The vacuum degree of the oil return pipe of the ultrafine vertical mill determines the oil level in the ultrafine vertical mill cavity. In order to keep the oil level in the ultrafine vertical mill relatively stable, the adjustment of the vacuum degree and pressure must be cautious. It is directly related to the lubrication state of the ultrafine vertical mill bearings.

If the oil pressure is too high, the oil level in the ultrafine vertical mill will rise, and the oil quantity will be too high, which will easily cause oil leakage of the ultrafine vertical mill and even damage the oil seal; if the oil pressure is too low, the oil quantity in the ultrafine vertical mill will be low or lacking, and insufficient lubrication will easily damage the ultrafine vertical mill bearings. . Generally, the adjustment range of vacuum is between -0.10 and -0.35bar.