Basic knowledge and introduction to structure of electric heating tube

Use simple words to analyze and explain basic structure of an electric heating tube. Let's break down basic structure of an electric heating tube into a few small tasks.

1. What is heating element of electric heating tube?

The heating element of electric heating tube is an electric heating wire, mainly iron-chromium-aluminum and nickel-chromium alloy. Iron-chromium-aluminum is cheaper, usually there is no special instruction, and iron-chromium-aluminum alloy wire is used in 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 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 surface of electric heating tube charged?

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

Electric heating tubes are widely used for heating liquids because their surface is not charged. So why isn't surface of electric heating tube charged? This is because gap between heating wire and body of electric heating tube is usually filled with powder, and magnesium oxide powder filler is both insulating and heat-conducting.

3. How does an electric heating tube provide internal insulation without absorbing moisture?

From second question, we know that surface of electric heating tube is not charged due to insulating filler, so how can electric heating tube be insulated and not absorb moisture?

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

Secondly, end of electric heater pipe is properly sealed (how to choose sealing material for the electric heating pipe, we will explain in detail later).

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

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

The reason we explained above and then this problem, I think difference between electric heater tube and electric heating wire is that electric heater tube has a metal sheathed tube, main one being stainless steel (sus201 , 304 , 321, 316, 310 etc.), copper, carbon steel (iron).

Choose different metal sheathed pipes according to working conditions. From now on, we can get fourth basic design of electric heater tube: metal sheathed tube.

The main structure of electric heater pipe is mainly composed of these four, and rest are small structures, let's take a look at following set of images.

In addition to four main aspects presented above, in this figure we also see that basic design of electric heater tube also includes: insulators, lead rods, terminals, etc.

I think through my introduction, you should have a very clear understanding of basic structure of an electric heating tube, and you should have a clear idea of ​​what an electric heating tube is!