One of the most popular machine elements, in terms of its operational background, it is a simple slope. Most of the machines contain it, everybody uses it. Even though no other joint type has been researched so widely, engineers can only estimate the performance of a bolted joint, due to-among others- the endless number of practical, non-textbook cases such as: bolts stressed to the yield point, pretension in aluminium, setting on paint films, etc. When we analyse the strength of the bolting, we have to take into consideration more parameters at the same time, and it is not easy to find our way among the relevant standards, recommendations and dimensioning specifications (e.g. VDI2230 see our later blog posts) in light of the field experiences. Finite element analysis is not always necessary to assess a bolt connection, but it might be helpful to define the loading of the bolt and estimate its safety and utility. In the following posts we discuss some topics about bolted joints and highlight some factors, which define (being unclear to most of us) the behaviour of a certain joint.