Polysulfide Rubber Sealing For High-performance Epoxy Resin Bushing Production
Efficient end sealing of an epoxy bushing is vital for dielectric reliability. This process utilizes polysulfide rubber coating on metal conductors to mitigate thermal expansion stress and ensure a hermetic seal within the epoxy resin cast bushing assembly.
How to Seal Metal Conductors in Epoxy Resin Bushing Casting
To ensure a high-quality seal, start by degreasing and sandblasting the metal conductor. Apply a uniform polysulfide rubber layer to the interface zones. This elastomer coating acts as a flexible buffer, preventing delamination and moisture ingress during the curing cycle of the epoxy resin bushing. It maintains structural integrity despite the different expansion rates of metal and resin.
Technical Advantages of Polysulfide Elastomers
Polysulfide rubber is the industry standard for sealing because it remains stable under high thermal loads. It prevents partial discharge by eliminating micro-gaps at the conductor-resin interface.
Performance Data for Sealing Materials
| Property | Value | Unit |
|---|---|---|
| Thermal Range | -40 to +120 | °C |
| Hardness | 35 - 45 | Shore A |
| Elongation | >250 | % |
| Adhesion | 2.5 | MPa |
Quality Standards and Defect Prevention
Successful production of an epoxy resin cast bushing requires strict process control. Precision in coating thickness is essential: layers that are too thin fail to absorb stress, while excessive thickness affects dimensional accuracy.
Key Maintenance and Quality Tips
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Degassing: Vacuum degas the polysulfide compound to eliminate internal voids.
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Surface Prep: Ensure primer compatibility to maximize adhesion to the conductor.
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Environment: Maintain humidity below 65% for optimal chemical cross-linking.
By refining these sealing steps, technical teams can ensure the long-term operational safety of the epoxy resin bushing in high-voltage environments.
