The stable operation of equipment is the most important factor in guaranteeing the economic efficiency of processing plant. Through a long period of operation, most processing plants met various problems in ball milling process. They influence the normal operation of processing plants, and also damages the economic efficiency of processing plants. What are the common problems in the daily ball milling process? And how can we deal with them? In this passage, we are going to focus on three common problems in ball milling, and analyze the reasons and countermeasures.
For some ball mill, the feeding amount is far less than the designed capacity. If the feeding amount is over a certain limit, large amount of gravels are thrown out from the throat in ball milling process. It increases energy consumption and labor intensity.
Reasons and countermeasures:
(1)The feeding particle size is oversized(20mm over-designed size)
Oversized particles bring extra burden to ball mill, and some supersize particles are not easy to be broken by steel balls. It reduces the ball mill capacity and increases energy consumption. Therefore, in ball milling processing, the operator of ball mill should monitor the feeding size closely. If the particle size is over the designed limit, feeding should be stopped or reduced, and take relative measures to guarantee the feeding particle sizes.
(2)Unsatisfied steel ball filling amount
Because of the long period operation of ball mill, the steel balls are badly worn, and reducing the diameter and striking force. If the steel ball filling is not timely, it leads to the unsatisfied capacity of ball mill. Therefore, to maintain a certain filling coefficient and diameter of steel balls, qualified steel balls should be filling in termly according to the electric flow and accumulated grinding materials amount.
(3)The breakage of ball mill inner liner
Complete ball mill cylinder liner can increase the coefficient of friction between steel balls and liner. It is advantage for the lifting of steel balls and materials. It also increases the capacity of ball mill. If the liner is badly worn, a large relative sliding is between steel balls and liners. Therefore, more energy is consumed in the friction between steel balls and liner, instead of lifting steel balls. The capacity largely reduced. If the inner liner is damaged or fallen off, an obvious crashing sound can be heard. If it happens, the ball mill should be stopped as soon as possible, and the damaged liner should be dealt to avoid larger damage of ball mill liner.
During the normal ball milling process, pulp is thrown out from throat with small stones.
(1)Imbalance of water-material ratio in ball mill
The water amount in ball mill cylinder is an important index in ball milling process. It reflects the carrying energy of particle materials in ball mill. Therefore, the water amount through ball mill cylinder is corresponding with the material throughput of ball mill, which should be controlled in a suitable limit. The water in ball mill is mainly the slurry carrying water and the underflow of hydrocyclone. The underflow amount of hydrocyclone is usually stable, if the hydrocyclone underflow sand nozzle of hydrocyclone. If the underflow sand nozzle is damaged, the working condition of hydrocyclone is changed, which increases the underflow water and reduces the overflow water amount. It also increases the water amount of ball mill.
Therefore, during the ball milling process, we should notice and check the weariness of hydrocyclone sand nozzle. Guaranteeing the water-material is in a normal limit. It can guarantee the normal throat of ball mill, and also reduces the pulp thrown-out a labor intensity.
(2)The sieve pore diameter of cylindrical screen at the throat of ball mill and the cleanness of throat strainer
If the sieve pore diameter is over large, the coarse material can increase the degree of wear of pump and hydrocyclone. It even causes the blocking of pump. If the sieve pore diameter is too small, the sieve is easy to jam, which also causes the pulp thrown out form throat. Besides, in the normal ball milling process, there are some impurities in the high concentration pulp. It also causes the jam of sieve of ball mill throat filter and even the pulp thrown out. Therefore, we should choose a reasonable sieve pore size, and keep clean of sieve cleanness.
In ball milling process, steel balls are thrown out from throat with small stones.
The reason why steel balls thrown out from throat is the over high material level in the ball mill. The reasons of over high material level in ball mill are three factors. The first is the water-material ratio reduces, which reduces the carrying capacity of water, leads to the rise of material level. The second is the over larged feeding material size. It increase the residence time in ball mill of material. The third is too many steel balls in the ball mill. Therefore, these factors should be strictly controlled in ball milling process.
The above are three common problems, reason and countermeasures of ball mill. The stable and high-efficiency operation of equipment need reasonable equipment according to the mineral processing flow, and daily maintenance as well. We suggest consulting ball mill selection with the manufacturers, choosing the reasonable equipment suitable for the processing flow and guaranteeing the production efficiency and economy of processing plant.
None ... [more]