The stainless steel lining technology began to be used in the mid-1960s. The thin wall stainless steel pipe is used as the carrier, after welding and forming, the stainless steel lining pipe is pulled from one end of the pipe to be repaired to the other end with the traction winch as the power. After the stainless steel pipe liner is inserted, it shall be punched, and the gap between the liner and the original pipeline shall be grouted and solidified under the condition of pressure maintaining. The composite pipe with smooth surface and tight adhesion with the original pipe is formed. So as to achieve the repair purpose of strong pressure bearing, impact resistance and overall corrosion resistance, and extend the service life of the original pipeline for more than 50 years. Lined stainless steel elbow includes an outer pipe and a stainless steel inner pipe. The joint between the outer pipe and the stainless steel inner pipe of the product is provided with a stainless steel sealing device. The stainless steel sealing device of the product is welded to the outer pipe and the stainless steel inner pipe. Two cross set stainless steel support pipes are welded to the stainless steel inner pipe of the product. This product effectively extends the service life of the stainless steel elbow. The setting of the stainless steel support pipe can improve the overall strength of the stainless steel elbow, improve the compression resistance and anti-collision performance of the stainless steel elbow, and make the stainless steel elbow more widely applicable. Lined stainless steel elbow pipe fittings include galvanized elbow outer pipe and stainless steel inner lining pipe. The stainless steel inner lining pipe is provided with a flanging which is close to the interface end face of the outer pipe of the galvanized elbow; Concrete is filled between the stainless steel inner liner pipe at the flanging and the galvanized elbow outer pipe. The utility model can increase the service life of the elbow and prevent the inner wall of the outer tube of the elbow from being corroded.