Causes and solutions of motor failure of roller press granulator


Roller press granulator is commonly used in 1-2t/h NPK fertilizer production line. In the actual production, some small problems may lead to the failure of the extrusion granulator and affect the operation of the whole production line. It is an important fertilizer granulator machine in compound fertilizer production equipment. This paper introduces the common faults of the motor of the double roller extrusion granulator and how to solve them.

Main motor system fault

1. Main motor torque is too high or too low;
2. Main motor speed is too low;
3. The bearing temperature of main motor is too high;
4. The winding temperature of the main motor is too high;
5. The inlet and outlet temperature of the water-cooled cooler of the main motor is too high;
6. The outlet flow of main motor bearing lubricating oil pump is too low;
7. The outlet pressure of main motor bearing lubricating oil pump is too low;
8. The water leakage of the main motor water-cooled cooler is too high.
double roller press granulator

Method to solve the motor fault of double roller press granulator

1. High torque of main motor

The main motor bearing will be damaged and the torque will be too high due to the fault of oil lubrication system, poor alignment of the output shaft of main motor and the inlet and outlet shaft of gearbox, vibration of motor and clutch, etc. In addition, excessive feeding load or poor melting of materials will also lead to high torque of main motor.
  • Regularly check and clean the lubricating oil system, measure the main motor bearings with a vibration measuring instrument and infrared thermometer and form a trend chart. If the trend value is exceeded, determine whether the main motor idling current value or power value exceeds the specified value, and determine whether the bearing should be replaced.
  • Regularly check the alignment between the output shaft of the main motor and the input shaft of the gearbox. The alignment must be checked after running for three months after the first drive or bearing replacement. Conduct electrical test inspection to determine the cause of rotor imbalance; perform vibration speed test on the clutch, and if it exceeds the specified value, the dynamic balance should be readjusted.
  • Regularly check the cylinder heating and cooling system to ensure that the material is heated and melted evenly. If the power curve of the main motor and the melt pressure curve increase instantaneously when the extruder starts, it indicates that the feeding amount of the feeding system is too large instantaneously, and the feeding amount should be reduced.

2. Main motor torque is too low

The main motor torque will be too low if the feeding system fails to make the twin-screw idle.
Check and judge whether the additive system or the main material cutting system is in fault, and clean the blocking points.