The grinding mill belongs to the commonly used powder machinery, and its main faults are low powder output, motor heating, and increased energy consumption. Sometimes the grinding mill appears coarser or superfine powder size. No matter which kind of failure, it will increase the production cost of the enterprise, or directly affect the production. To facilitate customers, the list is made as follows.


Common faults and solutions of the grinding mill

Common faults	Causes and phenomena	Solutions
1. No powder or little powder with low output	①The airlock valve is not adjusted properly and the seal is not tight, causing powder to be sucked back. ②The scraper is worn out, and the material can not be shoveled. ③Clogged pipes, air leakage from pipes, and flange connections.	①Check and adjust the seal of the airlock valve. ②Replace the scraper. ③If the pipeline is blocked, clean it and unclog it; if it leaks, reseal it to prevent the dust from being sucked back.
2. The finished product is too coarse or too fine.	①Powder separator blade is worn seriously without classifying effect ②Improper powder separator speed. ③Improper fan airflow.	①Replace the powder separator blade. ②Adjust the speed of the powder separator appropriately. ③Adjust the inlet air volume by adjusting the rotating speed of the fan.
3. Mill current rises, machine temperature rises, and fan current drops.	①Overfeeding, air ducts clogged with powder. ②Poor pipeline exhausting and circulating airflow heating cause rising of the current and temperature of the main machine, as well as dropping of fan current.	①Reduce the amount of feeding, and remove accumulated powder in air ducts. ②Open the valve of the residual air duct, and control the humidity of the incoming material below 6%.
4. Grinding mills are noisy and use large vibration	①The feeding amount is small, and the grinding roller smashes the grinding ring. ②Hard material with a large impact, or no material layer. ③The grinding roller and ring are out of round and deformed seriously. ④Foundation bolts loose.	①Increase the feeding volume. ②Reduce feed size, increase feed density ③Replace the grinding roller and ring. ④Check and tighten the foundation bolts.
5. Grinding mill fan vibration	①Powder accumulates on the blades or the wear is unbalanced. ②Worn drive shaft or damaged bearings	①Remove the powder accumulated on the blades or replace the blades. ②Repair or replace the drive shaft and bearings.
6. Grinding mill gearbox heating	①The oil viscosity is so thick that the threaded pump won't hit it, causing the upper bearing to lack oil.	①Check whether the grade and viscosity of the oil meet the requirements of the manual's lubrication system table.
7. Powder separator oscillation	①Powder selecting blade accumulates powder, and the rotor is unbalanced. ②Powder separator shaft or bearing damage causing clearance.	①Remove the powder accumulated on the blades. ②Repair or replace the shaft or bearing of the powder separator and adjust the clearance.
8. Damage to the bearing of the grinding roller device	①Oil breakage or damaged seal ring. ②Lack of maintenance and cleaning.	①Timely refueling according to the specified time. ②Regular cleaning, and replacing oil seals.