Abstract: A new algorithm for extracting the torch high and low tracking deviation - the "adaptive substitution learning method" - is proposed based on the analysis and improvement of the welding current standard value setting method in the welding torch high and low tracking method. In addition, an adaptive variable domain fuzzy PID control method is designed, which introduces the variable domain into the fuzzy control to achieve adaptive tuning of the control parameters. The PID is then employed as the controller to achieve accurate output of the high and low deviation control amount of the welding torch. The experimental results demonstrate that the adaptive substitution learning method has a maximum extraction deviation of 0.24 mm, while the adaptive variable domain fuzzy PID control method has a maximum tracking error of 0.32 mm. These methods enable real-time and accurate control of the welding torch height in pipeline welding processes, satisfying the welding requirements of pipeline laying.