Have many friends who don't know much about electric heating tubes ever had such questions? Is the electric heating tube solid? Why is the surface of electric heating tube not charged?

Many friends who buy electric heating tubes have asked these questions. As a matter of fact, I can understand these questions after reading what I have introduced to you.

The electric heating tube must be solid and filled. As for whether the surface of the electric heating tube is electrified, let's continue to look down;

Role of filler in electric heating tube:

1. The filler plays an insulating role between the electric heating wire and the electric heating tube;

2. The filler transmits the heat generated by the electric heating wire to the electric heating tube shell;

3. The filling material is used to fix the space position of the heating wire.

After reading this, we should know that the surface of the electric heating tube is not charged, and the reason lies in the filling material.

What specific requirements do we have for filling materials?

1. Have sufficient insulation performance and electrical strength;

2. Good thermal conductivity, i.e. high thermal conductivity;

3. The expansion coefficient is similar to that of the electric heating wire;

4. It is chemically inert to the heating wire material;

5. High heat resistance;

6. Be able to withstand the characteristics of rapid temperature change;

7. Low moisture absorption;

8. High mechanical performance;

The material source is extensive and the price is low.

At the same time, it is very difficult to meet the above nine requirements, because generally good heat conductors are good conductors at the same time. If the electrical insulation performance is high, its thermal conductivity is very low. By comprehensive comparison, the commonly used fillers in electric heating tubes are quartz sand, alumina and magnesium oxide.

The main filler we use is magnesium oxide, which is a good filler at present.

Magnesium oxide selects different temperature resistant magnesium oxide powder according to different working temperature. About this problem, I have introduced it to you before (Reference: Yufei: analysis of electric heating pipe industry standard | selection regulations of filling insulating materials)

The selection of unused filling materials will directly affect the price and service life of electric heating tubes. This is why you get what you pay for. Magnesium powder varies from thousands of tons to tens of thousands of tons. Its main difference is insulation and temperature resistance.

Article source: heat pipe manufacturer http://www.gdtamman.com