增压中冷柴油机缸套预紧变形影响因素研究

STUDY ON INFLUENCING FACTORS TO THE CYLINDER LINER PRE-TIGHTENING DEFORMATION OF TURBOCHARGED INTER-COOLED DIESEL ENGINE

基于弹性力学理论与接触对方法,建立了四缸增压中冷柴油机的机体-缸盖-缸套的装配耦合模型,在预紧工况下研究了机体刚度、螺栓预紧力大小、缸盖螺栓沉头孔深度、缸套轴肩定位凸台的角度以及螺栓啮合长度等因素对缸套变形的影响。研究表明:四个缸的缸套变形不均匀,其中1、4缸缸套变形相对于2、3缸缸套变形较大;机体改进后,刚度提高,缸套径向变形量和扭曲度减小;螺栓预紧力越大,缸套变形越大;缸盖螺栓沉头孔深度越接近缸套轴肩定位凸台深度,缸套变形越大;缸套轴肩定位凸台的角度为20'时,缸套的变形相对较小;缸盖螺栓啮合长度对缸套的径向变形影响较小。

In this paper,the cylinder body-cylinder head-cylinder liner assembly coupled model is established based on the theory of elasticity and the method of contact. The cylinder liner deformation characteristics and the factors causing the deformation are studied under the preloaded cases. The results show that the four liners deformation is uneven and the first and the fourth cylinder liner are larger than the second and the third cylinder liner deformation. After optimizing the cylinder block,the cylinder liners radial distortion and deformation have decreased. With the bolt preload forces increasing,the cylinder liners deformation has increased. The closer cylinder head bolt counter bore depth is to the height of the cylinder convex shoulder,the greater the liners deformation is. When the cylinder convex shoulder angle is set to 20＇,the liners deformation is relatively small.The length of action of cylinder head bolts has less influence on the radial deformation of cylinder liners.