The aim of my thesis is to create a procedure for the calculation of con rod stress in MBS Software. The thesis contains several parts, i.e. a short research of contemporary con rods, con rod modelling with the use of Pro/E, methodics of the finite-element con rod model preparation and model analysis in ANSYS Software, creating of virtual combustion engine template with flexible con rod and carrying out a strain hardening analysis in ADAM/Engine software. The theme of my thesis is quite demanding in the combination and the use of several computer software programmes. The thesis offers a survey of possibilities, procedures and methodics of con rod stress solutions that help to clarify the matter.

Connecting rod are found in most combustion engines and transmits thrust from the piston to the crankshaft. The connecting rod needs to withstand forces from the piston and inertia forces which results in axial tension, compression stresses and bending. Today the most common manufacturing techniques in automotive industry are drop-forging, die-casting and the Powder Metallurgy technique used is powder-forging. In this Master Thesis different connecting rod designs for a single press PM manufacturing process were created and evaluated as a part of Höganäs AB's Total Powder Metal Car project, TPMC. This paper will serve as a basis for future connecting rod projects at Höganäs AB when choosing a suitable connecting rod design. The main objective of this Master Thesis is to evaluate different designs in regards to the following: Buckling strength Fatigue life Manufacturing rating The study shows that there is evidence that a single pressed connecting rod is possible. No absolute answer of which design is the best is given in this paper since in depends on different parameters and application. For each parameter examined there are results presented and arguments for and against each design which can aid designers in future work. Suggestions of improvement on both the method and on the designs are presented in respect to the results. The improvements may potentially increase the fatigue life, buckling strength and improve manufacturability.

Diploma work is focused on computational comparison of con-rod of spark ignition four-cylinder engine with volume 1289 cubic centimeters and con-rod of spark ignition three-cylinder engine with volume 1198 cubic centimeters. 3-D models of inspected con-rods were based on real shape. Force loads effects were established after kinematic and dynamic analysis. Stress analysis was made for these force loads effects in selected cases with help of Finite element method. Two con-rods were compared by using of these results.