The reason of aligning ball bearing failure analysis

aligning ball spherical ball bearings cause of failure is often multifactorial, all design and
manufacturing process and the impact of factors related to failure of the bearing, it is not easy to judge the analysis. Under normal circumstances, in general, can be considered and analyzed both from the use of factors and internal factors.
Use the adjustment factor mainly refers to the installation, use and maintenance, repair and other maintenance meets the technical requirements. Installation conditions is one of the primary factors in the use of the factors bearing is often caused due to improper installation package bearing the stress state changes between the various parts, aligning ball bearing in a normal state of operation and early failure. According to the spherical plain bearings installation, use, maintenance, maintenance of the technical requirements for operation of
the bearing to withstand load, speed, temperature, vibration, noise and lubrication condition monitoring and inspection, abnormal immediately find reasons to adjust to return to normal. In addition, the quality of the grease and the surrounding medium, and the atmosphere is also important for analysis testing.
Internal factors mainly refers to the design, manufacturing process and material quality three factors determine the quality of the bearing.
First, along with a reasonable structure design has advanced, will have a longer bearing life. Manufacture of bearings generally through forging, heat treatment, turning, grinding and assembly of multi-channel processing. The reasonableness of the processing technology, advanced, will also affect the stability of the bearing life. Which affect the quality of the finished product bearing heat treatment and grinding processes, tend to have a more direct relationship with the failure of the bearing. Recent studies on the bearing surface metamorphic layer show that the grinding process is closely related to the bearing surface
quality.
Metallurgical quality aligning ball four point contact ball slewing bearing material was the main factor affecting the early Rolling failure. As metallurgical techniques (such as bearing steel vacuum degassing, etc.) advances, improved quality of raw materials. Raw material quality factors in bearing failure analysis in the proportion has decreased significantly, but it is still one of the main factors bearing failure. The adequacy of the selection is still bearing failure analysis of factors must be considered.
The main task of aligning ball bearing failure analysis is based on a lot of background material, analysis of data and failure modes, failure to identify the main factors causing the bearing to make targeted improvements to extend bearing service period, to avoid bearing occurrence of unexpected early failure.

Wheel bearing applications in various fields of anatomy

Wheel bearings, slewing ring, also known as, is a way to withstand the large axial load, radial load and overturning moment of large bearings. Wheel bearings generally come with mounting holes, internal gear or external gear, lubrication holes and seals, which enables a host compact design guide reliable, easy maintenance.Have toothed wheel bearings, the outer and inner tooth tooth four-point contact ball bearings, double row angular contact ball ferris wheel bearing, crossed cylindrical roller bearings, tapered roller bearings and cross three-row cylindrical roller bearings, and other kind of structure type. Where the four-point contact ball bearings with high static load capacity; Cross cylindrical roller bearings with high dynamic load capacity; cross-tapered roller bearings through preloaded make bearings with a larger supporting rigidity and high
rotation accuracy.
Wheel handpiece bearing are widely used in lifting the machinery, mining machinery, construction machinery, port machinery, shipbuilding, machinery and mechanical precision radar and missile launchers and other large rotating equipment.
Wheel bearings used in various fields.
1. Wind Turbine
The connecting portion of the tower with a yaw bearing is mounted in the cockpit, the pitch bearing is installed with the hub at the root portion of each blade is connected. Each wind generator with a yaw bearing and three pitch bearing. Yaw, pitch bearing ring material selection 42CrMo, heat treatment with the overall quenching, raceway surface hardening. Yaw, pitch bearing force the situation is complex, and to withstand shock and vibration is relatively large, and therefore, require both bearings to withstand the impact, but also bear a greater load. Wind turbines host life requirements of 20 years, a larger bearing installation costs, thus requiring yaw, pitch bearing life have reached 20 years. The matrix hardness of the bearing rings 240-280HB, able to withstand impact without the occurrence of plastic deformation, while the raceway surface quenching hardness 55-
62HRC, contact fatigue life can be increased, so as to ensure long bearing life
requirements.
2. Ship Cranes
Ship Cranes general use double Reducing ball, four-point contact ball bearing turntable Tri-row roller tooth structure, depending on the load carrying capacity, three-row roller wheel bearings typically used for heavy-duty cranes, four-point contact ball slewing and Reducing double ball bearing turntable for light cranes.
Since the crane at -20 ° C - +45 ° C under work environment, high class material bearing on the mechanical performance requirements.
3. offshore crane
Depending on the load capacity requirements, offshore crane usually using four-point contact ball slewing and three-row roller gear wheel bearings.
Application in offshore crane turntable bearing with special material requirements, the mechanical properties of the material to be able to guarantee the safety factor under extreme load, forging sample Charpy impact test to reach the average of 42J @ -20 ° C or 27J @ -40 ° C. Bearing Classification Society certification to be finished.
4. harbor mobile cranes
4 meters of harbor cranes usually use internal or external gear teeth diameter three-row roller slewing bearings to withstand high overturning moment.
5. Stacker Reclaimer
Reclaimer with column wheel bearings usually ball joint, three-row roller and cross-roller type, most ultra-three meters in diameter. Due to poor working conditions, dusty, these bearings have a high load capacity, long life, good sealing performance characteristics.
6. Ferris Wheel
For four-point contact ball bearing turntable Ferris wheel on the outside diameter of 4100mm, thickness 85mm
7. unloader
Unloader wheel bearings with external teeth usually three-row roller structure, about 4 meters in diameter.
8. Crane
Tower crane used wheel bearings usually small size four-point contact ball bearing turntable or dual volleyball dial diameter of not more than two meters.
9. The radar antenna
Shortwave antenna generally with three-row roller bearing turntable sub-structure, the rotation is slow.
10. TBM
Shield machine with turntable bearing diameters from 2.5 m to 6 m range, some larger diameter, these bearings working under very harsh conditions, bearing carrying a large load, corrosion resistance, short life.
11. ladle turret
Ladle turret slewing bearing usually with three-row roller structure, due to work under harsh conditions with dust and high temperature conditions, and on the holder, grease and seals have very high demands.
12. Construction Machinery
Wheel ring bearing typically used in construction machinery in a small four-point contact

ball bearing turntable, a diameter of not more than two meters.

The inner ring split type cross roller bearings use characteristics

1 tolerance: general bearing, inner ring rotation relative to the outer ring, with tighter.The outer loose. The main reason is the outer ring plays a supporting role, no rotational force big.

(micro, outer ring relatively peristalsis, but not much) RE type bearing is just the opposite, namely two ring bearing force just the opposite. So, tolerance to the contrary. Active rotation

The ring fit will be relatively tight.

2 clearance: clearance basically selection and temperature and tolerance related. If only the outer ring of bearing tolerances for the elastic case, then influence the changes before and after not Is particularly high (but certainly, the precision can not be ignored), generally can be considered and the general bearing, because tolerance variations. As for the temperature, which completely and a revolving around it doesn't matter, mainly to see the external heat source. So there is no too much change. In a word, cross roller bearing clearance basically can choose to speed, temperature standard.

3 lubrication, should pay attention to, if the seal bearing, please do not use the dust cover, bearing will spill. To choose the rubber seal. If open bearing, a general note,then

Lubrication time interval to adjust for the past half. bearing with grease lubrication and lubrication of the sealing rubber ring double, ensure the lubrication effect of high precision bearings.‍