First, the principle of magnetic separator After the slurry is fed into the tank by the ore tank, the ore particles enter the tank feeding area in a loose state under the action of the water flow to the mine sprinkler pipe. In the action of the magnetic field, the magnetic ore particles are magnetically aggregated to form a "magnet" or "magnetic flux". The "magnet" or "magnetic flux" is magnetically applied to the magnetic pole, moves toward the magnetic pole, and is adsorbed on the cylinder. . Since the polarities of the magnetic poles are alternately arranged in the direction of rotation of the cylinder, and are fixed during operation, the "magnet" or "magnetic flux" is magnetically agitated due to the alternating magnetic poles when being rotated with the cylinder, and is mixed. The non-magnetic minerals such as gangue in the "magnet" or "magnetic flux" fall off during the flipping, and the "magnet" or "magnetic lotus" that is finally attracted to the surface of the cylinder is the concentrate. The concentrate passes to the weakest point of the magnetic system at the edge of the magnetic system, and is discharged into the concentrate tank under the action of the flushing water jet discharged from the unloading water pipe. If it is a full magnetic magnetic roller, the unloading is performed by a brush roller. Non-magnetic or weakly magnetic minerals are left in the slurry with the slurry exiting the trough, which is the tailings. Second, the type of magnetic separator There are many kinds of magnetic separators: they can be divided into dry strong magnetic disk type magnetic separator, flat ring type strong magnetic field magnetic separator, SHP type wet strong magnetic field separator, vertical ring wet strong magnetic field separator. (1) Dry-type strong magnetic field disk magnetic separator Dry magnetic separator is a commonly used iron ore equipment and manganese ore equipment, and the mainstream strong magnetic separator mineral processing equipment. Divided into: one cylinder three-roll dry strong magnetic separator, two cylinder two-roll dry magnetic separator, one cylinder one roller dry magnetic separator; dry strong magnetic disk disc magnetic separator is widely used for sorting less than 2 - Re-selection of 3 mm weak magnetic minerals and rare metal ores. It has three types of single disc (diameter φ = 900 mm), double disc (φ = 576 mm) and three discs (φ = 600 mm). The magnetic field strength can reach 880-1440 kA/m. Among them, there are many double disc applications with φ576 mm. The main part of the magnetic separator is composed of a "mountain" shaped electromagnet and a rotatable suspension induction disc. The disc is like a flip-flop dish with a diameter that is about one-half larger than the width of the ore belt. The disc is driven by a worm and worm gear, and the pole between the disc and the electromagnet can be adjusted by the handwheel. Distance (adjustment range 0-20) mm. In order to prevent clogging, a weak magnetic field pole is placed in the ore cylinder to pre-discharge the ferromagnetic mineral in the feedstock. (2) The flat ring type strong magnetic field magnetic separator The flat ring type strong magnetic field magnetic separator is characterized by the use of a ring chain to debate the closed magnetic circuit, the copper tube is wound around the coil, the low voltage and the large current are excited, and the water is cooled and cooled. The tooth plate is used as a sorting medium. The machine consists of a feeding device, a concentrate and a medium mine flushing device, a sorting and rotating ring, a magnetic system, a mining device, a transmission device, and a DC power supply. The magnetic structure is novel. It consists of inner and outer concentric annular magnetic moments, radial cores and coils. The main shaft is located at the center of the annular closed magnetic circuit, and no magnetic lines pass. The coil is wound from a square copper tube of 22 x 15 x 2 mm, each outer core coil 33 turns, the inner core coil 66 turns, and abuts against the pole. The heat dissipation of the coil adopts the water internal cooling method, which has the advantages of good cooling effect, low cost and no noise. (3) SHP type wet magnetic field magnetic separator SHP type wet magnetic field magnetic separator is also called double disc strong magnetic separator. It is a magnetic separation equipment which is simulated by the foreign JONES magnetic machine. Two upper U-shaped yokes are mounted on the steel frame, and an exciting coil is placed on the horizontal portion of the yoke, and forced cooling is performed by an axial flow fan. The upper and lower sorting discs are mounted on a vertical central axis, and the disc rotates between two opposing magnetic poles, and a large closed magnetic circuit is formed by the U-shaped yoke magnetic pole and the upper and lower two sorting discs, and The upper and lower sorting disks are the main circuits in the magnetic circuit. There are 17 sorting chambers on the periphery of the disc, and a multi-layer magnetic cleat is installed in the chamber to become an inductive magnetic pole. The disc is equipped with a collecting pipe, and there is a collecting tank below, and the corresponding part of the collecting pipe is provided with a feeding nozzle. (4) Vertical ring wet type strong magnetic field magnetic separator The φ800 mm vertical ring wet type strong magnetic separator mainly consists of a metal ring. The ring rotates vertically between the two magnetic poles, and the lower part passes through the magnetic field. The slurry is fed into the ring through the inner ring of the ring through the inner ring of the ring. The weak magnetic mineral particles adhere to the surface of the medium ring and rise to the magnetic field with the rotation of the ring. The very weak top is flushed into the concentrate tank by high pressure water. The non-magnetic ore particles flow into the tailings trough due to the magnetic force passing through the gap of the medium ball. The main advantage of the vertical ring wet magnetic field magnetic separator is that it overcomes the disadvantage of the horizontal ring (flat ring) magnetic separator being easy to block. This is because the medium rolls in the ring with the ring rotation, which destroys the orientation formed by the medium magnetization. Arranged to degauss, thereby improving the clogging phenomenon. The magnetic separator test shows that the specific magnetic susceptibility for hematite, siderite, ilmenite, chromite, wolframite, antimony ore, manganese ore, garnet, smectite and hornblende is greater than 15×. A sorting index of fine particle weak magnetic minerals of 10-6 cm 3 /g can obtain better sorting index. Third, the failure analysis of the magnetic separator (1) The magnetic separator motor overheats and its sound is abnormal. The reason why the magnetic separator motor overheats and its sound is abnormal is: 1) the bearing is poorly lubricated or the wear is serious; 2) the fan blade is detached or worn; 3) the switch circuit is connected. Poor touch, or single-phase disconnection; 4) The voltage is too low. (2) The magnetic separator is not sounding properly during operation, the cylinder is caught by the obstacle, and even the cylinder cannot be rotated, and the bottom box vibrates. The reason is often that the object in the bottom box is stuck, and then the magnetic block is detached, so that the cylinder creaks, and in severe cases, the barrel is scratched. At this time, stop the vehicle for repair and troubleshoot. (3) Reducer overheating The reasons are as follows: 1) insufficient oil or poor oil quality; 2) excessive wear of gears and worms, or poor meshing; 3) poor lubrication or wear of bearings. (4) Magnetic field strength of magnetic separator is weakened The reasons are: 1) the temperature is too high; 2) the sun is exposed; 3) the acid-base corrosion. It can be measured with a Gauss meter. The magnetic separator consists of a base, a lower magnetic system, a rotating cage, an upper magnetic system, a hollow shaft, a concentrate tank, and a transmission device. The mounting base measures its elevation and level with reference to the hollow bearing block. The positioning of the lower magnetic system is based on the base. The gap adjustment between the cage and the upper and lower magnetic systems must be accurate, and the gap limit deviation is 0+1mm.