There are many friends who do not know much about electric heating tube have some questions like this? Is the electric heating tube solid? Why is the surface of the electric heating tube not charged?
The electric heating tube is definitely solid and has a filler inside. As for the surface of the electric heating tube with or without electricity, we continue to look at the following.
The role of filler in the electric heating tube:
The filler plays an insulating role between the electric heating wire and the electric heating tube;
The filler conducts the heat emitted by the electric heating wire to the electric heating tube shell; The filler is used to fix the space position of the electric heating wire.
After reading this side, we should know that the surface of the electric heating tube is not charged, the reason also lies in the filling material.
So what are the specific requirements for the filler material?
Have sufficient insulation properties and electrical strength.
Has good thermal conductivity, that is, a high thermal conductivity;
Has a coefficient of expansion similar to the expansion coefficient of the electric heating wire.
Has a chemical inertness to the electric heating wire material;
Has a high degree of heat resistance;
Can withstand rapid changes in temperature characteristics;
Small moisture absorption;
Has high mechanical properties; a wide range of material sources, low prices.
At the same time to meet the above nine requirements is very difficult, because the general good thermal conductivity of the body at the same time is good electrical conductivity, electrical insulation properties of high, its thermal conductivity is very low. In a comprehensive comparison, for electric heating tube in the commonly used filler is also quartz sand, aluminum oxide and magnesium oxide three categories.
Our company's heating tube mainly uses the filler is magnesium oxide, is the best filler material.
Magnesium oxide according to the different working temperature selection of different temperature-resistant magnesium oxide powder. The choice of filler material will directly affect the price and life of the electric heating tube. This is why the reason why a penny is a penny. Magnesium powder from a few thousand a ton to tens of thousands of a ton are available, the main difference with the insulation performance and temperature resistance.
From this point alone, can also understand why the same size of the tube, the shell material is the same case, different manufacturers, the offer will be a lot of error. Each factory positioning is also inconsistent.
