what is the influence of the loading capacity of the grinding body of the ball mill on the productionDate: 2019-07-04 Views:
Ball mill is widely used in aerated concrete industry. Steel brother thinks that the reasonable determination of loading capacity has a great influence on the ball mill, and the product quality and product efficiency can be improved.
Reasonable load of the grinding body:
1. The percentage of the ratio of the volume of the grinding body in the mill to the effective volume of the mill, referred to as the filling rate of the grinding body.
φ = VsVm × 100%
In the formula: φ-internal grinding body filling rate,%;
Vs _ volume filled by the grinding body, m3;
The effective volume of Vm-- mill (warehouse), m3.
The center of the filling surface of the grinding body is high, and the filling rate is calculated by measuring the height of the inner sphere.
In the case of no material in the mill or only a small amount of material, the effective inner diameter of the mill Di; is measured with a ruler, and then the vertical distance H from the grinding surface to the top liner is measured through the center of the mill, and then the H / D value is calculated, which is as follows:
φ = β 360-sin β 2 h = Di2cos β 2nH 1 = Di2-h=Di21-cos β 2n, in the formula:
Filling rate of φ mill grinder;
The center angle of the filling surface of the β-grinding body to the center of the mill, the distance between the center of the nh-- mill and the filling surface of the grinding body, m, and the distance between the center of the grinding machine and the filling surface of the grinding body.
Effective inner diameter of nDi-- mill, m;
The height of filling surface of nH1-- inner grinding body is m.
n Calculated H/Di.
an n-abrasive body filling rate of greater than 32%,
Second, the following empirical formula can also be used to calculate the filling rate directly.
In φ 0=113-126Hn formula:
The filling rate of φ 0 inner grinding body is%.
N when measuring the filling surface height of the grinding body, attention should be paid to the filling of the grinding material.
If the material surface is 15 ≤ 20 mm higher than the grinding body, the calculated filling rate should be subtracted by 2% ≤ 4% error.
The filling rate of the grinding body has a great influence on the grinding efficiency of the mill. Too high or too low filling rate of the grinding body will lead to the decrease of the grinding efficiency of the mill.
There are many factors that affect the optimum filling rate of the grinding body, such as the form, specification, internal structure characteristics and the performance of the ground material.
Therefore, the optimum filling rate should be obtained by the test in the production, and the appropriate adjustment shall be made according to the degree of change of the influencing factors.
The filling rate of grinding body in all kinds of grinders in cement plant of our country (aerated concrete).
The filling rate of aerated concrete (cement plant) grinder is as follows: medium unloading or tail unloading, drying mill filling rate φ (%) 25 ≤ 28, first stage closed circuit long grinding filling rate φ (%) 30 ≤ 36, open circuit long grinding filling rate (%) 25 ≤ 30, powder selection drying short ball mill filling rate (%) 35 ≤ 38, baseball mill rod bin filling rate (%) 20 ≤ 25, secondary closed circuit short ball grinding filling rate (%) 40 ≤ 45.
For the filling rate of the grinding body of the two-stage closed-circuit ball mill and the multi-warehouse mill, the filling rate should also be adjusted according to the equilibrium state of the grinding action of each stage or warehouse.
If: if a three warehouse mill in production shows that the coarse grinding ability is insufficient, and the fine grinding ability is strong, the filling rate of the first silo steel ball should be properly increased and the filling rate of the third silo steel forging (ball) should be reduced, so that the grinding effect of each warehouse can reach a relative balance.
When changing the product variety or quality requirements in production, appropriate adjustment of filling rate should also be considered.
Third, the mass of the grinding body loaded into the mill (or warehouse) is called the loading capacity of the grinding body, which depends on the filling rate of the mill.
In G ≤ V φ p nG=0.00785D2iL φ p n formula:
The loading capacity of G / M inner grinding body, t;
V / grinder (warehouse) effective volume, m3;
Di-- mill (warehouse) effective diameter, m;
The effective length of L / L mill (warehouse), m;
φ-filling rate of grinding body in the mill, %;
ρ-volume density of grinding body, t ≤ m ~ 3.
The volume density of steel ball is 4.56 × 4.85t / m ~ 3.