Research On Tools System Of Double-sided Grinding And Polishing For Blade And Experiment

In recent years, with the rapid development of the industry, the energy demandwas increasing. The performance of the energy power equipment requirements shouldbe improved. The common Energy power equipment was turbine, water turbine, andaero-engine. Blade is one of the important parts in those equipments. The workingperformance of turbine is direct affected by the material characteristics and the qualityof the blade. The materials of the blade should have a lot of characteristics, such ashigh mechanical behavior and good stability. The difficult-to-machine materials werechosen, such as1Cr13,2Cr13. The manufacturing process of blades can be dividedinto three steps: the production of blanks, rough turning, and accurate grinding. Theaccurate grinding is a important step for the blade manufacturing, which can increasethe surface roughness and amend the surface precision.Base on the specialty of the blade machining process, the double-sided grindingand polishing machine for blade finishing were developed by the Institute ofintelligent precision manufacturing of Jilin University. The machine can finish thedouble-sided surface of the blade at the same time. So the machine had highproductivity. In the paper, the double-sided grinding and polishing machine prototypefor blade finishing was as the carrier. According to the characteristics of the machinetool movement, size restrictions, the material properties and the surface morphologyof the blade, the contact wheel exchangeable tool system of abrasive belt grinding andpolishing were designed, and polishing experiments were preceded.Two sets of abrasive belt grinding and polishing tools system were beendesigned and developed, the contact wheel exchangeable tool system and theconstant force grinding and polishing tool system.The contact wheel exchangeable tool system was designed based on the processing characteristics of blade shape and size. Because the variation range of theblade section curvature is bigger, the form of multiple contact wheel rotation was used.The corresponding contact wheel can be selected automatically in polishing differentregions to guarantee line contact between the contact wheel and the blade surface. Thecontact wheel exchangeable grinding and polishing tool system can well ensuresurface profile of the blade. The basis of the design and selection of parts wescomprehensively analysed. and the CATIA three-dimensional model was established,virtual assembly and interference inspection proved that the design of contact wheelexchangeable grinding and polishing tool system’s structure is reasonable.In order to realize the blade precision polishing, the grinding amounts at eachmachining trajectory point needed to be ensured. There were two important factorsinfluencing grinding quantity: the grinding speed and the force between the blade andabrasive belt. According to these two factors, on the basis of the original structure ofcontact wheel exchangeable grinding and polishing tool system, designed anddeveloped a set of constant force grinding and polishing tool system. Innovation pointwas that it has a structure of decoupled forces, it can decouple the grinding pressure,can realize the precise control of the grinding pressure without depending on theadjustment of the machine. The CATIA three-dimensional model is presented, virtualassembly and interference inspection proved the tool system structure was reasonable.Analysis of constant force grinding and polishing tool system by ANSYS Workbenchwas did, static characteristic and vibration characteristics, and got the deformation andstress and six order vibration mode of the tool system.A stable, accurate and reliable control system was established to achieve thereliable working of the tool system. According to the requirement of these two toolsystems movement, the way of PC+motion control card, half closed loop controlsystem was adopted in the paper. Determined the overall scheme of the control system,and established the control system hardware connection.Finally, a lot of experiments under different process parameters were conductedby using the contact wheel exchangeable tool system and the constant force grindingand polishing tool system. By the experiment results, obtained the influence law of process parameters on the polishing quality. Compare the two tools system’sexperiment results, showed that constant force grinding and polishing tool system’sprocessing effect is better. Therefore, get the polishing pressure constant controlplayed a key role on the polishing quality, it laid a solid foundation for subsequentpolishing processing equipment research and development.