Research On Functional Dimensions Of Mechanical Hole And Shaft Parts

With the improvement of measurement accuracy and mechanical accuracy, and the rapid growth of the precision requirements in Machinery manufacturing, mechanical thermal deformation has become a key factor affecting the mechanical accuracy. The degree of attention at home and abroad for the mechanical thermal deformation continues to increase. Researching mechanical thermal deformation not only on a theoretical basis, but also has profound significance in the application technology, and play an important role in scientific and engineering applications. This article is supported by two National Natural Science Foundation Project:’Mechanical Complexity Body Thermal Robustness Fundamental Research(No.51175142) and ’Coupled Modeling And Influence Research In Functional Surface Structure And Performance(No.51490660/51490661)’,made the mechanical parts in the most basic and common parts of the hollow shaft as research subjects, research its thermal deformation of accurate simulation deeply.Content of this paper includes:Firstly, the objective existence of dissimilarity of mechanical part thermal deformation is demonstrated from the view of mechanism, The atomic model of cube aluminum material at microscopic level was built and solved by using the molecular statics theory and algorithms. The objective existence and formation mechanism of dissimilarity of mechanical part thermal deformation are demonstrated, which makes up defect of demonstrating it only by macroscopic experiment and perfects the mechanical parts thermal deformation theoretical foundation, through the evolutionary computation on the thermal deformation law of aluminum ring atom model.Secondly, at the macro experiment, For Radial thermal deformation measurement of hole, shaft parts in uniform steady-state temperature field,We designed a special fixture. The fixture can meet measurement for different size parts, Significantly reduced the design time due to the different size parts requirement, improve the efficiency of the experiment.Thirdly, putting forward the mechanical shaft hole functional size theory and its engineering applications, based on the optimal thermal fit theory and mechanical thermal robust structure design, with the hollow shaft gap variation change from the different temperature. Comprehensive consider the conditions of temperature and stress loads on the shaft with the hole, in the beginning of the design, compensate dimensions and tolerances of hollow and shaft, to ensure machinery and equipment to meet the design precision and optimum performance.