Epoxy Resin Sleeve Process Parameter Comparison Table: Complete List Of Temperature/time/feed Rate/thickness
In the field of electrical insulation, mastering core processes is essential for every engineer. To help everyone intuitively understand the production process, we have compiled a list of key control points in the processing of epoxy bushing, aiming to improve the insulation performance and mechanical strength of the product through standardized parameter management.
Epoxy Resin Sleeve Process Parameter Reference Table: Complete List of Temperature/Time/Feed Rate/Thickness
In actual production, the ambient humidity usually needs to be maintained below 40% to prevent moisture from affecting the resin crosslinking reaction. The following are references for core parameters for standard APG (Pressure Gel) or vacuum casting processes:
| Process | Temperature range (°C) | Duration (min) | Feed/Pressure/Speed | Thickness control/target |
| Mold preheating | 80 - 120 | 60 - 120 | Static heating | Maintain surface temperature difference < 5°C |
| Mixing ingredients | 40 - 60 | 30 - 90 | Vacuum degree < 100Pa | Viscosity 3000 - 8000 mPa·s |
| Injection feeding | Mold temperature lower limit | 5 - 15 | Feed pressure 0.2 - 0.4 MPa | Until the mold is full |
| Initial curing | 130 - 145 | 15 - 40 | Pressure maintained at 0.3 MPa | gel formation |
| Post-baking | 140 - 160 | 480 - 720 | Natural convection | The final insulation layer thickness meets the standard. |
Detailed Breakdown of the Process
This comparison table will be slightly adjusted for different voltage levels of epoxy resin bushing production. Specific details are as follows:
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Temperature Control: The temperature rise curve must adopt a stepped design. Too rapid an initial temperature rise can lead to internal stress buildup, inducing microcracks. Generally, a temperature rise of no more than 20°C per hour is not recommended.
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Time Management: The vacuuming time directly determines the bubble content. If the time is reduced, the partial discharge charge (PD) will often exceed the limit.
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Feed Rate and Pressure: Too fast a feed rate can easily trap air, while too slow a feed rate will cause the resin to gel prematurely in the runner, resulting in incomplete injection molding.
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Thickness and Dimensions: The thickness of the insulation layer not only determines the withstand voltage rating but also affects heat dissipation. Calculations should be made using precision molds and feed rate, with an error controlled within ±0.5mm.
Conversational Insights from the Production Site
Those who have worked in this industry for a long time know that data on paper is static; on-site operation requires flexibility. For example, the cooling rate of the mold differs significantly between summer and winter. Therefore, it's crucial to monitor the temperature controller closely and not rigidly adhere to the fixed times on the chart.
During pouring, the sound from the ejector nozzle indicates whether air bubbles have been completely removed. If "orange peel texture" appears on the surface of epoxy resin cast bushing, it is mostly because the release agent was sprayed too thickly or the mold temperature was uneven. Mastering this checklist adds an extra layer of safety to the otherwise tedious process, ensuring product quality.
