The invention provides a method for 
welding an anticorrosion 
steel pipeline with no internal repaired mouth, which is applicable to the anticorrosion treatment of a 
steel pipeline welding connector with an anticorrosion 
coating in the 
petroleum industry and the 
chemical industry. The method is characterized in that a groove with a certain length and depth is machined on a position which is at a certain distance from the end part of the steel 
pipe, an anticorrosion 
alloy material is surfaced on the groove, the end part of the surfaced steel 
pipe is machined into a V-shaped groove, an anticorrosion 
coating with sufficient thickness is coated on the inner wall of the steel 
pipe, the anticorrosion 
coating covers sufficient length of the anticorrosion 
alloy surfacing layer, then two steel pipes are in butt connection with each other, layering 
welding is carried out after the two steel pipes are fixed on one point, an 
argon tungsten-
arc welding method is adopted, the anticorrosion 
alloy material which is identical to that of the surfacing is selected as the filling material, and 
argon is filled into the pipe to protect the pipe in the 
welding process. Due to the adoption of the novel technology for welding the anticorrosion 
steel pipeline with no internal repaired mouth, the 
corrosion resistance of the inner wall and a weld mouth of the pipeline can be guaranteed, the 
internal mouth repairing technology on the spot after the welding can be avoided, characteristics such as simplicity in construction and reliability in performance can be realized, and the method is suitable for the real 
engineering application of the 
petroleum and 
chemical industry fields.