Abstract: Objective To solve the problems such as large deviation of welding joints, cumbersome robot programming and difficult forming of automatic welding. Methods Firstly, the low-load six-axis argon arc welding industrial robot was used as the main body, equipped with laser vision sensor, molten pool vision sensor, main control computer and other peripheral advanced equipment, and the argon arc welding robot workstation was built.Secondly, the off line programming welding system based on model driven was developed.The control principle and establishment mode of the key modules of the system were analyzed.Finally, taking the carbon steel petrochemical pipe fittings with prefabricated horizontal rotating welding joints as an example, the adaptive intelligent welding process test of argon arc welding robot was carried out within the specified range of assembly gap and misalignment, the mechanical properties and microstructure of the weldments were tested. Results When the assembly gap was controlled within 0～2.50 mm and the misalignment was controlled within 0～2.0 mm, the adaptive intelligent welding process test of the argon arc welding robot for petrochemical pipe fittings was completed in the model-driven off-line programming welding control system by using the welding process database, laser vision tracking and pass planning modules. The mechanical properties and microstructure of welded specimens met the standard requirements. Conclusion An adaptive intelligent welding technology for rotating welding nozzle argon arc welding robot was developed, which solved the problems of difficult automatic welding base forming and cumbersome robot programming for petrochemical pipe fittings. It provided technical reference for the high-efficiency and intelligent welding landing application of non-standard petrochemical pipe fittings in the industry.