What are the commonly used reinforcing materials in rubber transmission belts

As a key power transmission component in mechanical equipment, rubber transmission belts are widely used in automobile manufacturing, agricultural machinery, industrial equipment, food packaging and other fields. In structural design, although the elasticity and flexibility of rubber itself are good, its load-bearing capacity is limited. In order to improve the tensile strength, fatigue resistance, tear resistance and heat resistance of the transmission belt, the selection of reinforcing materials is crucial. Reinforcing materials are not only the core influencing factors of the life and performance of the transmission belt, but also the technical guarantee for the reliability and efficient operation of the transmission system.

Polyester Cord
Polyester cord is the most widely used type of reinforcing material in the current rubber transmission belt. It has good tensile strength and dimensional stability, and is particularly suitable for medium load and medium and high speed operation. Polyester fiber has good stability in a hot and humid environment and is not easy to deform. It is widely used in automotive V-belts, agricultural machinery transmission belts, and industrial V-belts.
Polyester cord also has low elongation and strong adhesion. It has strong bonding with the rubber matrix and can effectively prevent delamination and degumming problems. It is moderately priced and is one of the most cost-effective reinforcing fibers at present.

Aramid Fiber
Aramid fiber (such as Kevlar, Twaron) is a high-performance organic synthetic fiber with ultra-high tensile strength and impact resistance. Aramid reinforced materials are widely used in high-end products such as synchronous belts, variable speed belts, heavy-duty mechanical transmission belts, etc. that require extremely high strength.
The characteristics of aramid fiber include: light weight, high tensile modulus, strong thermal stability, corrosion resistance, fatigue resistance, and are particularly suitable for high-speed, high-temperature, and heavy-load occasions. At the same time, its low friction coefficient can reduce heat accumulation and extend service life.
Due to its high cost, aramid is usually used in high-end equipment or demanding working environments, such as racing engines, mining conveying equipment, and aviation transmission systems.

Glass Fiber
Glass fiber is an inorganic reinforcing material that is often used in the tension layer of rubber synchronous belts. Its main characteristics are excellent heat resistance, extremely high dimensional stability, and almost no deformation under long-term high-temperature operation conditions. It is suitable for occasions with strict requirements on synchronization accuracy in precision transmission systems.
Glass fiber is resistant to acid and alkali corrosion and is suitable for power transmission in chemical equipment. However, its flexibility is not as good as that of organic fibers, and its bending fatigue resistance is relatively weak, so it is mainly used in closed transmission belt structures.

Nylon Fabric
Nylon fabric is a common reinforcing skeleton material, mostly used as the covering layer or middle layer of wrapped V-belts, banded belts and flat belts. It has good wear resistance, flexibility and impact resistance, which helps to improve the flexural resistance of the transmission belt.
Nylon fabric also has good adhesion and machining properties, which can enhance the surface friction characteristics of the transmission belt and is suitable for use in equipment with frequent starting and stopping and large load changes.

Steel Cord
Steel cord reinforcement materials are mostly used in heavy-duty rubber conveyor belts and some high-power transmission systems, providing super tensile strength and stability. The steel cord reinforcement layer can make the transmission belt have extremely strong tear resistance and long-distance tensioning ability, which is the first choice for heavy-duty and large-span transmission systems.
The advantages of steel wire ropes are their high linear strength and long service life. They are not affected by environmental factors such as high temperature, humidity, and oil pollution, and are suitable for heavy industrial scenes such as mines, ports, and building materials.

Carbon Fiber
As a new high-performance reinforcement material, carbon fiber has extremely high specific strength and specific modulus, and extremely low thermal expansion coefficient. Although its application in rubber transmission belts is still in the development stage, its excellent high temperature resistance, fatigue resistance, and lightweight performance are gradually gaining market attention.
Carbon fiber reinforcement layers are suitable for mechanical systems that require extremely high dynamic response and high-precision synchronization, such as high-end CNC machine tools, robots, medical equipment, and other fields.

Hybrid Reinforcement
In specific applications, a single reinforcement material may not meet the comprehensive performance requirements. Composite reinforcement structures have been a development trend in recent years, such as composite solutions such as aramid + glass fiber, steel wire + nylon cord, which can take into account multiple characteristics such as strength, flexibility, heat resistance, and fatigue resistance.
The advantage of composite materials is that their performance can be customized according to application requirements, optimizing the belt structure and service life. They have been widely used in special machinery, high-precision conveying systems and multi-scenario industrial automation.