Contact fatigue failure refers to the failure caused by alternating stress on the working surface of IKO imported bearing. Contact fatigue spalling occurs on the working surface of the bearing and is often accompanied by fatigue cracks.
It first occurs from the large Imported Bearing Iko alternating shear stress below the contact surface, and then extends to the surface to form different spalling shapes, such as pitting or pitting spalling, which is called shallow spalling.
Imported Bearing Iko
Contact fatigue failure
Due to the gradual expansion of the spalling surface, it often Imported Bearing Iko expands to the deep layer, forming deep spalling. Deep spalling is the fatigue source of contact fatigue failure.
2. Wear failure
Wear failure refers to the failure caused by the continuous wear of the metal on the working surface caused by the relative sliding friction between the surfaces.
Continuous wear will cause gradual damage to bearing parts, and eventually lead to the loss of dimensional accuracy of IKO imported bearings and other related problems. Wear may affect the change of shape, the increase of fit clearance and the change of working surface morphology,
may affect the lubricant or make it polluted to a certain extent, Imported Bearing Iko resulting in the complete loss of lubrication function, so that the bearing loses the rotation accuracy and even cannot operate normally.
Wear failure is one of the common failure modes of various bearings. Imported Bearing Iko According to the wear form, it can be divided into common abrasive wear and adhesive wear.
1) Instrument detection
It is only a convenient and reliable method to judge the running state of the bearing and whether it Imported Bearing Iko should be maintained or replaced by using a Ferrograph or SPM or a new vib05 detector.
For example, when using vibo5 detector, which is a newly designed machine state detection instrument based on microprocessor, it has the functions of vibration detection, IKO imported bearing state analysis and infrared temperature measurement.
It is easy to operate and Imported Bearing Iko automatically indicates the state alarm. It is very suitable for on-site equipment operation and maintenance personnel to detect the state of the equipment, find problems in time and ensure the normal and reliable operation of the equipment.
Using such an instrument can make full use of the working Imported Bearing Iko potential of the bearing, guarantee the bearing in time, and avoid faults. It is more suitable for young workers to make up for their lack of experience.
2) Manual detection
In places where the above instruments are not available, monitoring tools modified by equipment similar to medical stethoscope can be used for detection.
Experienced operators can also use tools such as round rods or wrenches to collide with the parts of the machine shell close to the bearing and use their ears to monitor the running sound of the bearing through the tools.
The normal running sound of IKO inlet shaft should be uniform, Imported Bearing Iko stable and not harsh, while the abnormal bearing running sound is intermittent, impact or harsh.
This method is suitable for experienced staff to operate, Imported Bearing Iko which mainly depends on the accumulation of staff experience.
Regular lubrication and maintenance of SKF Bearing to avoid failure
1. Grease lubrication
The re lubrication of SKF Bearing is carried out during the planned equipment shutdown and supplemented regularly. At the same time, the old grease is removed or squeezed out through the oil drain air.
Wipe the grease nipple clean before adding fresh grease. If there is no grease nozzle in the bearing box, open the bearing box cover or end cover to take out the old grease. After cleaning, add fresh grease of the same model.
2. Lubricating oil lubrication
Regularly check the oil level and quality of lubricating oil. Generally, the normal oil level should be within 1 / 3-2 / 3 of the equipment oil level window or mark. The oil replenishment mode is the oil cup,
and the displayed oil level only represents the oil replenishment capacity, while the oil level of the bearing box meets the operation requirements. If the oil level in the oil cup is lower than 1 / 4 of its total volume, oil replenishment can be considered.
Check and replenish oil methods. Take a small amount of lubricating oil as a sample and compare it with fresh lubricating oil. Competent units can consider oil quality test to ensure that the oil quality is qualified.
If the sample looks like a cloud, it may be the result of mixing with water, which is often called oil emulsification. At this time, the lubricating oil should be replaced.
If the sample becomes darker or thicker, it may indicate that the lubricating oil has begun to carbonize, and the old lubricating oil should be completely replaced. If possible, flush the oil circuit with fresh lubricating oil.
When replacing the lubricating oil, ensure that the new and old models of the replaced lubricating oil are the same, and supplement it to meet the required oil level.
Use the oil bath lubrication system. If the oil temperature is below 60 ℃ (140 ° f) and the lubricating oil is not polluted, replace the lubricating oil once a year. If the oil temperature is 60-100 ℃ (140-210 ° f),
the lubricating oil needs to be changed four times a year. If the oil temperature is 100-120 ℃ (210-250 ° f), the lubricating oil needs to be changed once a month. If the oil temperature is above 120 ℃ (250 ° f), the lubricating oil needs to be changed once a week.
Correct installation and maintenance is an important factor for the normal operation of SKF Bearing. At the same time, attention must be paid to maintaining the cleanliness of the bearing. The bearing must be protected from contamination by pollutants and moisture, and must be correctly installed and lubricated.
In addition, the design of bearing arrangement, the condition of oil seal, the form and replacement cycle of lubricant and special maintenance also play an important role, which must be paid attention to.
Common faults of imported bearings are as follows:
1. Tile surface corrosion: abnormal concentration of non-ferrous metal elements is found by spectral analysis; Submicron wear particles with many non-ferrous metal components appear in ferrography; The water content and acid value of lubricating oil exceed the standard.
2. Journal surface strain: there are ferrous cutting abrasive particles or black oxide particles in the ferrogram, and there is tempering color on the metal surface.
3. Journal surface corrosion: the spectral analysis found that the concentration of iron was abnormal. There were many submicron particles of iron in the ferrogram, and the water content or acid value of lubricating oil exceeded the standard.
4. Surface strain: cutting abrasive particles are found in the Ferrograph, and the abrasive particles are composed of non-ferrous metals.
5. Fretting wear of tile back: abnormal iron concentration is found by spectral analysis. There are many iron components, submicron wear particles, abnormal moisture and acid value of lubricating oil in the ferrogram.
Under the condition of liquid lubrication, the sliding surface is separated by the lubricating oil without direct contact, which can also greatly reduce the friction loss and surface wear, and the oil film also has a certain vibration absorption ability