The spiral tube performs important control in the temperature of the squadron in the welding process. The incentive frequency of the steel pipe is controlled by the capacitance, the square of the inductor in the incentive circuit, and The current can change the size of the incentive frequency to achieve the purpose of controlling the welding temperature. For low -carbon steel, the welding temperature of the spiral tube is controlled at 1250 ~ 1460 ° C, which can meet the tube wall thickness 3 ~ 5mm welding requirements. The welding temperature can also be achieved by adjusting the welding speed.
The welding temperature of the spiral tube is mainly affected by the high -frequency vortex heat power. According to the formula, the high -frequency vortex heat power is mainly affected by the current frequency. Effects of voltage, current and capacitance, and inductance. There are many conditions in the production process of steel pipes. For different situations and design principles, it is continuously used and promoted in the industry. The incentive frequency formula is: F = 1/[2π (CL) 1/2].
In the formula: F-incentive frequency (Hz); C-incentive circuit capacitor (F), capacitance = power/voltage; induction in L-incentive circuit
When the input heat is insufficient, the edge of the heated welds cannot reach the welding temperature, and the metal tissue still maintains a solid state to form unfample or unprovoed. Curvi or melting droplets cause welding seams to form a melting hole.
In the process of welding and production, the spiral tube adopts important standard process parameter design and processing. During the process of processing, the different design needs are used in different industries. Rolling, with steel gradually rolled up, forming a circular tube blank with an open space, adjusting the pressure of the squeezing roller, controlling the weld gap at 1 ~ 3mm, and the two ends of the weld are flat. If the gap is too large, the adjacent effect will be reduced, the hearing heat is insufficient, and the welded seam crystals are indirectly combined with the molten or cracking. If the gap is too small, the neighboring effect is increased, the welding heat is too large, causing welding seams to be damaged; or the weld is squeezed and rolled to form a deep pit, which affects the surface quality of the weld.
