Triangular magnesium tube

Abstract

The triangular magnesium tube of the invention has a magnesium tube main body with a regular triangle cross section made of dry powder material extracted from seawater magnesium raw material through compression, molding and sintering. The hollow inner cavity is adapted to the spiral resistance wire shape and size of the electric heating tube. The middle section of the three beveled edges is outwardly arcuate, and the protruding part is provided with a feeding groove; Between that electric heat pipe and the resistance wire, the electric heating pipe can provide a fixed support for the resistance wire, and the resistance wire can be prevent from contacting with the metal tube shell due to vibration or other factors, and the support effect is good; A magnesium powder feeding groove facilitatethat magnesium powder to enter the hollow inner cavity of the magnesium tube main body, The tube shrinkage rate of the electric heating tube filled with regular triangular prism magnesium tube and magnesium powder can reach 15% - 20%. After the tube shrinkage, the parameters can be controlled accurately, and it can meet the insulation structure requirements of high temperature heating. The triangular magnesium tube is especially suitable for the electric heating tubes in high voltage explosion-proof heaters with 6600V power supply and 1000KW total power.

Description

technical field [0001] The invention relates to a triangular magnesium tube, which is suitable for an electric heating tube of a high-voltage explosion-proof heater, especially a U-shaped electric heating tube of a high-voltage explosion-proof heater with a power supply voltage of 6600V and a total power of 1000KW. Background technique [0002] The electric heating tube of the electric heater is generally composed of a spiral resistance wire built into the metal tube, and crystalline magnesium oxide powder is filled between the resistance wire and the metal tube. The magnesium powder forms an insulating structure between the heating wire and the tube wall, and has outstanding However, magnesium powder also has strong hygroscopicity, so moisture-proof treatment should be carried out when using it; moreover, after the metal tube is filled with magnesium powder, the pipe diameter needs to be compressed to increase the causative effect of the magnesium powder filler in the heatin...

AI Technical Summary

Problems solved by technology

[0002] The electric heating tube of the electric heater is generally composed of a spiral resistance wire built into the metal tube, and crystalline magnesium oxide powder is filled between the resistance wire and the metal tube. The magnesium powder forms an insulating structure between the heating wire and the tube wall, and has outstanding However, magnesium powder also has strong hygroscopicity, so moisture-proof treatment should be carried out when using it; moreover, after the metal tube is filled with magnesium powder, the pipe diameter needs to be compressed to increase the causative effect of the magnesium powder filler in the heating rod. Density, so that the density of the filling material in the heating tube reaches about 3.5g / cm3, so as to achieve the purpose of not reducing the insulation resistance and improving the thermal conductivity; after shrinking the tube, all parameters of the heating tube will change, and the resistance value of the spiral resistance wire in the heating tube It also changes accordingly. The shrinkage rate of traditional heating tubes after filling magnesium powder is low, only 8% to 14%, and it is impossible to accurately control the parameter changes after shrinkage, especially for power supply voltage 6600V and total power of 1000KW. The electric heating tube in the high-voltage explosion-proof heater has high requirements on the insulation layer between the resistance wire and the metal tube. The magnesium powder insulation structure of the traditional heating tube cannot meet the requirements of the electric heating tube of the high-voltage explosion-proof heater.

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