Fire-resistant cables, also known as mineral-insulated cables or magnesium oxide cables, are copper-core, copper-sheathed cables whose insulation is made from the mineral material magnesium oxide powder. Mineral-insulated cables consist of two inorganic materials: copper conductors and magnesium oxide, encased in a copper sheath. The cable’s structure features an electrical-grade copper rod as the core conductor and a smooth, golden-colored tube as the sheath; the inorganic mineral magnesium oxide powder is processed into an insulating material. As a result, these cables possess numerous unique properties.

　　(1) Excellent fire-resistant performance. The copper used as both the cable jacket and conductor has a melting point of 1083℃, and the magnesium oxide powder insulation material does not melt even at high temperatures of 2200℃. Consequently, the entire cable is non-combustible and cannot catch fire. Fire-resistance tests have shown that a live fire-resistant cable can withstand burning in flames ranging from 800 to 1000℃. In contrast, cables with organic insulation and jacket layers will spontaneously combust at temperatures between 380 and 430℃. During combustion, these cables release large amounts of heat, which further elevates the temperature and promotes the spread of the fire. Moreover, the insulation material loses nearly all of its mechanical strength and insulating properties, failing to protect the conductors and allowing the cable to continue conducting electricity.

　　(2) High temperature resistance. As the insulation material for fire-resistant cables, magnesium oxide powder, protected by a copper sheath, can ensure normal power supply and remain undamaged even when exposed to a flame at 1000℃ for a short period of time.

　　(3) Smoke-free and non-toxic. Magnesium oxide-insulated fire-resistant cables neither emit smoke nor produce harmful gases when exposed to flames.

　　(4) Explosion-proof. The magnesium-based insulating material can be firmly pressed between the copper core and the copper sheath, preventing flammable gases, vapors of easily combustible liquids, and flames from entering the cable.

　　(5) Corrosion resistance. The copper sheath is corrosion-resistant and generally does not require additional protective measures. In environments with severe chemical corrosivity, a plastic protective layer can be used to safeguard the copper sheath.

　　(6) Waterproof. The copper sheath features a smooth copper protective layer that allows for prolonged electrical conductivity even when submerged in water.

　　(7) High current-carrying capacity. Compared with other types of cables having the same core cross-section, magnesium-based fire-resistant cables have longer continuous operating times, higher current-carrying capacities, and stronger overload capabilities.

　　(8) High mechanical strength. The jacket is made of copper, which is very robust and will not be damaged in structure even when subjected to typical mechanical impacts and external forces.

　　(9) Long service life. The materials used to construct fire-resistant cables—copper cores, copper sheaths, and magnesium oxide powder—are chemically stable inorganic materials; therefore, there is no issue of insulation aging, making these cables virtually suitable for permanent protection.

　　(10) Safe and reliable. The copper sheath of the fire-resistant cable itself serves as an excellent grounding conductor, ensuring the safety of personnel during work.

　 　Features and Applications of Fire-Resistant Cables

　　It features a small outer diameter, grounding capability, waterproof and explosion-proof performance, corrosion resistance, high mechanical strength, large current-carrying capacity, and high operating temperature. It is widely used in applications such as high-rise buildings, petrochemical facilities, airports, tunnels, ships, offshore oil platforms, aerospace, iron and steel metallurgy, shopping centers, and parking lots.

Free consultation hotline:
0573-86400983

Emergency hotline:
Mr. Wang:13906833990

Corporate email:
qinshan@qinshancable.com

Company Address:
No. 218, Changfeng West Road, Qinshan Nuclear Power Related Industry Zone, Haiyan County, Zhejiang Province