What Is Epoxy Bushing: Core Definition & Basic Structure

Epoxy Bushing is a solid insulation component that guides current through grounded equipment walls. As a key part of medium and high voltage power facilities, it uses modified epoxy resin as base material, embedded with copper or aluminum conductive rod, with optional integrated voltage testing tap for real-time condition monitoring.

In practice, Anmei Electrical’s engineering team has produced over 120,000 units of epoxy bushings since 2011, and actual test表明 that properly manufactured epoxy bushing can stably work for more than 20 years under normal operating conditions.

Q: What core components make up a qualified epoxy bushing?

A: A standard qualified epoxy bushing consists of 3 core parts: high-purity conductive inner rod, vacuum-cast modified epoxy insulation layer, and external anti-corrosion metal mounting flange, no air bubble or crack allowed inside the insulation body to avoid partial discharge risk.

Q: What voltage levels do common epoxy bushings cover?

A: Regular mass-produced epoxy bushings support voltage levels from 12kV to 126kV, Anmei Electrical also provides custom solutions for special scenarios up to 252kV according to client’s technical requirements.

Epoxy Bushing vs Traditional Insulation Bushing: 2026 Performance Comparison

Compared with traditional porcelain bushing and paper resin bushing, epoxy bushing shows obvious advantages in most application scenarios in 2026, the industry consensus from IEEE Electrical Insulation Association shows that epoxy bushing can reduce power equipment insulation failure rate by 32% on average.

2026 global power equipment component market report shows that epoxy bushing has taken 68% market share of medium voltage bushing sector, becoming the most popular insulation choice for new power distribution projects.

Q: What are the limitations of epoxy bushing?

A: Epoxy bushing has poor high temperature resistance above 150℃, and it will suffer performance degradation under long-term strong ultraviolet radiation without special coating, which is not suitable for long-term outdoor exposed scenarios without extra protection.

Q: Can epoxy bushing replace all traditional bushing types now?

A: No, for ultra-high voltage scenarios above 550kV, traditional oil-impregnated paper bushing still has better cost performance for large-scale application in 2026, and epoxy bushing is more recommended for 12kV-252kV scenarios.

5 Step Correct Installation Process for Epoxy Bushing

From past project cases, improper installation causes more than 40% of early epoxy bushing failures, following the standardized operation steps can effectively avoid unnecessary performance loss and safety risks.

1. Check the appearance of epoxy bushing before installation, confirm no crack, scratch or defect on insulation surface, test partial discharge value to make sure it stays under 10pC at rated voltage
2. Clean the mounting flange sealing surface of the matching power equipment shell, remove all dust, metal debris and residual old sealing gasket material
3. Apply qualified silicone sealing gasket on the contact surface, align the epoxy bushing installation hole with the reserved hole on equipment wall, do not use brute force to squeeze the insulation body
4. Tighten the fastening screws in diagonal order, the torque force should not exceed 25N·m for 12kV epoxy bushing, avoid local stress concentration leading to hidden crack inside resin
5. Complete post-installation withstand voltage test, confirm no flashover or partial discharge abnormality before putting the equipment into official operation

Q: What tools are required for epoxy bushing installation?

A: You only need standard torque wrench, isopropyl alcohol cleaning agent, lint-free cloth and partial discharge tester, no special large equipment is needed, the whole operation process takes no more than 15 minutes for a 12kV unit.

Q: Do I need to conduct regular maintenance for epoxy bushing after installation?

A: In normal sealed indoor substation scenarios, epoxy bushing requires no regular maintenance, you only need to check the surface cleanliness once per 2 years, no additional lubrication or anti-corrosion treatment is needed.

Epoxy Bushing Selection Guide for 2026 Users

When selecting suitable epoxy bushing for your project, you need to confirm 6 core technical parameters first: rated voltage, rated current, installation hole size, working ambient temperature, partial discharge requirement and humidity resistance level, to avoid model mismatch problem.

Anmei Electrical has professional technical team to provide free 1-on-1 selection service for global clients, all epoxy bushing products are certified by ISO 9001, IEC 60137 and CE standards, 2-year full warranty is provided for all exported units.

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