In production, there is often a fever of rolling bearings. If the cause analysis is not clear, the treatment is not timely and the measures are inappropriate, it will take twice the effort and half the effort, and even lead to bearing burnout, gear reducer teeth beating and other malignant accidents. Following are some typical cases encountered in the process of production debugging. The specific problems in design, installation, lubrication, assembly and other links are analyzed and summarized for your reference.
1. There are congenital deficiencies in the design of bearing lubrication parts.
The excess fan at the kiln head of No. 1 kiln of our company had many bearing burning accidents in 2003 (the initial stage of commissioning). After on-site investigation, it was found that there was a problem in the oil mark design of the bearing seat. When the oil level is marked under the oil mark, the actual measurement shows that the lowest row of balls of the bearing has just touched the oil level. Only when the oil level is shown on the upper scale line, can it meet the operation needs. When the oil level approached the lower groove, the lubrication condition deteriorated. At first, the bearing temperature increased slowly. The field personnel did not pay enough attention to the alarm of bearing fever. Once the temperature rose to a certain extent, the bearing would rise sharply and burn out in a very short time. Therefore, incorrect oil labeling will cause misleading to inspection and maintenance personnel. After ascertaining the reasons, the refueling standard line was redrawn.
2. Lubricating oil pipes are blocked by foreign bodies
Because the lubrication management is not strict, containers are dirty or pipeline welding pickling is not standardized in the process of oil refueling and oil changing, which results in impurities such as welding slag rust entering the pipeline and blocking oil holes, which is quite common in earlier projects. The company's raw material mill reducer because the oil circuit is blocked burning bearings, the company's cement mill reducer is also blocked by cotton yarn caused by long-term high temperature bearings. In particular, TH company reducer high-speed axle bearing inspection oil volume, always can not see how much oil can be added to the high-speed bearing, etc. After thorough removal of the tubing with high-pressure air blowing, it was found that there were two thin cotton ropes blocked inside!
In addition, in the process of replacing reducer bearings, the company also found that the oil hole of the bearing eccentric sleeve was too thin (the oil hole of the eccentric sleeve could be one size larger than the oil hole diameter of the bearing itself), so the oil hole was enlarged. Because the bearings of all parts of the hard tooth surface reducer are generally lubricated by force at the dilute oil station, and the oil pipes at each lubrication point are in parallel, it is difficult to find the blockage phenomenon of individual oil pipes when observing the total amount of oil and return oil. Therefore, experienced maintenance personnel will carefully check the temperature of each oil pipe and judge whether the oil pipeline is unblocked according to the temperature difference of the oil pipes. Generally, the temperature of oil-free tubing is lower than that of other pipelines.
3. Lubricating oil (grease) deterioration or oil is not timely
The lubricating oil (or grease) used in rolling bearings has a certain working temperature. When the temperature is too high, the water and ash in the bearing seat will be seriously oxidized, emulsified and other deterioration, thus losing the lubrication effect and burning the bearing due to high temperature. In addition, the poor quality of lubricating oil (or grease) itself or the lack of timely refueling (grease) in operation are also common phenomena, such as rainwater entering into the roller bearing of belt conveyor, coal or raw meal entering into the rotary feeder bearing and Fuller pump bearing, which will cause the bearing temperature to rise or produce abnormal sound.
4. Scaling and clogging of coolers in lubricating pipelines, resulting in poor cooling effect
Especially in summer production, this problem is particularly prevalent. Individual manufacturers do not hesitate to increase or parallel series coolers to enhance the cooling effect. Because the scaling of high temperature fan cooler is serious, bearing temperature is too high frequency and frequent alarm has been encountered in various branches. The more effective treatment method is to carry out acid cleaning and scale removal of the cooler before summer every year.