Firstly start up the motors of the air lock of each discharger on the grinding machine, and then the air compressor of the pulsed dust collector, and then start up the motor for grading impeller, high pressure fan and main motor in turn. Only when the main motor runs stably, the motor of the screw feeder can be started up. Prior to starting up the fan, firstly close the air gate of the exhaust system, and then start the fan, finally open the air gate till the fan goes into normal run.
Firstly adjust the motor of the screw feeder to the minimum rotating speed, and then slowly increase the rotating speed of the motor according to the current of the motor for grinding; adjust the motor to a proper rotating speed, keep the current of the motor for grinding within the rated current range, and keep it run with an optimal load.
Control the particle size by changing the rotating speed of the grading impeller and adjusting the air volume.
When the grading impeller of the grinding machinery runs at a higher rotating speed, the graded particle size (i.e. particle size of finished product) is smaller, contrarily the particle size is bigger. The particle size of finished product can also be controlled by adjusting the volume of air flowing across the fan and changing the grading positions; when the volume of air flowing across the fan is higher, the particle size of finished product is bigger, when the volume of air is lower, and the particle size is smaller.
The feeding amount also varies with the change of particle size of the finished product. When increasing the rotating speed of the grading impeller or reducing the air volume, the particle size of finished product will become smaller, so the ground materials retention in the grinding machines as well as the current values of the motor for grinding and the motor for high pressure fan in the pneumatic conveying system will increase, vice versa. Therefore, the feeding amount will decrease or increase correspondingly as well. During the production, it is necessary to adjust the particle size of finished product and the feeding amount under the condition of that the motor for grinding and the motor for the high-pressure fan cannot run with exceeded current.
The stop sequence of the equipment is opposite to the startup sequence. That is, firstly close the gate under the grinding bin, and then shut down the motor for feeding, the fan and the motor for grading impeller, finally shut down the motor for grinding and the motor for the air lock.
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