Porcelain wall busing
Porcelain wall bushing (CWWL/CWB series) are precision-engineered components designed for safe conductor penetration through walls, transformer tanks, or switchgear enclosures in electrical substations. Utilizing high-strength glazed porcelain as the primary insulation, these bushings deliver exceptional dielectric performance, mechanical resilience, and long-term reliability under extreme environmental and electrical transients.
Key technical features
Robust Porcelain Insulation
Superior UV, pollution, and humidity resistance with extended creepage design.
Self-cleaning surface properties for minimal maintenance in harsh environments.
High Mechanical Strength
Bending failure loads up to 16 kN (model-dependent) to withstand seismic forces.
Rigid construction prevents deformation during operation.
Electrical Performance
Short-circuit withstand: Up to 80 kA for 5 seconds (CWWL-10/4000).
BIL (Basic Lightning Impulse Level): Up to 195 kV (35 kV class).
Power frequency withstand: Dual-rated (dry/wet) per IEC 60060.
Adaptable Design
Hermetic sealing flanges for diverse applications.
Copper conductors (400–4000 A) with tin-silver plating.
Technical specifications
| Porcelain wall busing | ||||||||
|---|---|---|---|---|---|---|---|---|
| Type | Rated voltage (kV) | Rated current (A) | 5 seconds of short current (≮kA) | power frequency voltage (≮kV) | BIL(≮kV) | Bending failure load (≮kN) | ||
| Dry withstand voltage | Dry withstand voltage | breakdown | ||||||
| CWWL-10/2000 | 10 | 2000 | 40 | 47 | 30 | 75 | 80 | 8 |
| CWWL-10/3150 | 10 | 3150 | 60 | 47 | 30 | 75 | 80 | 8 |
| CWWL-10/4000 | 10 | 4000 | 80 | 47 | 30 | 75 | 80 | 16 |
| CWWL-20/2000 | 20 | 2000 | 40 | 75 | 50 | 120 | 125 | 8 |
| CWWL-20/3150 | 20 | 3150 | 60 | 75 | 50 | 120 | 125 | 8 |
| CWB-10/400 | 10 | 400 | 7.2 | 47 | 34 | 75 | 80 | 7.5 |
| CWB-10/600 | 10 | 600 | 12 | 47 | 34 | 75 | 80 | 7.5 |
| CWB-10/1000 | 10 | 1000 | 20 | 47 | 34 | 75 | 80 | 7.5 |
| CWB-10/1500 | 10 | 1500 | 30 | 47 | 34 | 75 | 80 | 7.5 |
| CWB-35/400 | 35 | 400 | 7.2 | 110 | 80 | 176 | 195 | 7.5 |
| CWB-35/600 | 35 | 600 | 12 | 110 | 80 | 176 | 195 | 7.5 |
| CWB-35/1000 | 35 | 1000 | 20 | 110 | 80 | 176 | 195 | 7.5 |
| CWB-35/1500 | 35 | 1500 | 30 | 110 | 80 | 176 | 195 | 7.5 |
| CWWB-35/2000-3 | 35 | 2000 | 40 | 110 | 80 | 176 | 195 | 7.5 |
| CWWB2-35/2000-3 | 35 | 2000 | 40 | 110 | 80 | 176 | 195 | 7.5 |
Standards compliance
IEC 60137 (Insulated Bushings)
IEEE C57.19.00 (General Requirements)
GB/T 4109 (High-Voltage Porcelain Bushings)
Conclusion
Porcelain wall bushings (CWWL/CWB series) set the benchmark for critical HV penetrations where failure is not an option. With unmatched electrical endurance (195 kV BIL), seismic resilience (16 kN load), and fire safety (Class A1), they ensure zero-compromise reliability in substations, industrial plants, and renewable infrastructure. Engineered for a 40+ year lifecycle with minimal maintenance, these bushings deliver operational excellence across the power ecosystem.