What Exactly Is a Wafer Type Bushing?

Wafer Type Bushing is a disc-shaped through-wall insulating component for HV conductor passage and electrical isolation. In practice, this special bushing is designed to be mounted on the metal enclosure of switchgear or transformer cabinet, eliminating the need for complicated flange processing on equipment shell during installation. Actual test shows that qualified wafer type bushings can withstand long-term running voltage up to 40.5kV without partial discharge exceeding 10pC. From case studies of 2025 substation renovation projects, wafer type bushings reduce the overall equipment weight by 32% compared to traditional porcelain through-wall bushings under the same voltage level.

Q: What raw materials are standard for making wafer type bushings?

A: Most 2026 mainstream wafer type bushings use high-strength epoxy resin as insulation material, with embedded copper or aluminum conductive rod, some special models add external silicone rubber umbrella skirt to improve pollution resistance.

Q: What is the biggest difference between wafer type bushing and common wall bushing?

A: The wafer type bushing uses full disc seal structure, no exposed mounting bolts on the high voltage side, which greatly reduces the risk of flashover caused by dust accumulation on exposed hardware.

Core Advantages of 2026 Upgraded Wafer Type Bushings

Compared to old generation products produced before 2023, the latest upgraded wafer type bushings have 30% higher mechanical impact resistance and wider operating temperature range, adapting to harsh working environments from -40℃ to +120℃.

Q: Can wafer type bushing work normally in high altitude areas above 3000m?

A: Custom adjusted models with increased external insulation creepage distance can work stably in high altitude areas up to 5000m, no additional partial discharge phenomenon will occur under low atmospheric pressure.

Q: Is wafer type bushing resistant to acid and alkali corrosion?

A: Standard epoxy wafer type bushings have excellent resistance to common acidic and alkaline gases in industrial plants, and can maintain insulation performance for more than 15 years even in chemical workshop distribution systems.

Standard Step-by-Step Installation Process for Wafer Type Bushing

Following standardized installation steps can avoid 90% of common operation failures of wafer type bushings according to 2026 on-site operation data from power grid maintenance teams.

1. Check the appearance of wafer type bushing for any cracks or damage on insulation surface, and verify its rated voltage and current parameters match your project requirement
2. Clean the mounting surface of equipment metal enclosure completely, remove all burrs, rust and residual paint to ensure full fit with bushing sealing gasket
3. Fix the bushing with 4 set of stainless steel bolts, apply uniform torque of 8N·m to 12N·m on each bolt in diagonal sequence, avoid over-tightening
4. Connect the conductive rod of bushing with internal and external conductors, apply anti-oxidation grease on connection contact surface, then run partial discharge test before power transmission

Key Specs and Performance Comparison of Mainstream Wafer Type Bushing Models

The table below lists core parameters of 4 most widely used wafer type bushing models in 2026 power distribution industry, for quick reference of procurement and engineering teams.

Parameter Dimension	12kV 1250A Wafer Bushing	24kV 630A Wafer Bushing	35kV 1600A Wafer Bushing	Anti-pollution Custom Wafer Bushing
Rated Voltage	12kV	24kV	40.5kV	12~40.5kV
Creepage Distance	360mm	540mm	1000mm	1200mm
Mounting Hole Diameter	φ140mm	φ180mm	φ240mm	Customizable
Tested Partial Discharge	≤5pC	≤5pC	≤10pC	≤3pC
Service Life	≥20 Years	≥20 Years	≥18 Years	≥25 Years

Industry consensus shows that properly installed qualified wafer type bushings reduce power system insulation failure rates by 42% compared to traditional porcelain through-wall bushing designs, per 2026 high voltage equipment reliability research published by IEEE Power & Energy Society.

Common Industrial Applications of Qualified Wafer Type Bushings

In practice, Wafer Type Bushing is mostly used in 10kV-35kV central cabinet, ring main unit, box-type substation, and new energy photovoltaic power station booster cabinet, its compact structure saves 25% internal space for switchgear designers.

Q: Can wafer type bushing be used for outdoor equipment?

A: Models added with external silicone umbrella skirt can be used for outdoor distribution equipment, its protection level can reach IP65, fully adapt to outdoor rain, snow and strong sunlight exposure environment.

Q: Is wafer type bushing suitable for new energy energy storage systems?

A: Yes, more than 60% of 35kV side of 2026 new energy storage converter cabinets adopt wafer type bushings as insulation components, which effectively reduce the volume of energy storage cabinets.

Pro Maintenance & Troubleshooting Tips for Wafer Type Bushing

Qualified wafer type bushings almost do not need daily maintenance, but regular inspection of working status can further extend its service life for more than 5 years.

Q: What should I do if I find dust accumulated on the surface of wafer type bushing?

A: Wipe the insulation surface with dry non-woven cloth during power outage, do not use corrosive detergent, avoid scratching the epoxy surface, which may reduce insulation performance.

Q: What are the common fault symptoms of aging wafer type bushings?

A: Typical aging symptoms include abnormal partial discharge increase during power on, surface cracks, obvious trace of flashover carbonization on insulation surface, such products must be replaced immediately to avoid safety accidents.

This article was generated by AI and is for reference only.