Analysis of the reason why the electric furnace wire does not heat up
After the heating wire is turned into a furnace wire, it is energized and heated. As the temperature rises, the color of the heating wire will gradually become dark red, red, and red, until it turns white, like the color of an incandescent filament. These color changes indicate that the temperature of the heating wire itself is gradually increasing.
When designing electric heating elements, customers often encounter electric heating wires of the same specifications and dimensions. After the elements are designed and processed according to drawings, some can quickly see that the surface of the heating wire is very red after power-on, while some do not see the hair. red. Is there a problem with the quality of different batches of heating wires? In fact, this understanding is a misunderstanding. Whether the heating wire is red, it only represents the temperature of the heating wire itself when it is working.
The temperature of the heating wire itself depends on the surface load, that is, the number of watts per unit surface area. The higher the surface load, the higher the heat generated per unit area per unit time. The faster the heating wire temperature rises, the easier it is red. The lower the surface load, the opposite effect.
Therefore, when designing electric heating elements, the total resistance, surface area (wire diameter) and temperature coefficient of resistance of the heating elements must be considered. At the same time, it is necessary to consider that the resistance values of heating wires of the same brand and specification are different. If these factors are neglected, then the heating rate of the electric furnace wire of the same specification designed in this way will be very different when installed in the furnace. For the electric furnace user, this difference is unacceptable, so it will reduce the user's production efficiency.
It is far from enough to only consider that the total power meets the design requirements.