Thin slim ball bearing characteristics

slim ball bearing to achieve a very thin section bearing, but also to achieve a product miniaturization and lightweight. Diversity of products has expanded its range of purposes. In order to obtain a low friction bearing torque, high rigidity, good rotary precision, small diameter steel balls. Using a hollow shaft, ensuring lightweight space and wiring. Thin wall bearing rings were deep groove ball bearings, four point contact bearings, angular contact ball bearings. In different series are available in a variety of dollars more. Series depends on the cross-sectional size. Match ball and series. Deep groove ball bearings can support bi-directional axial load and radial load.

The establishment of flexible supporting thin angular contact bearing model

According to the thin wall of an aeroengine with angular contact ball bearing AC71907 as an example to analyze.

  Bearing parameters, outer diameter is 55mm, the outer ring raceway diameter is 50.586mm, the inner diameter is 35mm, the inner ring raceway diameter is 39.423mm, the ball diameter 5.556mm, the ball number 15, ( thin wall bearings )the initial contact angle of 25 deg..

  Between the bearing seat and the bearing outer ring is in interference fit, with the gap of m in 0-15um.

Modeling of thin-wall angular contact ball bearings

Because the need analysis of multiple change, load structure parameters on the performance of thin wall bearings, so in order to reduce repeated work analysis in modeling software ANSYS, design language in this paper using ANSYS finite element software provides the APDL parameter,

  the command to write parametric modeling of thin-wall angular contact ball bearing component of the flow, simplifies the process of repetition modeling,
and its optimal design and the two development laid a good.

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.

The solution of slewing ring bearing noise

   Slewing ring bearing noise common to have two kinds of dust acoustic sound and scars solution is as follows:
   (1) The control method of the dust acoustic
    Rotary branch within the dust and other foreign matter, non-periodic vibrations occur, the so-called dust acoustic, vibration and noise uncertain size, and with or without.Sound dust control methods: improving the cleaning method slewing ring / turntable bearing, the bearing before installation, shaft, housing bore all the rigorous cleaning and matching parts clean; remove foreign objects inside the lubricant; to improve angular contact ball bearing seals; avoid the use of impure material or a foreign body embedded plastic cage.
   (2)The control method scars sound
    If slewing ring rolling surface cracks, indentations or corrosion occurs as a rivet as periodic vibration and noise, the cycle may be fixed but most of the speed of a certain relationship, the scars on the channel will be continuous occurs, wounds hidden when on the ball, and this noise and there are some changes with the installation and lubrication conditions.
    Such noise control method: When installing not knock bearing, the bearing and the shaft bearing assembly before loading to prevent loading ramp when the bearing; when the stock to prevent shock and vibration to prevent bearing corrosion and transport; the use of high viscosity grease .
   (3) Noise and Countermeasures lubrication caused by factors Lubricant selection errors, lack of lubricant or the occurrence of aging sclerosis, can cause slewing ring / turntable bearing vibration and noise, and this noise is not necessarily the rule. In this case, only the choice of a suitable lubricant, lubricant adjust its volume, extend lubricant life and reasonably determine the replacement cycle.
   (4) the noise associated with the host and Countermeasures This noise is not simply caused by a handpiece bearing

, and thus to find a single reason from the bearing areas is ineffective to deal with a host full attention, to improve the performance of the host when necessary. The main narrative is now common in motor beeps and rack resonant sound.