Study On Key Technologies Of Integral-shroud Blade Diaphragm’s Parametric Design Based On Inventor

Rapid development of modern industry puts more severe challenges to today’senterprises. Product design, as an important part of enterprises’ operation process, thelength of the design cycle directly decides the competitive ability of the enterprises.The design of mechanical products mostly experience theoretical design,3D modeling,virtual assembling, engineering drawing and parts’ machining etc. From theoreticaldesign to parts’ processing, it needs to constantly adjust product parameters, whileevery change would result in the whole work’s repetition, which is an intensity laborfor designers. In addition, the products of an enterprise generally have the similarity,which means the structure is similar and size is different. This kind of similarity leadsto more redundant labor and poor efficiency during the process of designing of similarproducts. Therefore, the effective use of the existing design platform to create specificproduct design software is very important to shorten the development cycle and toimprove design efficiency. Taking integral-shroud blade diaphragm of steam turbine asexample, the paper researches the key technologies of parametric design based onAutodesk Inventor, including parametric modeling technology of parts, automaticallyvirtual assembly method of components and automatic drawing technologies ofengineering drawings, which are consistent with the appropriate parts and components.Functions of the integral-shroud blade diaphragm’s parametric design system aredivided and the relationships between each function are established. Interfacetechnology between user interface and Inventor is studied and user interfaces aredesigned. Besides, database is established as the platform to share data for all thefunctional modules.Two kinds of parametric modeling methods based on Inventor are studied, whichare editing expression and modeling by program. And on the basis of modeling byprogram method, free-form surface’s established method of blade body and3D sketchcure fitting method of blade’s shroud and hub are studied. On the aim at variablecharacteristics’ parametric design, a thought of integrating the editing expression andmodeling method is proposed, and concrete example is given. When it comes to theautomatic assembly problem, the traditional automatic assembly method which wasbased on searching feature is abandoned and a new automatic assembly method, which is based on the name, is introduced. This kind of new method improves the efficiencyof program design and implementation.On the automatically drawing technology, API function’s extension technique isstudied primarily, by which lots of functional modules are developed to meet themixed requirements of engineering drawing. Then modular thought of the map view isput forward, solving the variable characteristics’automatic drawing of mapping project.Moreover, a key technology, dimension’s back annotation, based on the existingnumerical value is proposed, which is suitable for projection view. The key technologyperfectly solves the dimension marking of projection view automatically andreasonably.Finally, the key technologies in this paper are applied to the development of theintegral-shroud blade diaphragm’s parametric design system. The experiment resultshows that the system can complete parametric modeling, automatic assembling anddrawing task, which greatly shortens the development cycle and improves the designefficiency. At the same time, it is also a successful application of computer aideddesign in mechanical design field.