The manufacturing process of the elbow 90 is: use an iron plate to heat it to the heating point, and then send it to the press mold. Under normal conditions, it is enough to press three times, and then put the blank on the cutting disc, and cut the rest. Then let the AB surface contact.
butt, and then use electric welding to continue, and then flatten the elbow mouth with a lathe. Under normal circumstances, it is made like this. Sometimes the butt welded elbow has a weld, and it is welded. After the completion of the construction operation, it is necessary to perform anti-rust or anti-corrosion treatment according to the actual conditions or the external environment of the pipeline to prevent the elbow from rusting or corroding at the weld.