| CNC vertical lathe is an important machine tool in modern machine. Multi-functionNC vertical lathe is more adapted to the market demand. The multi-function NC verticallathe can complete the compound processing of a variety of processes in one clamping,which achieve the function of multipurpose and improve the production efficiency ofthe machine tool. As a manufacturing power, there is still a big gap between theinternational level and our country in the field of design of manufacturing equipment.Domestic structure design for machine tool is based on static performance calculationand traditional analogy method, which makes some structure of NC machine toolunreasonable, and comes to the issue such as structure’s high self-weight and the poordynamic performance. Taking CK5250DG NC vertical lathe as the research object, thisthesis makes study of the vertical lathe structure performance from the two aspects ofsimulation and experiment. This thesis also makes structure optimization anddeformation compensation for the column and beam which are the key components ofthe vertical lathe with the dynamic optimization design principles based on thesensitivity analysis, which achieves the purpose for the light-weight bed and gooddynamic performance in the condition of meeting the stiffness and strength.Centering on the CK5250DG performance analysis of CNC vertical lathe, this thesisdoes the study from several aspects, including:1.This thesis built the solid model of the CK5250DG NC vertical lathe with the3dmodeling software SolidWorks, and then achieved the finite element model of theCK5250DG NC vertical lathe machine with introducing transformation format into thefinite element analysis software ANSYS and pre-treatment process of ANSYS.2.This thesis conducted the simulation of the CK5250DG NC vertical lathe under theworst working conditions. This thesis achieved the stress and strain distribution and thefirst five natural frequency and vibration mode using the statics analysis and modalanalysis respectively. This thesis conducted the analysis of modal matching to each partof the CK5250DG NC vertical lathe to verify the rationality of other structures’ designin addition to the column and beam. Then this thesis concluded that the parts withintensive modal structure will influence the static characteristics of the machine, andthis structure should be modified or deleted from the machine, such as the top beam ofCK5250DG NC vertical lathe.3.AS the key components of CK5250DG NC vertical lathe, experiment research of beam is conducted. On the one hand, the conclusion of simulation analysis is verified,on the other hand, the modal parameters of CK5250DG NC vertical lathe beam isdetermined. This thesis systematically introduced the modal experimental researchmethods, procedures and matters needing attention, and verified the credibility of themodal experiment results by using curve fitting and MAC histogram. In the mean time,this thesis provided the basis to compensate the deformation and manufacturing ofbeam.4.This thesis introduced the theory of structure optimization design and the principleof dynamic design and set the column the optimization object. This thesis takes threemain parameters of the column which are height of wall thickness, steel thickness, andthe height of the ribs to conduct the sensitivity analysis, and achieved the influencedegree that the three parameters made on the first-order natural frequency of the columnwhich find the optimal parameter combination to optimize the column. The optimizedcolumn realized the aim of the lightweight design on the basis of meeting therequirements of the performance of the CK5250DG NC vertical lathe machine. Thisthesis compensated the deformation and manufacturing of beam and the product testingresults show that straightness of datum plane A is0.016/1000, and the total length is notmore than0.028; Parallelism that Datum H relative to datum B is0.017. The machineperformance of CK5250DG NC vertical lathe is good after assembly debugging, whichhas reached the advanced level. |
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