The impact of high-frequency welding on the quality of steel pipe, welding technology and technical parameters of the control, the induction coil and the placement of the resistance of the orientation of the weld quality of steel pipe welding, the following four aspects about.
1) Weld seam weld control of steel into the welded pipe unit by the forming roll, the guide roller orientation, the formation of a circular gap with a hollow tube, adjust the amount of kneading the kneading roll, making the weld gap control in 1 -3mm, and keep the two ends of the weld flush. Weld gap control too large, will make the welding seam is not welded or cracking bad; weld gap control too small, because the heat is too large, the formation of the weld burning, molten metal splash, affecting the welding quality of the weld.
2) High-frequency induction coil orientation control loop should be placed in the same base line with the steel tube, induction coil front end from the base line of the kneading roll line spacing, without prejudice to the premise of kneading roll should be regarded as the standard steel pipe as close as possible. If the induction ring away from the kneading roll far, the effective heating time longer, wide heat affected zone, making the strength of welded steel pipe decreased or incomplete penetration; the other hand induction ring easily burned kneading roll.
3) Impedance azimuth regulator is a or a group of dedicated welding rod bar, the cross-sectional area of the resistor should not be less than 70% of the cross-sectional area of the inner diameter of the pipe, its role is to make the induction coil, the weld bead margin and magnetic rod form an electromagnetic induction loop, the proximity effect occurs, the eddy current heat concentrated in the vicinity of the weld bead margins, so that the edge of the tube heated to the welding temperature. Impedance should be placed in the V-zone heating section, and the front end of the base roll in the direction of the roller so that the base line and the tube base line common. If the orientation of the impeller is not good, it will affect the welding speed and welding quality of the welded pipe, causing the crack of the steel pipe.
4) Technical parameters of high-frequency welding - Input heat control high-frequency power input to the pipe weld heat is called the input heat.
