Research On No Bumping Path Planning For Large Integral Impeller Five-Axis Plunge Milling

Centrifugal compressors are widely used in aerospace,petrochemical,natural gas and other industries,and are the core equipment of the national basic industry.The integral impeller is the core component of the centrifugal compressor,and the processing of the semi-open impeller is representative.The low efficiency of semi-opening integrated impellers is currently the current status quo.The five-axis plunge-milling impeller flow path is currently a more efficient machining method,but almost no discussion of the cutter bumping phenomenon in five-axis plunge milling.In this paper,the trajectory planning problem of the five-axis plunge milling of the semi-opening integrated impeller flow path is studied.A trajectory planning method of "double row plunge milling" is given,which can improve the machining efficiency by reducing the number of cutter axes.The cutter bumping recognition model of five-axis plunge milling of impeller is constructed,and a cutter bumping elimination method for fiveaxis plunge milling of impeller flow path is proposed.It can eliminate the cutter bumping of the existing five-axis plunge machining path of impeller flow channel.Verify the effectiveness of the method through simulation and actual machining.The main contents of this paper are as follows:(1)The idea of a semi-open integral impeller construction model is given.The mathematical cutter used in the modeling process are introduced: the inverse calculation and interpolation of the B-spline curve,the ruled surface blade and the rotation matrix,and the methods and principles used in the modeling process are deduced and analyzed.Constructed a model of a semi-open integral impeller.(2)Based on the "double row slotting" five-axis plunge milling process,the machining path planning of the impeller flow path is carried out.According to the width of the flow channel,the machining area is divided,and the milling cutters of different diameters are determined for different machining regions.The straight-grained blades are normally biased in the flow path,and the obtained offset surface bus bar family determines the cutters axis,and the cutter is lifted along its axis.After the cutter is gradually approached to the hub surface method to obtain the cutter position.A five-axis plunge-cutting trajectory with no interference in the impeller flow path is obtained.The trajectory of the impeller flow path for five-axis plunge milling is automatically planned,and the APT file recognized by the processing software can be generated.(3)Analysis of the cause of the plunge milling cutter bumping in the five-axis plunge milling process.The position of the plunge milling cutter bumping cutter in the machining path is judged by the relative positional relationship of the bottom circle of two adjacent plunge milling cutters,and the recognition model of the five-axis plunge milling process is established.Write the impeller five-axis plunge-cutting cutter recognition program,which can read the machining path file and determine the position where the plunge milling cutter bumping phenomenon occurs.(4)Write the impeller five-axis plunge-cutting cutter recognition program,which can read the machining path file and determine the position where the plunge milling cutter bumping phenomenon occurs.A method for eliminating the phenomenon of impeller five-axis plunge milling cutter is proposed.The impeller five-axis plunge milling cutter elimination program is programmed.The machining path file can be read and the cutter bumping can be removed.Finally,the impeller flow path of no bumping is obtained by five-axis plunge milling.(5)Simulation and actual machining of cutter path without blade cutter for five-axis plunge milling of impeller flow path,Analysis of the flank surface at the bottom of the impeller flow path after processing,Verify the effectiveness of the identification model and elimination method of the impeller five-axis plunge milling cutter.