Precautions for welding technology of stainless steel butt welding elbow?

Before welding, the butt welding elbows are welded with stainless steel arc plates and keels to align the outermost tiles on both sides of the whole elbow to avoid welding deformation. The method requires argon filling welding. Considering the welding cost and the large diameter of the shrimp waist tube, it is difficult to fill argon. Summarizing the above factors, two welders inside and outside are used to weld together symmetrically, which solves the problem of argon filling , And the shape is also very good.

The welding process of argon spot joint welding is selected. The electrode is A022 and the welding wire is selected: HOOCr21Nil0. The lower layer is selected by argon arc welding. Before the electric welding operation, brush the stone chalk powder within 100mm on the left and right sides of the welding seam to avoid spattering and adhering to the surface of the pipeline. Before performing the electric welding operation, select a small current. Multi-layer and multi-pass, continuous welding. After the entire welding is completed, the weld points and spatters on the surface of the butt weld elbow are polished, and the pre-welded tile is finished.

Carry out non-destructive testing, pickling and passivating the outer and inner welds. Transport the elbows after pickling to the installation site for on-site installation work. Butt-weld elbow is an elbow that is formed by hot press forming of steel or by forging technology. The connection method is butt welding of the elbow and the steel pipe, and the two workpieces are welded together along the entire end surface by resistance heat, usually with resistance Two methods, butt welding and flash butt welding, have high productivity and are easy to automate, so they have been widely used.

Stainless steel butt-welded elbows not only save space and reduce weight, but more importantly, they ensure that joints will not leak and have good sealing performance. The size of the compact flange is reduced because the diameter of the seal is reduced, which will reduce the cross section of the sealing surface. Secondly, the flange gasket has been replaced by a sealing ring to ensure that the sealing face matches the sealing face. The B value of the 45-degree elbow is the structural scale, which is mainly to bring convenience to pipeline planners.