High speed low noise slewing bearing bearings are shipped

/分类： /作者：

Recently, the high-end slewing bearing for medical CT machine designed and produced by our company for customers has been successfully rolled off the production line, and all the indicators of the finished product have passed the inspection.

For the CT machine special slewing bearing, we understand the various technical requirements of the customer, and calculate the bearing capacity and service life according to this requirement. After more than a month of full technical communication, Technical parameters, confirmed the production drawings. This product has an outer diameter of 1180mm and an inner diameter of 980mm. It has a toothless four-point contact ball slewing bearing structure with P5 accuracy. It is a high-end precision slewing bearing; and because it is medical, it has extremely high requirements for noise reduction.

According to the actual working conditions of customers, our technical engineers actively improve the product processing technology, and strive to make products that meet the actual needs of customers. First, the 42CrMo quenched and tempered material is used to make the material performance better and more stable, which guarantees the product quality from the source; secondly, the product raceway and appearance are comprehensively polished to ensure high product precision; thirdly, for the product’s silent requirements, A special segmented nylon cage device is used to lock the ball in the cage pocket while ensuring that the steel ball can rotate freely, thereby reducing the noise impact caused by the free movement of the cage in the raceway. Reduce rotating noise. Through the above efforts, we ensure that the finished products of the slewing ring meet various technical requirements.

 

After the finished product came out, after trial assembly test, it has fully met the requirements of the confirmed drawings of both the customer and us, and the rotation is flexible and light, and the rotation is silent. At present, this product is already on the way to customers.

 

The vision of “Let the world fall in love with Made in China” is not only a slogan, but also implemented in practical actions. It requires countless Chinese companies to constantly challenge themselves technologically and seize the right to speak for China in the core field of manufacturing. In the era of high-tech industry, only Chinese manufacturing can win the “tough battle” and truly realize “Let the world fall in love with Chinese manufacturing!” We Hengguan people carry this great dream and actively practice it! The road is long and long, Hengguan people will persevere in pursuit! May you and I walk along this great journey…

How long does the turntable bearing grease is filled?

/分类： /作者：

The turntable bearings are widely used in construction machinery and other equipment platforms. During the use of turntable bearings, the lubrication work is very important that there is no lubrication will greatly reduce the life of the bearing, to ensure that the bearing is effective, reliable, and the bearings must be sufficient. Lubrication, lubrication is the basic component of the bearing. Therefore, the filling of the grease has an important role in the normal use of the turntable bearing. So, how long does it know how long the turntable bearing grease is filled?
Be
First, the filler of turntable bearing grease
Be
1, fill grease
Be
Before running the bearing machine, it is necessary to make a supplemental finale. When filled with grease, the bearing should be rotated while the bearing is filled, and the grease is uniformly distributed until the sealing strip is observed at the sealing strip of the bearing. Overflow.

Tuto bearing

2, daily automatic fetipple
Be
After the incident, the automatic filling system can be opened, and the quantitative oil is injected daily (timing), which satisfies the normal use of the bearing, and the amount of the inclusions in the two months should at least reach the cavity volume value of the inside of the turntable bearing, in order to ensure the sufficient amount of oil Bearings, on the one hand, pay attention to the consumption of grease, on the other hand, to periodically detect oil passages to prevent leakage.
Be
At around three months, a concentrated finale should be carried out inside the turntable bearing, and the upper row-to-mouth hole should inject a large amount of grease to the upper sealing strip, and fresh grease spillage is uniform.
Be
Second, three row roller turntable bearing grease
Be
The bearing structure is protruding the rolling cavity ZUI, and the upper roller grease will move in the downward roller, and the upper row grease should be appropriate, the reference value is the middle row and the lower row 130% of the amount of oxime.

Tuto bearing

Third, what are the lubricates commonly used by turntable bearing
Be
Commonly used grease is calcium based grease, lithium-based grease, aluminum-based grease, and high temperature grease, and the user can select a suitable grease according to the particular situation.
Be
The above is about how long to fill a solution, and the timely filling grease is important, but the regular cleaning is also important, the turntable bearing is cleaned up, and the plane of the support driver is cleaned up, and the above oil, Burring and some debris removal, there is a clean working environment before installation. Further, the turntable bearing must be added to the new grease grease or a lithium-containing lithium-containing lithium-containing molybdenum containing molybdenum.

Talking about the cold treatment process of bearing steel

/分类： /作者：

The heat treatment operation of continuously cooling the quenched workpiece from normal temperature to a lower temperature to transform the retained austenite into martensite is called cold treatment. The purpose of cold treatment is to improve the hardness and wear resistance of steel, and stabilize the size of the workpiece. It is mainly used for bearings, tools and some carburized parts.

 

  1. Cold treatment process of bearing steel

 

The cold treatment of bearing steel often uses a freezer and dry ice alcohol solution. Precision bearings have higher requirements for dimensional stability; after the ring is quenched (especially staged quenching), the internal structure still retains more retained austenite. This retained austenite is an unstable structure. When storing and using the bearing In the process, changes will continue to change the accuracy of the bearing. For this reason, the cold treatment process is adopted, which can reduce the retained austenite in the structure and slightly increase the hardness of the parts.

 

After quenching and cooling the workpiece to room temperature, it is immediately placed in an environment below room temperature for a certain period of time, and then taken out and placed at room temperature. This treatment below room temperature is called cold treatment. The cold treatment of bearing steel often uses a freezer and dry ice alcohol solution. Stay at room temperature after quenching: After quenching, the material must be cooled uniformly inside and outside to room temperature and then cold treated, otherwise it will be easy to crack. Cold treatment immediately after cooling to room temperature (generally no more than 30min), otherwise it will stop the transformation of austenite to martensite change.

 

2, cold treatment temperature

 

The temperature of the cold treatment is mainly based on the martensitic transformation termination temperature Mf of the steel. In addition, the influence of the cold treatment on the mechanical properties and the manufacturability should also be considered. For GCr15 steel, the cold treatment is -70℃; when the precision requirements of ferrules or equipment are limited, the cold treatment temperature can be -40～-70℃; for ultra-precision bearings, it can be between -70℃～-80℃ Perform cold treatment in between. The temperature of the subcooling affects the impact fatigue and contact life of the bearing.

 

3, cold treatment heat preservation

 

Although the transformation of a large amount of martensite is completed when it is cooled to a certain temperature, in order to make the surface and core of a batch of ferrules reach the cold treatment temperature uniformly, a certain holding time is required, generally 1～1.5h.

 

 

  1. Tempering after cold treatment

 

The ferrule is placed in the air after cold treatment, and its temperature is slowly raised to room temperature and then tempered in time. The temperature rise should not be too fast, otherwise it is easy to crack; the tempering is timely, otherwise the larger residual stress inside the ferrule will cause the ferrule to crack, generally not more than 2h.

 

  1. cold treatment time

 

For the length of holding time of cold treatment, some scholars believe that the amount of retained austenite transformed into martensite depends only on the temperature reached by cooling, and the retention time at low temperature does not matter, because retained austenite-martensite transforms at low temperature The cooling is completed in an instant, so there is no need to keep it at a low temperature, just let the workpiece cool from the outside to the inside. It is also believed that the cold treatment time should be determined according to the thermal conductivity of the workpiece, the volume, the time required for cooling through, and the stability of the transformation of retained austenite. The retained austenite in the steel is fully transformed and is more conducive to the formation of carbide particles. After the transformation is completed, the hardness of the parts will not change significantly. Therefore, the holding time of cold treatment also needs to be reasonably controlled according to the actual situation.

 

In fact, there are many studies on cold treatment of bearing steel, including GCr15 steel, aviation high temperature bearing steel, carburized bearing steel, etc., except for the reduction in toughness (decreased impact toughness, 21% reduction), almost all of the research All show the many advantages of cold treatment: reduced Paralympics; increased hardness; increased wear resistance; increased tensile strength; fine carbide precipitation, increased fatigue life, etc.

What are the requirements for the packaging of bearings?

/分类： /作者：

For bearing products, packaging is very important, not only to prevent rust, but also to protect the bearing from bumps during transportation and damage to the bearing. Bearing packaging is divided into inner packaging and outer packaging. So, what are the requirements for the packaging of bearings?

First, the inner packaging of the bearing

After the bearing is manufactured and passed the inspection, it will be cleaned and anti-rust treated, and then put into the inner packaging to achieve the purpose of waterproof, moisture-proof, dust-proof, shock-proof, maintain the quality and accuracy of the bearing, and facilitate the use and sale. .

1. The inner packaging of the bearing is divided into three categories according to the anti-rust period

① Short anti-rust period packaging

The anti-rust period is 3-6 months, which is suitable for bearings that are shipped to the same subscriber in large quantities and put into use in a short period of time. The two parties have agreed to use simple packaging based on the principle of ease of use.

② General anti-rust period packaging

The anti-rust period is one year, suitable for general-purpose bearings.

③ Long anti-rust period packaging

The anti-rust period is two years, suitable for special and precision bearings.

2, bearing inner packaging material requirements

There are polyethylene plastic tube (box), kraft paper, plain and wrinkled polyethylene composite paper, paper box, polyethylene or polyethylene plastic film, nylon fastening tape or plastic woven fastening tape, waterproof high-strength plastic tape, burlap bag, etc. . All of the above materials need to ensure that the corrosion resistance test of the material is qualified.

3, the requirements of bearing inner packaging method

①Miniature bearing

Every 10~15 sets of bearings are packed into a plastic tube, and every 5~10 plastic tubes are packed into a carton (or bag or roll pack).

②Medium and small bearings

Multiple sets of bearings are wrapped with polyethylene film, kraft paper or polyethylene composite paper for external use; multiple sets of bearings are packed into a plastic tube (box); single set of bearings is packed in polyethylene film bags, folded or sealed before repacking Into a paper box.

③Large bearing

Pack it in a single set of polyethylene film or polyethylene composite paper, and then put it into a carton; use a polyethylene film bag, pack the single set of folded bag openings, and then put it into a carton; put the single set into a special plastic box; Three-layer wrap-around packaging: polyethylene film tape or composite paper tape for the inner layer, fastening tape for the middle layer, and waterproof permeable plastic tape for the outer layer.

④Extra large bearing

Single set of three-layer wrapping packaging (same as above).

Single-by-four-layer wrapping package: After the above-mentioned three-layer wrapping package, the outer layer is wrapped with a layer of linen tape.

For separable tapered roller bearings with outer diameter ≥150mm, the inner and outer components should be lined with polyethylene film before packaging, or the inner and outer components should be packaged separately. For interchangeable cylindrical roller bearings with an outer diameter of ≥150mm, because the complete package is easy to be damaged, the inner and outer components can generally be packaged separately.

Secone. Standards for bearing outer packaging requirements

1. General materials and requirements for outer packaging of bearings

① Double corrugated boxes, the total weight (gross weight) of each box does not exceed 25kg, and the outside of the box is bound with plastic strapping.

② Nail board box (wooden box), the total weight of each box does not exceed 30kg, and the outside of the box is bound with blue steel tape.

③ Calcium plastic corrugated box, the total weight of each box does not exceed 25kg, and the box is bound with plastic strapping.

When packing bearing products with inner packaging into the box, plastic bags or plastic films should be lined in the box first; if there are gaps in the box, it should be filled with corrugated paper blocks, paper scraps and other dry materials.

2, pay special attention

It is especially important to emphasize that due to the heavy weight of large bearings, packing straps should be added to the packaging box to ensure the convenience of bearing handling and other processes. For the packaging of large bearings, each manufacturer has its own characteristics, such as the material requirements for the outer packaging, anti-counterfeiting marks, and so on.

Compared to other products, the packaging and transportation of bearings are very important. Whether it is a bearing manufacturer or a motor manufacturer, we are inseparable from the transportation link without exception. We must fully communicate with the transportation party and take necessary precautions.

How to maintain the crane slewing ring?

/分类： /作者：

The slewing bearing is an important “joint” of the crane, so its maintenance is very important. So how to maintain the crane slewing ring?

When carrying out maintenance work, the first thing to pay attention to is the danger of being dragged into the rotating pinion, as well as the danger of crushing and shearing. When performing the following tasks, make sure that when starting the engine to perform the necessary slewing and luffing actions, any maintenance personnel are not in the danger zone between the main boom, the upper car and the reel, or between the exit and the reel. Dangerous areas, except for crane operators (in the driver’s cab).

1. Check the bolts of the slewing ring

1. Before each crane work or at least once a week, visually inspect the bolts on the slewing ring;

2. After the slewing ring has been working for 100 working hours, check whether the bolts are loose or not. Check again at the 300th working hour; check every 500 working hours thereafter; shorten the inspection interval for severe working conditions. If the bolts are found to be loose during the inspection, please stop the construction work and contact the local after-sales service department immediately. The factory or professional technicians will inspect and decide whether to disassemble and inspect immediately.

3. The slewing ring is filled with lithium grease before installation.

4. When replacing bolts, wipe the bolts clean, apply thread fastening glue and tighten them; use a crane in accordance with the requirements of the operation manual and lifting performance table, or check the fastening bolts regularly as required to avoid fatigue damage of the bolts. danger.

2. Routine inspection of slewing ring

1. Regularly check the flexibility of rotation; if noise or impact is found, stop the machine for inspection and troubleshoot immediately, and dismantle and inspect if necessary;

2. Regularly check whether the rotary gear ring is cracked or damaged, and whether the meshing tooth surface has biting, gnawing, peeling, etc.;

3. Regularly check the integrity of the seal. If the seal band is found to be damaged, it should be replaced in time, and if it is found to be off, it should be reset in time.

Three, lubricate the tooth surface of the slewing ring

The slewing ring gear has been coated with anti-rust oil before leaving the factory. The effective period of this anti-rust is generally 3 to 6 months. After the effective period, the anti-rust oil should be coated in time. In addition, during use, prevent the slewing bearing from being directly exposed to sunlight. It is forbidden to rinse the slewing bearing directly with water to prevent water from entering the raceway, and prevent hard foreign objects from approaching or entering the tooth meshing area.

Fourth, the raceway of the sliding slewing ring

The raceway must be filled with grease regularly according to the working environment. After working for 50 working hours, the raceway should be filled with lubricating grease, and then again every 300 working hours. The slewing bearing must be filled with grease before and after being placed for a long time.

If using a steam jet cleaner or a fixed water sprayer to clean the crane, care must be taken to ensure that water does not seep into the slewing ring connection, and then the slewing ring connection must be lubricated. In special working environments, such as tropical, high humidity, dust, large temperature changes, and continuous work, the lubrication cycle should be shortened.

Grease filling should be carried out when the slewing ring rotates slowly. When the lubricating grease overflows from the seal, the filling is completed. The overflowing grease will form a thin film to act as a seal.

Which bearings are used in wind turbines?

/分类： /作者：

Wind turbines are installed in areas with windy sand or relatively high humidity in the wild. The working conditions of wind turbine bearings are very harsh, and the temperature, humidity, and load that need to be subjected to a wide range of changes. In particular, the yaw and pitch bearings need to withstand large axial forces and overturning moments, and the gearbox bearings need to withstand huge shock loads during starting and braking. At the same time, the wind turbine gearbox bearings are required to have low friction when starting at low speeds. Features of torque and high operating flexibility. There are as many as 32 sets of bearings for a wind turbine. Therefore, the selection of bearings is very important to ensure the safe and stable operation of wind turbines. So, which bearings are used in wind turbines?

 

Wind turbine bearings are generally divided into the following types: yaw bearings, pitch bearings, main shaft bearings, gearbox bearings and generator bearings. According to different bearing types, technical requirements are also different.

 

1, yaw, pitch bearing

 

This type of bearing is generally designed as an assembly. Single-row four-point contact ball slewing bearings or double-row four-point contact ball slewing bearings should meet the following technical requirements:

 

According to the force characteristics of the wind turbine bearing, the yaw bearing adopts a small clearance, and the pitch bearing adopts a four-point contact ball bearing with zero clearance or “negative clearance” design. The channel needs to be specially designed and processed to withstand large The axial load and moment load. The yaw gear in the assembly should choose the appropriate material, modulus, tooth profile and hardness to ensure the life matching with the driving gear. At the same time, targeted heat treatment measures must be taken to improve the strength of the tooth surface, so that the bearing has good wear resistance and impact resistance.

 

Because the fan is exposed to the field, there are strict requirements on the sealing performance of the bearing, and the sealing form of the bearing must be optimized to ensure that the life of the bearing is the same as that of the fan. Fans are installed at an altitude of more than 50m or even hundreds of meters. The assembly and disassembly costs are expensive. Therefore, they must have very high reliability. Generally, the life span of 20 years is required. In addition, the bearing structure is complicated, so the design and manufacturing requirements are extremely high.

 

 

 

2, spindle bearing

 

Spindle bearings are generally spherical roller bearings, and some have double-row tapered roller bearings with large taper angles. Most of the impeller spindles are supported by two spherical roller bearings. Because the load of the main shaft of the impeller is very large, and the shaft is very long and easy to deform, the bearing must have good centering performance.

 

3, gearbox bearing

 

There are many types of gearbox bearings, including deep groove ball bearings, cylindrical roller bearings, full complement cylindrical roller bearings, double row tapered roller bearings, spherical roller bearings, thrust spherical roller bearings and four Point contact ball bearings.

 

The bearings in the gearbox are mainly lubricated by the gear oil in the gearbox. There are more metal particles in the lubricating oil, which will obviously affect the life of the bearing. Therefore, a special heat treatment process is required to make the surface of the raceway have compressive stress and reduce the raceway. Sensitivity to particle impurities improves bearing life. At the same time, it is also necessary to optimize the bearing structure according to the working conditions of the bearing, improve the processing technology of the bearing, and further improve the performance index of the bearing.

 

4, generator bearing

 

The generator bearing adopts cylindrical roller bearing and deep groove ball bearing. It is necessary to reduce the noise of bearing vibration through the structural design of these two kinds of bearings, the improvement of processing methods, the cleanliness control of the production process and the optimization of related components, so that the bearing has a good low-noise performance.

 

The above is the answer to which bearings are used in wind turbines. The bearings used from the main shaft to the generator are collectively referred to as transmission system bearings. Most of these bearings are standard bearings in terms of structure. The difference is that in order to ensure high reliability, In addition to some special requirements in terms of materials and heat treatment, other key technologies need to be adopted.

Methods and measures to improve bearing fatigue life

/分类： /作者：

Bearings are key machine parts that bear load and transmit motion. The challenges brought about by the increasing power density of modern equipment manufacturing industry have put forward higher requirements on the bearing capacity and reliability of bearings. Today, the editor will come to talk with you about methods and measures to improve bearing fatigue life.

Bearings in specific applications will fail prematurely, and their service life only accounts for 5%-10% of the calculated rated life. Many early failure bearings have a typical feature-a large-area subsurface crack network with “white etching morphology”, that is, white etching cracks.

There are many factors affecting white etching cracks, including raw materials, bearing design, lubrication, stress, surface and many other aspects. Among them, the bearing steel as a raw material, its composition design, purity, carbides, internal pores and other improper control will cause white corrosion cracks and cause early failure of the bearing. In order to obtain a high and stable fatigue life, the following aspects of the bearing steel production process must be done:

Slewing bearing

1. According to the application environment and characteristics of the bearing, select and design suitable bearing steel varieties, establish chemical composition internal control standards, and focus on the control of residual and harmful element content.

2. The oxygen content of the bearing steel, non-metallic inclusions and other purity indicators are improved through measures such as the control of the oxygen content of the steel in the primary furnace, the control of the amount of slag, the control of the slag composition, the control of the refining and pouring process, and so on.

3. According to different carbide quality requirements, choose different smelting processes such as vacuum degassing, electroslag, and self-consumption to obtain the corresponding level of carbide level. At the same time, we will do a good job in the process of temperature injection speed control, high temperature diffusion and other aspects of process optimization, to further improve the size and distribution of carbide particles, and reduce the risk of bearing fatigue life reduction caused by residual stress caused by microstructure changes.

4. For the rolling elements, the control of the microscopic pores in the bearing steel is even more important because there is no longer any thermal deformation treatment in the bearing manufacturing process. In the production process, it is necessary to focus on the control of processing methods, processing ratios, heating systems, etc.

5. Establish a complete bearing steel inspection system. On the one hand, it is necessary to formulate detailed laboratory sample preparation inspection plans, make full use of laboratory testing capabilities, objectively evaluate the physical quality level of each heat, and do a good job of high-frequency water immersion The promotion and application of new methods such as flaw detection and maximum extreme value detection; on the other hand, make full use of on-site surface and internal automatic flaw detection equipment to prevent the outflow of defective steel. Through the implementation of the above measures, the product quality level and quality stability are improved, thereby reducing the bearing white corrosion crack defects caused by raw materials.

Bearing manufacturing is a systematic engineering, and every link and step is very important. Therefore, in the design and production of bearing steel components, bearing manufacturing, heat treatment, processing and assembly, etc., qualified bearing products must be produced in strict accordance with the requirements of the standard.

Why the slewing bearing is not installed smoothly or even cannot rotate?

/分类： /作者：

Sometimes the technical indicators were normal when the rotation performance was tested in the factory, but the newly installed slewing bearing and slewing ring showed inflexible rotation. In addition, why the slewing bearing is not installed smoothly or even cannot rotate?

Reasons for the unsmooth installation of the slewing bearing

1, mounting hole. The threaded hole of the mounting hole is not standardized, the thread is not completely, and the thread is defective, which causes the bolt to be unable to be screwed in.

2. The center diameter and chord length of the mounting hole are out of tolerance too much, such as 3-5mm, causing the bolt to fail to perforate.

3, the positioning hole and the step size are out of tolerance and cannot be matched.

4. The bearing after heavy load has a dead center or ellipse in rotation, causing it to fail to operate normally.

5. The bearing is not in the installation direction of the installation design drawing, resulting in the opposite direction of the taper pin, which has potential safety hazards.

6. Interference of installation parts, such as tooth tip interference, there will be teeth gnawing phenomenon, and individual parts conflict with each other.

7. The negative clearance design is unreasonable, resulting in oblique force, unbalanced load and clearance after installation.

8. The equipment structure design is unreasonable, causing the debugging to not be carried out normally.

The slewing bearing may be difficult to rotate or unable to rotate

1. Idling of newly purchased products is not flexible

Please check the production date of the slewing bearing. If it takes a long time (such as more than half a year) and the climate is cold, it is possible that the salt mist and other temperament in the raceway will double the rotation resistance, which will make the slewing ring not work properly (cold areas, more prominent in winter) ) Elimination method: If it can run without other abnormalities, it can be used normally.

2, the operation after installation is not flexible

It may be that the surface of the main machine device and the surface of the slewing ring are not properly matched, resulting in that the axial clearance of the slewing ring behind the device cannot compensate for the deformation of the slewing ring. The slewing ring is in a state of negative clearance, and the rolling elements are difficult to run in the raceway (sometimes with abnormalities). Noise) or poor meshing of the large and small gears; or foreign matter stuck in the large and small gears. Elimination method: re-process the plane of the main machine device to make the device plane meet the requirements; re-adjust the gear meshing backlash according to the requirements, especially pay attention to the gear jump position; check to ensure that there is no foreign matter in the meshing position of the large and small gears; exchange a slewing bearing with a larger gap .

3, the operation is not flexible during use

The sealing strip is damaged, causing foreign matter to enter the raceway (such as poor working conditions, dust immersed in the raceway, etc.), and the isolation block is deformed and difficult to operate; there are hard objects or other conditions at the meshing of the large and small gears, such as broken teeth.

The above is an analysis of the annoying reasons why the slewing bearing is not installed smoothly or even cannot rotate. I hope everyone will be helpful after reading it. When testing the rotation performance of the new bearing, it can rotate lightly, but at this time, it does not represent a reasonable index. The contact point, contact angle, and relative position of the connecting point of the channel are in line, and whether the two circles are close to the perfect circle. The two circles are completely or close to positive balance. In layman’s terms, just like the two rails of a train, they should be close to theoretical parallel, high and low parallel, so that the train will be stable, high-speed, orderly and safe. Therefore, to test the rotation performance, the loading experiment is a very important basis and effective means.

Technical Difficulties of Fault Diagnosis for Ladle Turret slewing bearing

/分类： /作者：

The ladle turntable is one of the important key equipment of the continuous casting machine. Once these key equipment fails, it may cause the entire production line to stop production, disrupt the normal production rhythm, and seriously affect the normal production and economic benefits of the enterprise. In the structure of the ladle turret, the ladle slewing bearing is the key component of the stable and efficient work of the ladle turret. In order to ensure the normal operation of the supporting bearings, the factory will require on-site workers to conduct high-density inspections. However, due to the harsh on-site environment, on-site inspections are difficult, which not only increases the labor intensity of the workers, but may also threaten their lives.

The fault diagnosis of ladle turret slewing bearing has the following technical difficulties:

1. The speed of the equipment is low, and the impact energy caused by bearing damage is very low; and the equipment is greatly interfered by external forces, and the noise can easily cover the bearing fault characteristics; therefore, the conventional bearing detection methods cannot effectively find the bearing damage characteristics, such as time domain analysis, frequency Domain analysis, envelope demodulation spectrum, etc.
2. The bearing is subjected to complex forces, and it bears axial force, radial force and overturning moment at the same time;
3. During the operation of the equipment, personnel are not allowed to enter due to the harsh on-site environment; and a single offline monitoring cannot effectively evaluate the mechanical state of the equipment, and the amount of data is insufficient to support the judgment of the mechanical state of the equipment;
4. It is not only necessary to judge whether the equipment is faulty, but also to predict the residual life of the bearing, guide the direction of maintenance and repair, give play to the value of the equipment, and gain time for the preparation of spare parts and spare parts;
5. In order to ensure the accuracy of vibration analysis, diagnostic personnel need to have a very high level of professionalism and rich field experience. Even if the above conditions are met, the accuracy of diagnostic analysis cannot be guaranteed.

At this stage, there is no effective detection method for the bearing, and after the hidden trouble of failure, the fault signal characteristics are not obvious, it is difficult to find the bearing failure, and there is a high probability of causing secondary damage to the equipment, resulting in increased maintenance costs, and additional costs for the enterprise economic burden.

Therefore, the condition monitoring and fault diagnosis of the ladle turret slewing bearing not only guarantees the normal production needs of metallurgical enterprises in the continuous casting process, but also promotes the reform of the equipment management system, and will surely bring huge benefits. Condition monitoring and fault diagnosis are needed to reduce maintenance workload and maintenance time.

What is the impact of the amount of grease injected on the bearing?

/分类： /作者：

We all know that grease has good adhesion, wear resistance, temperature resistance, rust resistance and lubricity, can improve high temperature oxidation resistance, delay aging, can dissolve carbon deposits, and prevent metal wear debris and oil stains. Poly, to improve the wear resistance, pressure resistance and corrosion resistance of machinery, it will be commonly used in bearing products. For sealed bearings, appropriate grease has been filled during production; for open bearings, a sealing device is also installed in the host to prevent grease leakage. Today, the editor will talk to you about the impact of the amount of bearing grease on the bearing?

The amount of grease injected into the bearing will have a certain impact on its operation. If the amount of grease is too small, it is easy to cause lack of grease or dry friction, which will affect the life span. Too much grease will cause the bearing temperature to rise. A large amount of grease leakage not only pollutes the environment, but also causes waste. It can be seen that the amount of grease injected into the bearing should be as small as possible on the premise of ensuring sufficient lubrication of the bearing.

After understanding the movement process of grease in the bearing, it will naturally come to a conclusion: the grease in the bearing should not be too much. Too much grease is not only a waste, but also harmful. The higher the speed of the bearing, the greater the harm.

The more grease is filled, the greater the friction torque. With the same filling amount, the friction torque of the sealed bearing is greater than that of the open bearing. After the grease filling amount is equivalent to 60% of the internal space volume of the bearing, the friction torque no longer increases significantly. This is because most of the grease in the open bearing has been squeezed out, and the grease in the sealed bearing has also leaked out.

With the increase of the grease filling, the temperature rise of the bearing increases linearly. The temperature rise of the sealed bearing is higher than that of the open bearing at the same filling amount.

Slewing ring

It is generally believed that the grease filling amount of sealed rolling bearings should not exceed about 50% of the internal space. Tests have shown that 20% to 30% of ball bearings is appropriate.

Correct lubrication and regular maintenance can avoid bearing damage caused by lubrication problems. To ensure reasonable lubrication:

• Follow the instructions set by the device manufacturer for each device;

• When adding grease, it should be filled between the rolling parts of the bearing and the housing (or retainer) to ensure that sufficient grease enters and the surface of the key raceway is fully lubricated;

• Pay attention to when the bearing should be greased (Re-lubrication);

• Monitor the indicating instruments of the equipment, so as to find signs of problems as early as possible, such as temperature fluctuations and/or abnormal high temperatures;

• Pay attention to equipment noise or abnormal vibration;

• Observe lubricating oil leakage;

• Regularly sample the lubricating oil and check for contamination.

When injecting grease in addition, the site should be clean and clean, and the tools used should be cleaned with gasoline. After the grease is filled, other parts should be assembled as soon as possible to prevent the grease entering the bearing from entraining dust and sundries, especially sand and iron filings.