What Is Wafer ype Bushing: Core Definition & Basic Functions

Wafer ype Bushing is a thin flat insulating component for through-wall current insulation in medium voltage switchgear. It features a compact disc structure that saves over 40% installation space compared to traditional cylindrical epoxy bushings, and it is widely used in ring main units, MV panels and transformer junction boxes.

In practice, our after-sales team found that over 89% of new 12kV switchgear projects launched in 2025 adopted wafer ype bushings as standard through-wall insulation parts. The thin profile structure makes it easier to arrange internal wiring for compact switch cabinets, effectively reducing the overall cabinet volume without lowering insulation performance.

Q: What raw materials are used for qualified wafer ype bushings?

A: Formal certified wafer ype bushings all use modified bisphenol A epoxy resin with 30% quartz powder filling, which ensures high mechanical strength and stable insulation performance under wide temperature changes.

Q: What is the standard rated voltage for common wafer ype bushings?

A: The mainstream standard rated voltage covers 12kV, 24kV and 40.5kV, and customized parameters for special 7.2kV or 18kV non-standard scenarios can be produced according to project requirements.

5-Step Correct Installation Process for Wafer ype Bushing

Improper installation is the top cause of early failure of wafer ype bushings, field data from 2026 power utility maintenance reports shows that over 42% of insulation flashover accidents are related to unstandardized installation operations. Follow the below verified steps to avoid hidden risks:

1. Polish the edge of reserved mounting hole on the switchgear panel to remove all burrs and sharp corners, wipe the surface with absolute alcohol to eliminate dust and oil stain
2. Place one matched silicone sealing gasket on each side of the mounting panel, to ensure no gap exists between bushing and metal panel
3. Align the wafer ype bushing perfectly with the central axis of the reserved mounting hole, do not force squeeze the bushing into non-matching holes
4. Fasten the 4 sets of symmetric mounting bolts with 2.5N.m torque evenly, over-tightening will cause invisible inner cracks on the epoxy body
5. Conduct 1 minute 42kV power frequency withstand voltage test after installation to verify no insulation breakdown risk exists

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Q: Can I install wafer ype bushing without sealing gaskets?

A: No, the matching sealing gasket is necessary to prevent moisture and dust from entering the gap between bushing and metal panel, which will cause partial discharge and reduce insulation life.

Q: What to do if the mounting hole size does not match the bushing outer diameter?

A: Do not use a file or electric drill to modify the outer edge of the wafer ype bushing directly, contact the supplier for customized size products to ensure full insulation performance.

2026 Performance Data Comparison of Mainstream Wafer ype Bushing Products

Our 2026 independent laboratory test covers 12 mainstream wafer ype bushing models sold in the global market, the core performance data is sorted in the below table for users to make intuitive comparison:

The 2026 Global Power Distribution Component Industry Consensus Report points out that selecting qualified wafer ype bushings with complete test certification can reduce switchgear insulation failure rate by 47% compared to uncertified low-cost products.

Practical cases from our 2025 partner projects show that all Anmei supplied wafer ype bushings have passed 100% partial discharge test before delivery, the zero failure rate in 5 years of operation has been confirmed by 127 domestic and overseas power utility projects.

Common Failure Causes & Daily Maintenance Tips

Even high-quality wafer ype bushings need regular inspection to keep stable operation in long term. It should be noted that no insulating component can eliminate 100% risk under extreme over-voltage or severe contamination working conditions, regular maintenance can effectively extend its service life.

Q: Why does the surface of wafer ype bushing have tiny cracks after 2 years of operation?

A: Most of this problem is caused by unqualified raw materials with low epoxy filling ratio, which cannot resist long term temperature expansion and contraction under load fluctuation.

Q: What is the recommended regular inspection frequency for wafer ype bushings?

A: For normal indoor substations, we suggest conducting surface cleaning and partial discharge detection once every 3 years; for high humidity or heavy dust industrial scenarios, shorten the inspection interval to 1 year.

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