slewing ring bearings Technical Requirements

Classification Summary Rolling classification of rolling bearings: Rolling bearing load bearing structure type classification  said contact angle is slewing bearing‍ divided into different radial bearings are mainly used to bear radial load Rolling nominal contact angle nominal contact angle divided into radial contact slewing ring bearings nominal contact angle heart to heart contact bearings bearing nominal contact angle greater than radial bearings thrust bearings are mainly used to bear axial load Rolling nominal 2002: Machine. 1. By Rolling structural type classification (1) can bear the load bearing their direction or precision spindle bearings‍ nominal contact angle, divided into: a) radial bearings ----- mainly used to bear radial load bearing, nominal contact angle from 0 to 45. Press nominal contact angle is different, is divided into: radial contact bearings ----- nominal contact angle is zero radial bearings: Radial angular contact bearings ----- nominal contact angle greater than radial bearings 0-45 of . 2) thrust bearing ----- mainly used for axial load bearing, the nominal contact angle greater than 45-90. Press nominal contact angle is divided into different: Axial contact bearings ----- nominal contact high precision bearings‍ angle of 90 thrust bearings: Axial angular contact bearings ----- nominal contact angle greater than 45 but less than 90 of the thrust bearing. 

slewing ring bearings The failure forms of rolling bearings

(a) fatigue spalling

Inside and outside the rolling bearing raceway and rolling body alternately to enter and exit the bearing area, these parts due to long time under alternating load, first from the contact surface following the largest alternating shear stress fatigue crack, and then high precision bearings‍ extend to the contacting surface produced punctate stripping in the surface layer, and gradually developed into large particles, called fatigue spalling.

(two) wear

The raceway and rolling body relative motion and dust caused by foreign body surface wear, lubrication will aggravate the wear, the slewing ring bearings‍ clearance increases, the surface roughness increased, decreased the SUNTHAI bearing rotation Taper roller bearings‍ accuracy, and thus reduce the motion accuracy of the machine, showed increasing vibration and noise.

(three).

Because the bearing inner raceway and rolling body contact on the surface of the micro convex or hard particles make contact surface uneven stress, in poor lubrication, high speed and heavy load conditions, due to the local friction heat caused by the contact surface of local deformation and friction welding, serious when may partially melted metal surface, the Flange Slewing Bearing‍ contact surface on the local friction force the welding point tear from the base.

(four) fracture

When the bearing load, vibration is too large, the defect position of inner and outer rings in the repeated impact roller, defects gradually expanded and fracture.

(five) corrosion

Water or acid, alkaline substances directly can cause invasive SUNTHAI bearing self aligning ball bearing‍ corrosion. When the SUNTHAI bearing internal shaft current through it, causing spark at the contact point raceway and rolling body to cause electrical erosion, formed on the surface of the uneven washboard.                        

slim ball bearing Wind power bearing production process

1, to control the forging temperature, not coarse grains;

2, to control the modulation quality process to ensure that quenched their core part of the organization to ensure its mechanical bearing‍ properties;

3, IF quenching surface hardened layer depth control;

4, to avoid surface micro cracks.                                                                                                                         Wind speed gearbox input shaft is generally 10-20 rev / min, due to the relatively low speed, [1] which is leading to the input shaft slim ball bearing‍ radial bearing‍ carrier support bearing oil film formation is often more difficult. The role of the film is when the bearing operation to separate two metal contact surfaces, avoid direct metal to metal contact occurs. We can introduce a parameter λ to characterize the Slewing drives‍ effect of lubricating the bearing (λ is defined as the film thickness and the roughness of the two contacting surfaces and the ratio).                               

thin section bearing Parts cleaning process

1 forging blank checks

2 Rough

3 Rough aging

4 fine cars

5 forming fine cars

Cross, three-row roller slewing Double Row Ball Slewing Bearing‍ bearing inner Special Process: To prevent cross, three-row thin section bearing inner heat treatment after deformation. When turning the pair must be processed, i.e., the raceway back-processing, cutting is not performed before the heat treatment, heat, cut molding.

6 heat treatment

Min raceway surface hardening (sometimes customer requirements can carburizing, nitriding, carbonitriding, etc.)

After quenching and tempering treatment

7 rolling, milling and Angular contact ball bearings‍ processing

8 during drilling according to customer requirements can be blue, phosphate, sulfide and other treatment

9 grinding coarse and fine grinding can be divided into two parts detection process 10.

10. demagnetization, cleaning, assembly, surface coated with anti-rust oil, grease filling, sealing nozzle, packaging (plastic film bag inner layer, an intermediate layer of kraft paper, plastic tape wrapped nylon outer layer).                   ‍

slewing ring bearings Wind power bearing

Wind power bearing lubrication analysis

Wind speed gearbox input shaft is generally 10-20 rev / min, due to the relatively low speed, [1] which is leading to the input shaft bearing carrier support high precision bearings‍ bearing oil film formation is often more difficult. The role of the film is when the bearing operation to slewing ring bearings two metal contact surfaces, avoid direct metal to metal contact occurs. We can introduce a parameter λ to characterize the effect of lubricating the bearing (λ is defined as the film thickness and the roughness of the two contacting surfaces and the ratio).

If λ is greater than 1, indicating Taper roller bearings‍ that the thickness of the metal film sufficient to separate the two surfaces, the lubricating effect is good; if λ is less than 1, then the thickness of the oil film can not completely separate the two metal surfaces, the lubricating effect is not ideal. In case of bad operation of the lubrication. Because wind power gearboxes are generally used ISOVG320 viscosity lubricant circulation, so if you find λ is less than 1, we generally can only be improved by reducing the lubricating effect of the roller bearing raceways and roughness.

In addition, the gear box design, the planet carrier bearing support end slewing bearing‍ to try to avoid bearing size is too small, the actual application analysis, we found that even life to meet the conditions, this design will lead to a small bearing line speed is very low, the film more can not be formed.

slim ball bearing Analysis of wind power bearing bearing area

In roller bearings generally operate only part withstand load, while the area where this part of the roller bearing area we call the bearing. The bearing load size, Crossed Roller Slewing Bearing‍ the size of the clearance operation will have an impact on bearing area. If the slim ball bearing area is too small, the roller in the actual operation is prone to slippage.

For the wind turbine gearbox, if the spindle is designed with double bearing support programs, then theoretically only torque is transmitted to the gear box. In this case, after a simple mechanical analysis, we find that the planet carrier supporting the bearing load is relatively small, so the load zone of the bearing is often relatively small, roller prone to slipping. In the design of wind turbine gearbox Slewing drives‍ carrier support bearings generally use two single row tapered roller bearings or cylindrical bearing two full programs.

We can properly preload tapered roller bearings or cylindrical roller bearings reduce clearance methods to improve the bearing area....                                                                                                                                                           ‍

thin section bearing The key technology of wind power bearing

Design and Analysis: Analog design experience is still the main study stress analysis and load spectrum is almost blank. Technical difficulties which are the requirements for spindle bearings trouble-free operation of 13 * 104h or more, and have more than 95 percent reliability; high precision bearings‍ gearbox bearings for high load capacity design a high failure rate and so on.

Materials: different parts of the bearing using different materials and heat treatment, such as increased yaw and pitch bearings 40CrMo steel at low temperature (ambient temperature -40 ℃ ∽-30 ℃, the thin section bearing‍ operating temperature of Taper roller bearings‍ about -20 ℃) ​​and other mechanical impact energy heat treatment method performance control surface induction hardening of the hardened layer depth, surface hardness, soft bandwidth and surface cracks; gearbox bearing equivalent foreign STF, HTF steel research and control its optimum content of residual austenite research; spindle bearing quality steel in the domestic vacuum degassing surviving in the case of a gap, using ESR carburizing steel ZG20Cr2Ni4A manufacturing.

Anti-corrosion and sealing.

Yaw and pitch bearing special clearance requirements.

Yaw and pitch bearing raceways precision spindle bearings‍ grinding.

Spindle bearings and gearbox bearings precision machining.

Transmission bearings maintain improved design frame.

Testing and so on.‍

slewing ring bearings The need to use grease understanding several indexes

When the selection of products of a kind of grease when needed, we should first make clear the grease the role: antifriction, silencing, protection, sealing etc.. Antifriction grease, should consider the range of high and low temperature, load and speed; the silencing of mobile crane bearing‍ grease, should consider the adhesion, temperature range, load and speed and so on; protective grease, consideration should be given to the metal, non protective compatibility with metal; slewing ring bearings grease, should consider the compatibility and seal material. Also should be selected according to the structure and environmental products grease lubricating parts of different working conditions, comprehensive up the following main indicators:

Working temperature: 1 by low Taper roller bearings‍ temperature limit the lowest temperature of lubricating parts should be higher than the grease, otherwise it will increase the resistance of the highest temperature should be below the temperature limit; grease, otherwise it will lose because of grease lubrication capacity loss; the highest applicable temperature grease should be below the drop point 20 ~ 30 ℃.

2 speed: lubricating parts of the operation speed is higher, the shear stress of the lubricating grease is bigger, and the high speed dynamic mechanical temperature to rise quickly, easy to make the lubricant thinning and erosion, so we should select the consistency grease bigger.

3: according to the load slewing ring bearings‍ load is the key to ensure the selection of grease lubrication, lubrication points should be used for heavy load of base oil with high viscosity, thickened grease agent content is high; if can bear heavy load and shock load, bearing‍ should choose high extreme pressure and anti grinding grease resistance, such as the grease containing molybdenum disulfide.                                                                                               4 conditions: environmental conditions refer to the work environment and the surrounding medium lubrication points, such as air humidity, dust and corrosive medium. In contact with water or damp environment condition, can choose the grease of water resistance. Such as calcium, lithium base; harsh conditions, should be used with grease and rust, but should not use sodium base grease water resistance is poor; in the lubrication points with strong chemical medium environment, should be chemical resistant selection of fluorine element grease; in the environment with more dust, grease containing graphite thick optional; to seal with special requirements, should use sodium base grease.

5 cost factors: in the selection of grease, but also consider ship loader bearing‍ the economic use, comprehensive analysis using this grease is extending the lubrication cycle, charging times, fat consumption, bearing failure rate and repair cost.

slewing ring bearings bearings

Wheel bearings can withstand a large axial load, radial load and overturning moment, comprehensive load, set support, large bearing rotation, transmission, fixed and other functions in one particular structure. Under normal circumstances, all with Series radial ball bearings‍ their own turntable bearing mounting holes, lubricants and seals, to meet the different needs of a variety of different conditions to work under the conditions of the various types of hosts; hand, turntable bearing itself has a compact structure, guide rotation convenient, easy to install and easy to maintain, etc., are widely used in material handling equipment, thin wall bearings‍ mining machines, construction machinery, port machinery, wind energy, medical equipment, radar and missile launchers and other large rotating equipment.                                                                                                                                                                     

slim ball bearing The structure and properties of angular contact ball bearing

(1) the angular contact ball bearing deep groove ball bearing basic similar shape, there is a ring with only a wall, the other side slope. Compared with the same series of deep groove ball bearings with inner diameter specifications, the difference lies in the cage structure and with the slim ball bearing‍ number of the steel ball a little more.

(2) in the deep groove ball bearing inner ring angular contact ball bearing with outer slope of the inner ring is completely general, such as the inner ring to the deep groove ball bearing 6204 generic row angular contact ball bearing 7204AC.

(3) the angular contact ball bearing retainer is real shape or stamped, no need of rivets.

(4) the limit speed angular contact ball bearing is higher than‍ that of deep groove ball bearing the same size.

(5) can bear radial load, Taper roller bearings‍ also can withstand a one-way axial load is larger, the contact angle is large ratio the bearing axial load and radial load is bigger.

(6) even bear radial load, also produce axial force, so the general angular contact ball bearings are used in pairs.

(7) the angular contact ball bearing Ding is, because of the effects of axial pre load after installation. Can eliminate bearing internal clearance, so relatively improve the rotation accuracy of R bearing. The application example in the machine tool spindle high precision, can make the radial and axial spindle runout minimum.

(8) two or more than two angular contact ball bearing group, can bear Excavator Slewing Bearing‍ double direction axial load, or increase the bearing capacity of the single direction axial load.

(9) through the pre load can obtain more rigid and maintain long-term rotation precision characteristics of bearing the original.                ‍

thin section bearing The failure forms of rolling bearings

(a) fatigue spalling

Inside and outside the rolling bearing raceway and rolling body alternately to enter and exit the bearing area, these parts due to long time under alternating load, first from the contact surface following the largest alternating shear stress fatigue crack, and then extend to the contacting surface Thin section bearings‍ produced punctate stripping in the surface layer, and gradually developed into large particles, called fatigue spalling.

(two) wear

The raceway and rolling body relative motion and dust caused by foreign body surface wear, lubrication will aggravate the wear, the bearing clearance increases, the surface roughness increased, decreased the SUNTHAI bearing rotation accuracy, and thus reduce the motion accuracy of the machine, showed increasing vibration and noise.

(three).

Because the bearing Full complement cylindrical roller bearings‍ inner raceway and rolling body contact on the surface of the micro convex or hard particles make contact surface uneven stress, in poor lubrication, high speed and heavy load conditions, due to the local friction heat caused by the contact surface of local deformation and friction welding, serious when may partially melted metal surface, the contact surface on the local friction force the welding point tear from the base.

(four) fracture

When the bearing load, vibration is too large, the defect position of inner and outer rings in the repeated impact roller, defects gradually expanded and fracture.

(five) corrosion

Water or acid, alkaline substances directly can cause angular contact bearing‍ invasive SUNTHAI bearing corrosion. When the SUNTHAI bearing internal shaft current through it, causing spark at the contact point raceway and rolling body to cause electrical erosion, formed on the surface of the uneven washboard.

slim ball bearing Some key points of maintenance and detection of bearing

1, in the use of the bearing process, regular cleaning is very important. How accurate cleaning bearings? First remove the bearings when the five, first with photography and other methods appearance record. In addition, to confirm that the remaining amount of lubricant and lubricant slim ball bearing‍ sampling, and then cleaning bearings.

2 bearing cleaning, rough cleaning and washing suspension, and metal frame use the bottom of the container placed on.

3, rough when washing, in oil use brush Su Qingrun grease or adhesions. If the oil migration shift bearing, note blend due to foreign bodies such as damage the rolling surface.

4, when sperm Taper roller bearings‍ washing, slowly in the oil migration shift bearing, be hard to stop.

Cleaning agent 5, usually used for neutral without water diesel oil or petroleum, based on demand and sometimes the use of temperature alkaline liquid. Regardless of the use of what kind of bearing‍ cleaning agents, are often filtered confrontation clean.

6, immediately after cleaning, coating rust preventive oil on the bearings or antirust grease.                                                   ‍

slewing ring bearings Note the plane bearing fault maintenance

A plane bearing fault feature showed a serious fault is less than a week time, large equipment, bigger, faster, the shorter time intervals. Therefore, the bearing fault diagnosis of actual, once found fault, its advanced function, should decisively determine the bearing fault, repaired as soon as possible.

Selection and control 1, slewing ring bearings‍ shaft and bearing chamber tolerance: press bearing plane bearing should be flexible rotation not block a sense of. If there is obviously the rotation is not flexible, indicates that the axial size is too large, the tolerance to cut. If the bearing onto the shaft by hand after turning has obvious "rustle" sense, the tolerances of the shaft may be too large or the roundness of the shaft is not good. So in the control of the shaft and housing tolerances to control the roundness, many domestic manufacturers only on tolerance control, no control of roundness.

2, the bearing assembly: because the bearings are  Other bearing  ‍precision products, such as improper assembly is easy to bearing raceway damage, cause damage to the bearing. Bearing assembly shall have the special mould, can not be beat, after pressing shaft when only small force, force pressure when only circle circle. The assembly by pneumatic or hydraulic press, the upper and lower mold to outside in the horizontal state, if tilt will cause the plane bearing raceway damage due to stress, and the bearing guide ring.

3, to prevent foreign bodies bearing assembly: easily mounted to the rotor dynamic balance when the dynamic balance of iron filings into bearing interior, so it is best to install bearing dynamic balancing. Some manufacturers in order to convenient assembly, the assembly of some oil or grease lubrication effect in the bearing chamber painted, but the operation is often difficult to control, if the oil or grease in the bearing chamber accumulates more, in the bearing rotates easily along the shaft into the plane bearing. The bearing chamber Triple row roller slewing bearing‍ is best not to oil or grease, such as non coated not to control may not be in the bearing chamber of accumulation.

4, rust prevention paint: paint rust is characterized by multiple sealed type motor, the motor voice in the assembly is very good, but in some time within the warehouse, the electrical noise change greatly, remove bearing with serious rust. Many manufacturers are considered to be before the bearing problem, through our advocacy, motor factory is now aware of the main insulation paint problems. This is mainly because the acidic material insulating paint volatile out of the formation of corrosive substances under certain temperature, humidity, the plane bearing groove corrosion cause bearing damage. The problem can only be good choice of insulating varnish, and after drying ventilation for a worm gear speed reducer‍ period of time after the assembly.

We should arouse our vigilance bearing assembly in the defects and other countries, failure is often very fast, very suddenly. That is after two hours, examples of this digital measurement of rotor shaft end.‍

‍

slewing ring bearings The characteristics of deep groove ball bearing

Deep groove ball bearing has the advantages of simple structure, compared with other types of easy to achieve high manufacturing accuracy, so easy to become series mass production, lower manufacturing costs, the use of very common. Select the radial internal clearance greater axial bearing slewing ring bearings‍ capacity, under purely radial force when the contact angle is zero. The action of axial force, contact angle greater than zero. General use of the stamping cage, car solid cage, sometimes also used nylon frame. Deep groove ball bearing except basic types, there are a variety of forms, such as: deep groove ball bearings with dustproof cover; deep groove ball bearings with rubber sealing ring; deep groove ball bearings with snap groove; deep groove ball bearing a large load capacity ball gap; Deep groove ball bearing‍ double deep groove ball bearings. But they all share the following characteristics:

Continuous groove type 1, each ring in the structure of deep groove ball bearing has a cross-section of approximately spherical perimeter 1/3 roller. It is mainly used to bear radial load, also can withstand the axial load;

2, in the bearing radial clearance increases, with the nature of angular contact ball bearing, the axial load bearing two directions alternating;

3, small friction, high speed; ‍

4, has the advantages of simple structure, low manufacturing worm gear speed reducer‍ cost, easy to manufacture high precision;

5, the general methods of stamping cage diameter greater than 200mm, the bearing or high-speed operation.       

slewing ring bearings diameter and rolling

according to the rolling bearing size classification according to the outer diameter of bearing size, divided into:

(1) the miniature bearing, nominal diameter slewing ring bearings‍ for bearing size below 26mm;

(2) small bearings -- nominal diameter size scale for 28-55mm bearing;

(3) small and medium-sized bearings, nominal diameter size scale for 60-115mm bearing;

(4) in large bearing - Nominal outside Crossed Roller Slewing Bearing‍ diameter size scale for 120-190mm bearing

(5) the large bearing - nominal diameter size scale for 200-430mm bearing;

(6) extra large type bearing, nominal diameter size for the bearing more than 440mm.                 ‍

thin section bearing high precision bearings:

high precision bearings: robot bearings and CNC machine tool YRT turntable bearing

(1) the robot bearing: thin-walled cross roller bearings, cross roller bearings, cylindrical roller in a V shaped groove 90 degrees

The rolling surface through the isolated blocks are arranged vertically, the

To cross roller bearings Thin section bearings‍ can bear radial load, axial load and torque load and multi direction load. The inner ring and the outer ring gauge

"Is small, thin form is more close to the limit of small

Type size, and has the advantages of high rigidity, and the precision can reach P5, P4, P2. (2) YRT rotary bearing, by a push

Centripetal force / seat, a thrust / radial shaft washer, a Flange Slewing Bearing‍ thrust washer, two needle roller and cage assemblies and a set of concentric

Cylindrical roller.

Seat ring and the shaft ring with a screw hole with a uniform installation. This type of bearing with high axial and radial load capacity‍

slim ball bearing components are respectively

 1.according to the number of rolling body, divided into:

1) single row bearings -- with a rolling body bearing;

2) double row bearings -- with two rows of rolling bodies bearing;

3) multi row bearing - slim ball bearing‍ with more than two rows of rolling bodies bearing, such as the three column, four row bearings.

2.according to their components are respectively, divided into:

1) respectively, has respectively bearing bearing components;

2) can not be separately - bearing in the final after supporting bearings, rings are not bearing any free respectively.

3.according to their structural shapes high precision bearings‍ (such as with or without filling slots, with or without inner, outer ring and ring shape, structure, retaining edge very

To non retaining frame) can also be divided into structural types.                                                        ‍