Product Overview
The TG3-35Q/190×208×445 Wall-Throught Bushing is an epoxy resin insulating bushing designed for 35 kV high-voltage power systems. It is mainly used where conductive parts pass through walls, partitions, or other grounded structures, providing electrical insulation and mechanical support. It is widely used in substations, distribution stations, and high-voltage switchgear.
The product is manufactured through an integrated epoxy resin casting process. Its shed-profile surface effectively increases the creepage distance and improves pollution resistance, ensuring stable insulation performance in high-voltage environments.
Technical Specifications
| Parameter | Specification |
|---|---|
| Model | TG3-35Q/190×208×445 |
| Rated Voltage | 35 kV, with a maximum operating voltage of 40.5 kV |
| Rated Frequency | 15–60 Hz |
| Overall Dimensions | 190 × 208 × 445 mm |
| Insulating Material | Epoxy resin or silicone rubber composite insulation |
| Power-Frequency Dry Withstand Voltage | ≥95 kV for 1 minute, RMS |
| Lightning Impulse Withstand Voltage | ≥185 kV peak |
| Creepage Distance | ≥1,020 mm, meeting Pollution Level IV requirements |
| Flame-Retardant Rating | UL94 V-0 |
| Temperature Resistance | -40°C to +120°C |
| Mechanical Bending Strength | ≥8 kN |
| Product Certification | ISO 9001; CCC optional |
Product Features
Excellent Insulation Performance
- The integrated epoxy resin cast structure contains no internal air gaps and has low partial discharge, enabling long-term operation under high-voltage conditions.
- The multi-shed design significantly increases the creepage distance and effectively reduces the risk of pollution flashover and wet flashover.
High Mechanical Strength
- The square flange and main body are formed as an integrated structure, providing excellent resistance to bending and impact and allowing the product to withstand electrodynamic forces caused by busbar short circuits.
- The product offers strong weather resistance and is suitable for complex indoor and outdoor environments, with good resistance to cracking and ageing.
Pollution Resistance and Environmental Performance
- The smooth and dense surface provides good hydrophobic performance, making accumulated contamination easier to clean and allowing use in heavily polluted areas.
- The product contains no toxic or hazardous substances, complies with environmental requirements, and can be recycled.
Convenient Installation
- The standardized flange dimensions provide high compatibility with switchgear and wall openings, eliminating the need for additional machining.
- Compared with porcelain bushings, the product is approximately 40% lighter, reducing transportation and installation costs.
Safe and Reliable
- An integrated electric field shielding structure is available as an option to optimize electric field distribution and reduce localized overheating and discharge.
- The product provides excellent flame-retardant and arc-resistant performance, helping prevent the spread of electrical fires.
Applications
- Suitable for three-phase AC power systems with a rated voltage of 35 kV, a maximum operating voltage of 40.5 kV, and a frequency of 15–60 Hz.
- Typical applications include:
a. High-voltage distribution equipment in substations and distribution stations, used for busbars passing through walls or partitions.
b. Internal insulation and busbar connections in KYN61, withdrawable, and other high-voltage switchgear.
c. High-voltage distribution systems in power plants, industrial facilities, and mining enterprises, where the product serves as an insulating support for conductive components.
d. General and heavily polluted areas at altitudes of up to 3,000 m. Customized high-altitude versions are available.
Operating Conditions
Environmental Conditions
- Ambient temperature: -40°C to +40°C. Special temperature-resistant versions can be extended to -50°C to +120°C.
- Installation altitude: no more than 3,000 m. A reinforced high-altitude version is required for higher altitudes.
- Daily average relative humidity: no more than 95%.
- Monthly average relative humidity: no more than 90% at 25°C.
- The installation location should be free from severe vibration, impact, and explosion hazards.
- The standard product should be used in environments without corrosive or flammable gases or severe dust pollution. Special corrosion-resistant versions are available.
Electrical Conditions
- System rated voltage: 35 kV.
- Maximum operating voltage: 40.5 kV.
- Rated current: suitable for busbars rated from 630 A to 3,150 A. The appropriate model should be selected according to the required current rating.
- Short-circuit withstand capability: capable of withstanding the specified 4-second thermal withstand current and dynamic withstand current, depending on the selected model.
Installation Requirements
- Installation orientation: vertical or horizontal. The flange surface must fit closely against the grounded mounting surface.
- Mounting opening: must strictly match the 190 × 208 mm flange dimensions to ensure effective sealing and even load distribution.
- Conductor connection: when connecting to a busbar or cable, ensure good electrical contact to prevent localized overheating.
- Protection level: IP4X for indoor models. Outdoor models can be upgraded to IP5X when used with suitable sealing components.
Precautions
- Before installation, inspect the product to ensure that there are no cracks, damage, bubbles, or obvious scratches and that all sheds are complete.
- Avoid impact and dropping during handling and installation to prevent damage to the insulating layer.
- Do not apply paint or cover the bushing surface with insulating tape, as this may affect creepage performance.
- Conduct regular inspections of surface contamination, shed ageing, and loose flange connections, and perform cleaning and maintenance as required.
- For heavily polluted areas, a pollution-resistant model with an increased creepage distance is recommended.
Selection and Customization
- Models with different mounting dimensions, creepage distances, and current ratings can be customized according to actual requirements.
- Optional configurations include an integrated electric field shielding layer, anti-corrosion coating, and reinforced high-altitude design.
- Product selection should take the system voltage, rated current, environmental pollution level, and installation method into consideration.
