Full technical breakdown Lapp ÖLFLEX CRANE NSHTÖU 0.6/1 kV (max 1.2 kV): specialized motorized drum cable for cranes (gantry, bridge, portal, jib) with extreme cold capability -25°C to -40°C dynamic. NSHTÖU per VDE 0250-814: N (normalized), S (hose-type), H (special elastomer), T (trommel/drum), Ö (oil-resistant), U (reinforced). Works at spool speeds up to 120 m/min in repeated flex. Core problem: standard neoprene outers become brittle below -25°C and crack during drum bending. Arctic version uses modified elastomer compound (5GM5-Arctic) with plasticizers that don’t crystallize at sub-zero, ensures -40°C operation. Configuration 4G50: tinned Cu Cl.5, special EPR 3GI3 insulation, internal anti-skewing rubber extrusion, outer Arctic-grade neoprene or PUR. OD ~18–22 mm, weight ~0.85–1.1 kg/m, current ~250–280 A. Alternatives: (1) FeiChun NSHTÖU-Cold — Lapp equivalent with Arctic compound, -40°C dynamic, better price; (2) FeiChun PUR Reeling Cable — PUR sheath, -50°C capable, 15–20% lighter, preferred for Arctic/Siberia. Russian GOST alternatives (КГРПУ, КГЭЖ-ХЛ) require TU modification for drum application.
Underground mining electrical installations present extraordinary challenges distinguishing them from conventional industrial power distribution applications. The confined space constraints of underground workings limit access for cable installation and maintenance operations. The presence of moisture, whether from groundwater infiltration, ventilation condensation, or wet mining processes, creates persistent electrical insulation challenges. The mechanical stress imposed by coal cutting equipment, continuous miner operations, and mobile machinery movements subjects cables to continuous flexing, abrasion, and impact loading that would rapidly destroy standard industrial cables. The potential presence of explosive atmospheres in coal mines necessitates stringent electrical safety requirements preventing ignition sources. According to operational experience documented by Australian mining operations specialists, cable failures represent one of the leading causes of unplanned production interruptions in underground mining operations, with properly specified and installed cable systems demonstrating service lives of five to eight years compared to six to eighteen months for inadequately specified alternatives.
BS 6708 Type 21 mining cable represents an advanced variant of galvanized steel pliable wire armoured flexible cables specifically engineered for demanding mining and quarrying applications requiring a dedicated fourth earth conductor. This four-core configuration distinguishes Type 21 from the three-core Type 20, providing enhanced safety features and compliance with electrical regulations that mandate separate protective earth conductors in mining installations.
Key Identification: Type 21 cables feature four unscreened cores (three phase conductors plus one earth conductor) laid up around an elastomeric cradle without contacting each other, protected by galvanized steel pliable armour between inner and outer sheaths. Rated at 640/1100V with a 3kV test voltage, these cables are designed for use in deep mines where explosive gases and dust can accumulate, as well as surface operations supplying excavating, crushing machines and equipment.
BS 6708 Type 20 mining cable represents a specialized category of galvanized steel pliable wire armoured flexible cables engineered for the most demanding mining and quarrying applications. This cable type is characterized by its robust construction featuring three unscreened cores laid up around an elastomeric cradle without contacting each other, protected by galvanized steel pliable armour that provides exceptional mechanical protection while maintaining the flexibility essential for mobile mining equipment applications.
Key Identification: Type 20 mining cables are classified within BS 6708 as cables with galvanized steel pliable wire armouring, featuring unscreened cores and a rated voltage of 640/1100V. These cables are specifically designated for use in deep mines where explosive gases and dust can accumulate, as well as surface operations for supplying excavating, crushing machines, and equipment requiring robust mechanical protection.