Author: Rui DaiPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Investigation of Damage Initiation and Propagation from Non-metallic Inclusions in Raceway Subsurface of Wind Turbine Gearbox Bearings
Author: Rui DaiEffect of Surface Traction and Non-metallic Inclusions on the Premature Failure of Wind Turbine Gearbox Bearings
Author: Hamza Abdulrasool Hussain Al-TameemiPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Wear Analysis of Wind Turbine Gearbox Bearings
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The objective of this effort was to investigate and characterize the nature of surface damage and wear to wind turbine gearbox bearings returned from service in the field. Bearings were supplied for examination by S. Butterfield and J. Johnson of the National Wind Technology Center (NREL), Boulder, Colorado. Studies consisted of visual examination, optical and electron microscopy, dimensional measurements of wear-induced macro-scale and micro-scale features, measurements of macro- and micro-scale hardness, 3D imaging of surface damage, studies of elemental distributions on fracture surfaces, and examinations of polished cross-sections of surfaces under various etched and non-etched conditions.
Investigation of Multiple Data Streams for Gearbox Bearing Fault Prediction Through Machine-learning Models
Author: Lindy WilliamsPublisher:
ISBN:
Category : Structural analysis (Engineering)
Languages : en
Pages : 0
Book Description
Dynamics and Vibration Analyses of Gearbox in Wind Turbine
Author: Qingkai HanPublisher: Springer
ISBN: 9811027471
Category : Technology & Engineering
Languages : en
Pages : 168
Book Description
This book explores the dynamics and vibration properties of gearboxes, with a focus on geared rotor systems. It discusses mechanical theories, finite-element based simulations, experimental measurements and vibration signal processing techniques. It introduces the vibration-resonance calculation method for the geared rotor system in wind turbines and load sharing of the planetary gear train, and offers a method for calculating the vibrations of geared rotor systems under either internal excitations from gear sets or external loads transferred from wind loads. It also defines and elaborates on parameter optimization for planetary gear systems based on the torsional dynamics of wind-turbine geared rotor systems. Moreover, it describes experimental measurements of vibrations on the wind-turbine gearbox performed on the test rig and on site, and analyzes the vibration signals of different testing points, showing them in both time and frequency domains. Lastly, it lists the gear coupling frequencies and fault characteristic frequencies from the vibrations of the gearbox housing. The technologies and results presented are valuable resources for use in dynamic design, vibration prediction and analysis of gearboxes and geared rotor systems in wind turbines as well as many other machines.
Main Bearing Replacement and Damage - A Field Data Study on 15 Gigawatts of Wind Energy Capacity
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
This study seeks to establish a comprehensive baseline of knowledge for the replacement and damage of main bearings in wind turbines. The purpose of this report is to provide a high-level summary of the data set, methodology, and results of this work. Full technical details and an extended analysis will be made available in a future publication. We collected data on main bearing replacements and reported damage from industrial partners based in Europe and the United States. In total, we obtained data for 167 wind power plants, with a combined capacity of 15.3 gigawatts (GW). Most of the data set was comprised of land-based, three-point mount, spherical roller bearings. Within this data set were 689 instances of main bearing replacement. Analysis was undertaken in two parts: first, a statistical analysis of the main bearing time-to-replacement data using survival analysis techniques; second, quantitative and qualitative analyses of the obtained damage information. Our results showed that 10% of a fixed main bearing population would be expected to have been replaced by 10.5 years. This is close to half of the 20-year design value. Fitted parametric distributions then indicated that by year 20, between 22% and 25% of main bearings are expected to have been replaced. Analysis of the damage reports revealed spalling to be the main type of damage listed. The additional presence of surface damage in the collected data indicates that at least part of the spalling cases are likely due to surface-initiated rolling contact fatigue. At this stage is not clear what proportion of spalling cases result from "wear induced", surface-initiated and subsurface-initiated rolling contact fatigue. While this work provides important insights into the current state of main bearing replacements and damage, many questions remain. An ongoing and expanding data collection and analysis effort focused on wind turbine main bearings is therefore recommended.
Analysis of the Premature Failure of Wind Turbine Gearbox Bearings
Author: Thomas BruceBearing Fault Detection on Wind Turbine Gearbox Vibrations Using Generalized Likelihood Ratio-Based Indicators: Preprint
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Studies in condition monitoring literature often aim to detect rolling element bearing faults because they have one of the biggest shares among defects in turbo machinery. Accordingly, several prognosis and diagnosis methods have been devised to identify fault signatures from vibration signals. The underlying idea behind traditional indicators often revolves around tracking both cyclostationarity and abnormal impulses in the vibration signals without distinguishing the two. A recently proposed method to capture the rolling element bearing degradation lays out the groundwork for new indicator families utilizing generalized likelihood ratio test. This novel approach exploits the cyclostationarity and the impulsiveness of vibration signals independently in order to estimate the most suitable indicators for a given fault. However, the method has yet to be tested on complex experimental vibration signals such as those of a wind turbine gearbox. In this study, the approach is applied to the NREL Wind Turbine Gearbox Condition Monitoring Round Robin Study data set for bearing fault detection purposes. The data set is measured on an experimental test rig of a wind turbine gearbox, hence the complexity of the vibration signals is similar to a real case. Furthermore, the new indicators are also tested with signals that carry multiple fault signatures. The outcome demonstrates that the proposed method is capable of distinguishing between healthy and damaged vibration signals measured on a complex wind turbine gearbox.
Wind Turbine Gearbox Failure Modes - A Brief (Presentation).
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 26
Book Description
Wind turbine gearboxes are not always meeting 20-year design life. Premature failure of gearboxes increases cost of energy, turbine downtime, unplanned maintenance, gearbox replacement and rebuild, and increased warranty reserves. The problem is widespread, affects most Original Equipment Manufacturers, and is not caused by manufacturing practices. There is a need to improve gearbox reliability and reduce turbine downtime. The topics of this presentation are: GRC (Gearbox Reliability Collaborative) technical approach; Gearbox failure database; Recorded incidents summary; Top failure modes for bearings; Top failure modes for gears; GRC test gearbox; Bearing nomenclature; Test history; Real damage; Gear sets; Bearings; Observations; and Summary. 5 refs.
Evaluation of Repaired Gas Turbine Engine Bearings Demonstrates Absence of Subsurface Fatigue Propagation in Appropriately Designed Applications
Author: Edgar StreitPublisher:
ISBN:
Category : Bearing repair
Languages : en
Pages : 13
Book Description
Refurbishment of aerospace gas turbine engine bearings is a well established process regularly used to ensure asset availability. Repairs typically follow four well established basic levels. Level one generally requires detailed inspection in accordance with agreed criteria. Level two commonly involves replacement of rolling elements, refinishing of raceway surfaces and re-plating of bearing cages as appropriate. Level three involves the use of raceway grinding in the event that standard honing is insufficient to achieve required product quality. Level four is reserved for cases where one of the bearing rings is replaced. Results from detailed study of product following completion of full scale testing, repair per levels two and four, and continued testing is presented herein. Results demonstrate the absence of subsurface fatigue propagation. Test results conclude the commonly recognized acceptability of the repair methods noted and further support previously published theories regarding infinite fatigue theory. Reference to previously published findings describing expected symptoms of subsurface fatigue propagation are reviewed to support findings.