Browse Topic: Bearings

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Mechanical complex assembly2025-28-0262To be published on 11/06/2025
Title: Two weldments assembled using four or more bolts. Abstract consists of study on Two weldments assembled using four or more bolts. Assembly preload stress effect on weld area of subassembly. There are three different assembly fits. 1. Clearance fit. 2. Interference fit. 3.Transition fit. Preload stress on weldments generated are different for three different fits of assemblies. In industry interference & Transition fits required special tooling to assemble parts together. Ergonomically it is not practice using interference fit. In case of interference fit: We need to assemble part with applying hammer. In that case when apply torques on bolted joint. Preloads on assembly is adequate. This joint is good joint. Clearance fit: Preloads Stresses on joints will be higher & severe based on size of gap in between joining surfaces. These types of stresses will cause crack generation on welded are of sub-assembly. Further in cyclic load crack propagates. Clearnce fit and Shims: We can
Kazi, Mohseen Vahab, Gandhi, Mitesh
Advanced 3D Simulations of a Four-Stroke High-Performance Engine Valvetrain for the Analysis of the Mechanical Stresses and Energy Losses2025-32-0010To be published on 11/03/2025
Enhancing the performance of naturally aspirated 4-stroke engines relies heavily on improving trapping efficiency, increasing maximum engine speed, and reducing friction losses. In this regard, the valvetrain plays a critical role. Achieving high volumetric efficiency at higher engine speeds necessitates very steep valve opening and closing ramps, making this aspect pivotal in the design process. At high engine speeds, significant dynamic phenomena arise, including valve float, during the lift phase, and valve bounce, during the closing phase. These effects not only induce substantial modifications to the valve lift curve but also increase the mechanical stress on critical components such as the valve and rocker arm, thereby elevating the risk of failure. Moreover, the timing system substantially contributes to overall engine losses due to frictional energy dissipation, which results from the numerous interactions between moving components. The present works aims at developing a
Tarchiani, Marco, Pizzicori, Alessio, Raspanti, Sandro, Romani, Luca, Meli, Enrico, Ferrara, Giovanni, Trassi, Paolo
Experimental analysis of wheel bearing friction losses under realistic driving cycles on a component and roller test bench2025-32-0100To be published on 11/03/2025
The ongoing electrification of vehicle powertrains brings attention to components with a minor contribution to overall friction losses in research and development. To optimize the overall energy efficiency, it is essential to analyze and reduce the losses in these components. Wheel bearings are of particular interest in this context, as their friction losses affect both the driving and recuperation phases. These losses are dependent on temperature, mechanical loads and the bearing mounting situation into the vehicle. The analysis of friction losses and their dependency on the factors mentioned above is usually conducted by measurements on component test benches to allow an isolated evaluation. In contrast, the friction losses of the complete drive system are measured on powertrain or roller test benches. In this context, the factors affecting the losses in wheel bearings may deviate from the measurements obtained on component test benches. The purpose of this paper is to analyses the
Hartmann, Lukas, Erxleben, Lars, Rebesberger, Ron, Henze, Roman, Sturm, Axel
Simulation study of wheel bearing friction losses at vehicle level2025-01-0399To be published on 10/07/2025
With the ongoing electrification of vehicles, components contributing a minor share of overall drivetrain losses are coming into focus. Analyzing these losses is crucial for enhancing the energy efficiency of modern vehicles and meeting the increasing demands for sustainability and extended driving range. These components include wheel bearings, whose friction losses are influenced by parameters such as temperature, mechanical loads, and mounting situation. Therefore, it is essential to analyze the resulting friction losses and their dependence on the mentioned influencing parameters at an early stage of development, both through test bench measurements and with the help of simulation models. To achieve these objectives, this submission presents a methodology that combines test bench measurements with a measurement-based simulation of the friction losses of wheel bearings occurring in the vehicle as a complete system under varying driving cycles and parameters. For this purpose, an
Hartmann, Lukas, Sturm, Axel, Henze, Roman, Notz, Fabian
Understanding End-of-Line NVH Scatter Bands in Electric Drives with High-Precision Simulations2025-01-0406To be published on 10/07/2025
An important characteristics of battery electric vehicles (BEVs) is their noise signature. Besides tire and wind noise, noise from auxiliaries as pumps, the electric drive unit (EDU) is one of the major contributors. The dynamic and acoustic behavior of EDUs can be significantly affected by production tolerances. The effects that lead to these scatter bands must be understood to be able to control them better and thus guarantee a consistently high quality of the products and a silent and pleasant drive. The paper discusses a simulation driven approach to investigate production tolerances and their effect on the NVH behavior of the EDU, using high precision transient multi-body dynamic analysis. This approach considers the main effects, influences, and the interaction from elastic structures of electric motor and transmission with accurate gear contact models in a fully coupled way. It servs as virtual end of line test, applicable in all steps of a new EDU development, by increasing
Klarin, Borislav, Schweiger, Christoph, Resch, Thomas
Development of a Design System for Wheel Bearings Including Prediction Functions for the Finite Element Method Using Lasso Regression and Bayesian Optimization2025-01-0365To be published on 09/15/2025
Wheel bearings play a critical role in providing smooth rotation when vehicles move in straight line and turning motions. Automotive electrification continues to accelerate, emphasizing specific market demands such as lightweighting, lower torque, and quietness. In addition to the above requirements, reduced development timing for automotive programs is required. Recently, the number of bearing manufacturers that utilize Model-Based Development (MBD) have been increasing in order to reduce development time. NTN has developed an integrated calculation automated system which is called Axle Bearing Integrated Calculation System (ABICS) that automates each step of the design processes for third generation hub bearings. After ABICS was released, man-hours per development project were reduced by 80 percent compared to previously used design flows in which each step of the design processes had been performed by a human. In order to further reduce development timing, even more focus has been
Kitada, Tatsuya, Barrett, Rob, Matsubuchi, Hiroki, Suma, Hiroto
Design Considerations for Wheel Bearing Outer Ring for Electric Vehicles2025-01-0367To be published on 09/15/2025
Electric vehicles (EVs) require improved drag performance from wheel bearings to achieve a longer range. EVs are heavier and have higher torque output compared to internal combustion-powered vehicles. Due to the increased weight and torque of EVs, there will be higher loads at the bearing-to-knuckle joint. These increased loads may necessitate higher clamp loads to maintain joint integrity. However, higher clamp loads can lead to distortion or reduced roundness of the wheel bearing outer ring. Such distortion permanently increases drag and reduces bearing life. Therefore, after vehicle corner assembly with higher clamp loads, it is critical to minimize outer ring distortion during the initial assembly and throughout the bearing's lifespan. This paper will cover the design considerations for the wheel bearing outer ring to minimize distortion, utilizing Computer-Aided Engineering (CAE) analysis for various designs. A Design of Experiments (DOE) will be conducted to understand the
Mandhadi, Chaitanya Reddy, Callaghan, Kevin, Sutherlin, Robert, Lee, Seungpyo, Lee, Yeonsik, Bovee, Benjamin
Dynamic Analysis of Automotive Wheel Bearings2025-01-0366To be published on 09/15/2025
Bearings are essential mechanical components that support external loads and facilitate rotational motion. With the increasing demand for high-performance applications in industries such as semiconductors, aerospace, and robotics, the need for accurate and robust performance evaluation has intensified. Traditionally, bearing performance has been assessed using static or quasi-static theoretical approaches. However, these methods are limited in their ability to capture time-dependent behaviors, which are critical in real-world applications. In this study, a rigid body dynamics analysis was proposed to evaluate the time-dependent behavior of bearings. The methodology was first applied to a deep groove ball bearing, and the results were compared with those obtained from bearing theory to validate the approach. Subsequently, the method was extended to an automotive wheel bearing, and the time-dependent contact angles and ball loads were analyzed under axial and radial loading conditions
Lee, Seungpyo
SAE Truck & Off-Highway Engineering: August 202525TOFHP0808/14/2025
A model of design efficiency How Cummins used modeling and other advanced design software to create its most efficient engines yet. Solving problems and seeking big ideas PACCAR's Phil Stephenson previews SAE COMVEC 2025 and offers insights into powertrain diversification, the role of AI, a software-defined future and the importance of people. Refurbishing high-voltage batteries for electric trucks Mercedes-Benz Trucks employs "like-new" reworked batteries to expand its spare parts portfolio and to inform future battery designs that are more sustainable. Editorial Hydrogen's humming in power generation Bosch invested in large-scale metal 3D printing Schaeffler optimizes rolling bearings for hydraulic and axle drives Natural gas infrastructure is scaling fast for HD fleets Cummins powers up the S17 genset SAE J3400/2 update brings quicker NACS charging Workhorse's W56 is the people's champ of electrified work vans Komatsu logs a new timber machine Product Briefs SPOTLIGHTS: Power
BEARING, BALL, ROD END, DOUBLE ROW, PRECISION, EXTERNAL THREAD, SELF-ALIGNING, AIRFRAME, TYPE II, -65 TO 300 °FAS21151G (Current)08/11/2025
ACBG Rolling Element Bearing Committee
Schaeffler optimizes rolling bearings for hydraulic and axle drives25TOFHP08_0608/01/2025
Rolling bearings with optimized friction and performance characteristics can have a significant influence on reducing the power loss, design envelope and weight of hydraulic motors and pumps, gearboxes and axles in construction machinery. If correctly designed, rolling bearings can make a significant contribution to reducing carbon dioxide emissions. Most construction machinery is still operated conventionally, using diesel engines and hydraulic components. In the widely used adjustable axial piston pumps and motors, the input and output shaft are usually supported by two tapered roller bearings that are adjusted against each other. When designing the bearing support, it is advisable to reduce the preload to precisely the required minimum allowed by the load spectrum. The lower bearing preload leads to permanently lower axial forces between the tapered roller end face and inner ring rib and, therefore, to a corresponding reduction in frictional torque.
Scharting, Stefan
Balancing Machines: Tooling Design CriteriaARP4163A (Historical)07/09/2025
This document establishes general design criteria, tolerances, and limits of application for tooling, fixtures, and accessories for mounting and driving gas turbine engine rotors on horizontal and vertical balancing machines.
EG-1A Balancing Committee
Improving Gearbox Acoustics through Elastomer-Based Bearing Damping2025-01-032307/02/2025
This study analyses the effect of external damping of roller bearings on the acoustic behaviour of gearboxes in electric powertrains. The growing use of electric vehicles has increased the importance of reducing gearbox noise, as the lack of noise masking from internal combustion engines and the higher operating speeds of electric motors exacerbate the acoustic challenges. Gearbox noise, which is primarily caused by tooth mesh excitation and its transmission through shafts and bearings, requires strategies to minimise its impact on vehicle comfort and performance. External damping is achieved through the integration of specific elements at the circumference of the outer bearing ring. These elements are utilised to modify the vibration transfer behaviour of the bearing assembly. This, in turn, can lead to a reduction in both structure-borne and airborne noise emissions at the gearbox housing. A test design was created to quantify the effects of different damping configurations. This
von Schulz, Kai, Linde, Tilmann, Jäger, Steffen
Common Pitfalls When Specifying Bearings for Medical DevicesTBMG-5344307/01/2025
Engineering precision is an art of nuance — especially when it comes to selecting the right bearing for medical devices. What begins as a straightforward specification process quickly becomes a complex yet familiar puzzle of competing requirements. Oftentimes, engineers discover that a bearing’s performance extends beyond its basic dimensional specs, involving considerations of material properties, system integration and supply chain dynamics.
Grease: Wide Temperature Range Lithium or Lithium Complex Thickened for Aircraft Wheel BearingsAMS3058B (Current)06/30/2025
This specification covers grease for use on aircraft wheel bearings. It also defines the quality control requirements to assure batch conformance and materials traceability and the procedures to manage and communicate changes in the grease formulation and brand. This specification invokes the Performance Review Institute (PRI) product qualification process. Requests for submittal information may be made to the PRI at the address in 2.2, referencing this specification. Products qualified to this specification are listed on a qualified products list (QPL) managed by the PRI. Additional tests and evaluations may be required by individual equipment builders before a grease is approved for use in their equipment. Approval and/or certification for use of a specific grease in aero and aero-derived marine and industrial applications is the responsibility of the individual equipment builder and/or governmental authorities and is not implied by compliance with or qualification to this
AMS M Aerospace Greases Committee
Comprehensive Management of Water Ingress in the Torque Overlay Steering System for Enhanced Reliability in Smart Trucks02-18-03-001606/02/2025
The reliability and performance of steering systems in commercial vehicles are paramount, given their direct impact on reducing hazardous driving and improving operational efficiency. The torque overlay system is designed to enhance driver control, feedback, and reduce driver fatigue. However, vulnerabilities such as water ingress under certain environmental conditions have raised significant reliability requirements. This article discusses the systematic investigation into how radial bearing sideloading led to the input shaft seal failing to contact the input shaft. Water was allowed a path to enter the TOS module, affecting the electronic sensor, and faulting out the ADAS functionality. Improvement to the bearing support and sealing design culminated to an enhanced TOS module package able to withstand testing procedures that mimic the environmental and use case situation which caused the ingress.
Bari, Praful Rajendra, Kintner, Jason
Improving the Working Performance of Sliding Friction Pairs Using Optimal Asymmetric Textures04-18-03-001605/29/2025
Optimizing the parameters of asymmetric textures (AT) designed on the surface of sliding frictional pairs (SFP) can make each texture more reasonably distributed. Thereby, the oil film thickness can be more stable; and the lubrication and load ability of SFP can be improved. To clarify this issue, based on the SFP’s lubricating model added by AT using the rectangular structure, parameters of AT including the angle between the horizontal axe and bottom surface (φij), the angle between the lateral axe and bottom surface (γij), and texture’s depth (hij) are optimized. The study results show that the parameters of φij, γij, and hij of AT optimized can create the p (hydrodynamic pressure of liquid) better than the symmetric textures. Significantly, the pmax and load ability of the liquid in the SFP using optimal AT have been greatly increased compared to the liquid in the SFP using the symmetric textures. Accordingly, the results are an important reference for the design and distribution of
Wang, Cuifang, Zhang, Lu
Wear Protection for Electrified Transmissions Using e-Fluids without Active Sulfur04-18-03-001505/08/2025
In electrified drivetrains, lubricants are commonly in contact with the motor and other electrical components as well as the gears and bearings. Copper, present in these electrical components, is susceptible to corrosion by fluids containing active sulfur, which can lead to catastrophic failure of the unit. Lubricating fluids for electric vehicles (referred to as e-fluids) must not cause corrosion and must maintain high performance while having suitable electrical conductivity, material compatibility, and heat transfer properties. We describe a new formulation without active sulfur that has recently entered the market, which can protect against copper corrosion. We show that this e-fluid can provide suitable wear protection under field trial conditions, and that the e-fluid provides improved wear protection in bearing (FE-8) tests compared to a traditional extreme pressure axle fluid (API GL-4). Surface analysis (X-ray photoelectron spectroscopy) measurements of the component surfaces
Hopper, Elizabeth R., Williams, Megan S., Gahagan, Michael
Leveraging Vision Language Models and Prompt Engineering for Bearing Defect Classification from Vibration Signals2025-01-012705/05/2025
Bearings are fundamental components in automotive systems, ensuring smooth operation, efficiency, and longevity. They are widely used in various automotive systems such as wheel hubs, transmissions, engines, steering systems etc. Early detection of bearing defects during End-of-Line (EOL) testing and operational phases is crucial for preventive maintenance, thereby preventing system malfunctions. In the era of Industry 4.0, vibrational, accelerometer, and other IoT sensors are actively engaged in capturing performance data and identifying defects. These sensors generate vast amounts of data, enabling the development of advanced data-driven applications and leveraging deep learning models. While deep learning approaches have shown promising results in bearing fault diagnosis, they often require extensive data, complex model architectures, and specialized hardware. This study proposes a novel method leveraging the capabilities of Vision Language Models (VLMs) and Large Language Models
Chandrasekaran, Balaji, Cury, Rudoniel
Condition Monitoring of High-Speed Rotating Machinery Using Digital Twins & Machine Learning Techniques2025-01-012805/05/2025
In the era of Industry 4.0, the maintenance of factory equipment is evolving with new systems using predictive or prescriptive methods. These methods leverage condition monitoring through digital twins, Artificial Intelligence, and machine learning techniques to detect early signs of faults, types of faults, locations of faults, etc. Bearings and gears are among the most common components, and cracking, misalignment, rubbing, and bowing are the most common failure modes in high-speed rotating machinery. In the present work, an end-to-end automated machine learning-based condition monitoring algorithm is developed for predicting and classifying internal gear and bearing faults using external vibration sensors. A digital twin model of the entire rotating system, consisting of the gears, bearings, shafts, and housing, was developed as a co-simulation between MSC ADAMS (dynamic simulation tool) and MATLAB (Mathematical tool). The gear and bearing models were developed mathematically, while
Rastogi, Sarthak, Singhal, Srijan, Ahirrao, Sachin, Milind, T. R.
NVH Improvement of the BEV Transmission by Altering Bearing Mounting Arrangement2025-01-010405/05/2025
As per metaphor, “The squeaky wheel gets the grease,” and in the case of Battery Electric Vehicles (BEVs), the transmission system has become the focal point for NVH (Noise, Vibration, and Harshness) improvements. With the engine being replaced by the near-silent electric motor, the noise generated by the transmission has become more prominent, demanding greater attention to noise reduction. This shift has created a pressing need for innovations in both design and manufacturing processes to enhance the overall quietness of the vehicle. As a result, ongoing advancements are being made to address and improve the NVH characteristics of BEV transmissions. Following paper will discuss the improvement in NVH achieved through a design innovation in the way bearings are installed and demonstrated a significant amount of improvement. We have used SMT MASTA as a simulation tool to predict the expected results and a Transmission Dyno test bench in an anechoic chamber to test the NVH performance
Pingale, Abhijeet, Soni, Jaldeep
Enhancing Efficiency in Manufacturing through Automated AI Agent-Based Bearing Defect Diagnostic System2025-01-015805/02/2025
Industrial bearings are critical components in aerospace, industrial, and automotive manufacturing, where their failures can result in costly downtime. Traditional fault diagnosis typically depends on time-consuming on-site inspections conducted by specialized field engineers. This study introduces an automated Artificial Intelligence virtual agent system that functions as a maintenance technician, empowering on-site personnel to perform preliminary diagnoses. By reducing the dependence on specialized engineers, this technology aims to minimize downtime. The Agentic Artificial Intelligence system leverages agents with the backbone of intelligence from Computer Vision and Large Language Models to guide the inspection process, answer queries from a comprehensive knowledge base, analyze defect images, and generate detailed reports with actionable recommendations. Multiple deep learning algorithms are provisioned as backend API tools to support the agentic workflow. This study details the
Chandrasekaran, Balaji
Recommended Wheel Tie Bolt Preload ProcedureARP5481A (Current)04/14/2025
This SAE Aerospace Recommended Practice (ARP) provides the recommended procedure for obtaining desired preloads in aircraft wheel tie bolts when mounting tires and assembling the wheel. It is generally referred to as the snug-angle bolted joint assembly procedure. It is also known as the “torque-turn” procedure in the heavy equipment ground vehicle industry.
A-5A Wheels, Brakes and Skid Controls Committee
A Wide Belt Correction Strategy for Belt-Whip and Wheel Ventilation Drag2025-01-877004/01/2025
The increased importance of aerodynamics to help with overall vehicle efficiency necessitates a desire to improve the accuracy of the measuring methods. To help with that goal, this paper will provide a method for correcting belt-whip and wheel ventilation drag on single and 3-belt wind tunnels. This is primarily done through a method of analyzing rolling-road only speed sweeps but also physically implementing a barrier. When understanding the aerodynamic forces applied to a vehicle in a wind tunnel, the goal is to isolate only those forces that it would see in the real-world. This primarily means removing the weight of the vehicle from the vertical force and the rolling resistance of the tires and bearings from the longitudinal force. This is traditionally done by subtracting the no-wind forces from the wind at testing velocity forces. The first issue with the traditional method is that a boundary layer builds up on the belt(s), which can then influence a force onto the vehicle’s
Borton, Zackery
A Sensitivity Study of Frequency Response Method for Setting Bearing Preload to Manufacturing and Design Variation2025-01-851804/01/2025
Roller bearings are used in many rotating power transmission systems in the automotive industry. During the assembly process of the power transmission system, some types of roller bearings (e.g., tapered roller bearings) require a compressive preload force. Those bearings' rolling resistance and lifespan strongly depend on the preload set during the installation process. Therefore, accurate preload setting can improve bearing efficiency, increase bearing lifespan, and reduce maintenance costs over the life of the vehicle. A new method for bearing preload measurement has shown potential for high accuracy and fast cycle time using the frequency response characteristics of the power transmission system. One open problem is the design of the production controller, which relies on a detailed sensitivity study of the system frequency response to changes in the bearing and system design parameters. Recently, an analytical model was developed for multi-row tapered roller bearings that includes
Gruzwalski, David, Mynderse, James
A Sensitivity Study of Frequency Response Method for Setting Bearing Preload Due to Uncontrollable Parameters2025-01-852004/01/2025
A new method for bearing preload measurement has shown potential for both high accuracy and fast cycle time using the frequency response characteristics of the power transmission system. One open problem is the design of the production controller, which relies on a detailed sensitivity study of the system frequency response to changes in the bearing and system design parameters. Recently, an analytical model was developed for multi-row tapered roller bearings that includes all appropriate bearing and power transmission system design parameters. During the assembly process, some of the parameters related to the roller positions cannot be controlled. These parameters include the actual position of the first roller compared to the vertical axis, the relative position of the rollers between the bearing rows, and others. This work presents a sensitivity analysis of the effects of those uncontrollable parameters on the analytical model. The sensitivity study determines the percentage change
Gruzwalski, David, Mynderse, James
Study of the Effects on Plain Bearings in Simulated Corrosion Tests Using Carbon Neutral Fuels2025-01-847004/01/2025
Many countries around the world are currently working toward carbon neutrality, which would reduce greenhouse gas emissions to net zero by 2050. To achieve carbon neutrality, the search for new fuels to replace gasoline has been active. This study focuses on hydrogen and methanol fuels and examines their effects on plain bearings when these fuels are used in internal combustion engines. Compared to gasoline, these fuels differ significantly in the composition of gases produced after combustion. It is assumed that nitric acid, etc. will be mixed in the engine oil when hydrogen is combusted whilst formic acid, etc. will be mixed in the engine oil when methanol fuel is combusted. For this reason, corrosion tests were conducted by adding nitric acid or formic acid solution to the engine oil then placing plain bearings in the deteriorated oil. The results confirmed that significant corrosion of the bismuth overlay coating occurred and subsequently the performance of plain bearings may
Kondo, Makoto, Kawaura, Hiroki, Shiroya, Tomoyasu, Watanabe, Airi
Thermal Simulation of Ball Bearing in Electric Drive Unit: A CFD Study Using Volume of Fluid and Mixed Timescale Coupled Conjugate Heat Transfer Analysis2025-01-817804/01/2025
The drive unit of electric vehicles is a complex system consisting of an electric motor and a gear train, which work together to provide the necessary power for vehicle propulsion. One essential component within this system is the ball bearing, which supports the rotating components such as gears and shafts. This study focuses on the thermal simulation of a ball bearing within the drive unit conducted using the Volume of Fluid (VOF) method coupled with mixed timescale Conjugate Heat Transfer (CHT) in Simerics-MP+ to reduce the computational time while ensuring accuracy in the analysis. The Computational Fluid Dynamics (CFD) approach considers the geometrical details and clearances of the inner race, outer race, cage, and ball within the ball bearing. By accounting for the relative motions between these components, it can accurately model the film formation of the lubricating oil and its impact on heat removal from the bearing. The simulations are conducted at two different shaft speeds
Ballani, Abhishek, Motin, Abdul, Dhar, Sujan, Ganamet, Alain, Maiti, Dipak, Ranganathan, Raj, Pandey, Ashutosh
Platform Development of Fuel Cell Air Compressors2025-01-854704/01/2025
Hydrogen fuel cell is one of paths to achieve carbon neutrality transportation. In the last two decades, significant improvements have been made in compactness, efficiency and durability of fuel cell systems. For heavy duty truck applications, a life span similar to heavy duty diesel engines is required. As a critical component in the fuel cell system, air compressors play an important role to meet fuel cell systems’ high efficiency and durability requirements. In this paper, a holistic approach has been taken to develop a series of airfoil bearing centrifugal compressors for a wide range of applications from forklift, passenger vehicles to commercial vehicles, and achieve high efficiency and durability of one million start-stops. In the new platform development, cooling circuit was optimized so that the external cooling air circuit for the rotor and air bearings is no longer needed, which resulted in 4% efficiency improvement. Hollow rotor structure was adopted to achieve lightweight
Wang, Qianzhen, Yuan, Xixin, Tao, Zhang, Feng, Jin Zeng, Wang, Juan, Xiao, Yong, Zhou, Lei, Xin, Jun
Steel Bars, Wire, Forgings, Mechanical Tubing and Forging Stock, Corrosion Resistant 14Cr - 2.1Mo - 0.30Cb (Nb) - 1.0V (1.05 - 1.15C) Premium Aircraft Quality for Bearing Applications, Double Vacuum Melted, AnnealedAMS5900D (Current)02/25/2025
This specification covers a premium aircraft-quality, corrosion-resistant steel in the form of bars, wire, forgings, mechanical tubing, and forging stock.
AMS F Corrosion and Heat Resistant Alloys Committee
Petroleum Base Instrument Bearing Lubricant Viscosity 15AMS3055C (Current)02/25/2025
This specification covers the requirements for a refined paraffinic petroleum-base lubricant.
AMS B Finishes Processes and Fluids Committee
A Comparative Study on the Working Efficiency of Journal Bearing Employing Different Micro-Textures04-18-02-001102/19/2025
This study proposed the different micro-textures of the SC (square cylinder), SWS (square wedge shape), HS (hemispherical shape), and CR (cylindrical round) to improve the working efficiency of the journal bearing. A hydrodynamic lubrication model of the journal bearing under the impact of the changing dynamic loads is established to analyze the performance of micro-textures. The maximum oil film pressure and minimum frictional force in the journal bearing are selected as two evaluation indices. Some outstanding research results show that all the SC, SWS, HS, and CR added on the bearing surface improved the working efficiency of the journal bearing better than without the micro-textures. Moreover, the HS also improved the working efficiency of the journal bearing better than other structures of SC, SWS, and CR. To optimize the working efficiency of the journal bearing using HS, the dimension ltex and depth htex of HS should be selected and designed in a range of 3.6 < ltex ≤ 3.9 mm and
Song, Fengxiang, Nguyen, Vanliem, Liu, Yaxi
A Study on Powertrain Modes for Optimizing the NVH Performance2024-28-018712/05/2024
The stiffness and positioning of engine mounts are crucial in determining the powertrain rigid body modes and kinetic energy distribution. Therefore, optimizing these mounts is essential in the automotive industry to separate the torque roll axis (TRA) and minimize vibration. This study aims to enhance mount locations by isolating the engine rigid body modes and predicting the inter-component force (ICF) and transfer function of the vehicle. The individual ICFs for engine mountings are calculated by applying a unit force at the bearing location. Critical frequencies are identified where the amplification exceeds the unit force at the mounting interface between the engine and the frame. The transfer function approach is utilized to assess the vibration at the handlebar. Both ICF and transfer functions analyze the source and path characteristics linked to critical response frequencies. This understanding aids in enhancing mounting positions to minimize vibration levels, thereby enhancing
Jha, Niraj Kumar, Yeezaku, Antony Neomin, Victor, Priyanka Esther, Krishnamurthy, Govindasamy
An Innovative Method to Measure Tapered Roller Bearing Preload in Manual Transmission & Identification of Crucial Influencing Parameters2024-28-019712/05/2024
In manual transmission, bearing preload is a vital factor for optimum durability and performance of tapered roller bearings (TRB). To achieve better optimization of bearing preload, a precise measurement method is a minimum requisite. This technical paper investigates multiple ideas and develops a novel methodology for accurate bearing preload measurement, overcoming the challenges produced by the complexity of transmission design. This paper provides a systematic approach to bearing preload measurement in manual transmission along with identification of key parameters responsible for influencing bearing preload, such as rigidity and fit of the components. A comprehensive experimental study at both part level and system level was conducted to quantify the effects of above-mentioned parameters on preload and transmission performance. Furthermore, the paper explores the effect of bearing preload optimization on the durability performance of the transmission unit.
Gaurav, Kumar, Kumar, Arun, Singh, Maninder Pal, Dhawan, Soumil, Singh, Kulbir, Kumar, Krishan, Singh, Manvir
BEARING, ROLLER, NEEDLE, SINGLE ROW, THIN SHELL TYPE II, ANTIFRICTION, INCHAS24462C (Current)12/05/2024
ACBG Rolling Element Bearing Committee
Bearings, Roller, Needle, Airframe, Antifriction, InchAS39901D (Current)12/03/2024
This standard covers the requirements for non-separable, airframe antifriction needle bearings and corrosion-resistant and traditional materials intended for use in flight vehicle control systems with radial loads.
ACBG Rolling Element Bearing Committee
BEARING, ROLLER, NEEDLE, TRACK ROLLER, SEALED, TYPE X, ANTIFRICTION, INCHAS21442C (Current)12/03/2024
ACBG Rolling Element Bearing Committee
BEARING, ROLLER, NEEDLE-SINGLE ROW, HEAVY DUTY, TRACK ROLLER, TYPE V, ANTIFRICTION, INCHAS24465B (Current)12/03/2024
ACBG Rolling Element Bearing Committee
Bearings, Plain, Self-Aligning, Self-Lubricating, High Speed Oscillation -65 to +160 °F General Specification ForAS81819B (Current)11/21/2024
This standard covers the requirements for spherical, self-aligning, self-lubricating bearings that are for use in the ambient temperature range of -65 to +160 °F (-54 to +71 °C) at high cyclic speeds. The scope of the standard is to provide a liner system qualification procedure for helicopter sliding bearings defined and controlled by source control drawings. Once a liner system is qualified, the source controlled bearings may be further tested under application conditions.
ACBG Plain Bearing Committee
Steel Bars, Forgings, Mechanical Tubing and Forging Stock 4.1Cr - 4.2Mo - 1.0V (0.80 - 0.85C) (M-50) Premium Aircraft-Quality for Bearing Applications, Double Vacuum MeltedAMS6491G (Current)11/06/2024
This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.
AMS E Carbon and Low Alloy Steels Committee
Steel, Corrosion-Resistant, Bars, Wire, Mechanical Tubing, Forgings and Forging Stock 15.5Cr - 1.5Si - 0.3Mo - 0.1N (0.45 - 0.60C) for Bearing ApplicationsAMS5926A (Current)10/28/2024
This specification covers a corrosion- and heat-resistant steel in the form of bars, wire, mechanical tubing, forgings, and forging stock.
AMS F Corrosion and Heat Resistant Alloys Committee
Monitoring the Thermal Aging of Rubber Bearings Using Virtual Temperature Sensors2024-01-509910/21/2024
Recurring thermal loads in a vehicle can lead to the failure of rubber bearings due to thermal aging within the expected vehicle lifetime. The disadvantages of a preventive or reactive maintenance strategy are high warranty costs and low customer satisfaction, respectively. This work proposes a predictive maintenance system, which monitors the thermal aging of rubber bearings and indicates their timely replacement. Since no real temperature sensors are installed at rubber bearings in production vehicles, virtual temperature sensors are used to monitor component temperatures during customer operation. As a virtual sensor, a feedforward neural network is trained on measurement data in order to learn to predict the component temperatures of several rubber bearings in a combustion engine vehicle based on existing vehicle signals. The neural network achieves an average mean absolute error of 1.78 K and a coefficient of determination of 0.95 over all components after hyperparameter tuning
Freytag, Lukas, Rottengruber, Hermann, Enke, Wolfram
Comprehensive Analysis of Needle Bearing Failures in Fuel Transfer Pumps: Insights from Testing and Finite Element Analysis03-18-01-000410/09/2024
This study investigates the failure mechanisms of needle bearings within fuel transfer pump assemblies through a comprehensive approach combining endurance testing, detailed inspection, the Dykem blue method, proximity sensors, and finite element analysis (FEA). The findings reveal critical insights into the causes of failure, highlighting significant axial displacement, with a maximum of 0.37 mm measured by proximity sensors. The Dykem technique identified distinct wear patterns across various components, pinpointing areas of high stress and potential failure. Detailed bearing inspections uncovered trunnion damage and abrasive wear, corroborated by FEA, which quantified displacements of 0.144 mm in the x-direction, 0.030 mm in the y-direction, and 0.015 mm in the z-direction. The primary operational factors contributing to bearing failure were contamination and inadequate axial control. These insights are pivotal, as they align with and expand upon established literature on bearing
Kaliyanda, Aneesh
Achieving Exceptional Precision with Air Bearing Motion SystemsTBMG-5170810/01/2024
Knowledge Push Mechanism of Rolling Bearing Fault Diagnosis Employing Deep Residual Network Architecture2024-01-600409/11/2024
Rolling bearings play a critical role in rotating machinery, with their fatigue life directly impacting equipment’s operational reliability. This underscores the significant engineering application value of “fault diagnosis” (FD) technology for rolling bearings in mechanical, automation, and aerospace domains. Literature reviews highlight that a substantial portion of failures in machinery such as jet turbine engines, wind turbines, gear reducers, and induction machines are attributable to bearing issues. Early fault detection and preventive maintenance are therefore imperative for ensuring the smooth operation of rotating machinery. This paper focuses on rolling bearings, delving deep into FD technology using machine learning principles. It analyses the structure and common failure modes of rolling bearings, discussing an FD method based on machine learning. Specifically, the SE-DRN (“squeeze-exclusion deep residual network”) approach is employed, leveraging “variational modal
Muin, Abdullah-Al, Khan, Shahrukh, Miah, Md Helal
Evaluation of Friction Torque in Tapered Roller Bearings2024-01-304709/08/2024
A bearing is a mechanical component that transmits rotation and supports load. Depending on the type of rotating mechanism, bearings are categorized into ball bearings and tapered-roller bearings. Tapered-roller bearings are superior to ball bearings in load-bearing capabilities. They are used in applications where high loads, such as, the wheel bearings for commercial vehicles and trucks, aircraft, high-speed trains, and heavy-duty spindles for heavy machinery must be supported. The demand for reducing the friction torque in automobiles has recently increased owing to carbon-emission regulations and fuel-efficiency requirements. Therefore, research on the friction torque of bearings is essential; studies have been conducted on lubrication, friction, and contact in tapered-roller bearings. There have also been studies on lip friction, roller misalignment, and so on; however, research on the influence of roller geometries and material properties is scarce. This study investigated the
Lee, Seungpyo, An, Hyun Gyu
Development of Aluminum-Based Metal Matrix Composite for Dry Bearings Reinforced with Titanium Dioxide and Silicon Carbide2024-01-509109/02/2024
Metal matrix composites (MMCs) have evoked a keen interest in recent times for their potential applications in automotive and aerospace industry components. One such particulars include dry sliding bearings, which have widespread applications in various industries due to their self-lubricating properties, high wear resistance, and low maintenance requirements. The wear as a consequence of metal-to-metal friction can have a detrimental effect, expediting malfunctions or much more adverse spin-offs on the whole system. This study focuses on the development and characterization of a novel dry bearing material composed of a MMC consisting of aluminum (Al), titanium dioxide (TiO2), and silicon carbide (SiC). Tribological tests revealed a low friction coefficient, ensuring efficient and reliable operation. The results indicate the enhancement of MMC’s performance and durability in dry bearings, contributing to the efficiency and reliability of engineering systems. The study not only
Ravi Raj, V., Dhivya Praban, S. V., Jayasooriya, M., Sairam, T. S.
Steel Bars, Forgings, Mechanical Tubing and Forging Stock 4.0Cr - 4.2Mo - 1.0V (0.77 - 0.85C) (M-50) Premium Aircraft-Quality for Bearing Applications Consumable Electrode Vacuum MeltedAMS6490K (Current)08/29/2024
This specification covers a premium aircraft-quality, low-alloy steel in the form of bars, forgings, mechanical tubing, and forging stock.
AMS E Carbon and Low Alloy Steels Committee
The Crucial Role of Bearings in the Humanoid Robotics RevolutionTBMG-5119508/01/2024
BEARING, BALL, ROD END, DOUBLE ROW, PRECISION, INTERNAL THREAD, SELF-ALIGNING, AIRFRAME, TYPE IV, -65 TO 300 °FAS21153F (Current)07/02/2024
ACBG Rolling Element Bearing Committee
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