For a long time, ball mills have been widely used in walls, floors, bricks, and chemical factories to grind ceramic raw materials. It generally adopts simple power frequency control, which is easy to cause excessive grinding of materials. The required grinding cycle is long, the grinding efficiency is low, and the work per unit product The consumption is large, the starting current is large, the impact on the equipment and the power grid is great, the production and maintenance of mechanical equipment are also large, and the power loss is quite amazing, which will inevitably bring a lot of unnecessary trouble and serious damage to the manufacturer. Waste of resources, so with the development of the social economy and the expansion of the production scale of enterprises, the disadvantages of direct industrial control ball mills have been fully exposed, and have seriously hindered the rapid development of various industrial enterprises.
This prompts people to develop a ball mill with smooth start, high grinding efficiency, large output, and low energy consumption—the frequency conversion control ball mill.
Main structure
Ceramic industry ball mill is mainly composed of transmission device, cylinder device, feeding device, unloading device and electrical control device.
Transmission
Ceramic industrial ball mills have a large loading capacity and require a lot of power consumption. Therefore, ceramic industrial ball mills usually use 1 to 2 high-power motors with tens of kilowatts (hundreds of kilowatts) to jointly drive hard-toothed cylindrical gears through hydraulic couplings. The reducer drives the cylinder to rotate through a pair of gears or pulleys, so as to achieve the effect of grinding materials.
Working Principle:
The ball mill is composed of feeding part, discharging part, rotary part, transmission part (reducer, small transmission gear, motor, electric control) and other main parts. The ceramic industry has a horizontally placed cylinder, which is divided into 3 to 4 grinding chambers by a partition (a circular plate drilled with many small round holes – a sieve plate), and each grinding chamber is equipped with a grinding body of a certain shape and size. , when the cylinder rotates, the material and grinding body are lifted to a certain height by the cylinder under the action of friction and centrifugal force, and then fall down along an approximate parabolic trajectory under the action of gravity to impact and grind another part of the material at the bottom of the cylinder. And produce a certain axial movement to promote the grinding and mixing of materials evenly.
Electrical Basic Controls
Ceramic industrial ball mills are low-speed and heavy-duty equipment with large loading capacity and large starting torque. Therefore, ceramic industrial ball mills are usually started by an additional starter motor impact start or soft start device, which has a large impact on the power grid. The torque is reduced, so there is a lot of room for energy saving.
Retrofit plan:
According to the problems existing in the original working conditions and combined with the requirements of the production process, the modified ball mill system should meet the following requirements.
(1) The manufactured equipment must have sufficient starting torque to meet the requirements of large loading capacity of the ball mill, and ensure that the equipment runs smoothly under the condition of frequency conversion to ensure that the motor has constant power characteristics.
(2) Transform the original drive system of the ball mill by using the frequency conversion speed control system to meet the normal operation of the ball mill at low speed, ensure normal process control technology, prolong the service life of the ball mill and the motor, and reduce maintenance.
(3) The equipment after transformation can realize functions such as automatic control, manual/power frequency and fault self-switching, and can overcome the rebound voltage caused by the large inertia of the ball mill, effectively ensuring the normal operation of the equipment.
Advantages after equipment transformation
(1) The drive system of the ball mill has been improved by using frequency conversion speed regulation technology, which meets the characteristics of low-speed operation and large starting torque of the ball mill, and realizes the continuous adjustment of the running speed of the ball mill. There is no inrush current when the motor starts, the starting torque is sufficient, and the protection function is perfect. The process is guaranteed, the quality is controlled, and the maintenance cost is saved.
(2) According to the needs of the working situation, change the transmission ratio to A and set the given frequency of the inverter to B (less than 50HZ), the operating voltage to C (380V), and the operating current to D (less than the industrial frequency) during normal operation. ), the average annual power consumption of the transformed system is E degrees (C*D*working hours per day*360). Before the system transformation, the power frequency was 50HZ, the operating current was 180A and the operating voltage was 380V. The average annual power consumption was F (90*daily working hours*365) degrees, and the power saving rate was (1-E/F)%.
For a long time, ball mills have been widely used in walls, floors, bricks, and chemical factories to grind ceramic raw materials. It generally adopts simple power frequency control, which is easy to cause excessive grinding of materials. The required grinding cycle is long, the grinding efficiency is low, and the work per unit product The consumption is large, the starting current is large, the impact on the equipment and the power grid is great, the production and maintenance of mechanical equipment are also large, and the power loss is quite amazing, which will inevitably bring a lot of unnecessary trouble and serious damage to the manufacturer. Waste of resources, so with the development of the social economy and the expansion of the production scale of enterprises, the disadvantages of direct industrial control ball mills have been fully exposed, and have seriously hindered the rapid development of various industrial enterprises.
This prompts people to develop a ball mill with smooth start, high grinding efficiency, large output, and low energy consumption—the frequency conversion control ball mill.
Main structure
Ceramic industry ball mill is mainly composed of transmission device, cylinder device, feeding device, unloading device and electrical control device.
Transmission
Ceramic industrial ball mills have a large loading capacity and require a lot of power consumption. Therefore, ceramic industrial ball mills usually use 1 to 2 high-power motors with tens of kilowatts (hundreds of kilowatts) to jointly drive hard-toothed cylindrical gears through hydraulic couplings. The reducer drives the cylinder to rotate through a pair of gears or pulleys, so as to achieve the effect of grinding materials.
Working Principle:
The ball mill is composed of feeding part, discharging part, rotary part, transmission part (reducer, small transmission gear, motor, electric control) and other main parts. The ceramic industry has a horizontally placed cylinder, which is divided into 3 to 4 grinding chambers by a partition (a circular plate drilled with many small round holes – a sieve plate), and each grinding chamber is equipped with a grinding body of a certain shape and size. , when the cylinder rotates, the material and grinding body are lifted to a certain height by the cylinder under the action of friction and centrifugal force, and then fall down along an approximate parabolic trajectory under the action of gravity to impact and grind another part of the material at the bottom of the cylinder. And produce a certain axial movement to promote the grinding and mixing of materials evenly.
Electrical Basic Controls
Ceramic industrial ball mills are low-speed and heavy-duty equipment with large loading capacity and large starting torque. Therefore, ceramic industrial ball mills are usually started by an additional starter motor impact start or soft start device, which has a large impact on the power grid. The torque is reduced, so there is a lot of room for energy saving.
Retrofit plan:
According to the problems existing in the original working conditions and combined with the requirements of the production process, the modified ball mill system should meet the following requirements.
(1) The manufactured equipment must have sufficient starting torque to meet the requirements of large loading capacity of the ball mill, and ensure that the equipment runs smoothly under the condition of frequency conversion to ensure that the motor has constant power characteristics.
(2) Transform the original drive system of the ball mill by using the frequency conversion speed control system to meet the normal operation of the ball mill at low speed, ensure normal process control technology, prolong the service life of the ball mill and the motor, and reduce maintenance.
(3) The equipment after transformation can realize functions such as automatic control, manual/power frequency and fault self-switching, and can overcome the rebound voltage caused by the large inertia of the ball mill, effectively ensuring the normal operation of the equipment.
Advantages after equipment transformation
(1) The drive system of the ball mill has been improved by using frequency conversion speed regulation technology, which meets the characteristics of low-speed operation and large starting torque of the ball mill, and realizes the continuous adjustment of the running speed of the ball mill. There is no inrush current when the motor starts, the starting torque is sufficient, and the protection function is perfect. The process is guaranteed, the quality is controlled, and the maintenance cost is saved.
(2) According to the needs of the working situation, change the transmission ratio to A and set the given frequency of the inverter to B (less than 50HZ), the operating voltage to C (380V), and the operating current to D (less than the industrial frequency) during normal operation. ), the average annual power consumption of the transformed system is E degrees (C*D*working hours per day*360). Before the system transformation, the power frequency was 50HZ, the operating current was 180A and the operating voltage was 380V. The average annual power consumption was F (90*daily working hours*365) degrees, and the power saving rate was (1-E/F)%.
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