Basic knowledge and structure introduction of electric heating tube

Basic knowledge and structure introduction of electric heating tube

1. What is the heating element of the electric heating tube?

The heating element of the electric heating tube is an electric heating wire, mainly iron-chromium-aluminum and nickel-chromium alloy wire. Iron-chromium-aluminum is cheaper, generally there is no special instruction, and the iron-chromium-aluminum alloy wire is used in the electric heating tube. Nichrome wire is more expensive.

Difference: The working temperature of iron-chromium-aluminum alloy materials can reach 1400°C, which is enough to meet the needs of electric heating tubes. However, nickel-chromium wire has good flexibility and good oxidation resistance, while iron-chromium-aluminum wire is relatively brittle.

2. Is the surface of the electric heating tube charged?

We all know that the heating wire of the heating element is charged, so is the surface of the electric heating tube charged? The answer is no.

Electric heating tubes are widely used in heating liquids because the surface is not charged. So why is the surface of the electric heating tube not charged? That's because the gap between the heating wire and the shell of the electric heating tube is generally filled with magnesium oxide powder (MgO), that is both insulating and thermally conductive.

3. How does the electric heating tube achieve internal insulation without moisture absorption?

From the second question, we know that the surface of the electric heating tube is uncharged due to the insulating filler(MgO). So how can the electric heating tube be insulated internally and not absorb moisture?

First, choose high-purity modified magnesium oxide powder (insulating filler);

Second, that is, the end of the electric heating tube is properly sealed

4. What is the difference between electric heating tube and electric heating wire?

The main difference between the electric heating tube and the electric heating wire is that the surface of the electric heating tube is not charged, and the surface of the electric heating wire is charged.

We have explained the reasons above, so I think the extension of this problem is that the difference between electric heating tubes and electric heating wires is that the electric heating tubes have metal sheaths, mainly stainless steel (sus201, 304, 321, 316, 310, etc.), copper, carbon steel (iron).

Choose different metal sheath tubes according to different working environments.