Welding method of fire-fighting pressure reduction pump

The invention discloses a welding method of a fire-fighting pressure reduction pump. The method is characterized by comprising the following steps: firstly, before welding, the welding position must be cleaned up, the welding metal at the original cracking portion is taken away, polishing through an alternating phase polishing machine or carbon arc air gouging is used, and after the cracking portion is gouged, ferric oxide must be cleaned up through polishing; secondly, before welding, preheating is carried out, preheating is carried out on the welding position, intermittent welding, dispersed welding or after-welding hammering is adopted, a hammer is used for knocking the welding line and the welding line edge, and after complete welding, the hammer is used for knocking until the welding line is cooled; and thirdly, it is ensured that the fire-fighting pressure reduction pump and a fixed pipeline welding must be thoroughly welded, and a back plate is additionally arranged on the outer side of the pipeline. 本