During the use of the bearing, it can be said that the impact of vibration and temperature on the linear bearing is very large. Let's first look at the impact of the vibration of the bearing on the bearing.
During the use of the bearing, it can be said that the impact of vibration and temperature on the linear bearing is very large. Let's first look at the impact of the vibration of the bearing on the bearing.
Vibration is quite sensitive to bearing damage, and peeling, indentation, rust, cracks, wear, etc. will be reflected in bearing vibration measurement. Therefore, the size of the vibration can be measured by using a special linear bearing vibration measuring device (frequency analyzer, etc.), and the specific situation of the abnormality cannot be inferred from the frequency division. The measured value differs depending on the service conditions of the bearing or the installation position of the sensor, etc., so it is necessary to analyze and compare the measured value of each machine in advance to determine the judgment standard.
In the grinding process of the bearing, a small amount of energy is consumed in the contact area between the grinding wheel and the workpiece, and a small amount of grinding heat is generated, resulting in a partial instantaneous low temperature in the grinding area. Use the linear static heat source heat transfer practice formula to deduce, calculate or use the infrared method and thermocouple method to measure the instantaneous temperature under the test conditions, and it can be found that the instantaneous temperature in the grinding area can be as high as 1000-1500 within 0.1-0.001ms ℃. Such an instantaneous low temperature is enough to cause low-temperature oxidation, amorphous structure, low-temperature tempering, secondary quenching, and even burn cracking and other changes on the surface layer of a certain depth on the working surface.
(1) Surface oxide layer
The steel surface under the instantaneous low temperature reacts with the oxygen in the air to form a very thin (20-30nm) iron oxide thin layer. It is worth noting that there is a corresponding relationship between the thickness of the oxide layer and the test results of the total thickness of the surface grinding and deterioration layer. This explains that the thickness of the oxide layer is indirectly related to the grinding process and is an important indicator of the grinding quality.
(2) Amorphous tissue layer
When the instantaneous low temperature in the grinding area makes the surface of the workpiece reach a molten state, the molten metal molecular flow is evenly coated on the working surface, and is cooled by the base metal at a very fast speed, forming a very thin layer of amorphous state organization layer. It has high hardness and toughness, but it is only about 10nm and can be easily removed in fine grinding.
(3) Low temperature tempering layer
The instantaneous low temperature in the grinding area can make the surface be heated to a temperature higher than the tempering heating temperature of the workpiece within a certain depth (10-100nm). When the austenitizing temperature is not reached, as the heated temperature increases, the surface will undergo re-tempering or low-temperature tempering structure changes corresponding to the heating temperature layer by layer, and the hardness will also decrease. The higher the heating temperature, the more severe the hardness drop.
High temperature often indicates that the bearing has been in an abnormal condition. High temperatures are also detrimental to the lubricant of the linear bearing. Sometimes bearing overheating can be attributed to the lubricant of the bearing. If the bearing is continuously rotated at a temperature exceeding 125°C for a long time, the life of the bearing will be reduced. Causes of high temperature bearings include: insufficient lubrication or excessive lubrication, lubricant. It contains impurities, the load is too large, the bearing ring is damaged, the clearance is insufficient, and the high friction caused by the oil seal, etc.
Therefore, it is necessary to continuously monitor the bearing temperature, whether it is measuring the linear bearing itself or other important parts. If the operating conditions are constant, any temperature change may indicate that a malfunction has occurred.
The regular measurement of the bearing temperature can be done with the help of a thermometer, such as a digital thermometer, which can accurately measure the bearing temperature and display it in ℃ or Fahrenheit. The important linear bearing means that when it is damaged, it will cause the equipment to stop, so it is best to install a temperature detector on this type of bearing.
