Use electric heating wire for hot cutting (cutting sponge, foaming, etc.). After the electric heating wire is energized, the length will be long and loose. The solution and elastic compensation can be selected with suitable spring force. You can refer to the hacksaw and add an adjustable screw that can be wound on the side. When it is long, it is twisted and twisted tightly. Regarding the temperature, the voltage can be adjusted, and the resistance is adjusted (that is, the length of the heating wire). The longer the electric heating wire is, the higher the resistance is, and the lower the temperature is.
Electric furnace wire generally has a high resistance alloy. High-resistance alloy, nickel-chromium wire up to 1250 degrees, iron chrome aluminum wire up to 1400 degrees of heating wire is an important parameter, is the surface power. The resistivity is too large, and the surface power is large after a certain current is applied. Therefore, for small power appliances, small diameter and small current are used, but the magnitude of the current is determined by the size of the resistor. The length and diameter of the heating wire are calculated. After the electric furnace wire electric heating tube is blown, it is continuously used after being connected, and the joint is not well contacted, the contact resistance is large, and the temperature is high, so it is easier to blow. The two electric furnace wires are contacted in multiple turns to increase the contact area and reduce the temperature. Blow or cut off, the length is shorter than the original, the resistance is smaller than the original, according to U2 / R = P power will increase, pay attention to safe use.