Improvement of Deep Groove Ball Bearing’s Performance Using a Bionic Textured Inner Race

Vibration signal of a defective bearing carries fault related information. The aim of this paper is to develop a signal processing methodology that identifies the presence of defect from bearing vibration signal subjected high background noise. A simulated vibration signal considering inner race defect in a deep groove ball bearing with low signal to noise ratio has been generated and investigated. A technique involving CWT of vibration signal and post-processing though FFT has been adopted to analyze the signal. Results show that proposed methodology can yield the presence of inner race defect prominently from a noisy vibration signal.

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The Vibrations of Radial Ball Bearings

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/pime_proc_1985_199_113_02 ◽

1985 ◽

Vol 199 (3) ◽

pp. 181-193 ◽

Cited By ~ 111

Author(s):

H Rahnejat ◽

R Gohar

Keyword(s):

Theoretical Analysis ◽

Small Amplitude ◽

Ball Bearings ◽

Surface Waviness ◽

Harmonic Frequency ◽

Linear Elastic ◽

Gravity Load ◽

Deep Groove ◽

Oil Films ◽

Inner Race

This paper presents a theoretical analysis of the vibration response of a rotating rigid shaft supported by two radial deep-groove lubricated ball bearings. The bearings and their oil films are approximated to a set of non-linear elastic springs and dampers rotating relative to the shaft when it is subjected to a rotating unbalance or inner race surface waviness. Under gravity load, the shaft's initial vibration is damped down to a limit cycle operating at a quasi-simple harmonic frequency of small amplitude. Rotating unbalance and surface features introduce further significant frequencies which influence the output response.

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A Study of Residual Stress Induced During Rolling

Journal of Lubrication Technology ◽

10.1115/1.3554921 ◽

1969 ◽

Vol 91 (2) ◽

pp. 314-318 ◽

Cited By ~ 31

Author(s):

E. V. Zaretsky ◽

R. J. Parker ◽

W. J. Anderson

Keyword(s):

Residual Stress ◽

Residual Stresses ◽

Ball Bearings ◽

Radial Load ◽

Stress Measurements ◽

Deep Groove ◽

Track Surface ◽

Inner Race ◽

Compressive Residual Stresses ◽

Made In

Subsurface residual stress measurements were made on SAE 52100 steel inner races from 207-size deep-groove ball bearings in which ΔH (ball hardness minus race hardness) ranged from −1.1 to 3.5 points Rockwell C. These bearings had been run at an inner-race speed of 2750 rpm and a radial load of 1320 lb producing maximum Hertz stresses of 352,000 and 336,000 psi at the inner and outer races, respectively. The residual stress measurements were made in a circumferential direction at various depths below the inner-race running track surface for a total of 19 of these bearings that had been run for nominally 200, 600 and 1600 hr. The measurements indicated that the maximum compressive residual stresses occur in approximately the same ΔH range for which the maximum fatigue lives were observed. Additionally, no relation between running time and residual stress could be determined from these measurements.

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An exploration of frictional and vibrational behaviors of textured deep groove ball bearing in the vicinity of requisite minimum load

Friction ◽

10.1007/s40544-021-0495-3 ◽

2021 ◽

Author(s):

K. E. Ch. Vidyasagar ◽

R. K. Pandey ◽

Dinesh Kalyanasundaram

Keyword(s):

Ball Bearing ◽

Load Capacity ◽

Substantial Reduction ◽

Frictional Torque ◽

Ball Bearings ◽

Nanosecond Pulsed Laser ◽

Deep Groove ◽

Deep Groove Ball Bearing ◽

Micro Dimples ◽

Inner Race

AbstractIn case of lightly loaded radial ball bearings, failure mechanisms other than fatigue such as smearing of raceways due to increased frictional torque and vibrations often prevail. Hence, attempts have been made herein for reducing the frictional torque and minimizing the vibrations of a radial deep groove ball bearing employing surface textures at the inner race. Nanosecond pulsed laser was used to create texture (involving micro-dimples having different dimple area density) on the inner race of test bearings. Using an in-house developed test rig, frictional torque and vibrational parameters were measured at different speeds and light loads (i.e. in vicinity of 0.01C, where C is dynamic load capacity of radial ball bearing). Significant reduction in frictional torque and overall vibrations were found in the presence of micro-dimples on inner race at light loads irrespective of operating speeds. Even without satisfying the minimum load needed criteria for the satisfactory operation, substantial reduction in smearing marks was found on the races of textured ball bearings in comparison to conventional cases.

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Lightweight Cement Conglomerates Based on End-of-Life Tire Rubber: Effect of the Grain Size, Dosage and Addition of Perlite on the Physical and Mechanical Properties

Materials ◽

10.3390/ma14010225 ◽

2021 ◽

Vol 14 (1) ◽

pp. 225

Author(s):

Andrea Petrella ◽

Michele Notarnicola

Keyword(s):

Grain Size ◽

End Of Life ◽

Compression Tests ◽

Tire Rubber ◽

Impact Compression ◽

Weight Percentage ◽

Deep Groove ◽

Mechanical Strengths ◽

The Impact ◽

Thermal Conductivities

Lightweight cement mortars containing end-of-life tire rubber (TR) as aggregate were prepared and characterized by rheological, thermal, mechanical, microstructural, and wetting tests. The mixtures were obtained after total replacement of the conventional sand aggregate with untreated TR with different grain sizes (0–2 mm and 2–4 mm) and distributions (25%, 32%, and 40% by weight). The mortars showed lower thermal conductivities (≈90%) with respect to the sand reference due to the differences in the conductivities of the two phases associated with the low density of the aggregates and, to a minor extent, to the lack of adhesion of tire to the cement paste (evidenced by microstructural detection). In this respect, a decrease of the thermal conductivities was observed with the increase of the TR weight percentage together with a decrease of fluidity of the fresh mixture and a decrease of the mechanical strengths. The addition of expanded perlite (P, 0–1 mm grain size) to the mixture allowed us to obtain mortars with an improvement of the mechanical strengths and negligible modification of the thermal properties. Moreover, in this case, a decrease of the thermal conductivities was observed with the increase of the P/TR dosage together with a decrease of fluidity and of the mechanical strengths. TR mortars showed discrete cracks after failure without separation of the two parts of the specimens, and similar results were observed in the case of the perlite/TR samples thanks to the rubber particles bridging the crack faces. The super-elastic properties of the specimens were also observed in the impact compression tests in which the best performances of the tire and P/TR composites were evidenced by a deep groove before complete failure. Moreover, these mortars showed very low water penetration through the surface and also through the bulk of the samples thanks to the hydrophobic nature of the end-of-life aggregate, which makes these environmentally sustainable materials suitable for indoor and outdoor elements.

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Impact-Rubbing Dynamic Behavior of Magnetic-Liquid Double Suspension Bearing under Different Protective Bearing Forms

Processes ◽

10.3390/pr9071105 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1105

Author(s):

Jianhua Zhao ◽

Lanchun Xing ◽

Sheng Li ◽

Weidong Yan ◽

Dianrong Gao ◽

...

Keyword(s):

Dynamic Behavior ◽

Ball Bearing ◽

Magnetic Liquid ◽

Electromagnetic System ◽

Fixed Ring ◽

Deep Groove ◽

Deep Groove Ball Bearing ◽

Protection Devices ◽

Hydrostatic System ◽

The Impact

The magnetic-liquid double suspension bearing (MLDSB) is a new type of suspension bearing, with electromagnetic suspension as the main part and hydrostatic supports as the auxiliary part. It can greatly improve the bearing capacity and stiffness of rotor-bearing systems and is suitable for a medium speed, heavy load, and frequent starting occasions. Compared with the active electromagnetic bearing system, the traditional protective bearing device is replaced by the hydrostatic system in MLDSB, and the impact-rubbing phenomenon can be restrained and buffered. Thus, the probability and degree of friction and wear between the rotor and the magnetic pole are reduced drastically when the electromagnetic system fails. In order to explore the difference in the dynamic behavior law of the impact-rubbing phenomenon between the traditional protection device and hydrostatic system, the dynamic equations of the rotor impact-rubbing in three kinds of protection devices (fixed ring/deep groove ball bearing/hydrostatic system) under electromagnetic failure mode are established, and the axial trajectory and motion law of the rotor are numerically simulated. Finally, the dynamic behavior characteristics of the rotor are compared and analyzed. The results show that: Among the three kinds of protection devices (fixed ring/deep groove ball bearing/hydrostatic system), the hydrostatic system has the least influence on bouncing time, impact-rubbing force, and impact-rubbing degree, and the maximum impact-rubbing force of MLDSB is greatly reduced. Therefore, the protective bear is not required to be installed in the MLDSB. This study provides the basis for the theory of the “gap impact-rubbing” of MLDSB under electromagnetic failure, and helps to identify electromagnetic faults.

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Dynamic modeling and quantitative diagnosis for dual-impulse behavior of rolling element bearing with a spall on inner race

Mechanical Systems and Signal Processing ◽

10.1016/j.ymssp.2021.107711 ◽

2021 ◽

Vol 158 ◽

pp. 107711

Author(s):

Maolin Luo ◽

Yu Guo ◽

Hugo Andre ◽

Xing Wu ◽

Jing Na

Keyword(s):

Dynamic Modeling ◽

Rolling Element Bearing ◽

Quantitative Diagnosis ◽

Rolling Element ◽

Element Bearing ◽

Inner Race

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Coupled Thermo-Mechanical FEA of Three-Roll Cross Rolling Process for Rings with Small-Hole and Deep Groove

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.560-561.846 ◽

2012 ◽

Vol 560-561 ◽

pp. 846-852 ◽

Cited By ~ 3

Author(s):

Qi Ma ◽

Lin Hua ◽

Dong Sheng Qian

Keyword(s):

Rolling Process ◽

Small Hole ◽

Fe Model ◽

Forming Process ◽

Software Environment ◽

Cross Rolling ◽

Design And Optimization ◽

Forming Technology ◽

Deep Groove ◽

Plastic Forming

Ring parts with small-hole and deep groove such as duplicate gear and double-side flange, are widely used in various engineering machineries. Three-roll cross rolling (TRCR) is a new advanced plastic forming technology for the processing of rings with small-hole and deep groove. In this paper, a 3D coupled thermo-mechanical FE model for TRCR of ring with small-hole and deep groove is established under ABAQUS software environment. By simulation and analysis, the evolution and distribution laws of strain and temperature in the forming process are revealed, and the effects of the key process parameters on the deformation uniformity are explored. The results provide valuable guideline for the technological parameter design and optimization.

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Endurance and Failure Characteristic of Main-Shaft Jet Engine Bearing at 3 × 106 DN

Journal of Lubrication Technology ◽

10.1115/1.3452940 ◽

1976 ◽

Vol 98 (4) ◽

pp. 580-585 ◽

Cited By ~ 23

Author(s):

E. N. Bamberger ◽

E. V. Zaretsky ◽

H. Signer

Keyword(s):

Ball Bearings ◽

Main Shaft ◽

Test Results ◽

Jet Engine ◽

Material Life ◽

Thrust Load ◽

Inner Race ◽

Continuous Running ◽

Life Factor ◽

Engine Bearing

Groups of thirty 120-mm bore angular-contact ball bearings were endurance tested at a speed of 12 000 and 25 000 rpm (1.44 × 106 and 3.0 × 106 DN) and a thrust load of 66 721 N (5000 lb). The bearings were manufactured from a single heat of VIM-VAR AISI M-50 steel. At 1.44 × 106 and 3.0 × 106 DN, 84 483 and 74 800 bearing test hours were accumulated, respectively. Test results were compared with similar bearings made from CVM AISI M-50 steel run under the same conditions. Bearing lives at speeds of 3 × 106 DN with the VIM-VAR AISI M-50 steel were nearly equivalent to those obtained at lower speeds. A combined processing and material life factor of 44 was found for VIM-VAR AISI M-50 steel. Continuous running after a spall has occurred at 3.0 × 106 DN can result in a destructive fracture of the bearing inner race.

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Note on the Transformation of Ciliated into Stratified Squamous Epithelium as a result of the Application of Friction

Proceedings of the Royal Society of Edinburgh ◽

10.1017/s0370164600006192 ◽

1890 ◽

Vol 16 ◽

pp. 119-120 ◽

Cited By ~ 4

Author(s):

John Berry Haycraft ◽

E. W. Carlier

Keyword(s):

Mucous Membrane ◽

Squamous Epithelium ◽

The Other ◽

Ciliated Epithelium ◽

Deep Groove ◽

Stratified Squamous Epithelium ◽

Trachealis Muscle

(Abstract.)In man, in the rabbit, and some other animals the trachea is built up of a series of cartilaginous rings incomplete behind; the rings being completed in this position by the trachealis muscle.The mucous membrane forms a smooth cylindrical lining for the whole tube, and is covered by a ciliated epithelium.In the cat and dog the cartilage rings completely encircle the trachea, and overlap posteriorly, and the trachealis muscle, which is well developed, is placed outside the cartilage, and has a powerful action in varying the diameter of the tube.When this muscle contracts the overlapping ends of the cartilage ride one upon another, and the projecting ends form a vertical ridge down the inside of the trachea, which can be readily seen on slitting the organ open. This ridge is separated by a deep groove from the other end of the plate.

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