Study On Vibration Of The Circular Saw In The Stone Sawing Process

Based on the analysis on the research status of transverse vibration of the circularsaw and the existing problem, theoretical and experimental study on transversevibration of the circular saw has been conducted. The main work of this thesis can besummarized as follows:1. The measurement method for transverse vibration of circular saw in sawing ofstone has been studied. In order to measure the transverse absolute vibration, threeways to remove vibration from sensor mounting reference point have been proposedand compared with each other according to experimental results.2. Theoretical models and experimental studies on transverse vibration of circularsaw in sawing of stone have been conducted. Features of transverse vibration signalshave been analyzed in time and frequency domain respectively. The influence ofsawing parameters on transverse vibration of circular saw and the relationshipbetween transverse vibration and axial force have been studied. Analytical solutionshave been compared with experimental results.3. The process of granite sawing by circular saw has been simulated using softwareof ANSYS/LS-DYNA. Transverse vibration characteristics of circular saw in idlingand sawing states have been analyzed. Then, transverse vibration of circular saw withradial slots has been studied. And the number of radial slots effecting on transversevibration has been also discussed.Through experimental study and theoretical analysis, the following achievementsand conclusions can be obtained:1. In terms of the motion characteristics of stone sawing machine, in order tomeasure the transverse absolute vibration of circular saw in the sawing process, usingnon-contact measurement method can’t solve the vibration problem caused by sensormounting reference point. Another method has been adopted by using strain gagesstuck on the circular saw. Strain signals have been measured online by a developed wireless sensor measuring system, which can realize the reliable measurement oftransverse absolute vibration of circular saw in stone sawing process.2. According to the granite sawing experiment, we found that the axial deformationand axial vibration of the circular saw increase with rotating speed in idling state. Infrequency domain, transverse vibration shows as nonlinear vibration at higher idlingrotating speed and weakly nonlinear during the stone sawing process.3. The experiments results also show that axial deformation of circular sawincreases with the depth of cut and the feed speed, and decreases with the increasingrotating speed. Axial vibration increases with the feed speed and the rotating speed,and decreases with the increasing depth of cut.4. In the experiment, we found that transverse vibration and axial deformationfeatured obvious periodicity. The period is equal to that of circular saw. But theperiodicity of axial vibration is relatively weak.5. When sawing granites with different parameters combinations, there is anear-linear relationship between axial deformation of the circular saw and axial forceon it. In kerf forming process, the change tendency of axial deformation and axialforce is similar.6. Using the bending theory of small deformation for thin elastic plate，circular sawis simplified to a disk clamped on center and freed on edge. The transverse vibrationpolar equation of circular saw under the concentrated axial force has been deduced.7. The results of axial deformation in a period from experiment have beencompared with those from analytical model calculation. The similar results haveverified the correctness of the established analytical model.8. Through the FEM analysis, it has been found that in the granite sawing process,larger axial deformation of circular saw happens near the sawing arc zone. The resultsindicate that axial deformation of circular saw is mainly affected by constraint of thesaw kerf. In a cycle of the circular saw, the tendency of transverse vibration given byFEM simulation is similar to that of axial deformation by analysis and experiment.9. Axial deformation has been reduced after incision of equally spaced radial slotson the steel core. The maximum axial deformation of the circular saw decreases withincreasing numbers of slot. But the decreasing range is small.