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The automotive industry seeks for lighter components in every new project. Due to strict regulations in CO2 emission and fuel consumption, design engineers are always dealing with huge challenges to manage weight reduction without structural damage for the application and manufacturing processes improvements. The drum brake system is commonly used in compact cars. This system uses two pins and two flat plates to fasten the brake shoe in the drum. A new geometry of anchor pins may contribute to achieve strict targets such as weight reduction, enhance the structural performance and also bring benefits for manufacturing processes. This work presents a new design of a lightweight drum brake anchor pin, which may contribute to the mass reduction through structural, fatigue and metal forming process simulation.

The main characteristics required when fastening racing cars wheel are the resistance to self-loosening plus high-speed to assembling and disassembling of the wheel. To attend these two contradictory characteristics, it is necessary to develop differentiated fastening solutions. This work presents a new concept of fastening central wheel nuts for racing cars with improved fastening efficiency regard safety and assembly speed in comparison to the current fastening. The new wheel nut was designed and validated through analytical and FEM analysis as well as real tests.

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.

CO₂ emission reduction through weight saving remains a huge challenge for all automotive components. When it comes to gears, the state of the art shows low potential of weight reduction due to the trade-off between mass optimization and manufacturing process. Gears are usually forged followed or not by teeth cutting operation. Current presses must operate with a minimum distance between punch and die, due to the elasticity of the equipment, in order to avoid tool failure when it operates with no working piece. Also, the press force is determined by this gap, in cases that some flash is formed during forging, and a minimum flash is required for a forgeable part using the available press. This issue constrains the minimum wall thickness of a final product, for instance, the body of an automotive gear.

The guarantee of fastening on assembled joint is still a challenge for the designers, especially regarding the torque loss and consequent loosening of the fastening elements. Among the main reasons of accidents caused by the loosening of these elements, there is the incorrect way to apply the torque on the assembly line (too high or too low) and the possibility of jeopardizing the joint fastening due to vibration acting on the system. This paper presents a solution of fastening where the resistance of the joint loosening is given by the simultaneous application of tensile effort and prevailing torque on the elastic field of the component, which decreases the possibility of self-loosening.

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.

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.