Main bearing failure management of millDate: 2019-10-22 Views:
The main bearing of cement mill will break down for various reasons. Once the main bearing breaks down, production will be affected and economic losses will be caused.Main bearing failure management of mill,This paper mainly introduces the sealing method and fault diagnosis and treatment.
1. Main bearing seal of the mill
The traditional main bearing of grinding machine adopts wool felt ring seal, which is easy to be worn and the seal is not reliable.Practice has proved that dust particles mainly enter into the main bearing through the gap between the worn felt-wool ring and the hollow shaft.The radial labyrinth seal is used to improve the seal of main bearing.
Use the original steel car two seal rims, one male, one female, male and female rims according to radial labyrinth sealing needs corresponding circular labyrinth slot, then sealed the male and female rims were installed on the grinding machine Lord bearing cover and the hollow shaft, (before the installation in the labyrinth slot buttered and to reduce friction, and have certain sealing effect).In this way, the sealing steel ring fixed on the main bearing cover of the mill is stationary, while the sealing steel ring fixed on the hollow shaft runs together with the hollow shaft to prevent dust particles and other sundries from entering the main bearing of the mill by using the sealed labyrinth groove.Practice shows that the sealing effect is very good and the operating rate of the bearing bush is greatly improved.
2. Judgment and treatment of operating faults of main bearing of the mill
General main bearing operating failures mainly include the following:
(1) lubricating oil temperature gradually increases
The outer surface of the hollow shaft neck of the mill is formed with a babbitt stick mark. The deep mark can reach about 2mm, and the density is uneven.The main reason is that the grinding machine's hollow shaft journal is not smooth enough, so that the tile surface contact point is affected by shear stress, resulting in a large area of strain (shear failure).The grain of babbitt alloy is pasted on the surface of the hollow shaft journal, and when the hollow shaft is transferred to the upper part, it meets the cold oil and is treated cold, thus improving the hardness.At the same time, after the hollow shaft with babbitt particles is rubbed by cyclic operation, the lubricating oil temperature of the main bearing of the grinder increases gradually to produce high temperature.At this time, the bearing bush should be pulled out, scratch the surface of the tile again, striation too deep, also should be welded homogenous babbitt alloy.
(2) high temperature appears on one side of the bearing bush.
This is because of the adjustment fault of the tile base, which makes the tile surface contact with the hollow shaft neck in small area and the static load becomes larger.At this time to lift the grinding machine barrel, check the contact between the spherical tile back and the tile base, if necessary, re-grinding the tile base and the tile back, so that it can adjust the center freely.At the same time, it is necessary to scrape the tile surface again, scrape off the oxide layer completely, and polish the hollow shaft journal with whetstone.
(3) when the temperature rises, the spindle is grey and shiny with adhesion when there is t
This is due to the local high temperature tile surface and glue caused by, at this time should be scraping the bearing bush;Sometimes spindle bright, this is due to poor oil quality, the oil caused by more impurities, should be changed oil.
(4) the oil temperature is high, but there is no babbitt alloy adhesion phenomenon.
The reasons may have the following aspects: first, less lubricating oil supply and low viscosity, can not form oil film;Second, or poor oil quality;Third, the grinding tile did not meet the standard requirements, the gap is too small;Fourth, the cooling water of the shaft bush is not smooth.The oil can be changed, the tile can be scraped again and the cooling water can be unblocked.
The failure of the cement mill is largely due to the poor lubrication of the main bearing of the mill.It is very important to improve the sealing way of the main bearing and take reasonable lubrication measures for the normal operation of the mill.