Present modeling algorithm for large-sized revolving parts’ camber can not ensure the smoothness, so a new modeling algorithm based on NURBS Curve was proposed in this study. In detail, the new modeling algorithm is as following: Firstly transfer these discrete points, which are measured along the part’s axial lead by equal distant, into a weighting unity sequence. Secondly filter this sequence by wavelet de-noising algorithm. Thirdly replace the discrete points’ amplitudes by the corresponding weights of filtered sequence, thus yield a group of new discrete points. Lastly calculate the control vertexes and weighting factors by local rational interpolation algorithm, and construct a spatial NURBS Curve through the new discrete points to obtain the model of large-sized revolving parts’ camber. It was experimentally confirmed that this model can represent drilling stem’s camber smoothly and improve its pressure straightening precision.

The fuzzy allowable intervals of the deflection, the vibration frequency and the fatigue strength of the shaft fixing grinding wheel are proposed in present paper based fuzzy set theory. According to fuzzy probability theory, the fuzzy reliability model of the rigidity, the fuzzy reliability model of the vibration and the fuzzy reliability model of the fatigue for the shaft fixing grinding wheel in internal grinding are given. The method is put into real example.

Rolling cutter curve-edge is a complex spatial curve. This paper states the present method of tool radius compensation for grinding it by 4-axis gang control grinding center, analyzes the existence of processing error due to this method, and proves the error can not be neglected. To avoid the error, a new method of tool radius compensation based on vector decoupling is raised. From a comparative experiment, it shows that the new method can promote processing precision and enlarge work-life of rolling cutter evidently.