High -frequency welding
The straight seam welding steel pipe is rolled into a round tube -shaped and straight welded through a high -frequency welding unit to form a steel pipe. The shape of the steel pipe can be round or alien. Depending on the fixed diameter rolling after welding.
The high -frequency welding of the steel pipe uses the skin's skin -tending effect and neighboring effect. After rolling the steel (belt), it forms a round tube blank with a cross -section, and rotates in the tube blanket near the center of the induction coil. Or a set of resistors (magnetic sticks), which form an electromagnetic induction loop with the opening of the tube. Under the action of skin tendency and neighboring effects, the edges of the tube opening opening have a strong and concentrated thermal effect. After the edge of the weld is quickly heated to the temperature required to weld and is squeezed by the pressure roller, the melting metal is combined with the crystal, and a solid docking weld is formed after cooling.
