Bakelite board, also known as phenolic laminated sheet, is one of the most widely used electrical insulation materials in low-voltage and medium-voltage equipment. Among all applications, its use in switch cabinets and switchgear systems is particularly important due to its stable dielectric performance, high mechanical strength, and excellent thermal resistance. As electrical systems evolve toward higher safety and efficiency, the demand for reliable switch cabinet insulation materials continues to grow. According to industry estimates, global consumption of thermosetting insulation materials maintains an annual growth rate of 4–5%, driven by the expansion of power distribution and industrial automation sectors.
1. High Dielectric Strength Ensures Electrical Safety
Bakelite board provides excellent electrical insulation performance, with dielectric strength typically reaching ≥10kV/mm, depending on thickness and grade. This makes it suitable for insulating busbars, isolating electrical compartments, and preventing arc flash risks in LV and MV switchgear.
2. Excellent Mechanical Strength for Structural Support
Switch cabinets require materials that can withstand compression, bending, and long-term mechanical stress. Phenolic boards have a tensile strength of ≥100 MPa and flexural strength of ≥120 MPa, ensuring dimensional stability even under continuous mechanical load.
Typical applications include:
► Equipment mounting panels
► Support brackets and partitions
► Insulating spacers and busbar supports
These functions directly enhance mechanical reliability in electrical control panels and distribution cabinets.
3. Strong Heat Resistance for Long-Term Operation
In switchgear environments, the internal temperature often ranges between 70°C and 120°C depending on load conditions. Bakelite board’s heat-resistant Class B rating (up to 130°C) prevents deformation, cracking, and degradation during long-term operation. Compared with thermoplastic materials, phenolic sheets maintain stability even under sudden temperature fluctuations.
1. Busbar Insulation and Support
Bakelite’s high dielectric strength and arc resistance make it ideal for busbar insulation barriers in low-voltage switchgear (such as MNS, GCK, GCS cabinets).
2. Partition Boards and Isolation Barriers
To ensure operator and equipment safety, switch cabinets require insulating barriers that resist electrical leakage and arc propagation. Bakelite boards satisfy both safety and mechanical rigidity standards.
3. Equipment Mounting Plates
Phenolic laminated sheets are frequently used as device mounting plates for relays, contactors, terminal blocks, soft starters, and meters because they are easy to machine and resistant to vibration.
4. Supporting Components and Machined Parts
With CNC machining, Bakelite can be processed into:
► Arc barriers
► Insulation pads
► Gaskets
► Washers
► Customized insulating blocks
These components enhance overall switchgear insulation reliability.
| Material | Heat Resistance | Mechanical Strength | Cost | Switchgear Suitability |
|---|---|---|---|---|
| Bakelite (phenolic) | ★★★★ | ★★★★ | Low | Excellent |
| FR4 Fiberglass Sheet | ★★★★★ | ★★★★★ | Medium | Excellent but higher cost |
| PVC/ABS | ★★ | ★ | Low | Limited use |
| Electrical Paperboard | ★★ | ★★ | Low | For low-load panels only |
Thus, Bakelite board becomes the best cost-effective solution for large-scale manufacturing of switch cabinets and power distribution units (PDU).
The application of Bakelite boards in switch cabinets is essential for maintaining electrical safety, mechanical stability, thermal resistance, and cost efficiency. With growing global demand for reliable switchgear in industrial plants, commercial buildings, and utility networks, the use of phenolic laminated sheets will continue to expand.
For manufacturers and engineers seeking durable and economical switch cabinet insulation materials, Bakelite board remains one of the most reliable solutions in the market.
