How to control the location of the high-frequency induction coil

Excitation frequency straight seam piling pipe in the excitation circuit capacitance, inductance is inversely proportional to the square root, or the voltage and current proportional to the square, as long as the change in the circuit capacitance, inductance, or voltage and current can change the size of the excitation frequency, so as to achieve control of welding temperature. For low carbon steel, welding temperature control in the 1250 ~ 1460 ℃, can meet the pipe wall thickness 3 ~ 5 mm penetration requirements. In addition, the soldering temperature can be achieved by adjusting the welding speed.

The two edges of tube is heated to welding temperature, oil casing in the extrusion roller extrusion, to form a common metal grain mutual penetration, crystallization, and ultimately form a solid weld. If the extrusion pressure is too small, the number of crystals formed on the small joint, weld metal strength was declining, the force will crack.

Weld by welding and extrusion welding scars will produce, need to be cleared. The removal method is on the rack cutter, pipe fast motion by the burr gelling. Pipe inside burr is generally not cleared. However, if the extrusion pressure is too large, will make the molten weld metal is extruded, not only reduces the weld strength, and will generate a lot of internal and external burrs, and even cause defects such as weld seam ride. When the heat input is low, the heated soldering temperatures reach the edge of the weld metal structure remains solid, forming incomplete fusion or penetration. Soldering temperature is mainly affected by the impact of high-frequency eddy current heating power, according to the relevant formulas can be learned, high-frequency eddy current frequency heating power is mainly affected by the impact of thermal power and eddy current excitation frequency is proportional to the square; while current excitation frequency and by the excitation voltage, current, and capacitance, inductance.