At present, the main filling materials for electric heating tubes are quartz sand and alumina. Why is cable-grade magnesium oxide powder the main filling material? Next, I will explain it to you in detail.Low iron magnesia

Mainly because it is an electrical insulator, a good conductor of heat, high safety, cheap, easy to buy, and has a large storage capacity, so cable-grade magnesium oxide powder has been widely used in electric heating pipes for a long time.

Magnesium oxide needs to be melted at a temperature of 2800 degrees after refining, so that the crystal is completely stabilized and cooled into a block. Due to the influence of cohesion, the purity of the middle part is relatively high (specific gravity 3.58-3.6). This block is crushed by an iron hammer and then sent out. After the iron filings are mixed with the mesh, the magnesium oxide powder used as the filling material is now used, and the mesh specification used now is 40-325 mesh.

What is Cable Grade Magnesium Oxide Powder? What are the categories and features?

Cable-grade magnesia powder refers to fused crystalline magnesia blocks that are crushed and matched with different particle sizes (mesh) in a certain proportion, and used directly or after modification in tubular electric heating elements as an insulating medium for heat conduction at high temperatures.

Low iron magnesia

Classification

Ordinary magnesium oxide, classification code P;

Low temperature moisture-proof magnesium oxide, classification code D;

Medium temperature moisture-proof magnesium oxide, classification code Z;

High temperature magnesium oxide, classification code G.

Features

① It has good insulation performance and electrical strength.

② It has good thermal conductivity and can conduct the heat from the heating wire to the metal tube.

③ Good heat resistance and vibration resistance.

④ It is easy to adsorb carbon dioxide and water in the air, and is slightly soluble in pure water. After absorbing carbon dioxide, the solubility increases rapidly, and it reacts with water to form magnesium hydroxide, which reduces the insulation resistance rapidly. For the electric heating tube filled with magnesium oxide, the point insulation performance will be reduced, resulting in electrical breakdown and damage to the electric heating tube.