The spiral classifier is mostly used for the first stage of grinding. The high-grade spiral classifier is suitable for coarse-grain classification. Generally speaking, the separation particle size is greater than 0.15 mm. The sun-type spiral classifier is suitable for fine-grain classification, generally less than 0.15 mm. The length of the spiral classifier is determined according to the height of the return sanding; under the determined processing capacity, a single spiral classifier should be used as much as possible. Because the spiral working load of the double spiral classifier away from the grinding machine is 0.6 to 0.75 of the other spiral, the efficiency is low. When selecting a spiral classifier, the appropriate screw speed must be determined according to the processing capacity. Hydrocyclones are often used for the second stage of grinding or regrind operations. When selecting its specifications, it should be determined according to the required processing capacity and overflow granularity. When a large processing capacity and a thick overflow are required, a large-scale hydrocyclone should be selected, and a small-sized hydrocyclone is selected instead. Large beneficiation plant capacity but requires a very fine overflow may make use of the small size of the cyclone group. The hydrocyclone should pay attention to selecting the appropriate feeding mode when working. The pressure is usually 4.903×106～15.68×10-6Pa (0.5～1.6kgf/cm2). The large pressure converter adopts small pressure value; the specification cyclone Use a larger pressure value. The sand discharge port of the hydrocyclone is easy to wear, and the wear stability has a great influence on the stability of the cyclone. Therefore, wear-resistant materials such as cast stone or rubber should be used to make the sand discharge port. Can be adjusted. In order to eliminate the impact of the cyclone wear on the grading operation, the design of the cyclone must be considered to have a certain amount of spare. Generally, the cyclone used for classification in the grinding circuit should be considered to be used in units of 1 or 2; it is used as a cyclone for fractionation or desilting of 0.074 mm or less, and a reserve of 20 to 50% can be considered. Mining Tools,Mining Drill Bits,Carbide Mining Drill Bits,bit Zigong Brace Cemented Carbide Co.,Ltd , https://www.bracecarbide.com
Grading equipment selection principle
The main basis for classifier selection is: overflow particle size (separation particle size) and concentration; ratio of sand return to overflow flow; content of clay and other finely dispersed materials in raw ore; The selection is mainly required to separate the required overflow and its concentration and the amount of sand returned under the specified overflow particle size.