Let's introduce HFTGB cable to industry colleagues and briefly explain its structure, standards, and advantages for your reference.
HFTGB is a copper-core, flexible, synthetic mineral-insulated, stainless steel-sheathed fire-resistant cable. It is installed indoors, in pipelines, cable trenches, cable trays, and other locations subject to mechanical forces. HFTGBY copper-core, flexible, synthetic mineral-insulated, stainless steel-sheathed, polyolefin-sheathed fire-resistant power cable is installed outdoors in humid environments subject to mechanical forces.
HFTGB cable models: HFTGB cable, HFTGB(Y) cable, HFZGB cable, HFKGGB cable, HFKGGBY cable
Proper name: Flexible synthetic mineral-insulated fire-resistant cable
HFTGB cable structure
The HFTGB cable series of flexible synthetic mineral-insulated fire-resistant cables uses stranded copper conductors, coated with a mineral oxygen-barrier tape, then extruded with a synthetic mineral insulation material, then covered with a synthetic mineral tape, and finally spirally wrapped with a non-magnetic stainless steel tape. In applications where the metal sheath must not be exposed, a low-smoke, halogen-free sheath can be added.
This product is a domestic first, with no international prototypes. Compared to the BTTZ series metal-sheathed cables, it maintains exceptionally high fire resistance and electrical durability. It can be used in continuous, long-length, multi-core cables up to 120 mm², eliminating the need for excessive joints. Furthermore, the stainless steel sheath significantly improves mechanical properties and environmental corrosion resistance. However, this product also possesses a complex structure, and the stainless steel sheath's relatively weak conductivity makes it unsuitable for replacing ground wires like copper sheaths. Its overall cost is relatively high among mineral cables.
1. Product Implementation Standard:
GB/T 12706.1-2008 "Extruded Insulated Power Cables with Rated Voltages of 1 kV (Um=1.2 kV) to 35 kV (Um=40.5 kV) Part 1"
2. Fire Resistance Test Standard:
BS6387:1994 "Performance Requirements for Cable Integrity Under Fire Conditions"
3. Basic Technical Requirements
① Installation Location: Indoor or outdoor (selected based on cable model and applicable scope).
② Laying Method and Temperature: Cable trench, cable tunnel, overhead bridge, cable mezzanine; the ambient temperature during installation must be no less than 0°C.
③ Laying Environment: Cables can be laid openly; simple and economical methods such as brackets and hangers can be used in different environments.
4. Cable Operating Conditions
① Operating Temperature: -40°C to 180°C; during a short circuit (maximum duration not exceeding 5 seconds), the maximum temperature of the copper core cable conductor must not exceed 950°C.
② Short-circuit duration shall not exceed 5s.
③ Rated frequency: 49-61Hz;
④ Cable operating environment: Ambient temperature: -40°C to 180°C;
⑤ Bending radius: The cable bending radius should be no less than 7 times the cable's outer diameter;
5. Product Advantages:
① Fire resistance
The HFTGB series fire-resistant cable's outer sheath is made of non-magnetic stainless steel in a threaded pattern. This not only maintains the cable's inherent flexibility and flexibility, but also enhances its fire resistance. It also protects against scratches during construction and rodent bites during use, and helps dissipate heat during use, comparable to conventional cables. These materials themselves are non-flammable and cannot burn or support combustion.
These materials also have a high melting point of over 1300°C. Therefore, the HFTGB series fire-resistant cable can function normally even in flames as high as 1000°C, making it a truly fire-resistant cable.
② Patented Technology - Flexible Synthetic Mineral Insulation
Flexible synthetic mineral insulation material is made from silicone rubber as a base material, combined with magnesium oxide, aluminum oxide, and ceramic powder.
The HFTGB series of flexible synthetic mineral insulated fire-resistant cables enhances electrical and mechanical properties, while also improving chemical resistance. This solves the problem of rigid fire-resistant cables (BTTZ) easily absorbing moisture, which can affect their insulation performance. It also reduces electrical failures caused by the large number of joints required during installation.
③ Flexibility
It can be continuously wound onto a cable drum during production, allowing for smooth, kink-free unwinding during installation.
It is truly flexible, with a structure similar to that of ordinary cables and the same flexibility.
The cable's conductor utilizes sophisticated twisting and compression technology, ensuring a smooth, rounded conductor while also enhancing its flexibility.
The insulation material is a flexible synthetic mineral material with comparable flexibility to rubber.
The threaded outer sheath is made of non-magnetic stainless steel, ensuring the cable's bending properties.
Bend Radius Compliant with National Standards
Cable Outer Diameter D (mm) Power Cable Bend Radius Specified in GB/T12706 HFTGB Series Fire-Resistant Cables
≤20 15D 12D 7D
≤30 15D 12D 7D
≤40 15D 12D 7D
≤50 15D 12D 7D
≤60 15D 12D 7D
≤70 15D 12D 7D
④ Connectorless Cables
HFTGB series fire-resistant cables can be supplied according to customer-specified lengths and core counts. Whether single-core or multi-core, their lengths can meet power supply requirements.
Manufacturing Length Comparison with BTTZ Cables
Cable Specifications HFTGB (m) BTTZ (m) Cable Specifications HFTGB (m) BTTZ (m)
1*10 2000+ 480 3*4 1000+ 235
1*95 1500+ 145 3*10 1500+ 130
1*240 1500+ 56 3*25 1500+ 85
2*4 1000+ 250 4*4 1000+ 190
2*10 1500+ 150 4*10 1500+ 115
2*25 1500+ 90 4*25 1500+ 98
⑤ More environmentally friendly
The HFTGB series has passed testing by the National Fireproof Building Materials Supervision and Inspection Center. Tested data demonstrates that its performance exceeds the national flame-retardant Class A low-smoke halogen-free cable requirements.
Comparison of China Ministry of Public Security standards and measured values:
Project GA306 Standard Requirements VS Burning Test Measured Values
pH ≥4.3 5.5
Conductivity μs/mm ≤10.0 0.7
Smoke Density (Minimum Light Transmittance) % ≥80 93
⑥ Greater Current-Carrying Capacity
The HFTGB series fire-resistant cables have a current-carrying capacity far exceeding that of ordinary cables, and the stainless steel threaded sheath facilitates heat dissipation, enabling them to transmit higher currents.
⑦ Superior Overload Resistance
The insulation layer of the HFTGB series fire-resistant cables quickly forms a rigid shell when exposed to high temperatures. Even when subjected to overload, overload, or short-circuit currents that cause the conductor to melt (1083°C), they prevent short circuits and fires. Even if the conductor breaks, the resulting copper melt will not escape, eliminating electrical failures caused by overloads and preventing fires.
⑧ Superior Protection
The HFTGB series fire-resistant cable sheath is made of non-magnetic stainless steel with a threaded shape, ensuring scratch resistance during installation and withstanding the impact of burnt debris and other heavy objects during a fire. It is also resistant to termites and rats.
⑨ Manufacturing Scope
The HFTGB series fire-resistant cables feature multi-core conductors with a maximum cross-section of 300mm², meeting various building wiring and cable specifications.
⑩ Installation and Laying
The HFTGB series fire-resistant cables are connector-free and lightweight, allowing for installation similar to conventional cables. No special tools are required for bending, wiring, or stripping during installation. Installation can be performed using hangers or support arms, eliminating the need for expensive installation accessories and ensuring maintenance-free operation.
