Everyone in the process of using the ball mill will inevitably have a failure. The failure of the ball mill means that the output is reduced, and the failure of the machine can be solved as soon as possible. The following describes several common ball mill failures!
First, the preparation of the ball mill before commissioning
1. The ball mill cleans the inside of the workshop and removes all the tools for construction.
2. Inspection and cleaning of the ball mill equipment itself:
(1) Whether there are any items or debris in the ball mill;
(2) Whether there are any debris in the feed and discharge tweezers and in the suction pipe;
(3) Cleaning of the ball mill bearing and the outer cylinder of the ball mill;
(4) Clean the joint parts, ball mill bearings, reducer and motor exterior;
(5) The inside of the motor is blown with compressed air, and the inside of the motor is checked for any foreign matter.
3. Flush the oil pipeline, generally use 40# oil after filtration and 20% anti-rust agent to rinse. First remove the oil pipe leading to the equipment and seal it with a blind plate at the inlet of the equipment oil circuit. Use the temporary pipeline to connect the equipment inlet pipe to the collection and output oil pipe, flush it with the circulating oil pump, and check it on the fuel pipe oil filter net of the fuel tank until there is no debris in the filter purchase net, so that the flushing in the oil pipe is considered qualified. Then, the tubing is also flushed with a circulating oil pump and attached to the equipment.
4. Check the tightening degree of anchor bolts and lining bolts item by item. Check the power supply voltage and control device reliability. The ball mill removes the coupling bolts of the motor and the reducer, the reducer and the coupling of the ball mill, or the coupling member, so that each part can be rotated separately.
5. Before the ball mill is commissioned, the high-pressure oil pump is operated first. The ball mill uses the high-pressure oil film to lift the mill to form a float, reduce the torque of the ball mill, and then fill each bearing and lubrication part.
6. Check whether the cooling water pipe is blocked. Before the test run, open the cooling water pipe joint to the flushing pipe until the cooling water is clean.
Second, ball mill test run requirements
The test operation is performed in the order of the motor, the motor coupling reducer, and the reducer ball mill. China's cement machinery and equipment installation and construction acceptance of the temporary technical regulations "Building Regulations 7-62" stipulates that the motor is running for 4 hours, with a reducer running for 8 hours, with a ball mill running for 24 hours. The temperature of the main shaft and the transmission bushing does not exceed 55 °C, and the temperature of the rolling bearing of the reducer does not exceed 70 °C. At present, there is no clear regulation in foreign countries. After two or three hours of operation, after normal operation, temperature rise and vibration are kept within the specified range, and it is considered qualified.
Third, the ball mill in the trial run, often problems and treatments
1. When the energy-saving ball mill is running, there is a regular tapping sound, and the sound is very loud. Some of the lining bolts are not tightened, and the lining plate strikes the grinding cylinder when the ball mill rotates. According to the sound, the lining part is judged, and the loose bolt is found and tightened separately.
2, ball mill and motor bearing temperature rise, exceeding the regulations. If you try to test the bearing by hand or if the temperature is too high, check it from the following items.
(1) Check the lubrication points of each part, and the lubricating oil grade used is consistent with the factory manual.
(2) Check if the lubricating oil and grease have deteriorated.
(3) Check whether the lubrication pipeline is blocked or the lubricating oil does not directly enter the lubrication point, and the oil quantity is insufficient to cause heat.
(4) The side clearance of the bearing bush is too small, the gap between the bearing bush and the shaft is too large, and the contact point is too much to form a uniform oil film on the bearing bush.
(5) The rolling bearing grease is too much or too little, and the excessive formation of the rolling element agitates the grease to generate heat, and the heat is not easily dissipated. If the lubrication is too small, the amount of oil should be increased according to the regulations. The ball mill is generally suitable for 1/3 to 1/2 of the bearing clearance.
(6) The sealing device of the hollow shaft at both ends of the ball mill is too tight, or the sealing body iron member is directly in contact with the shaft.
The above problems are dealt with according to the reasons. Only the side clearance of the bearing bush is too small, and the ball mill or the bottom contact angle is too large. The grinding cylinder must be jacked up with the hydraulic jack, and the bearing bush should be pulled out from one side of the shaft. Scrape the tile.
3, ball mill reducer bearing heat:
In addition to checking the temperature rise of the ball mill bearing, check whether the vent hole of the reducer is blocked, and clear the vent hole.
4. After the motor is started with the reducer, vibration occurs. The main reasons are:
(1) The two-wheel clearance of the coupling is too small to compensate for the amount of turbulence caused by the self-seeking magnetic center of the ball mill when the motor is started.
(2) The alignment method of the coupling is incorrect, causing the two axes to be different.
(3) The coupling bolts of the coupling have no symmetrical tightening and the degree of tightening force is different.
(4), bearing outer ring activities.
Ball mill processing method: adjust the wheel gap according to the specified, so that the two axes are concentric. Tighten the coupling bolts of the coupling symmetrically with the same torque.
When the rotor is unbalanced, the ball mill pulls out the rotor and finds a static balance.
5. When the reducer drives the ball mill, huge vibration occurs:
(1), the balance shaft of the ball mill and the reducer, the axis is not in the straight line, the ball mill is caused by:
When the ball mill is installed with the lining, there is no secondary grouting, or the anchor bolts after the secondary grouting are not fastened. The hoisting machine rotates the grinding cylinder body, causing the grinding cylinder body to be displaced at one end, and the two axes are not in a straight line, so that The reducer drives the ball mill to generate vibration.
Ball mill processing method: to re-adjust, so that the ball mill axis and the reducer axis are on the same plane axis.
(2) The large ball mill is bulky and heavy, so that the foundation sinks; displacement occurs. The ball mill monitors the settlement point next to the foundation; observes it and finds that it is adjusted when it sinks.
6. The ball mill reducer operates abnormally:
The sound of the gearbox running normally should be even and smooth. The ball mill has a slight knocking sound like a gear, a hoarse friction sound, no obvious change during operation, and can continue to observe, find out the cause, stop the treatment, and if the ball mill is getting louder and louder, stop immediately for inspection.
It is worth noting that the balance wheel and the intermediate wheel of the reducer are not mounted at the specified meshing tooth height, which will cause the high-speed shaft pinion to drive the intermediate shaft large gear on one side, while the pinion of the intermediate shaft drives the balance wheel and the ball mill balance wheel. Turning again, the intermediate shaft on the other side is driven, so that the reducer does not form a rotation on both sides, and a click sound occurs, which is very dangerous.