Fault cause and treatment of vertical grinding block materialDate: 2019-07-11 Views:
Vertical grinding block material is divided into two kinds of material block into the mill and out of the mill.
1.1 feeding mill block material, judging from operating parameters of central control
(1) the vibration of the mill continues to fluctuate at a higher level.This vibration is different from the small amplitude vibration in normal operation, and it is different from the sudden vibration (high peak value in an instant) caused by the iron input in the grinding chamber. It keeps vibrating at the amplitude 1 ~ 2 mm/s higher than the normal vibration value.
(2) the differential pressure of the mill decreases, the load of the powder separator decreases, the temperature of the outlet of the mill increases, the three-channel lock air valve or rotary feeder stops, and the vibration of the mill continues to fluctuate at a higher level.
The above two cases of treatment measures: immediately clean up the grinding chute plug phenomenon.
(3) block the feeding chute on the upper part of the three-channel lock air valve.Rainy season is more, when the grinding material is wet, the material is easy to bond in the three lock air valve chute into the grinding, resulting in the three lock air valve upper feeding chute block material, serious will cause shutdown.
Treatment measures: install air cannon at the three valve feeding chute, and conduct preheating and drying of materials from the hot air pipe of kiln tail waste gas to the three valve locking air feeding chute.In addition, the post strengthens the patrol inspection, hitting the three locking air valve feeding chute with hammer every period of time to prevent the materials hanging on the wall in the pipeline.
(4) the valve plate of three air lock valves is stuck.Three-way lock air valve plate material is due to the three-way lock air valve plate and the side wall of the gap is too large, so that individual blocks stuck between the plate and the side wall.
Treatment: weld the baffle on both sides of the three-way valve plate. There are few blocks stuck between the three-way valve and the wall plate, thus reducing the chance of stuck materials.
(5) rotary feeder adhesive.When the grinding material is wet, it is easy for the material to bond in the rotary feeding device, which leads to the slippage at the rotary feeding device.
Treatment measures: RM vertical mill designs the rotary feeder blade as hollow and draws hot air from the hot air pipe of kiln tail waste gas. The wet material near the blade surface is preheated and dried, which greatly reduces the adhesion phenomenon.
(6) clamping of rotary feeder.It is the same with the valve plate of the three-way lock air valve, because the gap between the rotary feeder blade and the side wall is too large, so that individual blocks are stuck between the blade and the side wall.
Treatment measures: check the gap between the blade and the side wall of the rotary feeder frequently. If the gap is too large due to serious wear, timely repair welding shall be carried out to ensure that the blade of the rotary feeder and the side wall have no friction, so as to reduce the stuck material phenomenon.
1.2 grinding chute blocking material
(1) abnormal increase of power of main motor by 30%.Generally, the grinding pressure, bed thickness and the corresponding power of main motor fluctuate in a small range.The higher the thickness of the bed, the greater the power of the main motor.If the bed thickness is relatively thin (within the normal range) and the main motor power is higher than the normal value, it indicates the possibility of accumulation in the scraper cavity.So the power of main motor is the most sensitive parameter of blocking material.
(2) the differential pressure of the mill increases, the load of the separator increases, the outlet temperature of the mill decreases, and the vibration of the mill continues to fluctuate at a higher horizontal line.
Measures to deal with the above two conditions: open the manhole door on the grinding chute (at this time the air leakage is small) to clear the blockage, if not, stop grinding immediately and thoroughly clean the blockage.
(3) nozzle ring blocking material.When the grinding material is very wet, humidity is more than 3%, mixed with large materials, insufficient air volume, feed, such as wind speed instability produces too much nozzle ring jams, jams, uneven millstone around wind speed, air volume, mill feeding bed is not flat, produce large vibration (RM type vertical mill nozzle ring, unlike other mill type structure, thus not jam).
Treatment measures: stop grinding and clean up, when starting grinding again, pay attention to reduce the bulk material into grinding, increase the air volume, reduce the feeding, keep the working condition of the mill stable, prevent the nozzle ring from blocking.