How does the high frequency welding pipe mill use the skin effect of high frequency current to achieve fast and high quality welding?

Publish Time: 2025-01-14

The high frequency welding pipe mill uses the skin effect of high frequency current to achieve fast and high quality welding. The following are its specific working principles and steps:

1. The basic principle of the skin effect

The skin effect refers to the uneven distribution of current on the cross section of the conductor when alternating current passes through the conductor, and the current density is higher near the surface of the conductor and lower in the center of the conductor. The higher the frequency, the more concentrated the current is on the surface of the conductor.

In high frequency welding, using this effect, the current is mainly concentrated on the surface of the pipe, thereby generating a large amount of heat in the welding area without consuming energy on the entire pipe.

2. Composition of high frequency welding pipe mill

High frequency generator: converts low frequency alternating current into high frequency alternating current, usually with a frequency between tens of kilohertz and several megahertz.

Induction coil: high frequency current passes through the induction coil to generate a high frequency magnetic field.

Pipe: The metal pipe to be welded generates a large amount of heat on the surface through the skin effect under the action of the induction coil.

3. Welding process

Pipe forming: First, the metal strip is rolled into the required tubular shape by a forming machine.

High-frequency induction heating: The formed pipe enters the high-frequency welding pipe mill. The high-frequency magnetic field generated by the induction coil induces eddy currents at the edge of the pipe (welding area). The current is concentrated on the surface of the pipe and quickly heats the welding area.

Welding area heating: Due to the skin effect, the welding area (edge of the pipe) heats up rapidly and the metal reaches a molten state.

Extrusion welding: While heating, the edge of the pipe is squeezed by the extrusion roller. The molten metal fuses together under pressure to form a firm welded joint.

Cooling and forming: After welding, the pipe enters the cooling device, quickly cools and shapes, and finally forms a high-quality welded pipe.

4. Advantages of high-frequency current

Rapid heating: The skin effect of high-frequency current concentrates the heat in the welding area, and the heating speed is very fast. It usually only takes a few seconds to complete the welding, which improves production efficiency.

Energy saving: Since the current is concentrated on the surface, the energy utilization rate is high, which avoids unnecessary energy consumption and reduces energy waste.

High welding quality: Due to the uniform and controllable temperature in the welding area, the welding joint is of high quality, the weld is strong, and the weld surface is smooth, reducing the need for subsequent processing.

5. Application areas

High frequency welding pipe mill is widely used in the production of metal pipes such as steel pipes, stainless steel pipes, galvanized steel pipes, etc., and is particularly suitable for large-scale and high-efficiency production needs.

High frequency welding pipe mill achieves rapid heating and high-quality welding in the welding area by utilizing the skin effect of high-frequency current. This welding method is not only efficient, but also has low energy consumption and excellent weld quality, so it is widely used in modern industry.