When the front wire current of spiral seam welded steel pipes is generally less than 1000A, the back wire current is about 380A-420A, and the voltage is about 33V-37V. When the current of the front wire of the spiral seam welded steel pipe is greater than 1000A, the current of the back wire is about 420A-500A, and the voltage remains basically unchanged. According to experience, an increase of 0.1m/min in welding speed results in a 50-60A increase in front wire current