The ball mill is composed of horizontal cylinder, inlet and outlet hollow shaft and grinding head, the cylinder is long cylinder, the cylinder is equipped with grinding body, the cylinder is made of steel plate, the liner and the cylinder are fixed, the grinding body is generally steel Made of balls, and according to different diameter and a certain proportion into the tube, grinding body can also be used steel section. Ball mill is widely used in industrial sectors such as mining, cement, chemical industry and electric power. The main working mechanism is the cylinder with grinding medium, which crushes the material by the impact of the medium during the rotation of the cylinder.
This series of ball mill wet plaid ball mill for mineral processing, chemical, cement, construction and other industrial sectors wet grinding at all levels of hardness of the ore and materials used.
Ball mill is mainly composed of cylindrical cylinder, end cap, bearing and transmission large ring gear and other components, the cylinder into the diameter of 25-150mm steel ball or steel bar, known as the grinding medium, the loading capacity for the entire cylinder There is a relatively large volume of 25% -50%. The ends of the cylinder are end caps, and the end caps are connected with the end flanges of the cylinder by means of screws. The middle part of the end caps has holes, which are called hollow journals and hollow journals are supported on the bearings. A large gear 4 is also fixed on the cylinder. In the drive system, the motor through the coupling, reducer and pinion drive large gear wheels and cylinder, slowly turn. When the cylinder rotation, grinding with the cylinder rose to a certain height, and then was a parabola falling or diarrhea down. As the end cap has a hollow journal, the material from the left side of the hollow journal into the cylinder, and gradually spread to the right to move, when the material from left to right during the move, the rotating cylinder to the ball to a certain Height and fall will be crushed material, and part of the ball in the cylinder into the diarrhea state of the material grinding effect, the entire process is the process of grinding the material.
The working principle of the ball mill, due to the rotation of the cylinder and the grinding of the movement, the material gradually spread to the right, and finally from the right hollow journal overflow discharge, the type of ball mill known as overflow ball mill.
Another kind of ball mill in the right end (discharge end) with a grid plate, the grid board consists of a number of fan-shaped perforated plate composition, fan-shaped plate on the hole width of 7-20mm, generally 7-8mm is appropriate, the material can Through the grate hole into the space between the grid plate and the end cap, and then by the board, the material up to lift, the material stretched through the cone slide through the cone-shaped block to the right to the hollow journal, and then by the hollow journal discharge machine outside.
The third way is to use the wind nesting, wind discharge ball mill. Material from the feed port into the ball mill, with the mill rotation, grinding mill grinding (steel) on the material impact and grinding, the material from the left side of the mill (import) ashamed to move to the right, in the process of moving Material broken, grinding process. In the ball mill outlet end connected with the duct, in the pipeline system in series with the separator, cyclone, dust and fan imports. When the wind power system to drive, the ball mill body is also in low negative pressure operation. When the grinding of the material with the mill into a loose rotation, and with the wind from the outlet into the pipeline system, the coarse particles separated by the separator and then into the ball mill imports, fine powder separated by the separation of gas, gas By the fan into the atmosphere.
When the ball filling rate (the total volume of the ball in the cylinder volume of the volume of the percentage) accounted for 40% -50%, the ball mill at different speeds of rotation, the cylinder of the grinding medium may occur three basic state of motion. In the first case, the speed is too high, the centrifugal force causes the ball to rotate together with the cylinder. The whole ball forms a ring which is in close contact with the inner wall of the cylinder. It is called "working state", which can not reach the impact of the material Grinding effect. In the second case, the speed is too slow and the material and the mill are rotated up to 40 ° -50 ° along the mill (there is also a relative slippage between the layers during the rise), when the grinding and material Body friction is equal to the dynamic friction angle, the friction and material on the decline, known as the "diarrhea state." The material has a grinding effect, but no impact on the material, so that the grinding efficiency is poor. The third case, the mill speed is relatively moderate. Grinding along with the cylinder to a certain height, leaving the circular orbit along the parabolic trajectory is free falling, called "throwing state", along the parabolic trajectory of the ball, the lower part of the cylinder ball or tube Body liner produces impact and grinding, so that the material crushed.
1, the installation of the basic requirements
2, the general requirements of the installation