Ball mills can be divided into energy-saving ball mills, overflow ball mills and lattice ball mills according to different ore discharging methods. Overflow ball mills are currently the most common mills used in most mineral processing plants.
Synchronous motor drive. The large-scale ball mill uses a low-speed synchronous motor to directly drive the pinion of the ball mill. The pinion then drives the large ring gear to rotate the ball mill. The advantages are high transmission efficiency, small floor space, easy maintenance and improved power factor of the power grid, but the synchronous motor sells at a higher price and requires a DC power supply.
Asynchronous motor gear reducer transmission. Large and medium-sized ball mills adopt asynchronous transmission, and the gear reducer drives the pinion gear and the large ring gear to drive the ball mill. The advantage is that the asynchronous motor is cheap, but a large set of large reducers are used. Asynchronous motor V-belt drive. The small ball mill uses an asynchronous motor to drive the pinion gear and the large ring gear through the triangle belt to drive the ball mill. The disadvantages are low transmission efficiency, large floor area and complicated maintenance.
There are three main transmission methods for ball mills produced abroad: the motor is driven by a pinion gear and a large ring gear. Central drive, that is, the motor drives the extension of the hollow journal through the reducer. The rotor of the motor is directly mounted on the extension of the cylinder or hollow journal, and the stator is fixed on the foundation, forming a so-called “gearless transmission”. At this time, the ultra-low speed synchronous motor is used, and its rotation speed is equal to the rotation speed of the ball mill, which is suitable for transmission power above 7500kw. If the feed of the ball mill is completed by the feeder. The ore feeder is fixed on the hollow journal of the ball mill and is driven together with the hollow journal. Commonly used ore feeders are drum-shaped, snail-shaped and combined ore-feeders.