IKO bearing maintenance

1. Maintenance, inspection, and abnormal handling of IKO bearings In order to maintain the original performance of IKO bearings in good condition for as long as possible, maintenance, inspection, and accident prevention are required to ensure the reliability of operation and improve productivity. Economic. Maintenance is best carried out on a regular basis in accordance with the operating standards for the mechanical operating conditions. The contents include monitoring of operating conditions, replenishment or replacement of lubricants, and inspections for periodic disassembly.

As a maintenance item during operation, there are rotary sounds, vibration, temperature, and state of lubricant of IKO bearings.

2, IKO bearing damage and countermeasures Generally, if the IKO bearing is used correctly, it can be used until the fatigue life is reached. However, there will be accidents that are prematurely damaged and cannot be used. This early damage, as opposed to fatigue life, limits the quality of what is known as a fault or accident. Many of them are caused by inadvertent installation, use, and lubrication, and foreign objects intruding from the outside are insufficiently studied for the thermal effects of the shaft and the outer casing.

Regarding the damage state of the IKO bearing, for example, the jam of the ferrule rim of the roller IKO bearing can be considered as a cause of insufficient lubricant, unsuitability, defects in the oil supply structure, foreign matter intrusion, IKO bearing installation error, shaft If the deflection is too large, there will be coincidences of these reasons.

Therefore, it is difficult to know the true cause of the damage by investigating only IKO bearing damage. However, if you know the IKO bearing's use of machinery, the conditions of use, the structure around the IKO bearing, and understand the situation before and after the accident, combined with the damage state of IKO bearings and several reasons, it can prevent similar accidents from happening again.

For more information and purchase please visit: https://www.supplyforever.com

Maximize the service life of eccentric bearings

In addition to the quality of the product itself, the life of the eccentric bearing has some important factors.

First, the bearing selection stage, need to consider many factors (such as: load, hardness, operating environment, etc.), a good eccentric bearing design will first make the bearing reach its maximum life value.

Second, the correct storage, eccentric bearings should preferably be stored in their original packaging before installation. It needs to be left in a clean, moisture-free, relatively constant temperature environment. Rolling bearings should be kept away from dust, water and corrosive chemicals. Shaking and vibration can permanently damage the mechanical properties of the bearing, so vibration should be avoided during handling and storage. Generally, the bearings should be stored horizontally. Some heavy bearings will be deformed due to their own weight after being placed vertically for a long time! Also, greased (or sealed) bearings require special care because the density of the grease changes over time. When the bearing is used for the first time, there will be a certain degree of rotational noise. Therefore, the shelf life of such bearings should be controlled on the principle of first in, first out!

Third, clean, this is very important for rolling bearings. The rotating surface of the eccentric bearing ring is very smooth and very sensitive to damage caused by contaminants. Particulate impurities can be excessively crushed by the rolling elements to create partial pressure in the bearing, which can eventually lead to permanent material fatigue.

Fourth, full equipment and re-installation, the bearings should be carefully installed and disassembled with appropriate tools (refer to the bearing disassembly series video). You should choose the right tool! Industry experts estimate that 16% of bearings fail prematurely due to incorrect installation. Generally speaking, in general, a proper bearing mounting device is adopted. But in maintenance or replacement work, the environment is diverse! It is recommended that you read the relevant drawings, maintenance manuals and product manuals carefully. The components of the bearing should also be kept absolutely clean!

5. Careful installation and disassembly. I have talked about the installation of eccentric bearings many times before. (If you have similar problems, there are some articles on bearing installation.) Here is a brief summary: 1. Do not apply mounting force on the rolling elements. This can easily lead to local overloading of the rolling element and the contact surface of the race, thereby premature failure of the guide bearing. 2, do not use any hard tools (such as hammers, screwdrivers, etc., I have seen too many "hard" installation with these two tools, too strong) directly knock on the bearing surface, which will cause the bearing ring to break or break. 3. The general bearing will not be removed from the equipment, only the larger bearing will be removed due to preventive maintenance. During the disassembly process, the correct tool should be used first, to ensure that adjacent components are not damaged!

For more information and purchase please visit: https://www.supplyforever.com

Disadvantages of gas lubricated bearings

  (1) Low carrying capacity

Compared with similar oil-lubricated bearings, gas-lubricated bearings have a bearing capacity of about one to two orders of magnitude lower. According to the bearing capacity per unit area, oil-lubricated bearings are generally (0.5 to 2) MPa, while gas-lubricated bearings are only (0.02 to 0.04) MPa.

(2) Poor reliability

On the one hand, gas-lubricated bearings are prone to instability, and common air hammer vibrations and eddy instability occur. On the other hand, gas-lubricated bearings are stuck, hung or bitten.

(3) High manufacturing precision and expensive construction

Since the gas film is very thin, generally between a few micrometers and several tens of micrometers, the manufacturing precision of parts is required to be high, and the cost is increased. In addition, there are special process requirements such as processing spiral grooves, orifices and porous materials, which increases manufacturing difficulty and cost.

(4) demanding working conditions

Gas lubricated bearings require a high clean working environment and strict adherence to operating procedures to ensure proper bearing operation and no accidents. To this end, its widespread application and commercialization have been limited to a certain extent.

For more information and purchase please visit: https://www.supplyforever.com

Reasons for damage to diesel engine bearings

There are 7 major reasons for diesel engine bearing damage.

First, there is a lack of lubricant. The reasons include: no new oil is added after the oil is discharged; the crankcase screw plug leaks the oil due to the vibration loss; the filter block is blocked, the return valve spring is invalid, the blisters on the cylinder oil passage or the process hole are clogged off, the bearing bush is seriously worn, and the bearing bush is on the bearing. The oil hole is not aligned with the oil supply hole on the tile seat or the upper and lower tiles are incorrectly installed, the fuel pump plunger is worn and leaking, the injector is poorly atomized, and the diesel oil leaks into the crankcase, etc., so that the lubricating oil is thinned until Lack of oil and "burn" injuries.

Second, the lubricating oil is not clean. Reasons include: oil contains a lot of metal abrasives, dust or mechanical impurities.

Third, the lubricant grade does not meet the requirements of the specification.

The fourth is improper use of maintenance. The reasons include: the overload causes the bearing alloy to break and fall off, indentation on the bearing raceway, and even the inner and outer rings are broken; the axial clearance of the tapered bearing is too large, and the wheel collides when rolling on the rough road, so that the rolling element is pressed outside the bearing. The circle is broken; the calcium-based grease is not added once every 10~12h.

The fifth is the manufacturing defects of the bearing. Reasons include: deformation of the retainer, relative deflection of the inner and outer rings, skew of the rolling elements, and the like.

Sixth is poor preservation. Reasons include: poor rust prevention or exceeding the oil seal period without re-grinding; or rubbing with rust to reduce the accuracy, bumping or falling.

Seven is improperly installed. The reasons include: hammering the ring with a hammer and causing cracks; knocking the bearing with a punch causes the bearing to collapse; the seat is damaged by the shock wave and the other race, and the hard knocker causes the retainer to deform; the two bearing centerline The straightness error is too large, which causes the needle roller, the roller and the inner and outer rings to be subjected to a large pressure, resulting in premature fatigue damage of the bearing; the bearing is biased or forced to cause damage to the inner ring; the bearing is mounted to the outer diameter of the bearing outer ring. In a much smaller hole, the outer ring is deformed or broken, and the bearing rotation is stuck; the inner ring hole of the bearing and the journal or the outer ring of the bearing and the hole are loosely fitted, resulting in shaft deflection, poor gear meshing and damage to the bearing; assembly The error of the ruler chain causes the pre-stress of the bearing to be too large; the crankshaft journal taper is out of tolerance, the bearing bush is out of round, the incorrect press fit and the center line of the connecting rod are out of adjustment, etc., the bearing bush is damaged, the tapered journal and the bearing bush are asked. If the gap at one end is too large, the bearing bush is eccentrically worn, resulting in high temperature and increased wear.

For more information and purchase please visit: https://www.supplyforever.com

Regular lubrication and maintenance of SKF bearings to avoid failure

1, grease lubrication
Relubrication of SKF bearings is best carried out during planned equipment downtime and is periodically replenished, while removing old grease or extruding old grease through the drain. Wipe the grease fittings clean before adding fresh grease. If the bearing housing does not have a grease fitting, the bearing housing cover or end cap should be opened to remove the old grease and, after cleaning, replenish the same type of fresh grease.
2, lubricating oil lubrication
Regularly check the oil level and oil quality of the lubricating oil. Under normal circumstances, the normal oil level should be within the range of 1/3-2/3 of the equipment oil level window or mark. The oil filling method is oil cup, the oil level shown only represents the oil replenishing capacity, and the bearing tank oil level is to meet the operation requirements. The oil level in the oil cup is less than 1/4 of its total volume.
Check and replenish the oil method, take a small amount of lubricating oil as a sample and compare it with fresh oil. The competent unit can consider the oil quality test to ensure the oil quality is qualified. If the sample looks cloudy, it may be the result of mixing with water, which is commonly referred to as oil emulsification. At this point, the lubricant should be replaced.
If the sample is darkened or thickened, it may indicate that the lubricant has begun to carbonize and the old lubricant should be completely replaced. If possible, flush the oil line with fresh oil. When changing the lubricating oil, make sure that the new and old models of the replaced oil are the same and supplement the required oil level.
Use an oil bath type lubrication system. If the oil temperature is below 60 ° C (140 ° F) and the lubricant is not contaminated, replace the lubricant once a year. If the oil temperature is between 60-100 ° C (140-210 ° F), the lubricant needs to be replaced four times a year. If the oil temperature is between 100 and 120 ° C (210-250 ° F), the lubricant needs to be replaced once a month. If the oil temperature is above 120 ° C (250 ° F), the lubricant needs to be replaced once a week.
Proper installation and maintenance are important factors in the normal operation of SKF bearings. At the same time, care must be taken to maintain the cleanliness of the bearings. Bearings must be protected from contaminants and moisture and must be properly installed and lubricated. In addition, the design of the bearing arrangement, the condition of the oil seal, the form of the lubricant and the replacement cycle and the special maintenance also play an important role and must be paid attention to.

For more information and purchase please visit: https://www.supplyforever.com 

IKO import bearing failure judgment and replacement measures

1. Contact fatigue failure
Contact fatigue failure refers to the failure of the working surface of IKO imported bearings due to the alternating stress. Contact fatigue spalling occurs on the bearing working surface, often accompanied by fatigue cracking, first from the maximum alternating shear stress below the contact surface, and then extended to the surface to form different peeling shapes, such as pitting or pitting. Peeled into small pieces called shallow peeling. Due to the gradual enlargement of the exfoliation surface, it tends to expand deeper and form deep exfoliation. Deep exfoliation is a source of fatigue in contact fatigue failure.
2, wear and tear
Wear failure refers to the failure of the relative sliding friction between the surfaces resulting in the continuous wear of the metal on the working surface. Continued wear and tear will cause gradual damage to the bearing parts and eventually lead to loss of dimensional accuracy of IKO bearings and other related problems. Wear may affect the shape change. The increase of the clearance and the change of the surface of the working surface may affect the lubricant or cause the pollution to a certain extent, resulting in complete loss of the lubrication function, thus causing the bearing to lose the rotation precision or even the normal operation. Wear failure is one of the common failure modes of various types of bearings. It is usually classified into the most common abrasive wear and adhesive wear according to the form of wear.
1) Instrument detection
Using a spectrometer such as a spectrometer or SPM or a new VIB05 detector to determine the operating state of the bearing to determine whether maintenance or replacement should be performed is the most convenient and reliable method.
For example, when using the VIBO5 detector, this is a microprocessor-based machine state detection instrument with vibration detection, IKO imported bearing status analysis and infrared temperature measurement. The operation is simple, and the status alarm is automatically indicated. It is very suitable for the field equipment operation and maintenance personnel to detect the equipment status, find problems in time, and ensure the normal and reliable operation of the equipment.
With such an instrument, the bearing working potential can be fully utilized, the bearing warranty can be timely and the failure can be avoided, and it is suitable for young workers to make up for their lack of experience.
2) Manual detection
In places where the above instruments are not available, it can be detected using a monitoring instrument similar to that of a medical stethoscope. Experienced operators can also use the tools such as round bars or wrenches to resist the outer casing of the machine, and use the ear to monitor through the tool. The sound of the bearing.
The normal IKO imported bearing running sound should be uniform, stable and not harsh, and the abnormal bearing running sound is intermittent, impact or harsh sound.
This method is suitable for the operation of experienced staff, which mainly depends on the accumulation of staff experience.

For more information and purchase please visit: https://www.supplyforever.com

Technical introduction of high speed spindle bearings for machine tools

Technical introduction of high-speed spindle bearings for machine tools (machine tool bearings):

Increasing the speed of the spindle bearings is the key to achieving a high-speed, practical spindle. With the development of high speed, it is efficient for machining machine tools. The rolling element is made of ceramic material, the dmN value is about 20×104, and the numerical control machining center with dmN value of 100×104 under grease lubrication condition is increasing day by day. It has become a development trend, and the oil and oil mist lubrication method will become the future. The development direction of high-speed machine tool spindle bearing lubrication.

1 high-speed spindle bearing development:

Generally, angular contact ball bearings with excellent rigidity and high speed performance are used, in order to meet the high speed requirements of the machine tool spindle. Secondly, cylindrical roller bearings are used.

The dmN value under grease lubrication conditions is 50×104 or less. After the development of oil and gas lubrication, at the same time, gradually develop a compatible lubrication system. From the dmN value of the high-speed performance of the spindle bearing (dm is the diameter of the bearing pitch circle mm × N is the speed r / min. The dmN value has reached 100 × 104 or more. Later, in the bearing, the angle of the rolling element is ceramic Contact ball bearings, after the dmN value of 200 × 104 × 90 years developed spray lubrication, dmN value can reach 300 × 104.

2 high speed spindle bearing technology:

(1) High-speed angular contact ball bearings:

Single row and double row cylindrical roller bearings are inferior to angular contact ball bearings in terms of high speed performance. Angular contact bearings are bearings with contact angles, and tapered roller bearings can be seen. The larger the contact angle, the better the axial stiffness, but since the gyro sliding and the spin sliding between the ball and the raceway are also large, the heat is also increased. In order to improve the speed performance, the method is to reduce the size (or mass) of the ball to change the curvature coefficient of the channel, to reduce the centrifugal force of the ball, reduce the internal load generated during high-speed operation, and increase the number of balls to increase the rigidity.

For more information and purchase please visit: https://www.supplyforever.com

Teach you a few practical tips for fault diagnosis of rolling bearings

Rolling bearings are widely used in equipment. The condition of rolling bearings is directly related to the operating state of rotating equipment. Especially in large-scale continuous production enterprises, it is widely used in important parts of large-scale rotating equipment. Therefore, in actual production, the rolling bearing condition monitoring and Fault diagnosis is an important part of equipment maintenance and management. After long-term practice and exploration, we have accumulated some practical skills for the actual fault diagnosis of rolling bearings.

First, the method and key points of rolling bearing fault diagnosis

A practical method for condition monitoring and fault diagnosis of rolling bearings is vibration analysis.

In practice, you need to pay attention to the location and acquisition method of the measuring point. In order to accurately and accurately reflect the vibration state of the rolling bearing, it must be noted that the collected signal is accurate and true. Therefore, the measuring point should be arranged in the nearest place to the bearing. Generally, there is a rear fan cover at the free end of the motor, and the measuring point is selected in the fan cover fixing screw. Good monitoring results. In addition, it is necessary to pay attention to the multiple acquisition and analysis of the vibration signal, and comprehensively compare. To get an accurate conclusion.

Second, the characteristics of rolling bearings normal operation and practical diagnostic techniques

In the long-term production status monitoring, we found that the rolling bearing showed strong regularity during its use and the repeatability was very good. Normal high-quality bearings are relatively small in vibration and noise at the beginning of use, but the spectrum is somewhat scattered and the amplitude is small, which may be due to some defects in the manufacturing process, such as surface burrs.

After a period of motion, the vibration and noise are maintained at a certain level, and the spectrum is very single, only one or two times the frequency. There are very few spectrums above the power frequency, and the bearing status is very stable and enters a stable working period.

After continuing to run, the bearing vibration and noise begin to increase, and sometimes abnormal sounds occur, but the vibration increase changes slowly. At this time, the bearing kurtness value suddenly reaches a certain value. We believe that the bearing is an initial failure at this time.

At this time, it is required to closely monitor the bearing and pay close attention to its changes. After that, the bearing kurtosis value begins to drop rapidly and approaches the normal value, while the vibration and noise begin to increase significantly, and the increase rate begins to accelerate. When the vibration exceeds the vibration standard (such as ISO2372 standard), the bearing kurtosis value also begins. Rapid increase, when both the vibration standard is exceeded, and the kurtosis value also exceeds the normal value (the available kurtosis is relative to the standard), we believe that the bearing has entered the late fault production, and it is necessary to repair the equipment in time and replace the rolling bearing.

The bearing exhibits late fault characteristics to serious faults (generally bearing damage such as axle hung, burn, sand frame spalling, raceway, bead wear, etc.). The time is not more than one week. The larger the equipment capacity, the faster the speed. The shorter the interval. Therefore, in the actual rolling bearing fault diagnosis, once the late fault characteristics are found, the bearing should be judged decisively and the maintenance should be arranged as soon as possible.

For more information and purchase please visit: https://www.supplyforever.com

Common bearing wear failures and troubleshooting methods

        In general, if the bearing is used correctly, it can be used until the fatigue life is reached. However, there will be accidents that are prematurely damaged and cannot be used. This early damage, as opposed to fatigue life, is a quality use limit called a fault or accident. Many of them are caused by inadvertent installation, use, and lubrication, and foreign objects intruding from the outside are insufficiently studied for the thermal effects of the shaft and the outer casing.
Regarding the damage state of the bearing, such as the ferrule of the roller bearing and the jam of the rib, it may be considered as a cause of insufficient lubricant, unsuitability, defects in the oil supply structure, intrusion of foreign matter, bearing installation error, shaft deflection If the song is too big, there will be coincidences of these reasons.

Therefore, it is difficult to know the true cause of the damage by only investigating the bearing damage. However, if you know the mechanical use of the bearing, the conditions of use, the structure around the bearing, and the situation before and after the accident, combined with the damage state of the bearing and several reasons, it can prevent similar accidents from happening again.

For more information and purchase please visit: https://www.supplyforever.com

Several points of attention for maintaining and testing NTN bearings

1. In the process of using NTN bearings, regular cleaning is very important. How to clean the bearings accurately? When the bearing is first removed for inspection, first use the method of photography to make a good appearance record. Also, verify the amount of lubricant remaining and sample the lubricant before cleaning the bearings.
2. The cleaning of the bearing is divided into rough washing and fine washing, and the metal mesh frame can be placed on the bottom of the used container.
3. When rough washing, clean the grease or adhesive with a brush on the top of the oil. At this time, if the transfer bearing is moved in the oil, the rolling surface is damaged by foreign matter such as foreign matter.
4. When fine washing, slowly shifting the bearing in the oil, it must be forced to stop.
5. The cleaning agent used on weekdays is neutral non-aqueous diesel or petroleum, and sometimes uses warm alkaline liquid according to demand. Regardless of which cleaning agent is used, it is often necessary to filter and clean the cockroach.
6. Immediately after cleaning, apply anti-rust oil or anti-rust grease to the NTN bearing.
In order to make the imported bearings serve the mechanical operation for a longer period of time, it is necessary to perform regular inspections on the NTN bearings on a regular basis. Through the inspection, the problems caused by the mechanical operation can be effectively found, and the problems can be solved satisfactorily. Increased bearing life.
At the time of inspection, it is mainly correct to observe whether the rivet head of the bearing is skewed or loosely welded. The welding of the cage is good or bad. Whether the solder joint is too small, there is a problem that the solder is not strong, or the ball is caused by excessive soldering. They are all special places to pay attention to when testing imported bearings. There are still some issues to be aware of.
Local inspection of the bearing. First of all, the inspection of imported bearings in the environment should be carried out in a light environment, preferably astigmatism, in order to better observe the outside of the bearing and see that there are no cracks and other abnormalities on the surface. For example, wear, scratches and bumps in the mechanical cloud process can cause the bearing device to shift, resulting in poor position of the device, causing flat load and stress concentration, and the accuracy and service life of the molded bearing are reduced.
In addition, the working environment also pays special attention to moisture or contaminants, which are most likely to cause the bearing to rust. The rust is caused by poor installation of the NTN bearing, and early wear and tear, and the bearing will be directly scrapped. Therefore, pay special attention to waterproof and moisture during use.

For more information and purchase please visit: https://www.supplyforever.com

The effect of grease on the service life of KOYO bearings

    The use factors mainly refer to whether the installation adjustment, use and maintenance, maintenance and repair, etc. meet the technical requirements. According to the technical requirements of KOYO bearing installation, use, maintenance and maintenance, monitor and check the load, speed, working temperature, vibration, noise and lubrication conditions of the bearing in operation, find out the cause and immediately adjust the cause, make adjustment It returned to normal. The installation condition is one of the primary factors in the use factor. The bearing is often changed due to improper installation, and the force state between the parts of the whole bearing changes. The bearing is operating in an abnormal state and the end of the service life is early. Refers to the three major factors that determine the quality of the bearing, such as structural design, manufacturing process and material quality.
    The metallurgical quality of imported bearing materials was once the main factor affecting the early failure of rolling bearings. With the advancement of metallurgical technologies (such as vacuum degassing of bearing steels), the quality of raw materials has improved. The proportion of raw material quality factors in bearing failure analysis has dropped significantly, but it is still one of the main factors affecting bearing failure. The proper selection of materials is still a factor that must be considered in bearing failure analysis.
    Bearings are generally manufactured through multiple processes such as forging, heat treatment, turning, grinding and assembly. The rationality, advancement and stability of each processing technology will also affect the life of the bearing. The heat treatment and grinding processes that affect the quality of the finished bearing often have a more direct relationship with the failure of the bearing. In recent years, research on the metamorphic layer of bearing working surface shows that the grinding process is closely related to the bearing surface quality.
The main task of KOYO bearing service life analysis is to find out the main factors causing bearing failure based on a large amount of background materials, analysis data and failure modes, so as to propose improvement measures in a targeted manner, prolong the service life of bearings and avoid bearing protrusion. Early failure of the hair.
    In general, the grease filling amount in the KOYO bearing always exceeds the actual required amount of direct participation in lubrication, in the cavity of the holder and the bearing cover, and forms a contour on the periphery of the rolling element. During this process, the bearing temperature rises rapidly due to the resistance of the excess grease. Although most of the excess grease is squeezed out at the beginning of the run, the grease that is squeezed into the raceway attachment may still be carried by the rolling element into the raceway. In the early stages of bearing operation, most of the grease is squeezed out of the raceway very quickly (less than a minute), and the build-up grease is discharged a small amount while circulating along with the bearing rotor. At this time, the bearing temperature continues to rise until the excess bearing grease is completely discharged, which can be called the walking phase of the grease. According to the grease quality and filling amount in the bearing structure, this time may last for more than ten. Minutes, even hours.
After the remaining KOYO bearing grease is completely discharged, the remaining small amount of grease forms a thin layer of grease film on the mutual contact surface of the rolling element, the raceway and the cage, thereby entering the normal bearing. Operational phase. At this time, the temperature gradually drops and reaches equilibrium. In other words, long-term lubrication is mainly borne by this layer of grease film. In addition, during the long-term operation of the bearing, the contour of the rolling element and the raceway and the grease on the cage are shrunk to separate a part of the base oil, and after flowing into the raceway, the lubrication is also supplemented.

For more information and purchase please visit: https://www.supplyforever.com