In the manufacturing of electrical equipment such as motors, transformers, and generators, the quality of winding insulation directly determines the product's lifespan, safety, and energy efficiency. Traditional immersion or trickle impregnation processes often suffer from issues like uneven impregnation, trapped air bubbles, and incomplete curing, making them inadequate for modern high-power-density, high-reliability equipment. Vacuum Pressure Impregnation (VPI) technology has become the standard process in global high-end electrical manufacturing—and its key lies in a high-performance VPI system.
How Does VPI Achieve "Zero-Defect" Insulation?
The VPI process addresses the pain points of traditional methods through three steps of precise control:
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High-Vacuum Degassing: The workpiece is placed in a vacuum chamber to evacuate air and moisture from within the windings and their interstices, ensuring the resin can penetrate the finest structures.
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Pressure Impregnation: Following vacuum, insulating resin is introduced and a pressure of 0.3–0.8 MPa is applied to force the resin into every void.
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Uniform Curing: In conjunction with a curing oven system, complete resin cross-linking is achieved, forming a dense, bubble-free monolithic insulation layer.
Clients Gain More Than Just "Thorough Impregnation"—They Achieve Comprehensive Value Enhancement:
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Leap in Insulation Performance: Breakdown voltage increases by over 30%, with thermal endurance reaching Class H or even Class C.
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Enhanced Mechanical Strength: The windings are cured into a solid unit, significantly improving resistance to vibration and shock.
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Optimized Heat Dissipation: Eliminating air gaps enables more uniform thermal conductivity, reducing temperature rise and extending equipment life.
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Win-Win for Eco-Friendliness and Cost: The closed system reduces resin waste, lowers VOC emissions by 50%+, and aligns with green manufacturing trends.
Our independently developed VPI equipment features a modular design, intelligent PLC control, and a dual-vacuum system for redundancy. It supports various resin systems including epoxy, polyester, and unsaturated resins, and has successfully served high-end sectors such as wind power, high-speed rail, and new energy vehicle electric drives.