Long-lasting Sealing Solution For Epoxy Resin Sleeves: Practical Application Of Coating Process For Exposed Areas
In the manufacturing process of power equipment, the post-casting treatment of epoxy resin bushings often determines the insulation reliability of the finished product. After the main body of the product is cast and demolded, exposed areas such as metal inserts or flanges are highly susceptible to moisture intrusion. This article shares a sealant coating technology for exposed interfaces to help technicians improve the surface protection level of the product.
Optimizing the sealing logic of the epoxy resin sleeve interface
High performance of epoxy bushing manufacturer depends not only on the density of the internal castable, but also on the physical shielding at its interface with external components. Due to the difference in the coefficients of thermal expansion between metal and resin, thermal expansion and contraction during operation can create tiny gaps at the joint. Selecting a suitable sealant and implementing a standardized coating process can compensate for the structural redundancy after casting, forming a tough protective barrier.
Surface Cleaning Treatment Before Coating
When treating the exposed areas of epoxy resin bushings, the primary task is to remove residual release agent or processing oil. It is recommended to use industrial-grade isopropyl alcohol for wiping until the surface has a uniform matte finish. If the surface roughness of the exposed metal parts is insufficient, appropriate sandblasting or physical grinding can be performed to increase the physical anchoring force of the adhesive, which is crucial for improving subsequent adhesion performance.
Detailed Control of Sealant Application on Exposed Parts
Applying sealant is not a simple matter of covering; it requires targeted operation based on the structural characteristics of the epoxy resin sleeve.
Adhesive Ratio and Air Bubble Removal
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Accurate Weighing: Strictly adhere to the sealant component ratio according to temperature variations in the production environment to prevent localized over-brittleness or incomplete drying after curing.
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Vacuum Degassing: It is recommended to treat the mixed adhesive in a vacuum chamber to remove tiny air bubbles introduced during stirring.
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Layered application: The application process should be pushed outwards from the inside, applying force evenly along the circumference of epoxy bushing for transformer to squeeze out any residual air at the seams.
Step-by-Step Temperature Control of the Curing Environment
For epoxy resin sleeves requiring high insulation performance, natural curing often fails to achieve the optimal cross-linking degree. We recommend a stepped curing method:
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Room temperature pre-curing stage: This allows the sealant to initially set, preventing flow and dripping.
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Medium-temperature strengthening stage: Baking at a constant temperature of 50-60°C promotes chemical bonding between the sealant layer and the casing substrate.
Daily recommendations for improving construction quality:
On daily production lines, maintaining humidity below 60% in the work area is crucial. High humidity can cause the sealant on the epoxy casing surface to whiten, reducing the light transmittance and density of the sealant layer. Furthermore, timely cleaning of coating tools is equally important; dried sealant residue falling into the treated area can create stress concentration points.
This meticulous treatment of exposed areas is a low-cost and efficient way to extend the overall service life of epoxy casings.
