What is an induction furnace heating coil?
The induction furnace heating coil is the main part of the induction heating of the medium frequency furnace. It is made of a rectangular red copper tube and has a spiral shape. It is used in conjunction with an medium frequency power supply. So, what is the specific heating principle, function and structure of the induction furnace heating coil?
Heating principle of induction furnace coil:
The induction furnace’s medium frequency power supply frequency conversion device converts the three-phase 50Hz alternating current into a single medium frequency current of 100Hz-8000Hz after rectification and inversion. After being input into the medium frequency furnace coil, it generates a high-density magnetic field. The magnetic field cuts the metal in the medium frequency furnace coil to generate eddy currents. The self-heating realizes the purpose of metal heating.
Induction furnace coil heating function:
The function of the induction furnace heating coil is to make the medium frequency current pass through the spiral induction coil of the medium frequency furnace to generate a magnetic field. The size and distribution range of the internal magnetic field of the medium frequency furnace coil are determined by the design of the induction coil, that is to say, the size of the rectangular copper tube of the medium frequency furnace heating coil , The number of turns and the diameter of the induction coil have a lot to do with.
The structure of induction furnace coil heating:
The coil heating of the induction furnace is made of a rectangular red copper tube according to the design requirements and the specific requirements of copper tube specifications, diameter and number of turns, which are wound on a winding machine. Copper screws are welded on the coil, and bakelite posts with a certain distance between turns are installed on the copper screws to fix the distance between turns of the coil and keep the shape of the heating coil of the medium frequency furnace unchanged. The coils are generally sprayed with insulating paint, winding mica tape, winding glass ribbon, and insulating varnish curing, and then insulation treatment, and then knotting the furnace lining to protect the coil, assisting in the fixing of the bottom support, the stainless steel furnace mouth plate, the outer rubber wood, the waterway, Vertical row and snap-on connection row, etc., form a complete medium frequency furnace coil.
Classification of induction furnace coil heating:
Induction furnaces are divided into medium frequency heating furnaces and medium frequency smelting furnaces. The coils are also divided into medium frequency furnace heating coils and medium frequency furnace smelting coils; medium frequency furnace heating coils are also called inductors and diathermic furnace coils, and smelting coils are also called smelting furnaces. Coil.
Specification of copper tube heated by induction furnace coil:
Commonly used specifications of induction furnace heating coils are:
10×10×2mm 12×14×2mm 14×16×2mm 16×18×2mm 18×20×2mm 20×10×2mm 22×18×2mm 24×15×2mm 25×20×2mm 26×20×2mm
Precautions for the use of induction furnace coil heating:
- The heating coil of the medium frequency furnace is used in a poor environment, especially in the foundry and melting workshop, where there is a lot of dust or iron filings. Since iron filings or iron dross are easy to fall on the medium frequency furnace coil, this will cause the inter-turn surface of the medium frequency furnace coil to be carbonized. In the case of a short circuit between turns of the medium frequency furnace coil, inter-turn ignition occurs, which will break down the copper tube of the medium frequency furnace coil and cause an medium frequency furnace failure. Therefore, it is necessary to frequently clean the production and use site of the medium frequency furnace, and the focus is on the furnace wire of the medium frequency furnace to the coil of the medium frequency furnace.
- When we inspect and repair the heating coil water circuit of the medium frequency furnace, we must pay attention to the direction of the cooling water inlet and outlet of the medium frequency furnace coil. The correct direction of the cooling water is downward and upward to avoid the waterway. Only in this way can there be enough water flow in the medium frequency furnace coil to ensure the cooling effect of the medium frequency furnace coil.
- Regardless of whether the medium frequency furnace is used for diathermy or smelting, pay attention to the use of the furnace lining. If the lining of the medium frequency heating furnace is broken, the metal oxide scale will fall on the coil, causing a short circuit between turns. The lining of the medium frequency smelting furnace is broken and the lining becomes thinner, and the molten steel flows through the lining and flows to the induction coil. In this case, the high temperature molten iron will burn the induction coil of the medium frequency furnace. Therefore, it is necessary to check the lining material of the medium frequency furnace frequently to avoid damage to the lining caused by rapid cooling and heating.