used for flat welding and flat fillet welding. During the MAG welding process, the extension length of the welding wire is less than 10mm, the swing amplitude, frequency, speed edge and dwell time of the welding gun are reasonably matched and the movements are coordinated. and overlays.

　　2. Welding method: The bottom of the DIN 17456 stainless steel seamless pipe is manually tungsten arc welded, mixed gas (CO2+Ar) shielded welding is filled and the cover is welded, and vertical and horizontal fixed all-position welding is used.

　　3. Preparation work before welding: A. Clean the oil stain and smooth it, and apply metallic glass to the groove surface and the surrounding 10mm. B. Check whether the water, electricity, and gas lines are smooth, and the equipment and accessories should be cleaned. C. According to the size, the positioning welding is fixed with ribs (2 o'clock, 7 o'clock, and 11 o'clock are fixed with ribs). In-groove tack welding can also be used, but attention should be paid to tack welding.