Epoxy Fiberglass Board and phenolic board are two commonly used engineering insulation materials. Although they may appear similar in some industrial applications, their performance characteristics and usage scenarios are quite different. Below is a clear and professional comparison.

Phenolic cotton cloth laminated sheets are rigid, high-performance insulating materials manufactured by impregnating industrial cotton cloth with phenolic resin varnish, followed by baking and hot pressing. These materials are widely used in mechanical and electrical applications, offering tailored grades to meet diverse performance requirements, aligned with Chinese national standards, IEC standards, and NEMA-based specifications.

Phenolic laminated cotton sheet is a widely used industrial insulation and engineering material. It is manufactured by impregnating cotton fabric with phenolic resin under high temperature and pressure, resulting in excellent mechanical strength, electrical insulation performance, and machinability. According to fabric structure and performance differences, Phenolic Cotton Laminate is mainly divided into four grades: C850.1, C850.2, C850.3, and C850.4.

Phenolic Cotton Rod is a composite material manufactured through a special process by combining phenolic resin with cotton fabric. It integrates the excellent heat resistance and chemical stability of phenolic resin with the flexibility and mechanical reinforcement of cotton fibers, resulting in outstanding overall performance. As a result, it has become an essential engineering material widely used across multiple industrial sectors.

Phenolic laminates remain essential materials in electrical insulation and mechanical engineering due to their durability, stability, and insulating performance. Among them, Phenolic Cotton Board (NEMA Grade L) has gained significant attention for its balanced properties and versatility. At YILONG, we provide a wide range of phenolic materials, and understanding the differences between Grade L, Grade C, and Grade LE is key to selecting the right solution for demanding industrial applications.

With the rapid development of new energy grid integration, AI data center expansion, and smart grids, traditional power-frequency transformers can no longer meet the demands of modern power systems. Solid State Transformers (SSTs), featuring compact size, high efficiency, power quality regulation, and bidirectional energy flow, are emerging as key equipment for next-generation power grids. However, as operating frequency surges from 50 Hz to 10–30 kHz and above, while voltage levels remain medium-to-high voltage (10 kV and above) and volumes shrink drastically, insulation systems face unprecedented challenges from coupled electrothermalmechanical multi-physics fields. Reliable insulation design has become a critical bottleneck restricting the development of high-power-density SSTs.

Epoxy Board exhibits excellent performance, featuring high temperature resistance, corrosion resistance, high mechanical strength, good machinability, low water absorption, and outstanding insulation and electrical properties. There are various grades of Epoxy Board, including 3240, G11, FR‑4, G10, and others.

As a professional engaged in electrical accessory processing for many years, we have handled a large number of custom Epoxy Laminates orders. In practice, many users simply treat this material as an “insulation board,” without fully realizing that it combines excellent electrical insulation, high mechanical strength, and strong corrosion resistance, making it widely used across multiple industries.

Epoxy Sheets are widely used in construction and decorative applications due to their high strength, corrosion resistance, and ease of cleaning. However, some common issues may arise during use. Below are the typical problems and their corresponding solutions.

CTI, known as the Comparative Tracking Index, is a key parameter used to evaluate the resistance of insulating materials to electrical tracking failure (surface breakdown). It is widely applied in the quality assessment of insulating substrates used in household appliances, low-voltage electrical equipment, and high-voltage applications.