汽轮机静叶片内背弧型线模型构建

The Reconstruction of Profile Line Model for the Steam Turbine Static Blade’s Lnner and Back Curved Surface

汽轮机静叶片装配内背弧型面的加工是汽轮机静叶片关键工序之一。针对汽轮机静叶片装配内背弧型面的型线结构与加工特点,应用NURBS曲线的数学原理和积累弦长法反求型线设计的三要素(控制顶点、节点矢量、权因子),在保证静叶片内背弧型线的参数化设计条件下,使加工的质量和效率不受环境的影响,在满足加工精度和表面粗糙度的同时,通过参数型线法精确构建了静叶片装配内外背弧型线模型,为型线的拟合、拟合型线的算法、拟合型线误差的研究提供理论基础。

The back curved surface machining of the steam turbine static blade assembly is one of the key processes of the steam turbine static blade.According to the structure and processing characteristics of steam turbine static blade assembly back curved surface’s profile line,using the mathematical principles of the application of NURBS curves and the accumulated chord length parameterization reverse,it can calculate the three key elements of the blade’s surface line,which are control points,knot vectors and weights.Then it makes the quality and efficiency of CNC machining from the environment,so that it can ensure the requirements of the machined part accuracy and surface roughness requirements,then using the parameters of line principles to reconstruct the static blade assembly back curved surface’s profile line accurately,it provides a theoretical basis for curve fitting,the algorithm of curve fitting,and the research on the curve fitting error.