How does 3240 epoxy board achieve excellent interlaminar insulation in high-voltage electrical equipment?
Publish Time: 2025-10-09
In modern high-voltage electrical equipment, the performance of insulation materials is directly related to the system's safety, stability, and service life. As an important type of laminated insulation material, 3240 epoxy board, due to its excellent electrical properties, mechanical strength, and heat resistance, is widely used in key applications such as transformers, high-voltage switchgear, circuit breakers, motor slot wedges, busbar clamping systems, and various insulation supports. Its exceptional performance in interlaminar insulation is particularly highly valued in the power and electrical engineering fields.1. Material Structure: Laying the Foundation for Insulation3240 epoxy board is a laminated product made of alkali-free glass fiber cloth as a reinforcement and epoxy resin as a binder, produced through a hot-pressing process. Alkali-free glass fiber cloth inherently offers extremely high insulation resistance and heat resistance, as well as low moisture absorption and excellent dimensional stability. Epoxy resin, a high-performance thermosetting resin, forms a three-dimensional cross-linked network upon curing, resulting in excellent dielectric properties, chemical stability, and adhesion. The combination of the two, the glass fiber cloth, not only enhances the overall mechanical strength of the board but also effectively prevents the propagation of microcracks that may exist within the resin, significantly improving the material's arc resistance and corona resistance. This "reinforcement + matrix" composite structure enables 3240 epoxy board to form a dense, uniform insulation barrier between layers, effectively blocking lateral current leakage paths.2. High Insulation Resistance and Withstand Voltage: Resistant to Electrical BreakdownIn high-voltage electrical equipment, conductors at different potentials must be separated by reliable insulating materials to prevent short circuits or electrical breakdown. This means it is virtually non-conductive, effectively preventing the generation of weak leakage currents. More importantly, its power frequency electrical strength is typically greater than 35 kV/mm, maintaining insulation integrity under high voltage gradients. For example, in the interlayer insulation of dry-type transformer windings, 3240 epoxy board can withstand interlayer voltages of several thousand or even tens of thousands of volts, ensuring that potential differences between turns do not cause discharges or breakdown, thereby ensuring long-term stable operation of the equipment.3. Heat Resistance and Thermal Stability: Ensuring Insulation Reliability at High TemperaturesHigh-voltage equipment generates significant heat during operation, especially during peak loads or fault conditions, where local temperatures can rise significantly. 3240 epoxy board has a heat resistance rating of F, with some high-quality products even achieving H. This means it maintains excellent mechanical and electrical properties even under long-term operating temperatures, preventing degradation of insulation performance due to thermal aging. Furthermore, the tight interface between the epoxy resin and the glass fiber, resulting in a well-matched thermal expansion coefficient, reduces internal stress and delamination caused by temperature cycling, further enhancing the durability of interlaminar insulation.4. Arc and Creepage Resistance: Coping with Extreme Operating ConditionsTransient arcs can occur within electrical equipment during switching operations or short-circuit faults. 3240 epoxy board offers excellent arc resistance, rapidly carbonizing under the action of arcs to form a non-conductive residue, preventing arc propagation along the surface. Furthermore, its smooth surface and low water absorption significantly reduce the risk of surface leakage and flashover. In practical applications, engineers often use 3240 epoxy board to create interlayer spacers, insulating partitions, or support bars. This increases creepage distances and isolates live conductors, creating safe insulation pathways and effectively preventing interlayer flashover accidents.5. Processing Precision and Structural Adaptability: Improving Overall Insulation Effectiveness3240 epoxy board is easy to machine and can be precisely cut, drilled, and milled to meet the assembly requirements of complex structures. In high-voltage equipment, interlayer insulation often requires precise alignment with copper busbars, cores, or windings. Through precision machining, 3240 epoxy board allows for seamless insertion, preventing partial discharge caused by gaps or burrs. Furthermore, its high strength and flexural resistance ensure that it resists cracking or deformation during fastening and assembly, maintaining the integrity of the insulation structure.In summary, 3240 epoxy board, with its superior material composition, high dielectric strength, thermal stability, arc resistance, and excellent processing properties, plays an irreplaceable role in interlayer insulation in high-voltage electrical equipment. It not only provides reliable electrical isolation function, but also has structural support and environmental protection capabilities. It is one of the key materials to ensure the safe operation of the power system.
