I. WTTEZ Cable Structure: 1. Stranded conductor; 2. Inorganic composite insulation; 3. Inorganic composite expansion filler; 4. Corrugated copper tube sheath; 5. Low-smoke, halogen-free outer sheath.
WTTEZ Cable Performance Features:
① Excellent fire resistance and fire resistance. To ensure the cable can function properly in flames, and maintain structural stability under fire conditions, a fire-resistant and intumescent sheath is incorporated into the cable design. This sheath expands under fire conditions, further stabilizing the cable insulation. This makes the cable a truly fire-resistant cable, capable of maintaining power supply even in fires near the melting point of copper.
② Long continuous production lengths, large cross-sections, and excellent bending properties. ● Long continuous production lengths. The cable's production length is not limited by processing technology or production equipment, fully meeting power supply requirements. Production lengths up to 2,000 meters are possible. ● Large Cross-Section: This cable's conductor is constructed from multiple strands of twisted wire, significantly increasing its flexibility. Furthermore, twisted conductors offer excellent production continuity and long processing lengths, reducing the number of joints. Large-cross-section single-core cables can reach cross-sections up to 800mm². ● Excellent Bendability: The copper sheath is corrugated, increasing the cable's flexibility and providing excellent bending performance.
③ High Current Carrying Capacity and Waterproofing: ● High Current Carrying Capacity: This cable can withstand a normal conductor temperature of 180°C. Its current carrying capacity far exceeds that of conventional cables with the same conductor cross-section. ● Waterproof: This cable is protected by a sealed non-magnetic metal tube, offering superior waterproofing.
④ Explosion-Proof, Corrosion-Resistant, and Electromagnetic Interference-Resistant: ● Explosion-Proof: This cable utilizes a copper sheath. After combustion, the filler layer expands and compacts the core, preventing flammable gases and flames from reaching connected electrical equipment. This makes the cable explosion-proof. ●Excellent corrosion resistance: Copper possesses excellent corrosion resistance, so no additional protection is required under normal use. However, in special environments, such as those with strong corrosion to copper, corrosion resistance can be achieved simply by adding a low-smoke, halogen-free outer sheath to the cable. ●No electromagnetic interference: Because this cable is shielded by a copper sheath, it will not interfere with signal and control lines when installed alongside other cables.
II. Technical Comparison of WTTEZ Inorganic Composite Insulated Fire-Resistant Cable and BTTZ Mineral Insulated Cable Items: High Flame-Retardant Fire-Resistant Cable Mineral Insulated Cable (BTTZ) Inorganic Composite Mineral Insulated Cable (WTTEZ) Combustion Performance: Flame Retardant (Class A): Non-flammable Non-flammable Smoke: Dense smoke Smokeless Smokeless Halogen: High halogen: Halogen-free Halogen-free Toxicity: Highly toxic Non-toxic Non-toxic Fire Resistance: Meets Class B: 750°C-800°C (90 minutes); Exceeds Class A: 950°C-1000°C (3 hours); Exceeds Class A: 950°C-1000°C (5 hours); Spray Test: Failed Passed Vibration Test: Failed Passed Production Length Requirements: Unlimited length, each section not exceeding 50 meters. Length is unlimited, no joints required. Laying Requirements: Unlimited Fixed, non-removable Unlimited
III. Other Information: WTTEZ offers superior fire resistance, long production lengths, and excellent bending properties, making it a viable alternative to BTTZ cables. WTTEZ cables offer superior high-temperature and fire resistance, excellent bending properties, advanced manufacturing technology, and simple installation. They offer both electrical insulation and cable structural stability in high-temperature fire environments, surpassing the performance of traditional mineral-insulated cables. Furthermore, WTTEZ cables feature advanced manufacturing technology and simple installation, significantly reducing overall costs compared to mineral-insulated cables (BTTZ) under comparable conditions.
BTTZ Mineral Insulated Cable Structure and Performance Characteristics
1. BTTZ Cable Structure: 1. Solid conductor; 2. Magnesium oxide mineral insulation; 3. Copper sheath
2. BTTZ Cable Performance Characteristics: BTTZ cables offer the following advantages: Due to their all-inorganic construction, they are non-combustible, possess excellent waterproof and radially waterproof properties.
The disadvantages of BTTZ cable are:
① First, it is not suitable for mobile applications. Once the copper tube is damaged, the insulation performance will rapidly deteriorate, and the insulation performance will drop sharply at high temperatures. Therefore, it is not suitable for large-scale use in projects. ② Second, because the magnesium oxide insulation of this cable is easily hygroscopic, longitudinal moisture-proofing of the cable and protection against damage to the metal sheath are particularly important. Using sealant at the ends will seriously reduce the service life. ③ Third, the manufacturing process also limits the cable length, resulting in an increased number of joints, making waterproofing of the joints difficult. Water ingress into the joints often results in substandard insulation resistance. YTTW Mineral Insulated Cable Structure and Performance Characteristics 1. YTTW Cable Structure ① Copper conductor ② Inorganic (mineral) insulation tape that is resistant to high temperatures (1375°C) and non-flammable ③ Outer copper sheath
2. YTTW Cable Performance Characteristics
1 Advantage: It is a metal-sheathed inorganic mineral insulated cable. It is a flexible fire-resistant cable.
1. Fire Resistance: The two materials used in mineral insulated cables, copper and magnesium oxide, are inorganic substances. This cable does not burn or support combustion and can continue to operate even in the presence of flames. The copper sheath melts at 1083°C, while the magnesium oxide insulation solidifies at 2800°C.
2. High Operating Temperature: Mineral insulated cables can withstand continuous operating temperatures up to 250°C. However, in emergency situations, the cables can continue to operate for a short period at temperatures close to the copper sheath's melting point.
3. Long Life: The inorganic materials used in mineral insulated cables ensure the cables' stability, long life, and fire resistance. Disadvantages: YTTW cables utilize a copper sheath, significantly increasing production costs. Cables with larger cross-sections are relatively rigid and lack flexibility, making larger cross-sections (greater than 630mm²) unavailable and unable to meet the high current requirements of the system. The cable's copper conduit is longitudinally wrapped and continuously welded, making it prone to detachment. A cable explosion occurred during use in the China Pavilion at the Shanghai World Expo due to the bending radius. The China Pavilion has been severely damaged by the current issues, and the risks are high, so the future remains uncertain.
Performance Comparison of YTTW and BTTZ Cables
1. YTTW – Flexible fire-resistant cable; BTTZ – Rigid fire-resistant cable.
2. YTTW – Unlimited cable length; BTTZ – Limited by manufacturing process, conductor cross-sections are small and cable lengths are short.
3. YTTW – Meets the requirements of design and construction acceptance specifications; BTTZ – Difficult to meet the mandatory requirement of the "Power Engineering Cable Design Code" that "cable lines should not have joints in the middle," and the requirements of the "Civil Building Electrical Design Code" and the "Electrical Installation Engineering Cable Line Construction and Acceptance Code" that "intermediate joints should be avoided" and "cable joints should be reduced."
