miniature ball bearings Regular maintenance and inspection of bearing

Play and its performance to maintain ball bearings ‍long-term to make the bearing fully, must cogent do regular maintenance (check). Double Row Ball Slewing Bearing‍ Through regular check for proper, do early detection of failure, to prevent accidents, is very important to improve the productivity and economy.

1, cleaning

Remove the bearings when the examination, using methods such as photographic appearance record. In addition, to confirm that the remaining amount of lubricant and lubricant sampling, and then cleaning bearings.

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

B, rough when washing, Full complement cylindrical roller bearings‍ use the brush in the removal of grease or oil adhesion. At this point if oil bearing, attention will be due to foreign bodies such as damage the rolling surface.

C, sperm washing, slowly rotating bearings in oil, be careful.

Cleaning agents are commonly used as neutral without water diesel or kerosene, sometimes using temperature as needed, such as lye. No matter what kind of cleaning agents, are often filtered clean.

After cleaning, immediately on the bearing coating antirust oil or antirust grease.

2, examination and judgment

In order to determine the bearing removed can re-use, to check on the accuracy of rotation accuracy, internal clearance, and the mating surfaces, raceway, cage and sealing ring.

About the examination results, can be thin wall bearings‍ judged by the bearing or bearing are used in.

Criteria based on the mechanical properties and the important degree and the inspection cycle and different. If the following injury, bearings shall not be re used, must be replaced.

1) bearing parts of the fault and defect.

2) the raceway surface rolling surface stripping.‍

flanged ball bearing

Show cross spiral line traces the emergence of such traces is mainly due to the bus straight wheel of existence, bump phenomenon, Double Row Ball Slewing Bearing‍ when in grinding, the grinding wheel and the workpiece is only part of the contact, when the workpiece or the grinding wheel reciprocating motion after several times, cross spiral line and the naked eye reproduced on the workpiece performance will be observed. The helix pitch and workpiece speed, rotational speed of workpiece size, but also with the wheel axis and the guide rail is not parallel to the working table.

(a) the main reason for the formation of the spiral line

1 grinding wheel dressing is bad, not chamfered corner, without the use of cooling liquid dressing;

Track 2 table guide Other bearing‍ lubrication oil too much, cause the work station floating;

3 machine tool accuracy is not good;

4 the grinding pressure and flanged ball bearing.

(two) with the formation of the spiral line

1.V guide not good rigidity, the grinding wheel edge offset, just contact with the work surface;

2 dressing noisy round table reversing speed is not stable, the precision is not high, the grinding wheel is a slightly less edge trimming;

The 3 workpiece itself poor rigidity;

4 wheel is broken too peeled off the sand and grinding of iron deposition in the grinding wheel on the surface, this should be trimmed worm gear speed reducer‍ grinding wheel with cooling water rinse or wash clean;

5 wheel dressing is not good, local projection etc..

Analysis of causes of bearing grinding traces generated.‍

high speed bearing Judgment bearing will use again

Judgment bearing will use again, to high speed ‍bearing damage degree, the machine performance, importance, operating conditions, crane bearing‍ such as checking cycle later decided. Check the results, if it is found that the bearing damage and abnormal situation, hurt a section to find out the reason, countermeasures. In addition, the inspection results, if there are some defects in it, the bearing can not be used, need to replace new bearing.

A. inner and outer ring, rolling body cage, in which any cracks and debris.

B. inner and outer ring, Single Row Ball Slewing Bearing‍ rolling body which any split.

C. raceway, rib, rolling card significantly hurt.

D. retainer wear or loosen rivets.

E. raceway surface, rolling rust and bruises.

F. surface of rolling, rolling a significant indentation and trace.

A creep of G. inner diameter of surface or outer diameter.

H. thermal slewing rings‍ discoloration.

I. grease sealed bearings seals and shields to serious damage.‍

miniature ball bearings Analysis of deep groove ball bearing quality

 Compared with sliding bearing, deep groove ball bearing and miniature ball‍ bearing, general conditions of deep groove ball bearing, the rolling Needle Roller Bearing‍ efficiency and hydrodynamic bearing lubricated bearings, but a mixed lubrication bearing to the high number of;

1, ability to withstand the impact load is poor;

2, the radial clearance is relatively small, angular contact radial bearings can be preloaded available pretightening force to eliminate the clearance, high running precision; high speed heavy load bearing life is low;

3, for the same size of Thin section bearings‍ the shaft diameter, bearing width smaller than the sliding bearing, the axial structure of machine is compact; vibration and noise;

4, most of the rolling bearing can be both radial and axial load, so the bearing assembly has the advantages of simple structure; the radial size than the sliding bearing;

5, the consumption of lubricant, which is convenient for sealing, easy maintenance;

6, do not need useful nonferrous linear ball bearing‍ metal;

7, a high degree of standardization, mass production, low cost;‍

flanged ball bearing matching precision bearing installation.

In order to improve the matching precision bearing installation, must use the measurement methods and tools do not make the flanged ball ‍bearing deformation, high precision bearings‍ precision measurement of bearing inner and outer circle with the surface size of the actual project, the measurement can be related to the inner and outer diameters of all be measured, and make a comprehensive analysis of the measured data, the according to precision bearings, matching with the shaft and hole of installation parts. The distribution of shaft and hole in the actual measurement of the corresponding size and geometry, temperature and measurement should be carried out in the bearing under the same.

To guarantee Taper roller bearings‍ the higher actual tie effect, the shaft and hole matched with a bearing surface, the roughness should be as small as possible.

In the above measurement, should be in the outer circle and bearing inner hole, and the corresponding surface of the shaft and the seat hole, on both sides near the assembly chamfer, respectively two groups of marker can show the maximum deviation direction, so that in the actual assembly, the match two party of maximum deviation of the same orientation so, in the assembly, the deviation can be partially offset.

The purpose of making two sets of directional signs, is the deviation compensation can be considered, even supported at both ends of each rotating accuracy slewing bearing‍ improved, and between the two bearing seat hole and the trunnion coaxiality error on both ends are partially eliminated. The mating surface to surface strengthening measures, such as sandblasting, precision plunger diameter slightly larger plug a hole, are beneficial to improve matching precision. 

high speed bearing The sequential step bearing finishin

Bearing order superfinishing can generally be divided into three steps: cutting, cutting, semi finishing machining.

The first step: Bearing cutting

Convex peak surface conical bearing‍ contact surface and rough rolling stone, due to a smaller contact area, a force per unit area is larger, in certain pressure, stone first by bearing workpiece "anti cutting" role, the stone surface of abrasive loss and fragmentation, showing some new sharp grinding grain and edge. At the same time, surface asperity bearing workpiece by fast cutting, the cutting and anti cutting to remove the bearing surface of the workpiece and the grinding affected layer of convex peak. This stage is called the cutting stage, at this stage most of removed metal allowance.

The second mobile crane bearing‍ step: cutting bearing

As the process continues, bearing the workpiece surface has been polished. At this time, a contact with the workpiece surface area increased, the unit area pressure decreases, the cutting depth decreases, the cutting ability is abate. At the same time, hole stone surface is blocked, stone in the half cutting state. This stage is called semi cutting stage bearing finishing, half cutting stage cutting workpiece surface bearing traces of shallow, and the emergence of reali slim bearings‍ dark luster.

The third step: the finishing stage

This is the last step in ultra precision machining of bearing. With the workpiece surface to be gradually removed, the contact area of stone and workpiece surface is further increased, and, stone and bearing surface gradually by the lubricating oil film isolation, the force per unit area is very small, the cutting effect decreases, then automatically stop cutting. At this stage we Series super thin section bearings‍ call the finishing stage. The whole stage light surface workpiece without cutting mark, SKF bearing appears bright finished luster.

miniature ball bearings comprehensive up the following main indicators

Working temperature: 1 by low 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, wind power bearing‍ 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 miniature ball ‍bearing load is the key to ensure the selection of grease lubrication, lubrication points taper roller bearing‍ 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, 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 Angular contact ball bearings‍ 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 the economic use, comprehensive analysis using this grease is extending the lubrication cycle, charging times, self aligning bearing‍ fat consumption, bearing failure rate and repair cost.