Filled magnesium oxide mineral insulated cable and preparation method thereof

Abstract

The invention discloses a filled magnesium oxide mineral insulated cable and a preparation method thereof. The preparation method comprises the following steps of: (1) calcining heavy magnesium oxide powder at a high temperature of 850-950 DEG C to remove impurities, then uniformly mixing the calcinated heavy magnesium oxide powder with potassium tetrafluoroaluminate powder, and placing the mixture in a heat preservation furnace for heat preservation; (2) putting a required wire core material into a copper pipe on an assembly table for blank assembly, and fixing one end of the copper pipe; (3) before filling, adopting a magnetic separator to remove magnetic metal inclusions, then pouring the mixed powder into a gap around the copper core in the copper pipe, and using a tamping mechanism for tamping the mixed powder until the mixed powder is filled well while pouring is conducted; and (4) subjecting the wire core copper pipe filled with the mixed powder to stretching, annealing, stretching again and annealing again until a wire core copper pipe meeting the design specification and size is stretched out. The problems that an existing magnesium oxide powder automatic filling method is low in compactness and poor in impact resistance and uniformity are solved.

Description

technical field

[0001] The invention relates to a filling magnesium oxide mineral insulated cable and a preparation method thereof, belonging to the field of insulating materials. Background technique

[0002] Mineral insulated cables are cables composed of inorganic mineral materials, usually made of magnesium oxide powder as the mineral insulating layer compressed and compacted, its melting point (2800 ° C) far exceeds the melting point of copper sheath (1083 ° C), and the resistivity is affected by temperature changes Small impact, excellent electrical insulation and heat dissipation at high temperatures, as an inorganic mineral material, has high fire resistance, smoke-free, non-toxic, safe, large carrying capacity, strong overload resistance, corrosion resistance, waterproof, explosion-proof, mechanical With the advantages of good performance and convenient laying, it is especially suitable for places with extremely high safety requirements and extremely harsh environme...