The role of carcass is to withstand the forces from the inside and outside of the rubber conveyor belt, improve the strength of the rubber belt, and limit its deformation. It largely determines the performance, service life and use value of rubber conveyor belt. The carcass is made of textile fiber (including natural fiber and chemical fiber), steel cord, glass fiber, etc.
Cotton Canvas
Cotton canvas mainly includes polyester/cotton, acrylic cotton, pure cotton. Cotton fiber has the characteristics of good adhesion to rubber. The conveyor belt made of cotton canvas has the advantages of good flexibility, good troughability, and low price. It is mainly suitable for medium and short distance transportation of small lump and powder materials (wood chips, rice, cement and ore, etc.). The disadvantages of cotton canvas are low breaking strength, easy corrosion, and short fatigue life.
Nylon Canvas
Nylon canvas warp and weft are both nylon fibers. Its advantages are good wear resistance, fatigue resistance and high strength. Conveyor belts made of nylon canvas have below advantages:
- thin body
- high strength
- impact resistance
- good trough-ability
- good bonding strength
- excellent flexing performance
- long service life
But the low modulus of nylon fiber, high elongation at break and high elongation at certain load will cause the conveyor belt longer and longer. Therefore, at present nylon canvas is mostly used in conveyor belts with moderate transportation distance, large safety factor and good elasticity.
Nylon canvas mainly includes nylon 6 and nylon 66 canvas. Nylon 66 has the same physical properties as nylon 6, but has a higher melting point and better heat resistance. Therefore, nylon 66 canvas is used in high-performance, high-quality conveyor belts and heat-resistant conveyor belts. Nylon 6 is cheap and helps reduce the production cost of conveyor belts.
Polyester Canvas
Polyester fiber has the characteristics of high modulus and low shrinkage. Polyester canvas includes polyester canvas and polyester/nylon canvas. In addition to the advantages of nylon canvas, polyester canvas also has the advantages of
- low elongation
- good heat resistance
- low price
Polyester/nylon canvas is made of ordinary or high modulus and low shrinkage polyester as the warp yarn and nylon 66 as the weft yarn. Therefore, the canvas has the advantages of small warp elongation and good weft trough-ability, so it is the main canvas used in the conveyor belt.
Conveyor belts made of polyester canvas have the advantages of high belt modulus, low elongation, fatigue resistance, impact resistance and good trough-ability. Therefore, polyester canvas is mainly used for long conveying distances, large loads, and chemical resistance.
Aramid
Aramid has obvious advantages as a conveyor belt carcass, especially when it is used on ultra-high-strength fabric conveyor belts with a breaking strength greater than 1800N and even as high as 4000N. The elongation of the aramid conveyor belt can be lower than 0.5%. In the case of equal quality, the strength of aramid is about 7 times that of steel cord, and its modulus is twice that of steel cord, so it has the reputation of “synthetic steel cord”.
The use of aramid as the carcass of the conveyor belt can extend the distance of a single machine, reduce the thickness of the belt body and the weight of the conveyor belt itself, which can not only reduce the power consumption of the conveyor itself, but also enhance the stability of the conveyor belt operation. Reduce the workload of maintenance and facilitate the handling, installation and disassembly of the conveyor belt.