Determination of Bolt Forces and Normal Contact Pressure Between Elements in the System with Many Bolts for its Assembly Conditions

Abstract

The paper put forward a thesis that modelling dissymmetric non-linear multi-bolted connections as a system is possible. Modelling of the systems composed of four subsystems on the assembly state was presented. These subsystems included: a couple of joined elements (a flange and a support), a contact layer between them, and bolts. The physical model of the system was described considering the tightening of bolts according to a specific sequence. In this model: the flange and the support were built using spatial finite elements, the contact layer was formed as the non-linear Winkler model, and the bolts were replaced with simplified models made of flexible beams. The calculation model which can be applied to determine the changes in bolt forces, as well as in the normal contact pressure between the joined elements during the tightening of the system and at its end, was presented. The results of sample calculations for the selected multi-bolted system were shown.

Health assessment of a multi-bolted connection due to removing selected bolts

“…However, in order to make the research universal, it was performed for the case of asymmetric multi-bolted connection. The research is an extension of the paper [45] and will be used to validate the modelling method of the tightening process of arbitrary multi-bolted connections presented in [59,60].…”

Smart Tightening Development for Aeronautical Bolted Assemblies in an Industry 4.0

“…Controlling the preload within the bolted assembly can be beneficial for the integrity of the aircraft [1,2] but this tool developed for an industry 4.0 which is geolocated and able to feed a dynamic database can also be an advantage for quality control and maintenance [3]. However, the preload is a very dispersive variable [4] and is difficult to control in production with current clamping tools [5]. One of the objectives is to optimize the tightening instructions that meet aeronautical requirements, in an uncertain environment [6].…”

Finite Element Modelling of a Pair of Flexible Elements Contact Preloaded and Externally Loaded with an Arbitrary Force

“…− models of the joint, in which the contact layer between the joined elements is not taken into consideration [1], − linear contact models with constant values of the contact stiffness coefficients over the entire nominal contact surface, commonly available in commercial finite element analysis systems [9,10,12,20,21,24,31,33,38,42], − non-linear contact models [5,7,13,51]. In the above-mentioned models, the possibility of taking into account the variable contact stiffness coefficients for each of the contact elements on the contact surface is not considered, which would be useful in the case of the contact analysis of the elements joined in a connection model with the experimentally defined stiffness characteristics of the contact layer between them [16]. In this paper, a method of modelling of the contact layer, by means of which it is possible to model the elastic properties of individual elements of the layer, is presented.…”