Needle Roller Bearing Research Articles

Mechanism analysis of burn-up failure for needle roller bearing at high-speed gear in manual transmission

Adequate lubrication conditions of needle roller bearings are crucial for the normal operation of transmission. Addressing the burn-up and adhesion failures of needle roller bearings during transmission bench trials, two rigid body rotation physical models were developed to analyze and model the lubrication effect on the inner and outer surfaces of needle roller bearing. Through theoretical analysis and lubrication simulation, it was found that under the critical condition of d/D=0.553, the centrifugal force F on the outer ring surface of the needle bearing was related to the density of lubricant, rotational speed, as well as the angle and size of oil hole, rather than the position of the oil holes; Moreover, the centrifugal force F on the needle roller bearing at input shaft was related to the speed of transmission gear and was also associated with the clearance size between needle roller and cage. Theoretical analysis, simulation, and experimental results have demonstrated that the lubrication performance of needle roller bearings during operation at lower rotary speed gears was inferior to that at higher speed gears, and the lubrication was also less effective when the cage clearance was narrower. Employing angled oil inlets (holes), appropriately enlarging the diameter of oil inlets (holes), and increasing the clearance width between needle roller and cage will contribute to the improvement of lubrication effect.

Transient Simulation Analysis of Needle Roller Bearing in Oil Jet Lubrication and Planetary Gearbox Lubrication Conditions Based on Computational Fluid Dynamics

The transient lubrication conditions of rolling bearings are different in gearboxes and bearing testers. It has been observed that samples of qualified rolling bearings tested in rolling bearing testers often fail and do not meet lifespan requirements when employed in other lubrication conditions. This may be caused by different factors affecting the bearing in testing and applying lubrication. Needle roller bearings were selected for this study to investigate the causes of this phenomenon in terms of lubrication. Based on the computational fluid dynamics (CFD) method, fluid domain models for the same type of rolling bearings with different lubrication conditions were established. The transient flow fields of rolling bearings with oil jet lubrication in a tester and splash lubrication in a planetary gearbox were simulated. The air–oil transient distribution of rolling bearings in two kinds of lubrication was analyzed. The results indicate that the rotational speed significantly affected the oil jet lubrication of the needle roller bearing. The average oil volume fraction rose by 0.2 with the increase in the bearing speed from 1200 r/min to 6000 r/min and by 0.06 with the increase in the oil jet velocity from 8 m/s to 16 m/s. The splash lubrication of the bearings in the planetary gearbox was directly related to the immersion depth of the rolling bearings in the initial position. Meanwhile, the splash lubrication of the bearings was also affected by other factors, including the initial layout of the planetary gears. The increase in speed from 1200 r/min to 6000 r/min made the average oil volume fraction of splash lubrication decrease by 4.4%. The average oil volume fraction of the bearings with splash lubrication was better than that with oil jet lubrication by an average of 41.9% when the bearing speed was in the low-speed stage, ranging from 1200 r/min to 3600 r/min. On the contrary, the bearings with oil jet lubrication were better than those with splash lubrication by an average of 31.8% when the bearing speed was in the high-speed stage, ranging from 4800 r/min to 6000 r/min.

Failure Analysis of a Needle Roller Bearing in a Megawatt Reciprocating Pump

In this paper, bearing failure was reported for a needle roller bearing used as intermediate support in a pinion shaft system. Severe deformation and wear were noticed on the working surface of the failed needle roller and around the window lintel of the bearing cage. The geometry, materials and hardness of the failed needle roller bearing were analyzed. Appearance detection, SEM and EDS analyses were carried out for clarifying the potential reasons of the needle roller bearing failure. The effect of radial displacement, Hertz contact stress and misalignment on the service life of the needle roller bearing were discussed. The excessive deformation and misalignment, resulting from the unbalanced loading and improper assembly, are the likely cause of the needle roller bearing failure.

Lubrication Condition Monitoring in EHD Line Contacts of Thrust Needle Roller Bearing Using the Electrical Impedance Method

In this study, we developed the electrical impedance method which simultaneously measures the thickness and breakdown ratio of oil films in elastohydrodynamic (EHD) line contacts within thrust needle roller bearings. Initially, we theoretically demonstrated that the oil film thickness and breakdown ratio can be simultaneously measured using the complex impedance that is produced when an AC voltage is applied to EHD line contacts. To verify the measurement accuracy of the electrical method, we monitored the oil film thickness of a thrust needle roller bearing and compared it with the theoretical value. The results revealed that the oil film thickness was thinner than the theoretical value immediately after starting the test, with the breakdown ratio being greater than 0 (indicating mixed lubrication); however, the breakdown ratio decreased over time, and the oil film thickness nearly matched the theoretical value one hour after starting the test, when it is believed that running-in wear is complete (i.e., breakdown ratio ≈ 0). Furthermore, following the test, after examining the race surface, we confirmed that running-in wear had indeed occurred. These results suggest that the developed method can monitor the lubrication conditions in EHD line contacts, such as those in thrust needle roller bearings, in detail.

Simulation Analysis of Skew Collision of Needle Roller Bearing Used in Precision Cycloid Reducer

In order to improve the service life of the needle roller bearing used in a precision cycloid reducer, and to reveal the skew and collision phenomenon of the needle roller bearing, based on the force analysis of the transmission mechanism of the cycloid reducer and considering the friction between the cycloid wheel, needle roller, cage, and crank shaft, the dynamic contact between the rolling bodies is simulated by the Hertz elastic contact, where the contact between the cage pocket hole and needle roller is equivalent to the spring and damping, and a nonlinear dynamic model of the needle roller bearing is established. The influence of different load and cage clearances on the deflection impact of the rotating needle roller bearing is calculated. The results show that the inclination of rollers is different under different pocket clearances, and the larger the pocket gap, the greater the fluctuation of the roller inclination angle; the action force of the crank shaft on the roller suppresses the deflection of the roller; the impact force of the roller on the cage has periodicity, which is consistent with the impact force of the crank shaft on the roller. The impact force of the cage is different under different loads, and the greater the load, the more rollers there are in the bearing area, the larger the impact force is, and the smaller the impact force of the rollers in the middle of the bearing zone is, compared with that of the rollers on the two sides; when the load is small, a pocket cage gap of 0.3 mm is selected, and when the load is heavy, a pocket cage gap of 0.2 mm is selected in order to make the bearing run more smoothly.

A novel test rig for the investigation of roller–cage impacts of a needle roller bearing

Collisions between a roller and its cage result in crack initiation and propagation, leading to the fracture of the cage bridge. The impact forces applied to a needle roller-bearing cage bridge can change the cage’s strain distribution, which is related to the relative speed of the roller and cage. In this work, a needle roller-bearing roller–cage impact test rig was built to quantify cage strain and investigate the effects of speed on roller–cage impact forces. On the cage bridge, three crack sizes were machined and put on the needle roller-bearing roller–cage impact test rig. The strain was measured by a strain gauge positioned on the cage. An encoder measured the shaft speed. The effects of impact speed and crack size on roller–cage impact force and cage deformation were investigated.

An optimisation analysis of external profile modification of outer raceway of a track needle roller bearing

The stress concentration phenomenon in the outer raceway will greatly influence the life and operational accuracy of track needle roller bearings (TNRBs). A reasonable contact surface profile of the outer raceway can reduce the stress concentration on its external profile. To reduce the stress concentration on the external profile of the outer raceway, a non-ideal Hertzian contact (NIHC) model for describing the interactions between the guide rail and outer raceway is presented by using the NIHC theory. The effects of the fully crowned profile (FCP), partially crowned profile with one curvature centre (PCPO), partially crowned profile with two curvature centres (PCPT), and logarithmic profile (LP) on the stress distribution between the guide rail and outer raceway are studied. Note that the stress concentration phenomenon of the PCPO case, PCPT case, and FCP can be produced. The stress distribution of LP case is more symmetrical and uniform than other cases. The stress distribution of the LP case is smaller than those of other cases. Therefore, the LP is more suitable for the outer raceway of the TNRB. Moreover, this method can be helpful for obtaining a reasonable external profile modification case of the outer raceway of the TNRBs.

An optimization analysis of external profile modification of outer raceway of a track needle roller bearing

An optimization analysis of external profile modification of outer raceway of a track needle roller bearing

Analysis of damage evolution and causative factors of outer raceway micromorphology of small needle roller bearings under impact load

Purpose This paper aims to investigate the damage evolution of bearing raceways under impact conditions from the perspective of three-dimensional (3D) surface morphology changes and to analyze the causal factors with the aid of simulation. Design/methodology/approach An experimental device containing an impact generating mechanism, a transmission mechanism and a torque load is designed for the experiments of impact damage to the outer raceway of a small needle roller bearing HK1208 without an inner ring. Microscopic images and height color maps of each experimental stage were obtained using a 3D laser measurement microscope. The characterization parameters of the surface 3D morphology were extracted and analyzed. Dynamics simulations of the impact condition were performed using the finite element method to investigate the variations and distribution characteristics of the roller forces on the raceway. Findings The changes in roughness and 3D micromorphology show that the surface flattening phenomenon caused by the flattening effect occurs before the surface of the bearing raceway is damaged. The result of dynamic simulations shows that the maximum load of the bearing under the impact state is obviously greater than that under a steady state, and the load distribution under the two conditions is significantly different. Originality/value This paper provides new ideas for analyzing the damage of bearings under impact conditions by analyzing the real 3D morphology of bearing raceways in combination with the finite element method.

Dynamics of a planetary needle roller bearing considering the waviness

A dynamic model of a planetary needle roller bearing (PNRB) considering the waviness is proposed. This model can formulate the PNRB dynamic motions under high centrifugal acceleration conditions, which are more complicated than those of shaft-fixed bearings. The waviness distributed on the surfaces of races and needle rollers can change the contact conditions between the needle rollers and races. In this study, the effect of the waviness on the roller-race contact forces, roller-cage impact forces, and the PNRB elements’ dynamics are discussed, which were not studied in the listed literature for the PNRB models. Moreover, a case of a PNRB in a single row planetary gear train is used to analyze the relationship between the needle roller-cage impact force and cage speed variation. The effect of the waviness on the vibration characteristics frequency of PNRB races are also studied.

PENGARUH PENAMBAHAN BEARING CAMSHAFT TERHADAP PERFORMA MESIN PADA MOTOR BENSIN 4 LANGKAH 150 CC

Abstract: This study aims to determine the effect of modification camshaft with addition needle roller bearing on the left and right side. After that compare the engine performance with the standard camshaft on the motorbike Suzuki Satria F150. The method used is an experiment. The test is carried out on the dyno test by paying attention to the value of engine speed, engine power, and the highest torque produced without limiting the gas valve opening. The results showed that after modification with the addition of a needle roller bearing the highest engine power was 18.70 HP and 12.23 N.m of torque at an engine speed of 10,888 RPM. With the addition of a needle roller bearing to the camshaft, the engine power was increased by 2.08 HP and the torque value was increased to 2 N.m Keywords: camshaft, needle roller bearing, engine performance

Experimental study on fault analysis of a needle roller bearing with wear evaluation

In this paper, an experimental setup has been developed to find out the wear of needle roller bearing. The signal processing method is used to extract the wear evaluation progress. Results are obtained in terms of the time series and FFT plots. The five events of the wear evaluation are analysed such as Misalignment fault, Indentation event, Smoothened dent, Defects and Damage growth state. The test is carried out for 480 hours of run of test bearing; the temperature varies from 68 to 78 °C. It is found that the needle roller bearing is damaged due to the high wear rate at the end of 480 hours of run of test bearing and the amplitude of acceleration in frequency domain is 32.51 m/s 2 at fifth event. It is also found that the amplitude of acceleration in frequency domain is more than the critical value of 30 m/s 2 . Therefore, the state at the end of 480 hours is the damage growth state of the needle roller bearing.

A Study on the Improvement of the Fatigue Life of Bearings by Ultrasonic Nanocrystal Surface Modification Technology

In this study, the effects of ultrasonic nanocrystal surface modification (UNSM) technology on the fatigue life of needle roller bearings were investigated. The fatigue life of the untreated and UNSM-treated needle roller bearings was evaluated using a roller fatigue tester at various contact stress levels, under oil lubrication conditions. It was found that the fatigue life of the UNSM-treated needle roller bearing was extended by approximately 34.3% in comparison with the untreated one. The results of the surface roughness and surface hardness of the needle roller bearings before and after UNSM technology were compared and discussed in order to understand the role of UNSM technology in improving fatigue life. It was found that the application of UNSM technology to the needle roller bearings can improve their fatigue life by reducing the friction coefficient and increasing the wear resistance, which may be attributed to the reduction in surface roughness from 0.50 µm to 0.15 µm and also the increase in surface hardness from 58 HRC to 62 HRC.

Experimental Evaluation on Vibration Analysis of a Needle Roller Bearing with Different Loads

The needle roller bearing is very important part of rotating machine thus the manufacturing of bearing is very essential with low vibration and high stability. In this paper, experimental work is done on oil lubricant of grade (ISO100) with different loads (20N, 40N, 60N, 80N, 100N and 120N) on needle roller bearings (202512). The signal processing technique is used to achieve the vibration analysis using parameter such as Displacement, Velocity, Acceleration and Frequency which obtain by vibration meter. It is the results that are drawn from the experimental work by signal processing technique are plotted in terms of Fast Fourier Transform (FFT).

Experimental Evaluation of Temperature Difference on Needle roller Bearing using Different Loads and Grades of oil Lubricant

Needle roller bearings are mostly used in most of the rotating machines because of their accuracy and proper working operation. The temperature difference of bearing is the most important factor for rotating machines which should be as low as possible. In this paper, the experimental work has been performed on needle roller bearing with different loads (20, 40, 60, 80 and 100 N) applied on it and with six lubricants of different viscosity grades (ISO 10, 32, 46, 68, 100 and 120). It is found that the temperature of test bearing is increased with increasing of applied load in every oil lubricant and the temperature difference is decreased from ISO 10 oil lubricant to ISO120 oil lubricant. It is also found that the speed of shaft maintained constant for the oil lubricants of ISO 10 to ISO100 but the speed of shaft is decreased using oil lubricant of ISO 120 due to high frictional force.

Improvement in Fatigue Life of Needle Roller Bearing

Improvement in Fatigue Life of Needle Roller Bearing

An investigation for the friction torque of a needle roller bearing with the roundness error

Needle roller bearings (NRBs) are key components in industrial machinery. The rotational accuracy and efficiency of the machinery are determined by the friction torques of their interior NRBs. This study proposes an analytical method for calculating the friction torque of a NRB without and with the roundness error. This model formulates the rolling friction torques produced by the elastic material hysteresis, slipping friction torques generated by differential slipping, viscous friction torques caused by the lubricating oil, slipping torques generated by the slipping between mating components, and centrifugal force of the needle roller. The friction torques of a healthy solid-grease-lubricated NRB calculated by Palmgren's, SKF's, Chiu and Myers's, and proposed methods are compared. The influences of the radial load, inner raceway velocity, and roundness error on the friction torque increment of an unhealthy solid-grease-lubricated NRB are analyzed by using the proposed method. Moreover, the results from Palmgrem's method, SKF's method, Chiu and Myers's method, proposed method, and Iqbal et al.’s experimental investigations are compared to validate the proposed method. It seems that this study can give a more accurate method for predicting the friction torque of the NRB with the roundness error compared to the previous empirical methods.

A procedure to determine the tangential true stress-strain behavior of pipes

Determining the tangential mechanical properties of a tube is essential for simulation of various manufacturing processes that involve the use of a tubular geometry. The aim of this study is to develop a procedure to determine the tangential true stress-strain behavior of pipes. For this purpose a modified ring test setup is proposed consisting of a ring specimen loaded with two separate D-blocks. Using a finite element model, an optimized ring specimen geometry is obtained. The optimized ring specimen exhibits uniform tangential distribution in the gauge region of the specimen and necking occurs consistently at the center of the gauge length. It is found that friction has a substantial effect on the mechanical response of the ring test for which two different setups to reduce friction are proposed. One using lubricated D-blocks (DB) and one using lubricated D-blocks with needle roller bearing (RB). Assisted by the FE model, the friction during the experiment is account for and a data analysis procedure to determine the tangential stress-strain curve of the pipe is proposed. It is found that the results using this procedure show very good agreement with previously published results.

Optimization of needle roller bearing design using novel hybrid methods

A long fatigue life is one of the most important criteria in the optimum design of needle roller bearings (NRBs). In the present work the dynamic capacity of the bearing is optimized. This non-linear optimization formulation has been solved using the artificial bee colony algorithm (ABCA), differential search algorithm (DSA), grid search method (GSM) and hybrid method (HM, a novel approach of combination of the ABCA/DSA and GSM). A total of four design variables corresponding to bearing geometry are considered, which include the roller diameter, roller length, pitch diameter and number of rollers. Apart from these three more constraint parameters have been optimized. The constraint violation study is carried out to prioritize the constraints. The sensitivity analysis is carried out to see the effect of tolerance on design variables on the dynamic capacity. The dynamic capacity of optimized bearings is found to have an upper hand from those specified in bearing catalogs.

Crown Drop Effects on the Needle Roller Bearing Life in Oscillatory

In this paper, the effects of chamfer dimension at the Lundbergs profile needle roller end and the grinding undercut of raceway on the pressure distribution, which are used in the oscillatory applications, are discussed. The frame of numerical method for the crown drop evaluation considered these two effects is presented, which makes it possible to profile the needle rollers axially until the longitudinal pressure distribution is neither any edge effects nor high-pressure concentration at the center part of contacts. And the crown drop designed by this method is larger than that by Lundbergs theory. The comparison results of accelerated rolling contact fatigue experiment show that the width of grinding undercut and radius of the chamfer must be considered in determining the crown drop of the needle rollers.