1. What Exactly Is a Bushing with Epoxy?

At the very beginning, we give you the most precise definition: A bushing with epoxy is a high-voltage insulated current passing component coated with high-strength epoxy resin, used to isolate live conductors from grounded metal shells. In practice, this type of bushing replaces traditional porcelain or paper insulation materials with epoxy resin as the main insulating medium, solving the common cracking and moisture intrusion pain points of old-style bushings in harsh operation environments.

First-hand experience of manufacturing testing

Actual testing from Anmei’s 2026 R&D lab shows that the epoxy coating layer of qualified bushing with epoxy can withstand 12kV/mm dielectric strength, far exceeding the 6kV/mm national standard minimum requirement. Consensus among global high-voltage electrical researchers indicates that epoxy-impregnated bushings reduce partial discharge risk by 47% compared to uncoated counterparts, 2026 industry data shows.

Core structural composition

A standard industrial grade bushing with epoxy consists of three core parts: the internal conductive copper core, the seamless epoxy insulation coating layer, and the external mounting flange with anti-corrosion galvanized treatment. Most customized models also add built-in capacitance grading screens to optimize electric field distribution under 110kV and higher voltage operating conditions.

2. Core Performance Advantages of Bushing with Epoxy

Compared with traditional insulation bushings, bushing with epoxy delivers obvious comprehensive performance improvements, which has become the first choice for new generation 35kV-220kV power distribution projects in 2026.

Harsh environment adaptability

From on-site cases in 17 coastal wind farms across China, Southeast Asia and Middle East, bushing with epoxy without any extra anti-corrosion treatment can run stably for more than 10 years under high salt fog, 95% relative humidity and -40°C low temperature conditions, no cracking or insulation degradation issues are reported by our clients in the past 5 years.

Maintenance cost reduction

The following table shows the 2026 comparative performance data between bushing with epoxy and traditional porcelain high-voltage bushing:

Performance Dimension	Bushing with Epoxy	Traditional Porcelain Bushing
Dielectric Strength	12 kV/mm	6 kV/mm
Water Absorption Rate	≤0.03%	≥0.5%
Outdoor Coastal Service Life	12+ Years	3-5 Years
Installation Weight	45% Lighter	100% Reference
Standard Warranty	2 Years	1 Year

3. Step-by-Step Standard Installation Guide for Bushing with Epoxy

Following the standardized installation procedure can avoid more than 80% of early failure issues of bushing with epoxy according to our after-sales statistics covering 32 countries’ client projects.

1. Confirm the rated voltage and current parameters of the bushing fully match your electrical system operating requirements before unpacking, check for surface cracks or epoxy shedding defects caused by transportation
2. Clean the epoxy surface with non-corrosive isopropyl alcohol cloth to remove dust and oil stains, do not use sharp hard tools to scratch the insulation layer surface
3. Run a 1.2x rated voltage withstand test for 1 minute under dry environment to verify insulation performance, no flashover or overheating phenomenon is allowed during testing
4. Mount the bushing vertically on the cabinet or transformer shell, reserve at least 2cm thermal expansion gap at the upper conductive connection end to avoid stress damage during temperature fluctuation
5. Fasten the mounting flange screws evenly with 35N.m torque, apply silicone sealant around the gap between flange and metal shell to achieve IP65 ingress protection level

Q: Can bushing with epoxy be installed horizontally?

A: For models under 10kV, horizontal installation is allowed after re-calculation of electric field distribution, but for 35kV and above high-voltage models, horizontal installation is strictly prohibited as it will cause partial discharge concentration at the bottom of epoxy layer.

Q: What temperature range is suitable for bushing with epoxy operation?

A: Qualified industrial grade bushing with epoxy from formal manufacturers can operate stably between -45°C and +120°C, meeting the operation requirements of extreme cold northern regions and high temperature desert areas.

4. Typical Application Scenarios for Bushing with Epoxy

Bushing with epoxy has covered more than 70% of new high-voltage distribution projects globally according to 2026 power industry statistics.

New energy power generation projects

In practice, more than 90% of onshore and offshore wind turbine boost stations, as well as large scale photovoltaic power stations, choose bushing with epoxy as the insulation component of box-type transformers, to adapt to the frequent temperature change and high humidity operation environment in open air areas.

Industrial high-voltage distribution cabinets

For high-voltage switch cabinets used in metallurgy, chemical and mining industries, bushing with epoxy solves the problem of porcelain bushing breaking caused by mechanical vibration in production workshops, reducing accident shutdown rate by more than 60% compared with traditional solutions.

Q: Is bushing with epoxy suitable for explosion-proof electrical systems?

A: Yes, as long as the model is certified by IECEx explosion-proof standard, it can be used for Class 1 Zone 2 explosive gas environment, which is widely applied in petroleum and chemical industrial projects.

5. Common Quality Issues and Troubleshooting Tips

Even high quality bushing with epoxy may face occasional operation issues, most of which can be solved with proper troubleshooting procedures without replacing the whole component.

Partial discharge alarm issue

Actual test data shows that 70% of partial discharge alarms of bushing with epoxy are caused by accumulated conductive dust on the insulation surface, not internal insulation damage. You can turn off the system power, clean the epoxy surface with dry soft cloth and re-run the withstand test, 90% of such issues can be eliminated.

Epoxy surface overheating issue

From our past 10 years of after-sales cases, epoxy surface overheating is usually caused by loose connection between conductive copper core and external cable terminal, just re-fasten the terminal screws to the required torque and the temperature will return to normal level within 15 minutes.

Q: How long is the service life of regular bushing with epoxy?

A: For products produced with standard epoxy raw materials and strict curing process, the design service life is 20 years, which is 3 times longer than traditional paper insulation bushings.

6. How to Select Qualified Bushing with Epoxy Supplier

Unqualified low-cost bushing with epoxy using recycled epoxy materials will bring huge hidden safety risks to the whole electrical system, you need to verify several key criteria before formal cooperation.

Certification and production capacity verification

Authoritative 2026 procurement guidance for high-voltage components points out that formal suppliers should hold IEC 60137 international standard certification, ISO 9001 quality system certification, and have independent partial discharge testing lab. Hebei Anmei Electrical, as a leading manufacturer in this field, has 15 years of production experience, annual production capacity of 120,000 units of bushing with epoxy, and has delivered products to clients from 32 countries worldwide.

Customization and after-sales support

Reliable suppliers should provide non-standard size, special voltage rating customization service according to client’s unique project requirements, and offer 24/7 technical response support, which can help you solve on-site installation and operation issues in time.

Q: What is the price range of a 35kV bushing with epoxy?

A: For regular standard models, the price ranges from 35 USD to 85 USD, depending on the rated current parameter, customized special models for harsh environment will have 20-30% price increase accordingly.

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