柴油机过盈装配连杆衬套孔径收缩量的仿真分析-机械设计及理论专业论文 word格式.docx

The Simulation on Pore diameter Shrinkage of Connecting rod bushing under interference fit in Diesel engine
Abstract
The size of the fitting clearance depends on the design of connecting rod bushings aperture. If the clearance is too small, piston pin activities will be not flexible, and even killed. But is easy to produce taps and the noise with a large clearance, and it also can cause the bushing damaged or a deformation of connecting rod bending and twisting. Appropriate clearances can form oil film and plenty bearing pressure, this play a role about lubricating bearings and carrying weight. After the bushing was pressed into the connecting rod small end, it will be affected by radial stress, and a certain amount of shrinkage deformation will be produced in the hole. It will make changed on the fitting clearance between bushings hole and piston pin. The result is that it changed the original clearance, and even cause a difficult assembly. Only to reaming or repair blow can get the required hole tolerances and solve the assembly inconvenient questions. In order to free the scraped program, and improve work efficiency, this topic using elastic deformation theory to proceed theoretical analysis and fem simulation analysis about the shrinkage deformation condition of the bushings aperture. The mainly research contents of this paper are as follows:
On the basis of the theory of elastic deformation, the Aperture shrinkage under Press fits over surplus is calculated through theory. The actual aperture dimensions tolerance zone has been fixed, Aperture shrinkage and work clearance are analyzed and calculated under work surplus.
The influence on some related parameters of the aperture contraction such as material elastic modulus, structure size of bushing and the magnitude of interference between connecting rod small head and bushing are researched.
The situation of Aperture shrinkage are analyzed by using the finite element software simulation ANSYS. These situation