Performance Analysis And Experimental Study Of Cast Iron Cranksshaft Of 4K2 Engine

The gasoline engine is the core component of the gasoline car,which provides power for the car to run.As the core component of engine power,crankshaft bears the exciting force generated by cylinder and conducted by connecting rod,and outputs it as torque to drive other relevant parts of engine to work.The crankshaft material has a direct impact on the service performance and life of the engine,so in the engine design,it is necessary to ensure that the crankshaft does not allow cracks and other quality problems in the whole life cycle of the automobile engine.Under the condition of ensuring the manufacturing quality,how to save the cost from the design is also the goal that the design process needs to consider.Using nodular cast iron crankshaft instead of alloy steel crankshaft,under the premise of ensuring performance,can save cost 1/3 ?1/2,so as to achieve the purpose of reducing cost and increasing efficiency.Engine crankshaft system refers to the parts and components that interact with the movement of crankshaft connection during engine operation,mainly including crankshaft,connecting rod,flywheel,and crankshaft damping pulley,etc.When the structural design and machining process of engine crankshaft are proved to be correct and reasonable by actual installation and application,the change of material will affect the parameters such as weight,stiffness and moment of inertia of crankshaft.In the process of crankshaft dynamics analysis,the changes of weight,stiffness,moment of inertia and other parameters will result in the changes of bearing stress,torsional vibration and strength.Due to the complexity of motion and force analysis of the crankshaft system,considering the computing capacity of the computer,only one dimensional simulation analysis can be done on the crankshaft as a whole,and then three dimensional simulation analysis on the crankshaft can get the accurate conclusion of local position?In this paper,AVL EXCITE DESIGNER is used to calculate the torsional vibration of the crankshaft system and the crankshaft bearing meet the design requirements,but the fatigue strength of the crankshaft fillet does not meet the design requirements.Through AVL EXCITE PU,3D simulation model was established and combined with FEMFAT fatigue analysis software to find the precise position of crankshaft fillet fatigue strength that did not meet the design requirements,as well as the accurate parameters of crankshaft fillet fatigue strength.In view of the safety factor of crankshaft fillet fatigue strength can not meet the design requirements,an improvement scheme is put forward,and the improved results are verified again by software simulation.Through proof,the crankshaft fatigue strength can be improved by using the crankshaft fillet sinking rolling process,and the results can meet the design requirements.After the design of engine ductile cast iron crankshaft is completed,the crankshaft bending fatigue test and engine comprehensive endurance test are carried out to verify whether the ductile cast iron crankshaft meets the design requirements and actual installation requirements.The purpose of this paper is to solve the car engine using alternative alloy nodular cast iron crankshaft,design process and the validation process needs to pay attention to and solve the practical problems,in the design of engine parts manufacturing process and engineering problems of the practical application process,At the same time,this paper verifies the rationality of the design and use process of the ductile cast iron crankshaft replacing the alloy steel crankshaft.