Influences of lubricants and bearing surface configuration under bolt head on self-loosening of bolted joints

Shinji Hashimura, Kyoichi Komatsu, Takefumi Otsu, Yujiro Sekido

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)


In recent years, self-loosening detail mechanisms of bolted joints had been revealed using three dimensional FE analysis in which the bolts and the nuts have almost perfect configurations geometrically. However the configurations of actual bolts and nuts have certainly errors. Wear on contact surfaces also occurs in the actual bolted joint. Hence it is not easy to accurately simulate the actual bolted joint by only FEM. In this study, an influence of lubricants on seif-loosening characteristics have been investigated in order to understand actual phenomena in self-loosening process. The self-loosening tests for a hexagon head cap screw M10 due to transverse vibration were performed under lubricated conditions by Machine oil ISO VG46, Molybdenum disulfide grease and Polyisobuthylene which is used as a special lubricant for bolt tightening. A bearing surface configuration of the bolt was controlled in this study. The results showed that the bolted joints lubricated by Polyisobuthylene had a higher resistance for self-loosening than the bolted joints lubricated by Molybdenum disulfide grease and Machine oil ISO VG46. The number of cycle until loosening depended on bearing surface configurations.

Original languageEnglish
Pages (from-to)205-216
Number of pages12
JournalToraibarojisuto/Journal of Japanese Society of Tribologists
Issue number3
Publication statusPublished - 2017


  • Bearing surface configuration
  • Bolted joint
  • Loosening torque
  • Lubricant
  • Self-loosening

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry


Dive into the research topics of 'Influences of lubricants and bearing surface configuration under bolt head on self-loosening of bolted joints'. Together they form a unique fingerprint.

Cite this