循环变载荷下润滑脂润滑点接触的膜厚衰减和磨损行为

Yiming Han, Jing Wang, Hengrui Du, Weimin Li, Jingxin Zhao, Zongyi Bai, Meng Hu, Haichao Liu
{"title":"循环变载荷下润滑脂润滑点接触的膜厚衰减和磨损行为","authors":"Yiming Han, Jing Wang, Hengrui Du, Weimin Li, Jingxin Zhao, Zongyi Bai, Meng Hu, Haichao Liu","doi":"10.3390/lubricants12020042","DOIUrl":null,"url":null,"abstract":"For wind turbine applications, there is a cyclic load-varying process between rolling elements and raceways in pitch bearings. This kind of motion can also lead to radial fretting. However, this is seldom addressed under grease-lubricated conditions in the literature. In this study, grease-lubricated point contact problems have been investigated experimentally under cyclic load-varying conditions. The findings revealed that as the load-varying range diminishes, the variation in grease film distribution becomes more subtle and the rate of discharge of thickener fiber clusters in the stick zone decelerates. This is due to the fact that the rate of change in the Hertz contact radius is reduced and the migration of grease is weakened during the unloading process. Due to the large apparent viscosity of grease with a high soap content, entrapped grease is not easily discharged during loading, and the thickness of the film in the stick zone progressively increases as the soap content of the grease is augmented. This also causes the variable load zone to wear out more easily. As the grease is subjected to repeated loading and unloading, there is a gradual reduction in film thickness, and larger thickener fiber clusters tear, resulting in a flattened form and shear thinning. Grease containing sulphur–phosphorus additives demonstrates a superior effect on reducing fretting wear within the large variable load range but generally proves effective for smaller load-varying ranges. This study may offer insights into the degradation of grease under variable load motion and methods to prevent radial fretting wear.","PeriodicalId":502914,"journal":{"name":"Lubricants","volume":"12 2","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Film Thickness Decay and Wear Behavior of Grease-Lubricated Point Contact under Cyclic Variable Loads\",\"authors\":\"Yiming Han, Jing Wang, Hengrui Du, Weimin Li, Jingxin Zhao, Zongyi Bai, Meng Hu, Haichao Liu\",\"doi\":\"10.3390/lubricants12020042\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"For wind turbine applications, there is a cyclic load-varying process between rolling elements and raceways in pitch bearings. This kind of motion can also lead to radial fretting. However, this is seldom addressed under grease-lubricated conditions in the literature. In this study, grease-lubricated point contact problems have been investigated experimentally under cyclic load-varying conditions. The findings revealed that as the load-varying range diminishes, the variation in grease film distribution becomes more subtle and the rate of discharge of thickener fiber clusters in the stick zone decelerates. This is due to the fact that the rate of change in the Hertz contact radius is reduced and the migration of grease is weakened during the unloading process. Due to the large apparent viscosity of grease with a high soap content, entrapped grease is not easily discharged during loading, and the thickness of the film in the stick zone progressively increases as the soap content of the grease is augmented. This also causes the variable load zone to wear out more easily. As the grease is subjected to repeated loading and unloading, there is a gradual reduction in film thickness, and larger thickener fiber clusters tear, resulting in a flattened form and shear thinning. Grease containing sulphur–phosphorus additives demonstrates a superior effect on reducing fretting wear within the large variable load range but generally proves effective for smaller load-varying ranges. This study may offer insights into the degradation of grease under variable load motion and methods to prevent radial fretting wear.\",\"PeriodicalId\":502914,\"journal\":{\"name\":\"Lubricants\",\"volume\":\"12 2\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2024-02-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Lubricants\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3390/lubricants12020042\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Lubricants","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/lubricants12020042","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0

摘要

在风力涡轮机应用中,变桨轴承的滚动体和滚道之间存在周期性载荷变化过程。这种运动也会导致径向摩擦。然而,文献中很少涉及油脂润滑条件下的这一问题。本研究对循环载荷变化条件下的油脂润滑点接触问题进行了实验研究。研究结果表明,随着载荷变化范围的减小,润滑脂膜分布的变化会变得更加微妙,粘滞区增稠剂纤维簇的排出速度也会减慢。这是由于赫兹接触半径的变化率降低,卸载过程中润滑脂的迁移减弱。由于皂含量高的润滑脂表观粘度大,因此在加载过程中夹带的润滑脂不易排出,而且随着润滑脂皂含量的增加,粘稠区的油膜厚度也会逐渐增加。这也会导致可变载荷区更容易磨损。随着润滑脂的反复加载和卸载,油膜厚度会逐渐减少,较大的增稠剂纤维簇会撕裂,从而形成扁平状和剪切变薄。含硫磷添加剂的润滑脂在大负载变化范围内减少摩擦磨损的效果更佳,但在较小的负载变化范围内也普遍有效。这项研究有助于深入了解润滑脂在可变载荷运动下的降解情况以及防止径向摩擦磨损的方法。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Film Thickness Decay and Wear Behavior of Grease-Lubricated Point Contact under Cyclic Variable Loads
For wind turbine applications, there is a cyclic load-varying process between rolling elements and raceways in pitch bearings. This kind of motion can also lead to radial fretting. However, this is seldom addressed under grease-lubricated conditions in the literature. In this study, grease-lubricated point contact problems have been investigated experimentally under cyclic load-varying conditions. The findings revealed that as the load-varying range diminishes, the variation in grease film distribution becomes more subtle and the rate of discharge of thickener fiber clusters in the stick zone decelerates. This is due to the fact that the rate of change in the Hertz contact radius is reduced and the migration of grease is weakened during the unloading process. Due to the large apparent viscosity of grease with a high soap content, entrapped grease is not easily discharged during loading, and the thickness of the film in the stick zone progressively increases as the soap content of the grease is augmented. This also causes the variable load zone to wear out more easily. As the grease is subjected to repeated loading and unloading, there is a gradual reduction in film thickness, and larger thickener fiber clusters tear, resulting in a flattened form and shear thinning. Grease containing sulphur–phosphorus additives demonstrates a superior effect on reducing fretting wear within the large variable load range but generally proves effective for smaller load-varying ranges. This study may offer insights into the degradation of grease under variable load motion and methods to prevent radial fretting wear.
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信