First, the basic concept of rubber
There are many kinds of rubbers, each with its own characteristics, and it is very important to manufacture rubber rollers. How to achieve the "suitable materials" is very important. The basic knowledge of rubber is as follows:
1. Natural rubber (NR)
Excellent processability and physical properties, but lack of oil resistance, heat resistance, ozone resistance. Commonly used in tires, footwear, rubber hoses, rubber belts & mdash; — and so on. The rubber roller is suitable for applications where heat resistance and oil resistance are not required and the price is low.
2. Synthetic rubber (SBR)
The nature is similar to that of NR, and its use is the same. Domestic synthetic rubber has been produced since 1967.
3. Synthetic rubber (NBR)
It is an oil-resistant synthetic rubber, commonly known as Hycar, which is widely used in printing rolls. Excellent heat resistance and wear resistance. Whether the oil resistance is good or not depends on the amount of Acrylonitrile. The disadvantage is that ultra-low hardness is difficult to manufacture.
4. Synthetic rubber (CR)
Synthetic rubber (trade name Neoprene) developed by DuPont of the United States is excellent in mechanical strength, abrasion resistance and elasticity, and has moderate oil resistance, chemical properties, heat resistance and ozone resistance, and is widely used in general industrial applications. Rubber rod wheel.
5. Synthetic rubber (EPT)
Poor oil resistance, but very good polar solvents such as ketones and esters. Because it is excellent in heat resistance and chemical resistance, it is widely used for coating, surface and printing rollers, or industrial rollers for general heat resistance and chemical resistance.
6, synthetic oak (CSM)
The same as CR, it is a synthetic rubber (trade name Hypalon) developed by DuPont, heat resistance, chemical resistance, and ozone resistance. Excellent weather resistance and wear resistance. Expensive is its disadvantage.
7. Synthetic rubber (Si)
The scientific name of Silicone Rubber, heat resistance up to 220 & deg; C, the cold resistance is also high, because of the non-stick characteristics, so PE extrusion roll, PVC tape embossing wheel and tape guide roller are widely used. Other Heat Seal rolls and Sizing Rolls can also be used. The weakness of mechanical strength and the high cost are disadvantages.
8. Synthetic rubber (PU)
Poly Urethane Rubber has excellent mechanical properties, abrasion resistance and solvent resistance. Heat resistance and stagnation resistance are not good. It is generally manufactured by liquid injection molding and is widely used in industries such as iron making, paper making, and printing glazing.
9. Liquid silicone wheels (RTV Rolls)
Liquid non-stick rubber wheels made of liquid enamel rubber (RTV Rolls) are widely used in PVC, PE, PP and other plastic industries, and have good release properties.
Rubber hardness and thickness
Most of the rubber rollers use their good elasticity, so the choice of hardness and thickness is carefully decided. The choice of rubber hardness or thickness can not be arbitrarily chosen, but has a certain limit.
Because it is difficult to make high-strength rubber below JISA40 hardness, high-weight rubber rollers cannot be formulated with low hardness. The soft rubber has a very large compression deformation, and the internal heat is prone to aging and shortens the service life.
When the hardness is measured by a spring-type hardness tester, in principle, the rubber thickness is 12mm or more, and when the rubber roller rubber thickness is less than 12mm, the hardness will be higher due to the influence of the iron core during the measurement, especially the soft rubber. Greater impact. In addition, the measurement surface is smooth, and the pin is perpendicular to the measurement surface, and the pressure surface and the auxiliary pressure surface are gently contacted with the measurement surface to read the degree by the scale.
Rubber hardness and thickness determination measures
Combustion test of various rubbers
Rubber (Wheel Wheel >
)Heat resistance