Why are phenolic paper tubes most commonly used in the electrical and electronics industry?
In this field, fundamental components directly impact the safe, reliable, and efficient operation of the entire system. Phenolic paper tubes, also known as phenolic sleeves or insulating paper tubes, are common components in this field and can be found in transformers, motors, relays, and various electronic devices. This article will analyze the six core reasons for the widespread use of phenolic paper tubes in the electrical and electronics industry and explain their application value.
1. Excellent Electrical Insulation
This is the core value of phenolic paper tubes, meeting the primary need in the electrical industry to prevent current leakage and short circuits.
High Dielectric Strength: They can withstand high voltages without breakdown, providing an insulating barrier between coils, conductors, and cores.
Stable Insulation Resistance: They maintain a stable high resistance under varying environmental conditions, ensuring long-term insulation.
Based on these properties, phenolic paper tubes are suitable for protecting precision electronic components and high-voltage power equipment.
2. Excellent Mechanical Strength and Rigidity
Electronic components require insulation protection as well as structural support. Phenolic paper tubes meet these requirements:
High Strength and Hardness: They provide a support framework for transformer and inductor coils, preventing deformation and damage during winding, transportation, and operation.
Excellent Dimensional Stability: They maintain their shape and dimensions in environments with fluctuating temperature and humidity, ensuring the stability of the device's internal structure.
3. Reliable Heat Resistance
Electrical and electronic equipment generates heat during operation. Phenolic paper tubes are made from insulating paper impregnated with phenolic resin and then heat-cured. They offer excellent heat resistance:
They typically reach Class B (130°C) or even higher operating temperatures, allowing them to withstand the high temperatures generated by normal equipment operation and short-term overloads without melting, dripping, or losing their insulating properties.
4. Excellent Processability and Adaptability
The processing characteristics of phenolic paper tubes expand their application range:
They can be cut into various lengths and shapes according to design requirements.
In transformer manufacturing, the entire coil, including the phenolic paper tube skeleton, can be vacuum-impregnated to improve overall insulation strength, moisture resistance, and heat dissipation.
5. High Cost-Efficiency
In large-scale industrial production, cost is a key consideration, and phenolic paper tubes offer cost advantages:
Low Raw Material Cost: The main components are paper and phenolic resin, which are widely available and relatively low in cost.
High Production Efficiency: The mature manufacturing process enables large-scale, efficient production. Compared with insulating materials such as ceramics, some engineering plastics or silicone rubber, phenolic paper tubes have lower costs while meeting most application requirements.
6. Excellent Chemical and Moisture Resistance
After being impregnated and cured with phenolic resin, phenolic paper tubes are resistant to a wide range of chemical solvents, oils, grease, and moisture. The protective film formed by the resin prevents the degradation of insulation performance due to moisture absorption, ensuring long-term reliable operation of equipment in harsh environments.
Phenolic paper tubes offer a balanced combination of electrical insulation, mechanical strength, heat resistance, processability, chemical resistance, and cost. Thanks to these comprehensive properties, phenolic paper tubes have become a popular insulating structural material in the electrical and electronic fields over the past few decades. Despite the emergence of new engineering plastics such as PBT, PET, and PPS, phenolic paper tubes remain widely used in many traditional and modern applications due to their reliability and cost advantages.
