年归档： 2021

Mechanical work by the inevitable intrusion of dust and impurities, as a heavy machinery or equipment used in large bearings, each having its own rotary bearing mounting hole, and lubricating oil holes sealing means, but still be affected complex environment. Once raised properly, may cause mechanical member rotatable with the debris into the interior of the rotary support, the increased friction between the rotary support and related accessories, forming the movable catching phenomenon may even lead to a mechanical stop. So you need to master the operation management method of cleaning, clean the impurities to protect production machinery is running.

Deposition can not be cleaned in a rotary bearing raceways dust, resulting in clogging of the oil injection duct, stuck in the roller track. Adding auxiliary equipment using the temporary high pressure descaling fluid injection into the rotary bearing, by repeating the rotation, so that relative movement between the sub-friction rotary bearing, the grease deposited on the inner race, the dust clean. After the injection of oil into the clean slewing, the descaling fluid clean.

Regular check-related accessories slewing ring is necessary, impurities intrusion protection accessories or damage caused by improper use of lubricants will have a large slewing ring consumption and shorten life.

Slewing range of applications is very wide, we look at what it can be used in place of it below!

1, lifting machinery

Lifting has included cranes, tower cranes and trailers, etc., because these machines use environment is more severe, rotating parts are often severely affected, so these sites will be used to customize the slewing ring, such as to Xuzhou Wanda slewing bearing manufacturers to provide jobs and environmental dimensions required for the machine, slewing bearing manufacturers combined with the actual situation will arrange for engineers to design in line with the bearing, and then put to use, not only to meet the needs of lifting machinery, but also make use of life is greatly enhanced.

2, construction machinery

Simple mechanical engineering division is like excavators, loaders. Slewing bearing capable of withstand the axial and radial forces and overturning forces and very compact, an excavator in the job and requires continuous core member is rotated, the rotary bearing is rotated. Application of the construction machinery applications belongs to the basic slewing ring, is more widely used.

3, processing machinery

Processing machinery like material processing, food processing, metallurgy, etc.,. With the continuous development of technology, people are not satisfied only the slewing ring used in engineering machinery, instead looking to the device platform processing machinery. Because the slewing bearing more compact than the original, may be subjected to an external force greater, more performance and good structure, so that the processing machine also has multiple applications.

4, military equipment

Competition is now military hard power of military equipment, as we see on television as the tanks turned the gun head, a shell hit the target accurately, this session is slewing ring plays a good supporting role; as well as artillery, radar, rocket launchers, etc., timely and stable rotation jump in launching military equipment is very important structural slewing ring, compared to conventional bearings have a good performance.

5. Other

In addition to connecting portions revolving bearing in industrial and medical applications, etc. In addition, in the field of power generation and the life has its shadow, the wind turbine tower and the yaw bearing is mounted in the cockpit, the pitch bearing mounted on the root of each blade and the hub connecting portion. Each wind turbine pitch bearing and a yaw bearing three. By application of slewing on the wind power plant, may be implemented in different process implemented to change the wind power generation, in the process, the root of the blade portion associated therewith is embodied swivel support bearing. Aspects of life slewing ring main applications focused on the playground, like a Ferris wheel, roller coaster, carousel and large pendulum clock, etc., the application of the slewing ring life safety has been well protected.

The above is how to organize small series of slewing ring contaminated debris clean-up as well as the entire contents of its scope of application, hoping to be helpful to everyone. Constant crown bearing, customer demand-oriented, be flexible customization to meet the real needs of customers and innovative sophisticated. Constant crown bearing, made Moses future, only high-quality slewing ring bearings and work!

The pushing machine is to utilize vibration, static or hammering action to pull the pile of the formation of the formation of the formation of the formation. The pilot operation is often used to vibrate pile driver, static pressure pile machine or double-active hammer, and then equipped with pile frame and rigging, so it is also known as vibration sinking pile machine and static press pile machine. The use of swinging on the pile driver is or is the power element of the upper body and the underwriting body to perform the relative swivel movement, then how specifically uses it? Let’s introduce you to you.

1. Selection of pile drum rotation support
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The pile drum rotation supports the rotation of the device through friction and lubrication, and can drive the mechanical rotation in the pile drum, provide support capabilities, mainly rotating, supported, to withstand axial, radial, tip, and impact Loads, since the quality requirements of the rotary support are relatively high, and the two-volleyball-type rotary support is generally selected when selecting the rotary support type, which is fastened to withstand a large axial force and torrent torque.
Pumped pile driver
2, method of use of pile driver rotary support
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Pumped pile drivers are rotated similar to the use of pile drivers and excavators, and the rotary support is a force element that is on the vehicle body and the underwriter to support the vehicle body and to withstand the working load. The inner seat is connected to the vehicle body, the outer race is connected to the vehicle body, and the inner ring on the inner seat is engaged with the rotary motor pinion. When the rotary motor is rotated, the carriage is driven by the pinion. The rotary support of the pile driver uses an internal teeth rotation, because there is a hit load, and the general tooth surface is hardened.
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When the pile driver is more common in the construction, the pile of the pile is fixed to the pile head, and the pile driver is suspended in the hook by the spring absorbers and rigging. Causes pile and soil resonance, soil structure damage, the friction between the pile body and the soil is reduced, and the pendulum is tightened, and the pile is gradually pulled out. If the eccentric block vibrator is used, the eccentric block must be adjusted due to the difference in the resistance between the sink and the pile. Such pulling pile equipment is simple, high-pull pile efficiency, and development prospects.
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Hydraulic pile driver uses its clipper to clamping the pile head, the hydraulic cylinder forces the top pressure clipper, so that the top is rising from a distance, pull the piles, and apply the pile to the clay, sand or the soil Copstanding paper or steel piles in the layer. There is also a mechanical method to pull the pile, that is, driven the hoist by the motor, and pulls the pile to force the floor using the tension of the wire rope pulley. It is convenient to use, low cost, but the pile strength is not large, the equipment is cumbersome, and the push pile is low, only for soft land layer construction. Using the double-acting steam hammer, the hammer is inverted, fixed to the pile head, and hang it under the rigging, first shake the soil, reduce the tightness of the pile and soil, then start the steam hammer, hammer up Vibration, tightening the rigging, gradually pulling the piles, can be pulled with concrete piles and other piles in various soil layers.
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In general, the pushing machine is a large mechanical equipment, like the excavator crane, which produces a large working load and friction during the rotation, and the ordinary bearings cannot meet the needs of large-scale mechanical equipment, so it needs to be used. Go to the rotary support, and to customize according to the actual situation when selecting the model, a special process can be performed on some wear, and the quality of the rotary support is increased.

Recently, the high-end slewing bearing for medical CT machine designed and produced by our company for Middle East 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 bearing, we and the Iranian CT machine manufacturer, after more than a month of full technical communication, understand the various technical requirements of the customer, and calculate the bearing capacity and service life according to this requirement. 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.
High-speed silent slewing bearing 　　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. I believe that made in China will amaze foreign customers and win glory for the country! Hengguan Bearings actively responds to the call of President Xi and develops manufacturing in China towards high, precise and cutting-edge development!

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…

Nowadays, industrial technology is developing more and more rapidly, and various stainless steel materials are also being used in large quantities at this time. Industrial production cannot do without mechanical equipment, so many mechanical equipment cannot do without stainless steel bearings. Good stainless steel slewing ring bearings can be said to be an important guarantee for the production of mechanical equipment. Many friends are not particularly familiar with stainless steel slewing bearings. Next, the editor will talk about the characteristics of stainless steel slewing bearings for everyone to learn and understand.

1. The material of stainless steel slewing ring is special

Generally speaking, slewing bearings generally use two materials, 50Mn and 42CrMo, but stainless steel should be used for special purposes. The ferrules and rolling elements of stainless steel slewing bearings often use 9Cr18Mo, 9Cr18, 4Cr18 materials.

2. Excellent corrosion resistance

The sales volume of stainless steel bearings on the market is still considerable. You must know that stainless steel bearings have many advantages, so their durability is also very strong. First of all, good corrosion resistance is a major advantage of stainless steel bearings. Since this type of bearing has passed the extreme tests of high temperature and low temperature, it will have stronger corrosion resistance.

3. Washing resistance

Stainless steel bearings are also very resistant to washing. After we have used the bearings for a period of time, there is no problem in removing them for washing. Due to the water resistance of stainless steel bearings, rust will not appear even if they are washed in water.

4. Long service life

Because the material corresponding to the stainless steel bearing is the international standard stainless steel material, regular maintenance during daily use can extend its service life.

5. Wide range of use

Compared with slewing bearings of common materials, stainless steel slewing bearings have stronger rust and corrosion resistance, and are generally used in some special working conditions, such as underwater, wet seaside and other working conditions. Stainless steel slewing bearings are commonly used in food machinery, environmental protection equipment, medical equipment, and underwater operation tools.

The above is an introduction to the characteristics of stainless steel slewing bearings. Choose the appropriate dust cover and lubricant. Stainless steel slewing bearings can be used in an environment of -60℃~+300℃. Because of its high mechanical strength, large load capacity, and beautiful appearance, stainless steel slewing bearings are widely used in food processing, medical equipment, pharmaceutical machinery, nuclear industry projects and other equipment.

Luoyang Hengguan Bearing Technology Co., Ltd. mainly produces slewing bearings in the diameter range of 50-10000mm. Among them, stainless steel slewing bearings are a major characteristic product of Hengguan Bearings. At present, they have been equipped with stainless steel slewing bearings for many projects at home and abroad, and they are all very successful. Cases, well received and praised by customers.

With the increase of the operating time of the wind turbine, the sealing ring of the pitch bearing is gradually aging, the lubricating grease is gradually deteriorating, the waste grease is not drained smoothly and the pitch bearing is not completely rotated, resulting in uneven internal pressure, which will lead to the pitch bearing sealing ring. There are different degrees of grease leakage. If it is not handled in time, it may cause poor lubrication of the pitch bearing, thereby affecting the service life of the pitch bearing and the wind turbine. Today, the editor will conduct a detailed analysis of the causes of grease leakage in the pitch bearing of wind turbines for everyone to learn and understand.

 

The internal structure design of the pitch bearing is unreasonable

 

1, channel structure

 

The design of the pitch bearing channel affects the fluidity of the grease in the groove inside the bearing. Under normal circumstances, the variable pitch bearing is filled with grease from the grease hole. The pressure difference required to discharge the waste grease from the grease hole is less than the pressure value that the seal ring can withstand, and at the same time is greater than the resistance value of the grease flow, the seal ring No fat leakage. The required pressure difference is closely related to the resistance of the grease to flow. A small resistance requires a small pressure difference, and a large resistance requires a large pressure difference. If the design of the internal channel of the pitch bearing is unreasonable, the grease flow resistance will be large, which is not conducive to the uniform distribution of the grease and the internal pressure, and the grease cannot enter the grease discharge hole smoothly, resulting in poor grease discharge, resulting in grease at the seal ring overflow.

 

2, size and distribution of lipid pores

 

The grease injection holes and grease discharge holes of the variable pitch bearing should be distributed at reasonable intervals to ensure that the bearing can be smoothly injected with new grease and discharged. The distance between the adjacent grease injection hole and the grease discharge hole should be moderate. If the distance is too short, the pressure of the grease injection hole will be higher and the pressure of the grease discharge hole will be lower during grease filling, and the newly added grease will be easily discharged from the grease discharge hole; If the length is too long, the seal ring will bear greater local pressure when adding grease, which will easily lead to grease leakage. In addition, the cross-sectional diameter of the grease discharge hole is too small, the diameter of the grease collection bottle connected to the grease discharge hole is too small, and the distance between two adjacent rows of grease holes on the bearing is too large, which will also increase the resistance of grease discharge, resulting in poor grease discharge. Smooth, so that the internal pressure of the pitch bearing is too large, resulting in grease leakage.

 

Poor sealing

 

1. Aging and wear of the sealing ring

 

Most of the pitch bearings use nitrile rubber seals, which will age after long-term use. The aging rate is related to the acrylonitrile content in the nitrile rubber, the rubber content of the formula, the antioxidant and the use environment. In general, the nitrile rubber The service life of the sealing ring is 5~10 years. The pitch bearing adopts a contact seal. During operation, the seal ring contacts the friction surface of the seal. As the running time increases, the seal ring will gradually wear out, resulting in a decrease in sealing performance and insufficient pressure on the seal ring. Grease may be removed from the seal ring. Leakage.

 

2, the seal ring structure design is unreasonable

 

Pitch bearings generally use double-lip seals. The outer lip can block moisture, dust and other harmful substances from entering the inside of the bearing, and the inner lip can prevent grease leakage. If the seal ring structure design is unreasonable, the sealing effect will be affected after installation, and the seal ring may be deformed after the pitch bearing is operated, resulting in insufficient sealing ability or sealing failure, and the grease is easy to leak.

 

3. Improper installation and maintenance of the seal ring

 

Failure to install or maintain according to the process will result in uneven force on the seal ring. Poor interface bonding during the installation of the seal ring will cause the seal ring interface to break. After the subsequent pitch bearing grease injection operation, the seal ring is prone to bulging and warping (Figure 1 ) And the phenomenon of fracture, so that the grease will overflow from the gap, warpage and damage of the sealing ring.

 

4, the sealing ring is squeezed and damaged

 

When installing or maintaining the blades of wind turbines, hydraulic tensioners need to be used to apply torque to the connecting bolts between the blades and the pitch bearing. The distance between the connecting bolts and the sealing ring is relatively short, and the extension head of the hydraulic tensioner has a larger overall size. The stretching head is easy to press on the sealing ring to cause serious damage to the sealing ring, as shown in Figure 2. The subsequent operation of the pitch bearing may cause deformation and tearing of the sealing ring, resulting in a large amount of grease leakage.

 

Improper selection of grease or unreasonable setting of lubrication system

 

1. Improper selection of grease

 

The choice of grease usually refers to the actual working conditions of the pitch bearing, and also needs to consider the consistency of the grease and the type of additives. The consistency of the grease is closely related to the ambient temperature. Every time the ambient temperature drops by 5 ℃, the consistency will double and the fluidity of the grease will deteriorate. If the consistency of the grease is not appropriate or the pressure resistance is insufficient, subsequent use is likely to occur The solidification phenomenon blocks the grease system, causing the grease to not be discharged normally and leak from the sealing ring, as shown in Figure 3.

 

2. The amount of grease injection and the setting of the centralized lubrication system are

unreasonable

 

The pitch bearing needs to be filled with a certain amount of grease before operation. The filling amount is about 60% to 80% of the inner space of the pitch bearing. Generally, the filling amount is about 70%. There are also individual pitch bearing suppliers to ensure sufficient Choose 80% filling amount for lubrication.

 

Most wind turbines at home and abroad use centralized lubrication systems to fill the pitch bearing with grease. Some wind turbine manufacturers use manual and regular grease filling to further reduce the maintenance cost of the pitch bearing. Both of these two methods of refilling grease have shortcomings: the grease injection amount and grease injection period for manual regular grease injection are often empirical data, and there is a large deviation from the actual grease required for the pitch bearing. The grease injection volume is usually In this case, the lubrication time of the pitch bearing cannot be guaranteed. In addition, about 80% of the grease may be added to the pitch bearing before leaving the factory, which will easily cause a large amount of local grease to accumulate in the pitch bearing channel. ; The centralized lubrication system adopts automatic grease injection method to make the bearing lubrication more adequate. Although the lubrication time and grease injection uniformity of the variable pitch bearing are guaranteed, the centralized lubrication is performed when the variable pitch bearing is not running or the unit is shut down for a long time The system continues to inject grease according to its preset fixed program, which is also likely to cause a large amount of local grease accumulation in the pitch bearing channel.

 

Under normal conditions, the sealing pressure of the sealing ring of the pitch bearing is about 2.8×105 Pa. The grease injection pressure required when the pitch bearing is stationary and not working is about (2.5~2.8) x105 Pa. The grease injection pressure required when the pitch bearing is running is only It is about 0.6 x105 Pa. Due to the poor fluidity of the grease used in the pitch bearing, the large accumulation of grease caused by the above two kinds of grease injection methods will increase the pressure of the grease channel in the pitch bearing channel, thereby increasing the injection required during grease injection. Fat pressure. When the grease injection pressure is greater than the sealing pressure of the pitch bearing seal ring, the grease will leak from the pitch bearing seal ring under the action of the grease injection thrust.

 

In addition, if the air in the pressure pump or grease pipe of the centralized lubrication system is not completely emptied, the air will enter the pitch bearing channel along with the grease, resulting in excessive local pressure in the channel. When the pressure is greater than the pitch bearing The sealing pressure of the sealing ring will open the sealing ring, causing serious grease leakage.

 

3. Improper collection of waste fat

 

At present, the waste grease collection of pitch bearing of wind turbines generally adopts the method of installing grease collecting bottles in several waste grease discharge holes distributed on the circumference of the bearing. When new grease is added, the new grease squeezes the waste grease into the waste from the inner cavity of the bearing. Grease drains out of the small holes and drains into the fat collecting bottle, which needs to be cleaned regularly. In fact, as the running time of the pitch bearing increases, the waste grease collection effect is not good, and it is easy to leak grease.

 

The above is about the analysis and introduction of the reasons for the grease leakage of the pitch bearing of the wind turbine. As an important component of the wind turbine, the pitch bearing is used in a harsh environment, high maintenance costs, and complex forces, and directly affects the continuity of the entire pitch movement. Stability and accuracy. Therefore, in order to ensure the reliability of the life of the pitch bearing, the pitch bearing needs to be well sealed and lubricated to avoid grease leakage.