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Research on the Sensitivity of Infecting the Quality of the Surface in Super-high Speed Point Grinding

Author: LiuYueMing
Tutor: GongYaDong
School: Northeastern University
Course: Mechanical Manufacturing and Automation
Keywords: super high speed point-grinding designing of wheel simulation grinding force
CLC: TG580.6
Type: Master's thesis
Year: 2009
Downloads: 72
Quote: 0
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Abstract

Super-high speed point grinding is more advanced and more efficiency as a method super-high speed grinding, which integrates CNC technology, the technology of CBN wheel and super-high speed grinding. The technology is widely used in machining shafts, which is applied in the fields of machine tools, car manufacturing and tool manufacturing, but this technology is belonged to underway developing. The advantages of this technology are bringing low grinding force and low grinding temperature compared to common grinding, but the research on the mechanism and the controlling of grinding quality is rare in domestic and foreign countries. Some domestic factories of car manufacturing introduce into this technology, which is brought with QUICKPOINT5000. But the core of technology isn’t mastered by domestic enterprises, as result of adopting the primary programs only, which restricts the applied rang and the exploitation of technology. It is necessary to research the theories and the applications of super-high speed point grinding deeply and master the advanced technologies for improving the equipment manufacturing technologies.In super-high speed point grinding, a thinner(4to6mm) super abrasive (CBN or diamond) grinding wheel that the speed between90-160m/s is used. The basic working principle of super-high speed point grinding is:there are angles between the axis of workpiece and the axis of wheel in two directions, both in the horizontal plane and in the vertical plane. The purpose is making the contact area of the wheel and the workpiece being only a point. The wheel used in it is different with the common wheel, which owns the angle of coarse machining. In conclusion, the details of the study are as following:(1)The function, sort trait and development of the high and super-high speed grinding technology are systematically summarized, the super-high speed point grinding was emphasized as a key content especially. The intention and significance of the topic research are also introduced.(2)According to the specific of the new type wheel, the functions of the field of coarse grinding and finished grinding are introduced respectively, introducing the function of the angle between the wheel shaft and the workpiece shaft, calculating different redundant material column wiped off by different grinding area, getting the equivalent diameter and velocity in coarse grinding area, acquiring the length of contacting arc. A simulation model using explicit finite element Abaqus is developed to investigate the residual stress’s distribution in a machined layer while different machining velocity and different depth in machined surface, which provide the theory to achieve high precision machining in super-high speed point grinding.(3)Adopting the finite element model of axisymmetric, analyzing the distribution of round stress and radial stress in the wheel body and the radial displacement while high rotating in theory. The distributions of stress and displacement from different section of wheel body are got while the speed is150m/s through the simulation of ABAQUS to confirm the shape and material of the wheel body, analyzing the relation between the quality of machined surface and grain, granularity, bond and the dimension of the layer of CBN.(4)Design the experiment to measure the tangent force and normal force while common cylindrical grinding and point grinding, according to the formula of grinding force from common cylindrical, introduce the expression of point grinding force, compare the effect for grinding force from a in theory, which attained from finial for measuring grinding force, analyzing the origin of error.(5)Summarize the conclusions from the paper and give the rational suggestions for further research.

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CLC: > Industrial Technology > Metallurgy and Metal Craft > Metal cutting and machine tools > Grinding and grinding machine > General issues > Grinding process
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