The main components that affect the quality of electric heating pipe are shell, heating wire, magnesia powder and sealing material. The selection principle is high temperature resistance and corrosion resistance.

Stainless steel is usually used for electric heating tubes (304 is the most commonly used material, 316L and 310S are usually selected for corrosion according to the situation, and 310S for high temperature). If you do not know the specific construction environment when making heating pipes, stainless steel 304 is usually used as the shell. Because stainless steel 304 has good plasticity. If the environment of heating is corrosive, titanium alloy and polytetrafluoroethylene are usually chosen to have good corrosion resistance.

Reasonable selection of electric heating pipes is the premise to ensure the quality of heating pipes, which plays a vital role in the future service effect and service life.

For electric heating tube, we mainly consider its effect, life and price. Choosing suitable electric heating pipe should first know its working environment, choose reasonable material according to the working environment, and then the heating platform manufacturer should calculate the correct heating power. Among the factors affecting the quality of electric heating tubes, the quality of materials is a very important one.

Among the factors that affect the quality of materials, the quality of materials is the most important one. Reasonable selection of raw materials for electric heat pipe is the premise to ensure the quality of electric heat pipe.

1. Selection principles of pipe materials: heat resistance and corrosion resistance.

For cryogenic pipes, BUNDY, aluminium and copper pipes are generally used, while stainless steel pipes and Ingley pipes are generally used for high temperature pipes. Ingley 800 electric heat pipe can be used under the condition of poor water quality. Ingley 840 electric heat pipe can have good oxidation resistance and corrosion resistance at high temperature.

2. Selection of Resistance Wire

The resistor wire materials commonly used in the electric heat pipe are Fe-Cr-Al and Cr20Ni80 resistor wires. KAWAI chooses iron-chromium wire of 0Cr25Al5 brand, which has higher melting point and better service life than ordinary iron-chromium wire. The main difference between the two kinds of resistance wires is that the melting point of 0Cr25Al5 is higher than that of Cr20Ni80, but at higher temperatures, 0Cr25Al5 is easier to oxidize, while Cr20Ni80 can maintain stable properties at high temperatures. Therefore, Cr20Ni80 is generally used as resistance wire in high temperature.

3. Selection of Magnesium Oxide Powder

Magnesium oxide powder is located between resistance wire and pipe wall, which is used for insulation between resistance wire and pipe wall. At the same time, magnesium oxide powder has good thermal conductivity. However, magnesia powder has strong hygroscopicity, so it should be treated by moisture-proof treatment (modified magnesia powder or sealing treatment of electric heat pipe) when it is used.

Magnesium oxide powder can be divided into low temperature powder and high temperature powder according to the temperature range used. Low temperature powder can only be used below 400 C, usually modified magnesium oxide powder.