According to the bearing surface grinding metamorphic layer formation mechanism, the impact grinding metamorphic layer of the main factors is the grinding heat and grinding force. The following analysis on the reasons for bearing failure.
1 bearing the grinding heat
The thin bearings grinding, the grinding wheel and the workpiece contact area, consume large amounts of energy, resulting in a large number of grinding heat, causing the local instantaneous grinding zone temperature. Use of linear motion heat transfer theory derivation, calculation or application infrared and thermocouple method measured the instantaneous temperature under experimental conditions can be found in the 0.1 ~ 0.001ms instantaneous temperature within the grinding zone up to 1000 ~ 1500 ℃. Such instantaneous temperature, a certain depth sufficient to work the surface layer of high temperature oxidation, amorphous structure, high-temperature tempering, secondary hardening, cracking and other changes or burns.
(1) the surface oxide layer
The instantaneous high temperature steel surface under the role of oxygen in the air, up into very thin (20 ~ 30nm) thin layer of iron oxide. It should be noted that the oxide layer thickness and the total thickness of the surface layer of grinding deterioration test results showed a corresponding relationship. This shows that the thickness of the oxide layer which is directly related with the grinding process, the grinding quality is an important symbol.
(2) amorphous tissue layer
Instantaneous grinding zone so that the surface temperature reaches a molten state, the molten metal molecular flow has been evenly coated on the work surface, and is the base metal at breakneck speed cooling, forming a thin layer of amorphous tissue layer. It has high hardness and toughness, but it is only about 10nm, it is easy to be removed precision grinding.
(3) high-temperature tempering layer
Instantaneous grinding zone temperature to a certain depth can (10 ~ 100nm) is heated to a temperature above the tempering heating the workpiece. Does not reach the austenitizing temperature in the case, as the heating temperature is increased, the surface layer by layer will be generated corresponding to the temperature of the heating or tempering retempered organizational changes, hardness is decreased. The higher the heating temperature, the hardness decreased also more powerful.
2013年8月27日星期二
Installation of high-speed bearings fit and adjustment
A high speed bearings with clearance and according to both the high-speed precision bearings bearing requirements, but also according to temperature bearing requirements, so consider the coordination and clearance to take account of the following points:
(1) when the temperature rose to high temperature dimensional change and hardness; (2) caused by high speed centrifugal force system change and shape change.
In short, high-speed, high-temperature conditions, coordination and clearance from the choice of the bearing should strive to maintain the accuracy and performance, it is difficult.
In order to ensure the bearing raceway after installation of small deformation, interference fit amount of interference can not get too big, and high speed centrifugal force and high temperature thermal expansion, or offset with the surface normal pressure. Or so with the surface relaxation, so the amount of interference must be considered under the premise of these two factors be carefully calculated, at room temperature constant speed and effective amount of interference for high-speed bearings may be invalid.
If the calculation results of this contradiction is too large (usually only in the ultra high speed only in this case), only by taking the lubrication ring lubrication and hydrostatic lubrication with a double measure, and this solution has the potential to break the bearing dmn value 3 million mark.
In considering the high speed bearing clearance is not only to consider the above factors, but also to consider the thermal elongation axis of the impact on the clearance required bearing in working condition, that there is at operating temperature optimum clearance, which kind of clearance is taken into account, the outer ring ball groove center precise alignment of state formation. As high-speed bearings for lower relative sliding and internal friction, it is best not to use the inner and outer rings relative axial displacement method to adjust the ball bearing clearance.
In considering the amount of interference with the bearing and clearance, to note that materials at high temperatures becomes soft and easily deformed features, as well as many from the room temperature to high temperature changes cause some permanent deformation possibilities.
(2) the requirement for host-related parts
Where the rotational speed bearing system requires precision bearing dynamic balancing shaft and the bearing seat hole installation site should have higher than normal required size and shape precision accuracy, especially for concentricity and retaining shoulder seat hole or journal vertical, and in consideration of these issues, it must also be noted that the high-speed operation of the bearing element and the temperature factor.
Shaft support systems require both high rigidity, and quality requirements as light as possible, in order to overcome this contradiction can be taken, such as reducing the surface roughness and improve surface hardening measures to improve the supporting stiffness, the use of hollow shaft to reduce system quality.
3 high-speed bearings examples of the development hereby HA type with ultra high-speed development of tapered roller bearings for example.
(1) of the problem
In the gas turbine and certain machine tools and construction machinery, high speed and axial load, using the ball bearing is life is too short, use a short cylindrical roller bearing axial load capacity is insufficient, the axial clearance is difficult to adjust, hoping to use cone roller bearings break this problem.
(2) must be solved key technology
Increase speed limit tapered roller bearing technology lies in improving inner ring large rib and roller end lubrication between the state, this area most likely to occur at high speeds severe wear and burns, is the main reason for limiting its high speed.
(3) solution
The general structure of tapered roller bearings, the oil circulation routes in the inner wall with a large roller end contact area is difficult to get oil, and this part of the relative sliding big, precisely needed most lubricants.
Therefore, Japan and other countries have developed HA-type tapered roller bearings, this bearing wall in the outer ring, so that the flow of oil can lubricate the outer ring ribs and roller end contact part, but here even when at rest can also save some oil, to avoid the starting lean burn accidents, but click on the outer wall of the need to create several drain hole to prevent oil discharge passage without, retention caused by certain parts of the oil agitation loss of power and temperature l too high. Since no inner wall, the temperature decreased, thus reducing the mating surface between the inner ring and the shaft occurs between peristaltic possibilities. This structure of the bearing outer ring on the cage used to guide the way, so that the cage can be more smoothly guide roller without askew functioning to avoid vibrations and excessive wear and tear, which will also help speed.
(4) can be achieved
This bearing type HA dmn value up to 200 million, more than triple the normal structure, for example a gas turbine this bearing spindle gear (Model I-IA30205), the axial load 1000N conditions, guarantee There 2L/min the implementation of the bearing to the oil supply of the 4th cycle turbine oil, its working speed of up to 60,000 will not appear in turn burns.
(1) when the temperature rose to high temperature dimensional change and hardness; (2) caused by high speed centrifugal force system change and shape change.
In short, high-speed, high-temperature conditions, coordination and clearance from the choice of the bearing should strive to maintain the accuracy and performance, it is difficult.
In order to ensure the bearing raceway after installation of small deformation, interference fit amount of interference can not get too big, and high speed centrifugal force and high temperature thermal expansion, or offset with the surface normal pressure. Or so with the surface relaxation, so the amount of interference must be considered under the premise of these two factors be carefully calculated, at room temperature constant speed and effective amount of interference for high-speed bearings may be invalid.
If the calculation results of this contradiction is too large (usually only in the ultra high speed only in this case), only by taking the lubrication ring lubrication and hydrostatic lubrication with a double measure, and this solution has the potential to break the bearing dmn value 3 million mark.
In considering the high speed bearing clearance is not only to consider the above factors, but also to consider the thermal elongation axis of the impact on the clearance required bearing in working condition, that there is at operating temperature optimum clearance, which kind of clearance is taken into account, the outer ring ball groove center precise alignment of state formation. As high-speed bearings for lower relative sliding and internal friction, it is best not to use the inner and outer rings relative axial displacement method to adjust the ball bearing clearance.
In considering the amount of interference with the bearing and clearance, to note that materials at high temperatures becomes soft and easily deformed features, as well as many from the room temperature to high temperature changes cause some permanent deformation possibilities.
(2) the requirement for host-related parts
Where the rotational speed bearing system requires precision bearing dynamic balancing shaft and the bearing seat hole installation site should have higher than normal required size and shape precision accuracy, especially for concentricity and retaining shoulder seat hole or journal vertical, and in consideration of these issues, it must also be noted that the high-speed operation of the bearing element and the temperature factor.
Shaft support systems require both high rigidity, and quality requirements as light as possible, in order to overcome this contradiction can be taken, such as reducing the surface roughness and improve surface hardening measures to improve the supporting stiffness, the use of hollow shaft to reduce system quality.
3 high-speed bearings examples of the development hereby HA type with ultra high-speed development of tapered roller bearings for example.
(1) of the problem
In the gas turbine and certain machine tools and construction machinery, high speed and axial load, using the ball bearing is life is too short, use a short cylindrical roller bearing axial load capacity is insufficient, the axial clearance is difficult to adjust, hoping to use cone roller bearings break this problem.
(2) must be solved key technology
Increase speed limit tapered roller bearing technology lies in improving inner ring large rib and roller end lubrication between the state, this area most likely to occur at high speeds severe wear and burns, is the main reason for limiting its high speed.
(3) solution
The general structure of tapered roller bearings, the oil circulation routes in the inner wall with a large roller end contact area is difficult to get oil, and this part of the relative sliding big, precisely needed most lubricants.
Therefore, Japan and other countries have developed HA-type tapered roller bearings, this bearing wall in the outer ring, so that the flow of oil can lubricate the outer ring ribs and roller end contact part, but here even when at rest can also save some oil, to avoid the starting lean burn accidents, but click on the outer wall of the need to create several drain hole to prevent oil discharge passage without, retention caused by certain parts of the oil agitation loss of power and temperature l too high. Since no inner wall, the temperature decreased, thus reducing the mating surface between the inner ring and the shaft occurs between peristaltic possibilities. This structure of the bearing outer ring on the cage used to guide the way, so that the cage can be more smoothly guide roller without askew functioning to avoid vibrations and excessive wear and tear, which will also help speed.
(4) can be achieved
This bearing type HA dmn value up to 200 million, more than triple the normal structure, for example a gas turbine this bearing spindle gear (Model I-IA30205), the axial load 1000N conditions, guarantee There 2L/min the implementation of the bearing to the oil supply of the 4th cycle turbine oil, its working speed of up to 60,000 will not appear in turn burns.
2013年8月24日星期六
Bearing rings of cold treatment method
Quenching the bearing ring to cool to room temperature, immediately placed in an environment below room temperature a certain time, out at room temperature, this is lower than the processing temperature is called cold treatment. Bearing steel cold treatment is often used freezers and dry ice alcohol solution.
1 The role of cold treatment
Precision bearings for higher dimensional stability; ferrule hardened (especially quenching), the internal organization retains more residual austenite, this residual austenite is unstable organization, storage and use of bearings process will continue to change, thus changing the accuracy of the cross bearing. Therefore the use of cold treatment process, it can reduce tissue retained austenite, slightly increase the hardness of parts.
2 Cold Process
Stay at room temperature after quenching: quenching, must make uniform cooling to room temperature inside and outside the ring after the cold treatment, or easy to crack, cooled to room temperature immediately after cold treatment (usually no more than 30min), otherwise it will abort the austenite to martensite changes.
Cold treatment temperature: the temperature of cold treatment based primarily on termination of martensitic transformation temperature of the steel Mf, while also considering the cold treatment on the mechanical properties and process and other factors.
For GCr15 steel, cold treatment selection -70 ℃; accuracy is not very high ferrule or equipment limitations, the cold treatment temperature optionally -40 ~ -70 ℃; super precision bearings in the -70 ℃ ~ -80 ℃ between the cold treatment. Cold temperatures affect the bearing life impact fatigue and exposure.
Cold insulation: Although a large number of martensite is cooled to a certain temperature Tilting moment to complete, but the number of rings to make both surface and core part cold treatment to achieve uniform temperature, requires a certain holding time, usually 1 to 1.5 h.
Cold treatment after tempering: ferrule on the air after the cold treatment, the temperature was slowly warmed to room temperature tempering timely manner. Temperature can not be too fast, or easy to crack; tempering timely, otherwise the internal ferrule large residual stresses can cause cracking rings, generally no more than 2h.
1 The role of cold treatment
Precision bearings for higher dimensional stability; ferrule hardened (especially quenching), the internal organization retains more residual austenite, this residual austenite is unstable organization, storage and use of bearings process will continue to change, thus changing the accuracy of the cross bearing. Therefore the use of cold treatment process, it can reduce tissue retained austenite, slightly increase the hardness of parts.
2 Cold Process
Stay at room temperature after quenching: quenching, must make uniform cooling to room temperature inside and outside the ring after the cold treatment, or easy to crack, cooled to room temperature immediately after cold treatment (usually no more than 30min), otherwise it will abort the austenite to martensite changes.
Cold treatment temperature: the temperature of cold treatment based primarily on termination of martensitic transformation temperature of the steel Mf, while also considering the cold treatment on the mechanical properties and process and other factors.
For GCr15 steel, cold treatment selection -70 ℃; accuracy is not very high ferrule or equipment limitations, the cold treatment temperature optionally -40 ~ -70 ℃; super precision bearings in the -70 ℃ ~ -80 ℃ between the cold treatment. Cold temperatures affect the bearing life impact fatigue and exposure.
Cold insulation: Although a large number of martensite is cooled to a certain temperature Tilting moment to complete, but the number of rings to make both surface and core part cold treatment to achieve uniform temperature, requires a certain holding time, usually 1 to 1.5 h.
Cold treatment after tempering: ferrule on the air after the cold treatment, the temperature was slowly warmed to room temperature tempering timely manner. Temperature can not be too fast, or easy to crack; tempering timely, otherwise the internal ferrule large residual stresses can cause cracking rings, generally no more than 2h.
Bearing basic technical knowledge
Bearing joints: the sliding contact surface of the spherical, mainly applicable to swing movement, tilting movement and rotation of spherical plain bearings.
Bearings: a set of bearing two or more simultaneously by said bearing structure combination of rolling bearings. Such as needle roller and thrust cylindrical roller bearings, needle roller and thrust ball bearings, needle roller and angular contact ball bearings.
Other Bearings: In addition to the above other than the structure of the rolling bearing.
2, the bearing parts
Bearing parts: one consisting of the parts bearing, but does not include all the accessories.
Bearing rings: one or several raceway bearing to the heart of the annular parts.
Bearing washer: with one or several of the thrust bearing raceway ring parts.
Flat ring: a detachable substantially flat washer, use it as an inner or outer part of the radial cylindrical roller bearing outer or inner ring of a wall.
Thrust collar (detachable): a separable with "L" shaped cross-section ring, with the outer part of a radial cylindrical roller bearing inner ring of a wall.
In the ring: having two or more rows of rollers of a roller bearing inner ring separable used to isolate two rollers and guide rollers.
Snap ring: single port having a constant cross-section ring, mounted in a ring ditch, a roller bearing in the housing or shaft axial position.
Lock ring: single port with constant cross-section ring, mounted as a ring in a ring ditch rollers or cage will remain in the bearing.
Spacer: the annular parts, for the two bearing rings or bearing washer, or between the two halves or between the bearing rings between the two halves of the bearing washer, so that they are maintained between the axial distance required.
Seals: formed by one or several parts of the ring cap fixed to the bearing and a ferrule or the gasket ring or gasket in contact with another or to form a narrow gap labyrinth, prevent oil leakage and foreign matter.
Cover: is a ring cover, usually a thin metal plate stamping, a ring fixed to the bearing or washer and extending towards the other ring or gasket, cover bearing internal space, but not with another ring or gasket contacts
Bearings: a set of bearing two or more simultaneously by said bearing structure combination of rolling bearings. Such as needle roller and thrust cylindrical roller bearings, needle roller and thrust ball bearings, needle roller and angular contact ball bearings.
Other Bearings: In addition to the above other than the structure of the rolling bearing.
2, the bearing parts
Bearing parts: one consisting of the parts bearing, but does not include all the accessories.
Bearing rings: one or several raceway bearing to the heart of the annular parts.
Bearing washer: with one or several of the thrust bearing raceway ring parts.
Flat ring: a detachable substantially flat washer, use it as an inner or outer part of the radial cylindrical roller bearing outer or inner ring of a wall.
Thrust collar (detachable): a separable with "L" shaped cross-section ring, with the outer part of a radial cylindrical roller bearing inner ring of a wall.
In the ring: having two or more rows of rollers of a roller bearing inner ring separable used to isolate two rollers and guide rollers.
Snap ring: single port having a constant cross-section ring, mounted in a ring ditch, a roller bearing in the housing or shaft axial position.
Lock ring: single port with constant cross-section ring, mounted as a ring in a ring ditch rollers or cage will remain in the bearing.
Spacer: the annular parts, for the two bearing rings or bearing washer, or between the two halves or between the bearing rings between the two halves of the bearing washer, so that they are maintained between the axial distance required.
Seals: formed by one or several parts of the ring cap fixed to the bearing and a ferrule or the gasket ring or gasket in contact with another or to form a narrow gap labyrinth, prevent oil leakage and foreign matter.
Cover: is a ring cover, usually a thin metal plate stamping, a ring fixed to the bearing or washer and extending towards the other ring or gasket, cover bearing internal space, but not with another ring or gasket contacts
2013年8月23日星期五
Crossed roller bearings composition and characteristics
Crossed roller bearings are divided into two categories, one is a cross cylindrical roller bearings, another is a cross-tapered roller bearings. Cross roller bearings in a foreign country has a long history of application, while in the country is only in recent years before entering the public's sight, with its own characteristics and have other bearings incomparable superiority and well received by everyone be used.
Cross cylindrical roller bearings, having been split inner or outer ring, load rollers and spacer retainer after the Cross-Roller Ring and fastened together to prevent separated from each other, so when you install the cross roller bearing easy to operate. Since the rollers are arranged to cross, so only one set of Cross Roller Ring can bear loads in all directions, compared to conventional models, rigidity increased by 3 to 4 times. Meanwhile, imports bearing Cross cylindrical roller bearings Crossed roller bearings due to inner or outer ring is split in two, the bearing clearance adjustable, even if they are applied preload can be obtained with high precision rotary motion.
Crossed roller bearings Features:
1 operation simplifies installation
Standard cross roller bearing outer ring is divided into two parts, or inner, load roller and cage after being fixed together, you can fine tune the connection when installing bolts and mounting flange to achieve the desired load state Therefore, the installation operation is very simple.
2 bear large axial and radial loads
Because roller at 90 ° to the V-shaped groove raceway via a spacer retainer is arranged perpendicular to each other, this design makes cross roller bearings can withstand greater radial load, axial load and moment load and all the direction of the load.
3 installation space savings
Cross roller bearing outer ring size is minimal miniaturization, especially thin structure is close to the limit of small size, and high rigidity, so the most suitable for industrial robot joints or rotating parts, machining centers of rotation table, manipulator rotating part, precision rotary tables, medical equipment, measuring instruments, IC manufacturing equipment, etc. wide range of applications.
Cross cylindrical roller bearings, having been split inner or outer ring, load rollers and spacer retainer after the Cross-Roller Ring and fastened together to prevent separated from each other, so when you install the cross roller bearing easy to operate. Since the rollers are arranged to cross, so only one set of Cross Roller Ring can bear loads in all directions, compared to conventional models, rigidity increased by 3 to 4 times. Meanwhile, imports bearing Cross cylindrical roller bearings Crossed roller bearings due to inner or outer ring is split in two, the bearing clearance adjustable, even if they are applied preload can be obtained with high precision rotary motion.
Crossed roller bearings Features:
1 operation simplifies installation
Standard cross roller bearing outer ring is divided into two parts, or inner, load roller and cage after being fixed together, you can fine tune the connection when installing bolts and mounting flange to achieve the desired load state Therefore, the installation operation is very simple.
2 bear large axial and radial loads
Because roller at 90 ° to the V-shaped groove raceway via a spacer retainer is arranged perpendicular to each other, this design makes cross roller bearings can withstand greater radial load, axial load and moment load and all the direction of the load.
3 installation space savings
Cross roller bearing outer ring size is minimal miniaturization, especially thin structure is close to the limit of small size, and high rigidity, so the most suitable for industrial robot joints or rotating parts, machining centers of rotation table, manipulator rotating part, precision rotary tables, medical equipment, measuring instruments, IC manufacturing equipment, etc. wide range of applications.
Cross roller bearing surface rust work
Cross roller bearings in the preservation and operation of the process, because of its metal and the external environment, it is easy to produce rust. This not only greatly affect the running properties of the bearing, reduced efficiency. But also to the bearing life greatly reduced. cross roller bearing rust of the surface pretreatment methods:
1 Surface cleaning: cleaning rust must be in accordance with the nature of the surface and the prevailing conditions, select the appropriate method. Commonly used with solvent cleaning, chemical cleaning and mechanical cleaning treatment method.
2 available after the surface is dry clean filtered thrust cylindrical roller bearings drying compressed air, or by 120 ~ 170 ℃ of the drier, can also be wiped clean gauze.
Coated with anti-rust oil Method:
1 immersion method: Some small items using immersion in rust oils, allowed a layer of rust on the surface adhesion grease approach. Antirust film thickness can be controlled by the temperature or viscosity of the oil to achieve.
2 brushing method for NA immersion or spray outdoor construction equipment or special shape products, brush when it is necessary to pay attention not produce accumulation and pay attention coated to prevent leakage.
3 spray some large objects can rust oiled using immersion method, generally about 0.7Mpa pressure filter with compressed air spray cleaner place. Spray application of anti-rust oil or solvent dilution thin rust oil, but must adopt comprehensive fire protection and labor protection measures.
1 Surface cleaning: cleaning rust must be in accordance with the nature of the surface and the prevailing conditions, select the appropriate method. Commonly used with solvent cleaning, chemical cleaning and mechanical cleaning treatment method.
2 available after the surface is dry clean filtered thrust cylindrical roller bearings drying compressed air, or by 120 ~ 170 ℃ of the drier, can also be wiped clean gauze.
Coated with anti-rust oil Method:
1 immersion method: Some small items using immersion in rust oils, allowed a layer of rust on the surface adhesion grease approach. Antirust film thickness can be controlled by the temperature or viscosity of the oil to achieve.
2 brushing method for NA immersion or spray outdoor construction equipment or special shape products, brush when it is necessary to pay attention not produce accumulation and pay attention coated to prevent leakage.
3 spray some large objects can rust oiled using immersion method, generally about 0.7Mpa pressure filter with compressed air spray cleaner place. Spray application of anti-rust oil or solvent dilution thin rust oil, but must adopt comprehensive fire protection and labor protection measures.
2013年8月22日星期四
Bearing inspection and acceptance of the method
Check the bearing, the user must have the following knowledge:
(1) Which of the bearing commodities inspection standards based;
(2) What bearing commodities inspection items, why should test these items;
(3) bearing merchandise conducting quality inspection, you need to do to prepare the work, why should these preparations;
(4) the various test items bearing merchandise under what conditions, with what methods, what equipment to be tested, the test results must be within the tolerances in how to be qualified;
(5) bearing large quantities of goods and sometimes, not one hundred percent inspection, then it should be what kind of sampling plan, what quantity taken for examination in order to more fully with sufficient reliability to represent all the goods bearing the quality and inspection The result has to be measured according to what criteria to determine whether these products are qualified batch should be accepted or rejected should be unqualified approval.
Acceptance inspection of cross roller bearing can generally be divided into three categories, namely:
Routine check - bearing arrives routine general inspection.
Routine examination - of the bearing assembly associated with dimensional accuracy, precision rotation, bearing clearance and the bearing of the residual magnetic intensity of such items to be checked.
Special inspection - the quality of the bearing vibration, noise, quality and other specific requirements of the bearing to be checked.
(1) Which of the bearing commodities inspection standards based;
(2) What bearing commodities inspection items, why should test these items;
(3) bearing merchandise conducting quality inspection, you need to do to prepare the work, why should these preparations;
(4) the various test items bearing merchandise under what conditions, with what methods, what equipment to be tested, the test results must be within the tolerances in how to be qualified;
(5) bearing large quantities of goods and sometimes, not one hundred percent inspection, then it should be what kind of sampling plan, what quantity taken for examination in order to more fully with sufficient reliability to represent all the goods bearing the quality and inspection The result has to be measured according to what criteria to determine whether these products are qualified batch should be accepted or rejected should be unqualified approval.
Acceptance inspection of cross roller bearing can generally be divided into three categories, namely:
Routine check - bearing arrives routine general inspection.
Routine examination - of the bearing assembly associated with dimensional accuracy, precision rotation, bearing clearance and the bearing of the residual magnetic intensity of such items to be checked.
Special inspection - the quality of the bearing vibration, noise, quality and other specific requirements of the bearing to be checked.
Ball bearing vibration and noise reduction technology to improve its process equipment
At present, China deep groove ball bearing and seal products advanced internal structure parameters are almost identical, but such products in China vibration and noise levels are very different with foreign products, mainly in the manufacturing and working conditions factors. From the bearing industry point of view, condition factor can be solved reasonably requested by the host, and how to reduce the vibration caused by the manufacturer and the noise factor is the bearing industry must be addressed.
Many domestic and experiments show that: cage, ring, ball bearing vibration processing quality for different degrees of impact, where the processing quality ball bearing vibration impact on the most obvious, followed by processing quality rings, the most important influence factors and the ferrule ball roundness, waviness, roughness, surface bump and other injuries.
Ball products of the most prominent problem is the discrete vibration large, severe surface defects (single point, cluster points, pits, etc.), although the surface roughness, size, shape, the error level is not lower than the outside of the circle, but the co-sets After the bearing vibration value is high, and even produce different sound, the main problem is the waviness no control (no standards, no suitable test and analysis equipment), with an indication of poor vibration machine, grinding wheel, grinding disc, coolant, process parameters are problematic ; the other hand to improve the management level, to avoid the bump wounds, scratches, burns and other machines of any quality problems.
For the rings, the most serious impact of bearing vibration is channel waviness and surface roughness. For example, small and medium deep groove ball bearing inner channel roundness greater than 2μm, the bearing vibration will have a significant impact, both inside and outside the channel waviness greater than 0.7μm, the bearing vibration value increases with the waviness of the channel serious gouges Vibration can rise more than 4dB, and even different sound.
Both balls or rings, waviness produced in the grinding, although Superfinishing waviness can improve and reduce roughness, but the most fundamental measure is to reduce the ultra-fine grinding process of waviness, to avoid randomness bump hurt, there are two main measures:
First, reduce the rolling surface vibration when ultra-fine grinding, get a good surface finish shape accuracy and surface texture quality in order to reduce vibration, grinding super machine must have good vibration resistance, bed and other important structural parts with vibration absorption, ultra- Whetstone fine machine oscillating system has a good anti-vibration performance; improve grinding speed, grinding abroad commonly used outer raceway 6202 60,000 spindle, grinding speed 60m / s or more, domestic general much lower, mainly due to the spindle and main bearing performance limitations. In high-speed grinding, grinding force is small, thin grinding deterioration is not easy to burn, and can improve the precision and efficiency, low noise ball bearing great influence; spindle stiffness and movement speed characteristics of the low-noise ball bearing a great influence on the grinding vibration, the higher the stiffness, grinding speed on the grinding force change, the less sensitive to vibration grinding system smaller; improve spindle bearing support stiffness, random balancing technology to improve the grinding spindle vibration sex. Foreign grinding vibration velocity (eg Gamfior) is approximately one-tenth of the domestic general spindle; improve cutting and grinding wheel dressing Whetstone quality is essential. China's current wheel Whetstone main problem is poor uniformity organizational structure, seriously affecting the ultra-low-noise ball bearing grinding machining quality; sufficiently cooled, improve filtering accuracy; improve the feed to the system fine resolution, reduce the feed inertia; reasonable wear ultra-processing process parameters and machining processes are factors that can not be ignored, grinding amount to small, strictly geometric tolerance, small diameter ball bearings should not use Superfinishing, coarse grinding super not be separated to ensure good surface quality.
Second is to improve machining plane precision grinding and superfinishing process reduces error reflection of the outer end face grinding and super positioning reference during processing. The channel diameter ultra-fine error reflection on the ditch by OD grinding, grinding on the ditch ditch super error reflection indirect transitive. If the workpiece in the transfer process produces bump injury, will be directly mapped to the raceway complex machined surface, the impact of bearing vibration. So you must take the following measures: improve the positioning reference surface shape accuracy; processing passes smoothly and without a bump hurt; rough allowance form and position errors can not be too large, especially in the remaining amount is small, too large error will cause the final grinding and ultra-fine close to the final shape accuracy has not improved the quality requirements, seriously affecting the processing quality consistency.
Many domestic and experiments show that: cage, ring, ball bearing vibration processing quality for different degrees of impact, where the processing quality ball bearing vibration impact on the most obvious, followed by processing quality rings, the most important influence factors and the ferrule ball roundness, waviness, roughness, surface bump and other injuries.
Ball products of the most prominent problem is the discrete vibration large, severe surface defects (single point, cluster points, pits, etc.), although the surface roughness, size, shape, the error level is not lower than the outside of the circle, but the co-sets After the bearing vibration value is high, and even produce different sound, the main problem is the waviness no control (no standards, no suitable test and analysis equipment), with an indication of poor vibration machine, grinding wheel, grinding disc, coolant, process parameters are problematic ; the other hand to improve the management level, to avoid the bump wounds, scratches, burns and other machines of any quality problems.
For the rings, the most serious impact of bearing vibration is channel waviness and surface roughness. For example, small and medium deep groove ball bearing inner channel roundness greater than 2μm, the bearing vibration will have a significant impact, both inside and outside the channel waviness greater than 0.7μm, the bearing vibration value increases with the waviness of the channel serious gouges Vibration can rise more than 4dB, and even different sound.
Both balls or rings, waviness produced in the grinding, although Superfinishing waviness can improve and reduce roughness, but the most fundamental measure is to reduce the ultra-fine grinding process of waviness, to avoid randomness bump hurt, there are two main measures:
First, reduce the rolling surface vibration when ultra-fine grinding, get a good surface finish shape accuracy and surface texture quality in order to reduce vibration, grinding super machine must have good vibration resistance, bed and other important structural parts with vibration absorption, ultra- Whetstone fine machine oscillating system has a good anti-vibration performance; improve grinding speed, grinding abroad commonly used outer raceway 6202 60,000 spindle, grinding speed 60m / s or more, domestic general much lower, mainly due to the spindle and main bearing performance limitations. In high-speed grinding, grinding force is small, thin grinding deterioration is not easy to burn, and can improve the precision and efficiency, low noise ball bearing great influence; spindle stiffness and movement speed characteristics of the low-noise ball bearing a great influence on the grinding vibration, the higher the stiffness, grinding speed on the grinding force change, the less sensitive to vibration grinding system smaller; improve spindle bearing support stiffness, random balancing technology to improve the grinding spindle vibration sex. Foreign grinding vibration velocity (eg Gamfior) is approximately one-tenth of the domestic general spindle; improve cutting and grinding wheel dressing Whetstone quality is essential. China's current wheel Whetstone main problem is poor uniformity organizational structure, seriously affecting the ultra-low-noise ball bearing grinding machining quality; sufficiently cooled, improve filtering accuracy; improve the feed to the system fine resolution, reduce the feed inertia; reasonable wear ultra-processing process parameters and machining processes are factors that can not be ignored, grinding amount to small, strictly geometric tolerance, small diameter ball bearings should not use Superfinishing, coarse grinding super not be separated to ensure good surface quality.
Second is to improve machining plane precision grinding and superfinishing process reduces error reflection of the outer end face grinding and super positioning reference during processing. The channel diameter ultra-fine error reflection on the ditch by OD grinding, grinding on the ditch ditch super error reflection indirect transitive. If the workpiece in the transfer process produces bump injury, will be directly mapped to the raceway complex machined surface, the impact of bearing vibration. So you must take the following measures: improve the positioning reference surface shape accuracy; processing passes smoothly and without a bump hurt; rough allowance form and position errors can not be too large, especially in the remaining amount is small, too large error will cause the final grinding and ultra-fine close to the final shape accuracy has not improved the quality requirements, seriously affecting the processing quality consistency.
2013年8月21日星期三
Slewing ring in the course of maintenance
slewing bearing use there will be some problems, the following Xiaobian to introduce you to slewing in use and maintenance.
1, the receipt of the product should be enabled depending on the working conditions and re-filled with new grease.
2, according to the different types of slewing bearings, slewing bearings should be greased regularly,
3, the use of the process should be regularly cleared slewing bearing surface debris, check the slewing ring seal is aging, cracking, breakage or detachment, if one of them happens, seals should be replaced to prevent debris entering the inner raceway and grease loss, replacement grease should be applied accordingly to avoid rolling elements and raceways nap stuck or rusted.
4, because in the course of comprehensive factors, the user can choose according to their own specific situation best grease
7, slewing ring in use, not use water erosion slewing ring and avoid the water into the raceway caused by rust; hard to prevent foreign objects approaching or entering the mating area, so as to avoid tooth injury or unnecessary trouble.
1, the receipt of the product should be enabled depending on the working conditions and re-filled with new grease.
2, according to the different types of slewing bearings, slewing bearings should be greased regularly,
3, the use of the process should be regularly cleared slewing bearing surface debris, check the slewing ring seal is aging, cracking, breakage or detachment, if one of them happens, seals should be replaced to prevent debris entering the inner raceway and grease loss, replacement grease should be applied accordingly to avoid rolling elements and raceways nap stuck or rusted.
4, because in the course of comprehensive factors, the user can choose according to their own specific situation best grease
7, slewing ring in use, not use water erosion slewing ring and avoid the water into the raceway caused by rust; hard to prevent foreign objects approaching or entering the mating area, so as to avoid tooth injury or unnecessary trouble.
Slewing definition and basic structure
slewing bearing in the real industrial applications is very wide, known as: "the machine joints" is required between two objects in relative rotary movement, and the need to bear axial force, radial force, overturning moment of machinery necessary and important driving originals. With the rapid development of the machinery industry, slewing ring in the ship's equipment, engineering machinery, light machinery, metallurgical machinery, medical equipment, industrial robots, tunnel boring machines, rotary stage lighting industry has been widely used.
Slewing usually worm, slewing ring, shell, motor and other parts. As the core components using slewing, it can withstand the axial force, radial force, overturning moment. Its many forms, but basically similar structure and composition.
Slewing usually worm, slewing ring, shell, motor and other parts. As the core components using slewing, it can withstand the axial force, radial force, overturning moment. Its many forms, but basically similar structure and composition.
2013年8月20日星期二
Rolling type selection
Rolling type selection Abstract: China's CNC machine tool industry, urgently develop mechanical components function classes commonly used English: processing methods Yantai Universal Group launched CNC turret high speed steel smelting MSC.ADAMS an MPV based on improved handling and stability analysis of one kind New high-precision mold material commonly used in Beijing advent R14 system variable is set skill vigilance "NC Education" overheating EDM discharge mechanism of TC4 titanium alloy combined machine tools and automatic line technology trends guru's skills can not be lost with the SiAlON ceramic tool efficient milling of cast iron Yangzhou University successfully developed non-circular rings CNC lathe programming source curve quarter ellipse What is CAD? Can compensate for wear of the cutting edge is not shovel tooth milling cutter design and manufacture of high-efficiency small lathe features Japanese VB-based environment shaper cutters CADProCAM - professional multi-axis CNC machining positioning error differential bearing life calculation method to choose the type of basic role of contact with basic concepts of relative deformation term life of a rolling bearing a gasket material appeared a sign of fatigue propagation relative to the other before a washer washer rpm reliable bearing life and reliable operation of a group of nearly the same conditions on the same bearing expect to achieve than the specified percentage of single bearing life reliable bearing service life of more than required load bearing washer relative probability.
(A) the basic concepts and terminology
A life
Means a set of bearings, one ring (or washer) or rolling of the material appeared before the first signs of fatigue propagation, a ring (or washer) relative to the other ring (or washer) the number of revolutions.
2, reliability (ie, the reliability of bearing life)
Refers to a group of operating under the same conditions, nearly the same expected bearing life reaches or exceeds the specified percentage. The reliability of a single rolling bearing that meet or exceed the lifetime probability.
3, static load
When the bearing ring or gasket when the relative rotational speed is zero (or the thrust bearing to the heart) or when the direction of the rolling element raceway when no motion (linear bearings), the load acting on the bearing.
4, static and dynamic load
When the bearing ring or gasket when the relative rotation (to the heart or thrust bearings) or when the roll bearings element in the rolling direction of movement (linear bearings), the load acting on the bearing.
5, rated life
Radial or axial basic dynamic load rating Basic dynamic load rating based on the life of the predicted value.
6, the basic rating life
Reliability associated with 90% of rated life.
7, the radial basic dynamic load rating
Means a set of rolling bearings can withstand the constant imaginary radial loads, loads in the basic rating life of one million rpm. The single row angular contact bearings, this load causes the bearing rings to each other is purely radial displacement is generated between the radial component of the load.
8, the axial basic dynamic load rating
Refers to the hypothetical role of the center in a constant bearing axial load bearing loads in the basic rating life of one million rpm.
9, radial (or axial) equivalent dynamic load
Refers to a constant radial load (or central axial load), the load, the rolling bearing having the same load of the actual life.
10, radial (or axial) Basic static load rating
Means with a rolling body raceways, and the total amount of permanent deformation corresponding radial static load (or the central axis of the static load). If at zero load, roller and raceway (roller bearing) is assumed to be normal or bus (line contacts) when the maximum contact stress, the rolling element and raceway contact produces a total permanent deformation of the rolling element diameter of 1/10000. For single row angular contact bearings, radial load rating of the bearing rings relative to each other due to pure radial displacement of the radial component of the load.
11, radial (or axial) Static equivalent load
The radial static load (or central axial static load) causes the maximum stress by rolling element and raceway contact at the total amount of permanent deformation resulting from the actual load conditions the same as the total amount of permanent deformation.
(A) the basic concepts and terminology
A life
Means a set of bearings, one ring (or washer) or rolling of the material appeared before the first signs of fatigue propagation, a ring (or washer) relative to the other ring (or washer) the number of revolutions.
2, reliability (ie, the reliability of bearing life)
Refers to a group of operating under the same conditions, nearly the same expected bearing life reaches or exceeds the specified percentage. The reliability of a single rolling bearing that meet or exceed the lifetime probability.
3, static load
When the bearing ring or gasket when the relative rotational speed is zero (or the thrust bearing to the heart) or when the direction of the rolling element raceway when no motion (linear bearings), the load acting on the bearing.
4, static and dynamic load
When the bearing ring or gasket when the relative rotation (to the heart or thrust bearings) or when the roll bearings element in the rolling direction of movement (linear bearings), the load acting on the bearing.
5, rated life
Radial or axial basic dynamic load rating Basic dynamic load rating based on the life of the predicted value.
6, the basic rating life
Reliability associated with 90% of rated life.
7, the radial basic dynamic load rating
Means a set of rolling bearings can withstand the constant imaginary radial loads, loads in the basic rating life of one million rpm. The single row angular contact bearings, this load causes the bearing rings to each other is purely radial displacement is generated between the radial component of the load.
8, the axial basic dynamic load rating
Refers to the hypothetical role of the center in a constant bearing axial load bearing loads in the basic rating life of one million rpm.
9, radial (or axial) equivalent dynamic load
Refers to a constant radial load (or central axial load), the load, the rolling bearing having the same load of the actual life.
10, radial (or axial) Basic static load rating
Means with a rolling body raceways, and the total amount of permanent deformation corresponding radial static load (or the central axis of the static load). If at zero load, roller and raceway (roller bearing) is assumed to be normal or bus (line contacts) when the maximum contact stress, the rolling element and raceway contact produces a total permanent deformation of the rolling element diameter of 1/10000. For single row angular contact bearings, radial load rating of the bearing rings relative to each other due to pure radial displacement of the radial component of the load.
11, radial (or axial) Static equivalent load
The radial static load (or central axial static load) causes the maximum stress by rolling element and raceway contact at the total amount of permanent deformation resulting from the actual load conditions the same as the total amount of permanent deformation.
Single row angular contact ball bearings and double row angular contact ball bearings
Single row angular contact ball bearings and double row angular contact ball bearing Abstract: ultra-high-speed milling Ways What fuse, its role is to what? pro / e part accuracy modify Haoke welding stress relieving equipment in natural gas project on the application of expert systems MCE Cyclone content selection CNC machining high precision machining techniques and tools shank system selection three good technology extrusion die Eight new technologies upcoming CNC servo system performance tools to explore Taiwan Factory call up profits will ascribed CNC milling technology perspective advanced measurement technology and new trends in the correct milling tooth spur gear to ensure proper planing point Zatan class machine - fast curing rubber broaching Introduction Technical R1-00 automatic feeding tipping rules CNC EDM wire cutting in plastic processing application method and machining centers CNC Troubleshooting Q digital oscilloscope using a mold manufacturing high-speed cutting tools contact bearing load bearing system can be configured to represent this installation code contact ball bearings ball retainer inner integral outer radial load axial load Axial load speed work stably single contact ball bearings can withstand an axial direction load bearing radial load rolling loads radial load is not the same radial plane generates an internal axial force component must be installed in pairs using a ..
Angular contact ball bearings 70000 type, and from the outer ring, inner ring, balls, cage. Can support radial load and axial load can also be subject to pure axial load, at higher speeds and stable work. Single row angular contact ball bearings can withstand axial load in one direction. Such bearings under pure radial load, due to the rolling load line and not in the same line of action of the radial load radial plane, an internal axial component, it must be installed in pairs.
A single row angular contact ball bearings Single row angular contact ball bearings have the following structure:
(1) Separate angular contact ball bearings
This bearing the code S70000, its outer ring raceway side did not lock port, with the inner ring, cage, Gang ball component separation, which can be installed separately. Such are mostly less than 10mm diameter miniature bearings for gyro rotors, micro-motors for balancing, noise, vibration, stability requirements are high device.
(2) non-separable angular contact ball bearings
These bearings have a lock ring channel mouth, so the two can not be separated circles. At a contact angle is divided into three types:
① contact angle α = 40 °, applicable to withstand large axial load;
② contact angle α = 25 °, used for precision spindle bearings;
③ contact angle α = 15 °, and more for larger sized precision bearings.
(3) arranged in pairs of angular contact ball bearings
Arranged in pairs of angular contact ball bearings for both radial and axial load settings, they can withstand pure radial load and axial load in either direction. Such bearings by the manufacturer according to certain pre-load requirements, matching pairs, available to users. When the bearing is installed on the machine after fastening, completely eliminating the bearing clearance, and to outline the ball is preload rings and state, thus increasing the combined bearing steel.
Arranged in pairs of angular contact ball bearings, there are three different configurations Type:
① back to back configuration, the post code for the DB (eg 70000/DB), this configuration of the steel better withstand the overturning moment of the performance is good, the bearings can withstand axial load;
② face configuration, the post code for the DF (eg 70000/DF), this configuration of the rigidity and the ability to withstand the overturning moment as DB configuration form, bearings can withstand axial load;
③ series configuration, post code for DT (eg 70000/DT), this configuration can also be supported in the same place in series of three or more bearings, but can only bear axial load in one direction. Generally, to balance and limit the axial displacement, the other bearing at the other direction to be installed to withstand the axial load bearing.
In addition, there is a pair for any single row angular contact ball bearings. This bearing special processing, can be two back to back, face to face or two tandem two other arbitrary combinations, paired combination of axial clearance can be selected, post code CA represents a smaller axial clearance, CB represents the axial clearance is moderate, CC represents a larger axial clearance.
Universal paired bearings can also be configured to use requirements have preloaded bearings, and after-code GA, GB, GC representation. GA represents paired with smaller preloaded; GB represents paired with moderate preloaded; GC indicates a greater paired preloaded.
2 double row angular contact ball bearings
Double row angular contact ball bearings can be characterized by both radial and axial load of joint load, limiting both the axis of the axial displacement. Compared with the two-way thrust ball bearings, this bearing high speed limit, the contact angle of 32 °, rigid, and can withstand the overturning moment, widely used in cars in the front wheel hub (some models also use the same size double row tapered roller bearings).
Double row angular contact ball bearing structure has four variants:
(1) A type of bearing outside diameter less than or equal to 90mm standard design. Non-loaded ball gap, so they can withstand the equivalent of two-way axial load. Using lightweight glass fiber reinforced nylon 66 cage, bearing temperature rise is small.
(2) A type of bearing outside diameter greater than 90mm standard design. Side of the ball gap, with a pressed steel cage or solid brass cage.
(3) E-type structure is enhanced, the side with filling slots that can hold more of the ball, so the higher carrying capacity.
(4) sides with a dust cover type and sides with a ring-type A-type and E-type design designed double row angular contact ball bearings can be on both sides with a dust cover (non-contact) or seal (contact ). Sealed bearings are filled with rust inside lithium grease, operating temperature is generally -30 ~ +110 ℃. No further lubrication during use, should not be heated before installation should not be cleaned.
Double row angular contact ball bearing installation should pay attention, although bearings can withstand axial load, but if there is one side of the gap when the ball should be careful not to let the main axial load through the notched side of the gutter.
Angular contact ball bearings 70000 type, and from the outer ring, inner ring, balls, cage. Can support radial load and axial load can also be subject to pure axial load, at higher speeds and stable work. Single row angular contact ball bearings can withstand axial load in one direction. Such bearings under pure radial load, due to the rolling load line and not in the same line of action of the radial load radial plane, an internal axial component, it must be installed in pairs.
A single row angular contact ball bearings Single row angular contact ball bearings have the following structure:
(1) Separate angular contact ball bearings
This bearing the code S70000, its outer ring raceway side did not lock port, with the inner ring, cage, Gang ball component separation, which can be installed separately. Such are mostly less than 10mm diameter miniature bearings for gyro rotors, micro-motors for balancing, noise, vibration, stability requirements are high device.
(2) non-separable angular contact ball bearings
These bearings have a lock ring channel mouth, so the two can not be separated circles. At a contact angle is divided into three types:
① contact angle α = 40 °, applicable to withstand large axial load;
② contact angle α = 25 °, used for precision spindle bearings;
③ contact angle α = 15 °, and more for larger sized precision bearings.
(3) arranged in pairs of angular contact ball bearings
Arranged in pairs of angular contact ball bearings for both radial and axial load settings, they can withstand pure radial load and axial load in either direction. Such bearings by the manufacturer according to certain pre-load requirements, matching pairs, available to users. When the bearing is installed on the machine after fastening, completely eliminating the bearing clearance, and to outline the ball is preload rings and state, thus increasing the combined bearing steel.
Arranged in pairs of angular contact ball bearings, there are three different configurations Type:
① back to back configuration, the post code for the DB (eg 70000/DB), this configuration of the steel better withstand the overturning moment of the performance is good, the bearings can withstand axial load;
② face configuration, the post code for the DF (eg 70000/DF), this configuration of the rigidity and the ability to withstand the overturning moment as DB configuration form, bearings can withstand axial load;
③ series configuration, post code for DT (eg 70000/DT), this configuration can also be supported in the same place in series of three or more bearings, but can only bear axial load in one direction. Generally, to balance and limit the axial displacement, the other bearing at the other direction to be installed to withstand the axial load bearing.
In addition, there is a pair for any single row angular contact ball bearings. This bearing special processing, can be two back to back, face to face or two tandem two other arbitrary combinations, paired combination of axial clearance can be selected, post code CA represents a smaller axial clearance, CB represents the axial clearance is moderate, CC represents a larger axial clearance.
Universal paired bearings can also be configured to use requirements have preloaded bearings, and after-code GA, GB, GC representation. GA represents paired with smaller preloaded; GB represents paired with moderate preloaded; GC indicates a greater paired preloaded.
2 double row angular contact ball bearings
Double row angular contact ball bearings can be characterized by both radial and axial load of joint load, limiting both the axis of the axial displacement. Compared with the two-way thrust ball bearings, this bearing high speed limit, the contact angle of 32 °, rigid, and can withstand the overturning moment, widely used in cars in the front wheel hub (some models also use the same size double row tapered roller bearings).
Double row angular contact ball bearing structure has four variants:
(1) A type of bearing outside diameter less than or equal to 90mm standard design. Non-loaded ball gap, so they can withstand the equivalent of two-way axial load. Using lightweight glass fiber reinforced nylon 66 cage, bearing temperature rise is small.
(2) A type of bearing outside diameter greater than 90mm standard design. Side of the ball gap, with a pressed steel cage or solid brass cage.
(3) E-type structure is enhanced, the side with filling slots that can hold more of the ball, so the higher carrying capacity.
(4) sides with a dust cover type and sides with a ring-type A-type and E-type design designed double row angular contact ball bearings can be on both sides with a dust cover (non-contact) or seal (contact ). Sealed bearings are filled with rust inside lithium grease, operating temperature is generally -30 ~ +110 ℃. No further lubrication during use, should not be heated before installation should not be cleaned.
Double row angular contact ball bearing installation should pay attention, although bearings can withstand axial load, but if there is one side of the gap when the ball should be careful not to let the main axial load through the notched side of the gutter.
2013年8月19日星期一
The use of bearings
Rolling bearings are precision components, and its use should also be carefully carried out accordingly. No matter how high-performance bearings, if used improperly, it will not get the expected performance. Note the use of the relevant bearing as follows:
1, to keep the roll bearings and the surrounding clean.
Even the eyes can not see small dust, will give adversely affect the bearings.
2, carefully use.
Bearing in use will have a strong impact suffered bruises and indentation, cause of the accident.
3, using the appropriate operating tool.
Avoid the existing tools instead, you must use the right tools.
4, pay attention to corrosion of bearings.
Operation will become rusty hands sweat reason to pay attention to clean hands operation, the best possible wear gloves.
1, to keep the roll bearings and the surrounding clean.
Even the eyes can not see small dust, will give adversely affect the bearings.
2, carefully use.
Bearing in use will have a strong impact suffered bruises and indentation, cause of the accident.
3, using the appropriate operating tool.
Avoid the existing tools instead, you must use the right tools.
4, pay attention to corrosion of bearings.
Operation will become rusty hands sweat reason to pay attention to clean hands operation, the best possible wear gloves.
Bearing Installation
Bearing is installed correctly, affecting accuracy, longevity, performance. Therefore, the design and installation of the bearing assembly department to be adequately studied. I hope to be in accordance with the operating standards for installation. The projects are usually operating standards are as follows:
1, cleaning bearings and related components
2, Check the connected components of size and precision machining conditions
3, the installation
4, check the cross bearing installed
5, the supply of lubricant
Recommend the use of open bearings package just before installation to prevent rust.
Bearing installation method due to the bearing structure, with the condition varies, in general, due to multi-axis rotation, so the inner ring needs interference fit. Cylindrical bore bearings, multi-pressed into the press or by thermal loading method. Cone of the occasion, mounted directly on the tapered shaft or sleeve installation. Most types of bearings are generally installed using the following method:
1, pressed into the press method
2, the thermal loading methods
3, the cooling method
In addition, also the use of advanced electromagnetic induction heating device for installation in a short time without fire, uniform heating oil, cleaner and more efficient installation. Please refer to the Division I bearing heater bearing removal bearing removal, is regular maintenance, when bearing replacement. After the demolition, if you want to continue to use or need to check the bearing of the state, its removal and installation should be carried out as carefully. Careful not to damage the bearings and the parts, especially the interference fit bearing removal, the operation is difficult, it is necessary to pay attention to. Bearing removal can be used presses, drawing fixtures, extrusion screws, induction heating equipment, hydraulic and other several ways.
1, cleaning bearings and related components
2, Check the connected components of size and precision machining conditions
3, the installation
4, check the cross bearing installed
5, the supply of lubricant
Recommend the use of open bearings package just before installation to prevent rust.
Bearing installation method due to the bearing structure, with the condition varies, in general, due to multi-axis rotation, so the inner ring needs interference fit. Cylindrical bore bearings, multi-pressed into the press or by thermal loading method. Cone of the occasion, mounted directly on the tapered shaft or sleeve installation. Most types of bearings are generally installed using the following method:
1, pressed into the press method
2, the thermal loading methods
3, the cooling method
In addition, also the use of advanced electromagnetic induction heating device for installation in a short time without fire, uniform heating oil, cleaner and more efficient installation. Please refer to the Division I bearing heater bearing removal bearing removal, is regular maintenance, when bearing replacement. After the demolition, if you want to continue to use or need to check the bearing of the state, its removal and installation should be carried out as carefully. Careful not to damage the bearings and the parts, especially the interference fit bearing removal, the operation is difficult, it is necessary to pay attention to. Bearing removal can be used presses, drawing fixtures, extrusion screws, induction heating equipment, hydraulic and other several ways.
Bearing operation precautions
Listen checks the status of the machine operation and prepare a thorough inspection plans has become increasingly important. Among them, the bearing is the focus of attention, because it is the most important of all the machines rotating parts. Use hearing to identify irregular operation is a very common method, if the bearing is in good operating condition, it emits low whining sound; if a sharp hissing sound, squeaking sound, and other irregular sounds, usually the bearing is in poor running condition. How to listen? The old method: Use a stick or screwdriver against the bearing housing and the other end affixed to live ears; advanced methods: the use of advanced equipment, such as electronic monitoring equipment status, pre-diagnosis of the functioning of the bearing.
Touch
If the roll bearings temperature over 125 ℃ long-term operation, will reduce bearing life, high temperature bearings are often expressed in an abnormal condition, causing high temperatures reasons: lack of lubrication or excessive lubrication, the lubricant containing impurities, the load is too large, bearing damage, lack of space, and seal friction generated by the high and so on. Therefore, detection of bearing temperature is necessary, either by itself or other important measuring bearing parts. The old way is to touch the bearing housing temperature sensation, now by means of a temperature probe, which can accurately measure the temperature of the bearings and displayed in order to effectively take protective measures.
Observation
If you get a good bearing lubrication and proper debris and moisture barrier, which means that there should be no oil seal wear. However, the best in the open bearing box to visually inspect the bearings and regularly check seals. Check the status near the bearings seals to ensure that they are sufficient to prevent the hot liquids or corrosive liquids or gases penetrate along the bearing axis. Protection ring and labyrinth seals should be coated with grease to ensure maximum protective effect, seal If wear should be replaced soon.
Touch
If the roll bearings temperature over 125 ℃ long-term operation, will reduce bearing life, high temperature bearings are often expressed in an abnormal condition, causing high temperatures reasons: lack of lubrication or excessive lubrication, the lubricant containing impurities, the load is too large, bearing damage, lack of space, and seal friction generated by the high and so on. Therefore, detection of bearing temperature is necessary, either by itself or other important measuring bearing parts. The old way is to touch the bearing housing temperature sensation, now by means of a temperature probe, which can accurately measure the temperature of the bearings and displayed in order to effectively take protective measures.
Observation
If you get a good bearing lubrication and proper debris and moisture barrier, which means that there should be no oil seal wear. However, the best in the open bearing box to visually inspect the bearings and regularly check seals. Check the status near the bearings seals to ensure that they are sufficient to prevent the hot liquids or corrosive liquids or gases penetrate along the bearing axis. Protection ring and labyrinth seals should be coated with grease to ensure maximum protective effect, seal If wear should be replaced soon.
2013年8月17日星期六
Deep groove ball bearing vibration noise root causes
Deep groove ball bearing vibration and noise on the formation mechanism of domestic and international aspects of the control of vibration and noise, there are two different approaches. Bearing vibration mainly from two sources:
One bearing bearing caused by external incentives inherent vibration, referring to the bearing inner ring, outer ring, rolling elements and cage the natural vibration.
Two deep groove ball bearing due to contact between moving parts forced vibration caused by collision, such as ball rolling is not an ideal sphere, inside and outside the channel contact point trajectory is not a perfect circle (roundness, waviness), the raceway not the ideal smooth surface (roughness) and the rolling elements and cage in motion collision and lubricants in the forced vibration caused by impurities, vibration and sound are closely related, but slightly different sense, That is the sound originated in vibration, acoustic vibrations in the air is transmitted to humans by the feeling of hearing, so the ultra-high frequency vibrations are inaudible. However, if the receiver and the sound vibration characteristics of the receiver is the same, two received signals received relevant to the whole, according to this view, controlling vibration or noise control can play the same effect. And because the vibration control is simple, so home and abroad priority control vibration to ensure product quality. Therefore, for the general bearing, it is recommended to concentrate its limited human and financial resources to do a good job of bearing vibration control. Quality standards should not separate the noise, of course, according to foreign experience for a special bearing products, such as computer hard drives, CD recorder drive system bearings, vibration assessment is not easy to use, can develop criteria to assess noise measurement method .
One bearing bearing caused by external incentives inherent vibration, referring to the bearing inner ring, outer ring, rolling elements and cage the natural vibration.
Two deep groove ball bearing due to contact between moving parts forced vibration caused by collision, such as ball rolling is not an ideal sphere, inside and outside the channel contact point trajectory is not a perfect circle (roundness, waviness), the raceway not the ideal smooth surface (roughness) and the rolling elements and cage in motion collision and lubricants in the forced vibration caused by impurities, vibration and sound are closely related, but slightly different sense, That is the sound originated in vibration, acoustic vibrations in the air is transmitted to humans by the feeling of hearing, so the ultra-high frequency vibrations are inaudible. However, if the receiver and the sound vibration characteristics of the receiver is the same, two received signals received relevant to the whole, according to this view, controlling vibration or noise control can play the same effect. And because the vibration control is simple, so home and abroad priority control vibration to ensure product quality. Therefore, for the general bearing, it is recommended to concentrate its limited human and financial resources to do a good job of bearing vibration control. Quality standards should not separate the noise, of course, according to foreign experience for a special bearing products, such as computer hard drives, CD recorder drive system bearings, vibration assessment is not easy to use, can develop criteria to assess noise measurement method .
Seal type deep groove ball bearings
Many deep groove ball bearing sealing problems mainly ineffective drain grease and dust, etc., in a nutshell is poor sealing performance; non-contact seals no big problem, the main problem is multi-contact seals. What are the causes it?
Main bearing seal structure is relatively backward. Seal structure lies in the rotary member of the seal groove and the sealing cap sealing lips. Sealed general there are three forms, one does not actually slot; second is a small inner diameter, there is a step; third is a complete seal groove.
Sealing lip with a single and double lip of the points, to improve the sealing effect, we believe that the sealing lips should be developed and groove seal structure, because this form of contact seals and labyrinth seals combined sealing effect is better, but the process is complicated, higher cost.
In the modern enterprise in the pursuit of cost-premise, as far as possible the pursuit of double lip seal and groove seal structure deep groove ball bearings, but conditions were not under seal structure can only produce a general, after all, is now a large domestic use part of the sealing structure in general, and the sealing structure by many users.
Main bearing seal structure is relatively backward. Seal structure lies in the rotary member of the seal groove and the sealing cap sealing lips. Sealed general there are three forms, one does not actually slot; second is a small inner diameter, there is a step; third is a complete seal groove.
Sealing lip with a single and double lip of the points, to improve the sealing effect, we believe that the sealing lips should be developed and groove seal structure, because this form of contact seals and labyrinth seals combined sealing effect is better, but the process is complicated, higher cost.
In the modern enterprise in the pursuit of cost-premise, as far as possible the pursuit of double lip seal and groove seal structure deep groove ball bearings, but conditions were not under seal structure can only produce a general, after all, is now a large domestic use part of the sealing structure in general, and the sealing structure by many users.
2013年8月10日星期六
Crossed roller bearings how to adjust in order to achieve the best results
Bearing is the basis of the quality of its own, through the bearing steel, cross roller bearing and crafts strict customs, the production out of the bearing quality is absolutely the best. But why will still see some of the questions about the damage it? This is mainly because the use of inattention caused, not seen since the bearing itself quality problems caused.
Through a combination of bearing failure and deterioration, performance status parameters to determine and predict the reliability and performance of the bearing, the site of the abnormal situation, causes and degree of risk identification and judgment to decide restoration and improvement of the integrated technology. Therefore, the bearing fault diagnosis technology is not a simple fault detection (or monitoring) technology, nor is it a simple point inspection instrumentation. Correctly, quickly and effectively signal acquisition, data processing, manual or automatic identification and judgment. In order to determine the scientific repair cycle, the mechanism should be based on various types of failure, fatigue, wear life tests and estimates necessary.
1, the shaft and the bearing housing tolerances choice and control: after pressure block has no bearing swivel sense of flexibility. If significant rotation is not flexible, then the shaft size is too large, and decreased tolerance. Such as bearings pressed into the hand after the obvious "imperfections" in a certain sense the steering shaft, it may be too round shaft or shaft tolerance is not good. A good shaft and bearing tolerances in the control room, so it should be controlled roundness.
2, the bearing assembly mode: Because bearings are precision products, such as improper assembly, easy to damage the channel bearings, resulting in bearing damage. Bearing in the assembly, there should be a special mold, can not beat, pushing the axial force can only be a small circle, the press force only when the circle. Assembly requires the use of pneumatic or hydraulic crimping die down when outside the country level, if the channel slope will lead cross roller bearing damage due to power, leaving the production of bearing guide ring.
3, the assembly to prevent foreign bodies: Bearing mounted rotor balancing is very susceptible to the iron homeostasis Before installing the bearings, so it is best to do balancing. Bearing in the conference room to put some oil or grease lubrication, but operators often difficult to control the amount of oil or grease the bearings if the plot to stay indoors, it's easy to rotate along the axis cross roller bearing. Bearing chamber is preferably not coated with oil or grease, such as non-coated control, without bearing to stay indoors.
4, paint rust prevention: paint rust is featured in a sealed motor, in the General Assembly multiple motors sounds good, but after a period of storage, the motor becomes a very unusual sound, remove the bearing severe rust. Many manufacturers will be considered before the cross roller bearing problems, now the main electrical plant has been aware of the problem of varnish. The main problem is that out of the insulating paint volatile acid at a certain temperature, humidity, corrosion and protection of metals, formation of corrosive substances, channels skf bearing cause corrosion damage. The only problem now is to choose a good varnish, dry air for some time after assembly.
5, the bearing life is the manufacture, assembly, use is closely related to every aspect must be made in order to make the best functioning of the state of the bearing, thus extending the service life of cross roller bearings.
Through a combination of bearing failure and deterioration, performance status parameters to determine and predict the reliability and performance of the bearing, the site of the abnormal situation, causes and degree of risk identification and judgment to decide restoration and improvement of the integrated technology. Therefore, the bearing fault diagnosis technology is not a simple fault detection (or monitoring) technology, nor is it a simple point inspection instrumentation. Correctly, quickly and effectively signal acquisition, data processing, manual or automatic identification and judgment. In order to determine the scientific repair cycle, the mechanism should be based on various types of failure, fatigue, wear life tests and estimates necessary.
1, the shaft and the bearing housing tolerances choice and control: after pressure block has no bearing swivel sense of flexibility. If significant rotation is not flexible, then the shaft size is too large, and decreased tolerance. Such as bearings pressed into the hand after the obvious "imperfections" in a certain sense the steering shaft, it may be too round shaft or shaft tolerance is not good. A good shaft and bearing tolerances in the control room, so it should be controlled roundness.
2, the bearing assembly mode: Because bearings are precision products, such as improper assembly, easy to damage the channel bearings, resulting in bearing damage. Bearing in the assembly, there should be a special mold, can not beat, pushing the axial force can only be a small circle, the press force only when the circle. Assembly requires the use of pneumatic or hydraulic crimping die down when outside the country level, if the channel slope will lead cross roller bearing damage due to power, leaving the production of bearing guide ring.
3, the assembly to prevent foreign bodies: Bearing mounted rotor balancing is very susceptible to the iron homeostasis Before installing the bearings, so it is best to do balancing. Bearing in the conference room to put some oil or grease lubrication, but operators often difficult to control the amount of oil or grease the bearings if the plot to stay indoors, it's easy to rotate along the axis cross roller bearing. Bearing chamber is preferably not coated with oil or grease, such as non-coated control, without bearing to stay indoors.
4, paint rust prevention: paint rust is featured in a sealed motor, in the General Assembly multiple motors sounds good, but after a period of storage, the motor becomes a very unusual sound, remove the bearing severe rust. Many manufacturers will be considered before the cross roller bearing problems, now the main electrical plant has been aware of the problem of varnish. The main problem is that out of the insulating paint volatile acid at a certain temperature, humidity, corrosion and protection of metals, formation of corrosive substances, channels skf bearing cause corrosion damage. The only problem now is to choose a good varnish, dry air for some time after assembly.
5, the bearing life is the manufacture, assembly, use is closely related to every aspect must be made in order to make the best functioning of the state of the bearing, thus extending the service life of cross roller bearings.
Crossed roller bearings installed basic steps and use of environmental requirements
Bearing must be installed in a dry, clean environment conditions. Should be carefully checked before installation of shaft and housing mating surface, convex shoulder face, grooves and connecting surface processing quality. All surfaces must be carefully cleaned the mating connector and remove burrs, casting Ex unworked surface must be sand.
Bearing installation should be preceded with gasoline or kerosene to clean and dry before use, and to ensure good lubrication, bearings are generally lubricated with grease, oil lubrication can be. Lubricated with grease should be used free of impurities, oxidation, rust, and other superior performance extreme pressure grease. Grease filling is crossed roller bearings and bearing housing volume 30% -60%, not too much. With sealing structure of the double row tapered roller bearings and water pump bearing grease has been populated, the user can directly use, can no longer be cleaned.
Bearing installation must be on the circumference of the ring face exert equal pressure, push the ferrule may not be a direct hit with a hammer prime tool bearing face, so as not to damage the bearings. In the case of a small amount of interference, it can be pressed at room temperature with sleeve bearing ring face, beating with a hammer sleeve, the sleeve will be pressed into the ring balanced. If large quantities of installation, can be used hydraulic press. Press-fitting, should ensure that outer end face and the housing shoulder, inner end face and the shaft shoulder pressed, does not allow a gap.
First, bearing installation, you should use the appropriate measuring tool according to design drawings on technical requirements, check the shaft and housing bore and the relevant parts of the processing quality (such as dimensional accuracy, shape accuracy and surface roughness, etc.).
Second, the shaft and bearing assembly housing bore any bumps on the surface, burrs, rust or solid particles (such as debris, sand, mud), etc. exist, not only will the bearing installation difficulties and make the installation location is not correct, and solid particles as falling within a rolling start grinding effect, when the bearing rotates rubs or scratches will cross roller bearings work surface, so must be carefully checked before installation, if there is such defects should be corrected. For example, by removing burrs oil filed, raised bump marks, rust and polish with fine emery cloth, and if the cleaning of solid particles, dirt, etc..
Third, the mounting surface should be clean with gasoline, kerosene, toluene or xylene solution to clean clean and dry with a clean rag, then coated with a thin layer of oil, so make the installation more convenient.
Four, temporary installation, open bearings package, it will be immersed in the gasoline and other liquid gently rotated by hand, to ensure that cage, rolling element and raceway surface to be cleaned thoroughly cleansed encapsulated oil.
Five, cleaning a large cross roller bearings, the first with a temperature of 90 ~ 100 ℃ hot oil poured hot oil melted in the package, but the mouth does not drop crumbs seamless tool to dig the net all the old oil, then pour hot minutes then rinse with kerosene to oil, gasoline and then finally cleaned again. After clean washing, gloves should be worn thin the bearing on the work bench clean cloth or paper to dry.
Sixth, pay attention to this Act is not available with sealed bearings cleaned, sealed inside should remain as non-cleanable.
When a large amount of interference, can be oil bath heated by induction heating or crossed roller bearings way to install the heating temperature range is 80 ℃ -100 ℃, the maximum can not exceed 120 ℃. Meanwhile, the application of a nut or other appropriate methods tighten the bearing to prevent the bearing cooling after leaving the ring widthwise shrinkage gap between the shaft shoulder.
Finally, it should be installed bearing clearance adjustment. Clearance values should be based on the use of different conditions and the amount of interference with the size of specifically identified. Necessary, should be tested to determine. cross roller bearing and water pump bearing has been adjusted at the factory clearance, installation without further adjustment.
Bearing rotation test should be carried out after installation, first for rotating shaft or bearing housing, without exception, then in power for no-load, low speed, then gradually increase as the functioning of the rotation speed and load, and to detect noise, vibration and temperature , abnormal, should stop and check. Normal operation test before delivery.
Bearing installation should be preceded with gasoline or kerosene to clean and dry before use, and to ensure good lubrication, bearings are generally lubricated with grease, oil lubrication can be. Lubricated with grease should be used free of impurities, oxidation, rust, and other superior performance extreme pressure grease. Grease filling is crossed roller bearings and bearing housing volume 30% -60%, not too much. With sealing structure of the double row tapered roller bearings and water pump bearing grease has been populated, the user can directly use, can no longer be cleaned.
Bearing installation must be on the circumference of the ring face exert equal pressure, push the ferrule may not be a direct hit with a hammer prime tool bearing face, so as not to damage the bearings. In the case of a small amount of interference, it can be pressed at room temperature with sleeve bearing ring face, beating with a hammer sleeve, the sleeve will be pressed into the ring balanced. If large quantities of installation, can be used hydraulic press. Press-fitting, should ensure that outer end face and the housing shoulder, inner end face and the shaft shoulder pressed, does not allow a gap.
First, bearing installation, you should use the appropriate measuring tool according to design drawings on technical requirements, check the shaft and housing bore and the relevant parts of the processing quality (such as dimensional accuracy, shape accuracy and surface roughness, etc.).
Second, the shaft and bearing assembly housing bore any bumps on the surface, burrs, rust or solid particles (such as debris, sand, mud), etc. exist, not only will the bearing installation difficulties and make the installation location is not correct, and solid particles as falling within a rolling start grinding effect, when the bearing rotates rubs or scratches will cross roller bearings work surface, so must be carefully checked before installation, if there is such defects should be corrected. For example, by removing burrs oil filed, raised bump marks, rust and polish with fine emery cloth, and if the cleaning of solid particles, dirt, etc..
Third, the mounting surface should be clean with gasoline, kerosene, toluene or xylene solution to clean clean and dry with a clean rag, then coated with a thin layer of oil, so make the installation more convenient.
Four, temporary installation, open bearings package, it will be immersed in the gasoline and other liquid gently rotated by hand, to ensure that cage, rolling element and raceway surface to be cleaned thoroughly cleansed encapsulated oil.
Five, cleaning a large cross roller bearings, the first with a temperature of 90 ~ 100 ℃ hot oil poured hot oil melted in the package, but the mouth does not drop crumbs seamless tool to dig the net all the old oil, then pour hot minutes then rinse with kerosene to oil, gasoline and then finally cleaned again. After clean washing, gloves should be worn thin the bearing on the work bench clean cloth or paper to dry.
Sixth, pay attention to this Act is not available with sealed bearings cleaned, sealed inside should remain as non-cleanable.
When a large amount of interference, can be oil bath heated by induction heating or crossed roller bearings way to install the heating temperature range is 80 ℃ -100 ℃, the maximum can not exceed 120 ℃. Meanwhile, the application of a nut or other appropriate methods tighten the bearing to prevent the bearing cooling after leaving the ring widthwise shrinkage gap between the shaft shoulder.
Finally, it should be installed bearing clearance adjustment. Clearance values should be based on the use of different conditions and the amount of interference with the size of specifically identified. Necessary, should be tested to determine. cross roller bearing and water pump bearing has been adjusted at the factory clearance, installation without further adjustment.
Bearing rotation test should be carried out after installation, first for rotating shaft or bearing housing, without exception, then in power for no-load, low speed, then gradually increase as the functioning of the rotation speed and load, and to detect noise, vibration and temperature , abnormal, should stop and check. Normal operation test before delivery.
2013年8月9日星期五
Causing deep groove ball bearing temperature causes and countermeasures
Typically, if used correctly deep groove ball bearings, can be used to its maximum life so far. If not used correctly will have an unexpected injury prematurely. And fatigue life of this relatively early damage, malfunction or accident we call quality use limit. Multiple causes for installation, use, lubrication on the non-standard, or other foreign matter from outside intrusion.
Deep groove ball bearing damage on the state, such as: bearing rings, ribs card injury, mainly due to lack of lubricant, not suitable for oil discharge structure defects, the intrusion of foreign bodies, bearing misalignment, shaft deflections is too large, or both the above reasons.
Therefore, only the investigation bearing damage, injury is difficult to know the real reason. However, if you know the bearing using mechanical, conditions of use, bearing the surrounding structure, to understand the situation before and after the accident, combined with state of the bearing damage, and several reasons, we can prevent similar incidents from recurring.
deep groove ball bearing vibration of the bearing damage is very sensitive, such as peeling, dents, rust, cracks, wear, etc. will be in rolling bearing vibration measurement reflected, therefore, through the use of special bearing vibration measurements (frequency analyzer, etc.) can be measure the size of the vibration, can not be inferred by the frequency of abnormal circumstances. The measured values due to the conditions of use of rolling bearings or sensor installation location is different, so each machine needs prior to analysis and comparison of the measured values determined criteria.
Deep groove ball bearing temperature, generally room temperature outside of the bearing can be inferred, it can be measured directly using the hole bearing outer ring temperature, which is more accurately measured.
Typically, the temperature of rolling bearing operation began to rise slowly as 1-2 hours after reaching steady state. The normal temperature because of the machine bearing the heat capacity, heat capacity, speed and load are different. If lubrication, improper installation, the bearing temperatures will soar, there will be high, then you must stop running, check the disassembly repair. Conditional thermal sensor can be used at any time to monitor the bearing operating temperature, and to achieve the temperature exceeds a predetermined value or when the alarm automatically stops running to prevent burning shaft accidents.
Deep groove ball bearing damage on the state, such as: bearing rings, ribs card injury, mainly due to lack of lubricant, not suitable for oil discharge structure defects, the intrusion of foreign bodies, bearing misalignment, shaft deflections is too large, or both the above reasons.
Therefore, only the investigation bearing damage, injury is difficult to know the real reason. However, if you know the bearing using mechanical, conditions of use, bearing the surrounding structure, to understand the situation before and after the accident, combined with state of the bearing damage, and several reasons, we can prevent similar incidents from recurring.
deep groove ball bearing vibration of the bearing damage is very sensitive, such as peeling, dents, rust, cracks, wear, etc. will be in rolling bearing vibration measurement reflected, therefore, through the use of special bearing vibration measurements (frequency analyzer, etc.) can be measure the size of the vibration, can not be inferred by the frequency of abnormal circumstances. The measured values due to the conditions of use of rolling bearings or sensor installation location is different, so each machine needs prior to analysis and comparison of the measured values determined criteria.
Deep groove ball bearing temperature, generally room temperature outside of the bearing can be inferred, it can be measured directly using the hole bearing outer ring temperature, which is more accurately measured.
Typically, the temperature of rolling bearing operation began to rise slowly as 1-2 hours after reaching steady state. The normal temperature because of the machine bearing the heat capacity, heat capacity, speed and load are different. If lubrication, improper installation, the bearing temperatures will soar, there will be high, then you must stop running, check the disassembly repair. Conditional thermal sensor can be used at any time to monitor the bearing operating temperature, and to achieve the temperature exceeds a predetermined value or when the alarm automatically stops running to prevent burning shaft accidents.
Sealed deep groove ball bearings with grease on one side only
We use the process of deep groove ball bearing, bearing seals occasionally pry open the lid, this time we will find that while there is some bearing full of grease, while the other side there is no grease; while some bearing on both sides evenly fat distribution, especially the high price of the bearing, this is what causes it?
We know that the bearing during operation is the need to grease and rust, especially sealed deep groove ball bearings, grease the bearing can not be high-speed operation, will greatly shortened life expectancy. The bearing in the production process is a process up to a, the bearing inner ring and the balls, the cage is assembled, the first thing is to wash, rinse after the pressure side of the seal cover, and then flip over bearing, plus fat (Average plus the bearing interior volume is 30% ~ 35%), and then a cover.
Here we found, sealed deep groove ball bearing with one side in the production process are not added fat, grease applied to only one side only; if both sides, then add oil, bearing the manufacturing process, the more of a process, so the production efficiency will be reduced.
At this time someone will ask, why would some bearing grease on both sides of it? If the bearing grease seals on both sides, this one is the price is relatively high, and the other is used over the bearing. Why do you say? This is the high price of bearings are generally better quality, this is the result of deep groove ball bearing side full inspection, and that is to go through the rotating bearing test, after the rotation bearing grease on the inside of a uniform distribution; another is bearing After using, used, oil will certainly be evenly distributed.
So says the new deep groove ball bearings with grease on both sides of only one side while the other side is not normal, users do not worry, just take a few turns bearings, or turn a few minutes to get the machinery above, bearing grease on the inside of the uniform rotation , do not affect the use.
We know that the bearing during operation is the need to grease and rust, especially sealed deep groove ball bearings, grease the bearing can not be high-speed operation, will greatly shortened life expectancy. The bearing in the production process is a process up to a, the bearing inner ring and the balls, the cage is assembled, the first thing is to wash, rinse after the pressure side of the seal cover, and then flip over bearing, plus fat (Average plus the bearing interior volume is 30% ~ 35%), and then a cover.
Here we found, sealed deep groove ball bearing with one side in the production process are not added fat, grease applied to only one side only; if both sides, then add oil, bearing the manufacturing process, the more of a process, so the production efficiency will be reduced.
At this time someone will ask, why would some bearing grease on both sides of it? If the bearing grease seals on both sides, this one is the price is relatively high, and the other is used over the bearing. Why do you say? This is the high price of bearings are generally better quality, this is the result of deep groove ball bearing side full inspection, and that is to go through the rotating bearing test, after the rotation bearing grease on the inside of a uniform distribution; another is bearing After using, used, oil will certainly be evenly distributed.
So says the new deep groove ball bearings with grease on both sides of only one side while the other side is not normal, users do not worry, just take a few turns bearings, or turn a few minutes to get the machinery above, bearing grease on the inside of the uniform rotation , do not affect the use.
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