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High axial loads applied on conical roller bearings can lock the wheel hub after the fastener assembling. This assembly can be made, nowadays, using a castle nut plus a cotter pin or by plastic deformation of the nut to prevent its release. This procedure involves many components for the assembling, restrict its reuse, add extra costs, and provide possible failures during the assembling line or during the future maintenance. This work proposes to demonstrate the development of an efficient and easy system to mount wheel hubs on lines and later to assure maintenance without jeopardizing the efficiency and the functionality of the tapered roller bearing.

Wheel hubs typically are set in vehicles through nuts with self-locking feature to assure safety. That feature may be done by an external component like a cotter pin, a deformable element incorporated to the nut like polyamide or metallic insert or some controlled mechanical deformation applied right on nut body. Nuts with some self-locking elements are being used in order to eliminate cotter pins from the system. However, during the maintenance of vehicles, some disadvantages appear like damage in thread axle due disassembling, considering controlled mechanical deformation nuts or the replacement of nut with polyamide insert to assure self-lock featuring. This paper presents a solution to replace a fastening in a current front and rear wheel-hub for a passenger vehicle. The study is made comparing a current solution, a controlled mechanical deformed nut - stover type - from a polyamide insert nut and an innovative prevailing torque nut with incorporated washer.

Frictional contact is a recurrent theme in engineering thanks to its ubiquity on several fields of study and the fact it can not be calculated ab initio. Furthermore, it gives rise to other complex phenomena that can only be predicted with the help of numerical methods, like the Finite Element Method (FEM). However, most FEM software still use Coulomb's local model of friction to estimate friction, which may not be reliable on predicting phenomena as complicated as the object of this paper. This work aims to simulate the stick-slip phenomenon in a press-fit and to compare this simulation with laboratory tests. The work was developed based on real cases such as the development of assembled camshafts using tubes. The structural simulations were performed using linear static analysis through the use of finite element method software. Tests were done on a digital torque tester machine used for bolts and nuts. At the end of the work the results obtained in the tests are presented.

The effective length of screwed fasteners, regarding its correlation between safety assembling and production issues, has always been an open question for designers of fastening system. This work presents a real case of dimensioning one wheel nut according to theoretical and practical tests in order to guarantee a safe assembling. The objective of this study is to validate the geometric dimensioning of metric threads and their applications under real conditions.