With the using range of gum powder continuous expanding, the market demand for rubber powder is also increasing year by year. But the screening system is strictly control the size of the material particle size and screening capacity. Generally speaking, when the particle size of gum powder is －0.074 + 0.038 mm, the viscosity of gum solution is the highest, the water insoluble matter content is the lowest, while when the particle size of gum powder is -0.038mm, the viscosity of gum solution is greatly reduced. Therefore, screening device is very important in the whole production line, and it directly determined the product quality and working efficiency.
The structure design of new vibratory separator
The influence factors of screening efficiency
The mainly influence factors of screening efficiency have two accepts, 1. character of material, including liquidity of material ( Adhesion, loose density, humidity), size and other material features. 2. The parameter of vibratory separator, mainly including vibration parameter ( frequency, amplitude, vibration direction, angle), structure of screen deck.
The structure design of new vibratory separator
The vibration parameter of vibratory separator mainly include in frequency, amplitude, angle of eccentric block, etc. The screening of gum powder belongs to classfication of fine material, vibration with high frequency and low amplitude is generally selected. According to the research, testing and production experience, it is considered that the frequency is 1500 n /min, the amplitude is 1 ~ 4 mm, and the angle of eccentric block is 45°, these will be the best choose.
Beside the vibration parameter of vibratory separator, the screen deck structure if vibratory separator is also one of the factor affecting the screen efficiency. In short, when the material movement track is same, the larger the screen surface area, the greater the probability of screening through. The most simple and effective way to improve the sieve passing rate is to increase the diameter of the screen deck by changing the structure of the screen deck. According to the screening capacity, the maximum diameter of vibratory separator is about 2,000mm. If the diameter is excessively increased, the stability of vibratory separator and strength of spare parts will be greatly affected. At present, the diameter of the vibratory separator has reached 1500 mm, and increasing the diameter cannot change the output. As a result, a new structure of vibratory separator is designed without changing the diameter. Firstly, screening the material on the meshⅠ, sieve passing material goes through the funnel parts into the lower screen frame, then the material is discharged from the lower outlet. On the meshⅠmaterials failed to timely through screen will back to the tray to mesh Ⅱ for secondary screening. Sieve passing material will entire the lower screen frame and discharged from the lower outlet port, not passing screen material will discharge from the upper outlet port. For the influencing factors of screening efficiency, the vibratory separator is a scheme to increase the screen area in a disguised way.
The capability of the new vibratory separator is tested by experiments. The experiment results show that the percentage of smaller particle size material on the screen surface of the new vibratory separator is almost 30% lower, and the screening efficiency of the new one is higher than the ordinary one.