Strength Calculation Analysis And Experimental Study Of Diesel Engine Connecting Rod

As one of the important components of the diesel engine, the connecting rod bears thealternating load of stretching, compression, so working conditions on it are very complex.Besides, the connecting rod’s reliability and life span determines the engine’s reliability andlife span to a great extent, so it is required that the connecting rod possess sufficient fatiguestrength. With constant development of computer software and hardware and the finiteelement technique, the large, general purpose finite element technology has become the firstchoice for product development and structural design optimizing in engineering technologyfield. In comparison with advanced static sophisticated finite element analysis technologywith higher and higher computational accuracy, the dynamic response analysis which hasbecome the hot issue in the last few years has promoted constant development of connectingrod FEA from static state to dynamic state.In this paper, TBD620model diesel engine connecting rod was selected as our researchsubject. Firstly, a complex three dimensional model of linkage assembly was constructedusing the strong modeling software PRO/E, which comprises such parts as piston pin,connecting rod bushing and bearing shell. Then the model was introduced into the FEAsoftware of ABAQUS by STEP format for the sophisticated3D contact FEA. By consideringthe contact between every units and assembly pretightening force, The three major connectingrod operating modes such as the assembly condition, the maximum compression conditionand maximum inertia force condition were analyzed from traditional statics aspect. Fromabove analysis, The stress distribution and transformation situation of the linkage under everyoperating mode were determined so as to verify the connecting rod’s reliability and to checkit’s fatigue strength with safety factor method. Meanwhile, a connecting rod piston model wasadded into the above3D model and the load was directly applied on the top of it withoutsimplification. From the comparision and analysis of the computation under differentboundary conditions, the rationality of the traditional statics stress simplification was proved.Based on connecting rod static stretching and compression test by electro motive strainmethod, we obtained the actual strss-strain of the connecting rod under all load and testifiedthe accuracy of3D contact FEA for the connecting rod by the comparision and analysis of thefinite element simulation results as well as provided some technique references for dieselengine connecting rod static strength test.Then, the connecting rod’s transient response was explored according to Dynamicstheory and the detailed steps were as follows:1) obtain connecting rod transient stress by creating crank connecting rod multi-body analysis model with advantages of ABAQUS innonlinear filed, and compare it to the stress under static state to from analysis;2) determinethe vibration performance of the connecting rod by model analysis theory.