In the realm of high-voltage transmission, the Ctv 255 Isolator En Verre U70B represents the pinnacle of material science and mechanical engineering. As power grids expand across continents, the demand for reliable insulation that can withstand both electrical stress and mechanical loads has never been higher.
Unlike traditional porcelain, toughened glass insulators like the U70B (70kN rating) offer a unique "fail-safe" property. When a glass insulator fails, the shell shatters into small granules, making the fault immediately visible to maintenance crews during helicopter or drone inspections. This Information Gain in grid maintenance significantly reduces downtime and operational costs.
Mechanical Strength Rating
Jiangxi QOCI Electric Co. Ltd, founded in 2002, epitomizes the "Factory 4.0" movement in China. With a registered capital of 508 million Yuan and a 70,000 m² state-of-the-art facility, our production line integrates total oxygen kilns and automated forming presses.
Utilities in Europe, Africa, and Southeast Asia are increasingly shifting toward glass insulators for their superior performance in coastal and industrial areas. The CTV 255 series is specifically designed for international tenders where durability and long-term TCO (Total Cost of Ownership) are the primary metrics.
From the IEEE PES T&D Conference to Enlit Africa, the industry consensus is clear: Grid Hardening starts with the insulator.
The U70B glass isolator provides a standardized 255mm diameter and 146mm spacing. Its smooth surface prevents the accumulation of pollutants, while the toughening process ensures the internal residual stress remains stable for decades under AC and DC loads.
Founded in December 2002, Jiangxi QOCI Electric Co. Ltd is located in the Industrial Park of Luxi County, Jiangxi Province. We serve the world-class power grid with dedication and actively participate in the construction of green energy infrastructure globally.
Designed for Specific Environmental Challenges
Shallow and well-spaced small ribs, effectively self-cleaning by wind or rain. Exceeds IEC 60305 leakage distance requirements.
Characterized by long and widely-spaced under-ribs to avoid arc bridging. Ideal for salt fog coastal areas.
Absence of under-ribs to avoid solid pollution deposits like dust and sand. Perfect for desert environments.
Room Temperature Vulcanization (RTV) coating provides hydrophobic properties, reducing maintenance in extreme pollution.
Optimized for UHV lines with three layers of umbrella discs for maximum pollution flashover resistance.
Our products are primarily high-strength glass insulators used in low voltage, high voltage, ultra-high voltage, and extra-high voltage AC (DC) electric transmission lines. We ensure reliability against icing, high altitude, heavy pollution, earthquakes, and typhoons.
Forming Press
Oxygen Kiln
HV Testing
Raw Materials
Quality Management Certified: ISO 9001, ISO 14001, OHSAS 18001
Expert insights into U70B/CTV 255 selection and maintenance
QOCI Electric officially confirmed its attendance at major global summits like the Iraq Energy Exhibition and IEEE PES T&D. As the energy transition accelerates, the demand for renewable integration requires robust transmission backbones supported by U100 and U120 series insulators.
Published: May 10, 2026
Withstanding extreme environments like typhoons and earthquakes, China's insulator technology is now a mature portfolio preferred by global EPC contractors.
