
The middle of 1990s, a number of published works in mathematical calculations based on the establishment of a high-frequency welding theory, mathematical theory most representative: speculation is accurate welding speed and welding power according to the length of the V-shaped region, plates and welding frequency relationship. This theory tube welding has been successfully used for several years, has been in Ma Tours company for performance evaluation of welding equipment, the theory accurately speculate over a wide range of different specifications of steel pipe welding power and welding speed.
In theory, the V-shaped area of high-frequency welding temperature distribution of the heat due to the current flowing through the first of the V-shaped area of the resulting decision, thermal conduction of heat determines the penetration depth of the high-frequency current distribution of the weld zone is to look at the strip edges it the penetration depth, the depth of weld penetration is a function of frequency. Characteristics of heat transfer process is that heat penetration depth of the V-shaped zone length and the welding speed functions.
The actual state of high-frequency welding steel pipe are: ① current penetration depth is greater than the penetration depth of the heat, which is the result of a temperature distribution under; ② heat penetration depth is greater than the penetration depth of the current, which is another result of the temperature distribution under; ③ heat penetration penetration depth, which is a transition temperature distribution.