Untersuchung der Kraftverhältnisse von Bridenanbindungen für Ladekrane

Translated title of the contribution: Analysis of load factors from stud bolt connections for loader cranes

Daniel Thöny

Research output: ThesisMaster's Thesis

Abstract

The loader crane is mounted on the truck frame with stud bolts. These are exposed to high loads during crane operations. In context of this thesis investigations about the most critical load concerning the stud bolt connections of loader cranes are made, to maintain a reliable dimensioning. Until now the entire axial operational force FA was taken as bolt load FS caused by a loss of residual clamp load FKR. The task is, to find out which bolt loads FS can be expected from stud bolt connections with residual clamp loads FKR. The bolt load FS consists of the preload FV and a proportion Φ of the axial working load FA. Due to the complexity of the component geometry of the stud bolt connections, the load factor Φ is obtained by means of finite element calculations. By selecting a reliable finite element model for the stud bolts and designing the area around the stud bolt connections in a very detailed way, meaningful and realistic results can be obtained. Whereas the rest of the approximately 8 m long model is kept simple by using idealisations such as beams, shells and springs to maintain a short calculation time. Because of the obtained laod factors Φ it could be identified, which one of the previously mentioned cases causes the most critical load on the different stud bolt connections. The analysed approach yields, that the loads for the statical dimensioning so far were partly asumed to low, while the fatigue calculations were held to strict. Load measurements strain gauges are conducted with loader cranes mounted on real vehicles simultaneously to the finite element simulations. The same positions and motions as in the simulations are ran through, to get similar results. The values of the measurements are compared to the analytical calculations and the finite element simulations. Despite the differences between the FE-model and the measurement setup the deviation of the loads and the load factors Φ is relatively small. The gained discoveries from the investigations enter the procedure of the stud bolt dimensioning and will lead to a better understanding of the behaviour. Furthermore, the insights enable future improvements of stud bolt connections between loader cranes and trucks.
Translated title of the contributionAnalysis of load factors from stud bolt connections for loader cranes
Original languageGerman
QualificationDipl.-Ing.
Awarding Institution
  • Montanuniversität
Supervisors/Advisors
  • Haubenhofer, Martin, Supervisor (external), External person
  • Prenner, Michael, Co-Supervisor (internal)
  • Sifferlinger, Nikolaus August, Supervisor (internal)
Publication statusPublished - 2020

Bibliographical note

embargoed until 27-03-2025

Keywords

  • load factor
  • finite elements
  • loader crane
  • stud bolt connection

Cite this