Analysis of additional load and fatigue life of preloaded bolts in a flange joint considering a bolt bending load

Okorn, Ivan (author), Nagode, Marko (author), Klemenc, Jernej (author), Oman, Simon (author)

The influence of the working load on the dynamic loading of the bolt was investigated in our study for two cases of flange joints. The analytical calculation according to the Verein Deutscher Ingenieure (VDI) 2230 recommendation and the numerical analysis using the finite element method (FEM) were performed for a model of a four-bolt joint. To verify the FEM analysis, the forces in the bolts were measured during preloading and during the application of the working load on the test rig. Based on the analytical and numerical results, the influence of the working load application point on the bolt load and its fatigue life was analysed for different cases. Comparison of the results shows that the analytical method overestimates the additional bolt stresses at low working load, mainly due to the extremely large fraction of bending stress. As the working load increases, the differences between the two methods decrease, but only for the reason that the analytical method can only linearly scale the overestimated results at lower working load, and FEM analysis, on the other hand, shows a progressive increase of the additional stress in the bolt at higher working loads due to the spreading of the flange. It is also shown that a high washer significantly increases the fatigue life of the bolt for two reasons: (i) a high washer reduces the additional stress in the bolt, and (ii) the high washer shifts the critical fatigue point from the thread area to the transition of the bolt shank to the head.

• Language: English
• Keywords: bolted joint, flange joint, preload, resilience, working load, load introduction factor, alternating stress range, fatigue life
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 20 str.
• Numbering: Vol. 11, iss. 3, art. 449
• PID: 20.500.12556/RUL-126175
• UDC: 620.178.3:519.61(045)
• ISSN on article: 2075-4701
• DOI: 10.3390/met11030449
• COBISS.SI-ID: 59147523
• Publication date in RUL: 13.04.2021

Record is a part of a journal

• Title: Metals
• Shortened title: Metals
• Publisher: MDPI AG
• ISSN: 2075-4701
• COBISS.SI-ID: 15976214

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 09.03.2021

Secondary language

• Language: Slovenian
• Keywords: vijačna zveza, prirobnična zveza, prednapetje, togost vijačne zveze, delovna obremenitev, faktor prijemališča sile, amplituda napetosti, doba trajanja

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0182
• Name: Razvojna vrednotenja