The vertical cylindrical fine screen, also known as the conical hydraulic grading screen, is called Huji Screen in foreign countries. It was first proposed by Professor Hukki R.T. of Finland in 1979, and has achieved remarkable results for secondary grading. Maanshan Institute of Mining research laboratory in 1981 Ñ„400mm vertical cylindrical fine sieve, and later developed Ñ„1m and Ñ„2m of industrial-type vertical cylindrical fine sieve, and the Nanshan Iron ore and iron ore in Tangshan City, Malan village Industrial trials were conducted together. According to the calculation of 0.076mm, the quantitative efficiency is 85.61% and 60.95%, and the mass efficiency is 64.80% and 46.79%. It can be used in the production process to improve the processing capacity of ore concentrate or improve the grade of iron concentrate. One of the better fine-grain screening and grading equipment . The machine is mainly composed of motor, reducer, tank, water jacket, impeller, sieve plate, feeding cylinder and hose valve (Fig. 1). The cylindrical sieve includes screen frame and screen surface. The screen frame is welded by flat steel and round steel, and the screen surface is composed of 53 nylon-shaped sieve plates to form 6 large sieve plates. According to the requirements of the graded products, the sieves can be replaced with sieves of 0.15, 0.20 and 0.30 mm. board. In order to find suitable operating conditions, the conditions of impeller rotation, ore supply, ore size, rising water flow, and screening slurry concentration were tested. The results are shown in Fig. 3 to Fig. 7. Playground Combination Rope,Fiber Core And Steel,Wire Rope,Pp Danline Rope Yangzhou Jieerte Steel Cable Co., Ltd , https://www.nbjieertesteelcable.com
A structure and principle 
The following is the technical performance of the Ñ„2m vertical cylinder fine screen:
Sieve diameter 2000mm
Effective screening area 2.0m 2
Screen angle 90°
Screen size 0.15, 0.20, 0.30mm,
Impeller diameter 1850mm
Impeller rotation number 22~41r/min
Motor power 7.5kW
Production capacity 30~50t/h
Pulp concentration <40%
Dimensions 3000×3000×3500mm
Machine weight 3000kg
The working principle is that when the slurry is fed into the ore cylinder in a tangential direction, the slurry falls evenly on the rotating impeller along the circumference of the cylinder. Due to the combined action of centrifugal force, gravity, rising hydraulic force and mechanical stirring force, the slurry is made to a certain extent. The angular velocity rotates around the inside of the fine screen of the cylinder, and the fine particles in the slurry pass through the sieve hole to be discharged into the sieve product; the coarse particles and the fine particles mixed therein are dropped from the inner side of the cylindrical sieve into the cone, during the falling process of the material. In the middle, it is subjected to the rising water in the introduction cone, and the fine particle portion thereof is raised through the draft tube into the impeller interlayer to enter the inside of the cylindrical sieve, and is again sieved with the newly fed slurry. After the coarse fraction passes through the rising water flow, it continues to fall to the sand discharge port and becomes the product discharged on the sieve.
According to the nature of the ore and the requirements of the graded products, the most suitable impeller rotation number and rising water consumption of the machine are determined by experiments. [next]
B Industrial test
The industrial test of the machine was first carried out at the Nanshan Iron Mine Concavation Plant. The equipment was installed in the third production series, and the overflow of the spiral classifier was treated. The overflow of -0.125mm accounted for 40~50%, and -0.076mm accounted for 30 to 35%. The process is shown in Figure 2.