Pakistan can produce quality fireproof electricity cables by taping the abundant indigenous deposits of mica, a critical raw material used to insulate cables and conduct heat, and which is imported at a high cost.

Talking about the mining of mica in Pakistan as an indigenous source to produce low-cost fireproof/heat-resistant electric wires, Muhammad Yaqub Shah, a principal geologist in Global Mining Company Limited, Islamabad, told WealthPK: “Mica is the only unusual solid material that is a good heat conductor and an electrical insulator. It not only stabilises the flow of current, but also reduces the cost of energy. It is used in both powdered and sheet forms.”

He said micas were a group of silicate minerals occurring as large crystals often called books. “They are of many types like sericite or white mica, biotite or black mica, phlogopite or brown mica, fuchsite or green mica, etc.” He said the majority of micas were found in igneous rocks, pegmatites, and rarely in metamorphic rocks. “Brown mica is also a source of lithium extraction.”

Muhammad Yaqub said mica’s deposits were abundantly found in the northern areas of Pakistan, and in Balochistan to some extent. “Mica sheet of over four inches is highly valuable, between two to four inches is considered medium and below is of low grade.”

He said mica’s powdered/sheet was widely used to produce industrial items like cosmetics, mica paper/tape, heatproof glass, etc. “The most common use is the insulation of a variety of electrical/electronic equipment like car batteries, engines, blast furnaces, critical wiring circuits, heaters, boilers, lumber kilns, metal smelters, tanks, home appliances, electronics, microscopy, navigation compasses, optical fibres, shimmering, diaphragms for oxygen breathing, thermal insulation of window panels, lamps, gauge glass, etc.”

Discussing with WealthPK about the raw material used to produce fire-resistant cables, general manager (marketing and sales) of FR Cables, Usman Farooq said: “FR Cables is a known name to produce fire-resistant low-smoke and zero-Halogen (LSZH) electric power cables. FR Cables manufactures LSZH cables, which are resistant to fire up to 250 Degree Celsius and provide time of protection for about 30 minutes.”

He said to enhance the resistance mica tape was used along with LSZH, which increased the resistance time by up to three hours and could resist the flame temperature of about 750 Degree Celsius.

“Such safety cables with the addition of mica tape are rather costly than the other conventional Poly Vinyl Compounds (PVC) cables. Mica tape is imported at a high cost, thus increasing the prices of such wires/cables.”

Bilal-ur-Rasool, assistant sales officer at Engro Polymer and Chemicals (EPCL), told WealthPK that the company had a production unit in Karachi having a capacity of producing 295,000 tonnes of PVC per annum. “With the addition of different chemicals, it is widely used to produce fire-retardant/heat-resistant wires and cables in the country.”

Talking about the importance of fire/heat safety cables and local production of mica tape, Nasir Mehmood, quality control in-charge at GM Cables, said fireproof cables or safety cables were used as control cables to keep the electricity flow regular in case of any fire emergency. “Mica tape and LSZH or PVC casings are used as an addition to make them fireproof.”

He maintained that mica tape was used to withstand temperatures up to 1,000 Degree Celsius, allowing the electrical equipment to operate smoothly. “Thin mica paper reinforced with adhesives is used to coat the cables and wiring available in sizes ½ to 2 inches. It also makes them highly resistant to alkalis, acids, dampness, water, shocks, and radiation.”

Nasir Mehmood also said GM Cables was producing PVC-coated heat-retardant cables, adding the company was also planning to produce fireproof cables.  He said the high price of fireproof cables was because of the mica tape import. “PVC resins are available in Pakistan as about 98% of the need is fulfilled locally. But the mica tape is not manufactured locally.”

Credit : Independent News Pakistan-WealthPk