The elbow formed by steel hot pressing or forging process is stainless steel elbow. The stainless steel elbow is butt welded with steel pipe through elbow, and two workpieces are welded together along the whole end face through resistance heating. There are usually two methods of resistance butt welding and flash butt welding, with high productivity and easy automation, so they are widely used.
Stainless steel elbow not only saves space and reduces weight, but also ensures that the joint will not leak and has good sealing performance. Stainless steel elbow also has corrosion resistance (oxidizing acid, organic acid, cavitation), heat resistance and wear resistance. It is usually used in power station, chemical industry, petroleum industry and other industries. Stainless steel stamping elbow has poor weldability, so it should pay attention to the welding process The premise of heat treatment and the choice of suitable electrode.
Stainless steel elbows are widely used. They are rolled from ordinary carbon structural steel, low alloy structural steel or alloy structural steel. They are mainly used as pipes or structural parts for conveying fluid. When ball valves, globe valves and gate valves with stainless steel elbows are used, they are not allowed to be used for flow regulation, but can only be fully opened or closed, In order to avoid corrosion and accelerated wear of the sealing surface, reverse sealing device is set inside the gate valve and threaded stop valve, and the hand wheel is rotated to the upper position and tightened to prevent medium leakage from the packing.
Most stainless steel elbow fittings are used for welding. In order to improve the welding quality, there are grooves with certain angle and edge at both ends. This requirement is also very strict. The thickness, angle and deviation range of the edge are specified. The geometric size is much more than that of the pipe fittings. The surface quality and mechanical properties of the elbow are basically the same as those of the pipe. In order to facilitate welding, the steel of the pipe to be connected should be the same, In addition to a few hydrogenation agents, stainless steel elbow can also resist the corrosion of various chemical media, with excellent acid resistance, alkali resistance, corrosion resistance, no rust, no corrosion, no bacteria breeding, no electrochemical corrosion.
