High-Speed CNC Grinding Process Optimization of Non-Circular Rotary Parts Based on Particle Swarm Optimization

As for the high-speed CNC grinding process for non-circular rotary parts with a large rate of lift change (such as camshaft of automotive engine), the acceleration of grinding wheel often has a direct impact on the contour grinding precision of the workpiece due to the large acceleration of movement between of the workpiece and the grinding wheel produced from CNC grinding interpolation. Researches show that solving this problem is an important way to improve the precision of high-speed CNC grinding for non-circular rotary parts. In this paper, a high-speed CNC grinding process control and optimization method is presented for non-circular rotary parts based on acceleration interpolation movement. The negative inﬂuence of the problem about high acceleration can be reduced eﬀectively and the precision of high-speed CNC grinding for non-circular rotary parts can be improved greatly by the proposed method. Additionally, the simulation shows that the optimization of grinding parameters forgrinding process has a good performance.

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Study on Edge Contact Area and Surface Integrity of Workpiece in Point Grinding Process

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.407-408.577 ◽

2009 ◽

Vol 407-408 ◽

pp. 577-581

Author(s):

Shi Chao Xiu ◽

Zhi Jie Geng ◽

Guang Qi Cai

Keyword(s):

Surface Integrity ◽

Contact Area ◽

High Speed ◽

Ground Surface ◽

Depth Of Cut ◽

Grinding Wheel ◽

Grinding Process ◽

Edge Contact ◽

Cylindrical Grinding ◽

Theoretic Foundations

During cylindrical grinding process, the geometric configuration and size of the edge contact area between the grinding wheel and workpiece have the heavy effects on the workpiece surface integrity. In consideration of the differences between the point grinding and the conventional high speed cylindrical grinding, the geometric and mathematic models of the edge contact area in point grinding were established. Based on the models, the numerical simulation for the edge contact area was performed. By means of the point grinding experiment, the effect mechanism of the edge contact area on the ground surface integrity was investigated. These will offer the applied theoretic foundations for optimizing the point grinding angles, depth of cut, wheel and workpiece speed, geometrical configuration and size of CBN wheel and some other grinding parameters in point grinding process.

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Study on Effect of Grinding Fluid Supply Parameters on Surface Integrity in Quick-Point Grinding for Green Manufacturing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.53-54.209 ◽

2008 ◽

Vol 53-54 ◽

pp. 209-214 ◽

Cited By ~ 1

Author(s):

Shi Chao Xiu ◽

Ya Dong Gong ◽

Guang Qi Cai

Keyword(s):

Surface Integrity ◽

High Speed ◽

Point Contact ◽

Green Manufacturing ◽

Grinding Wheel ◽

Grinding Process ◽

Grinding Fluid ◽

Fluid Supply ◽

High Speed Grinding ◽

Grinding Power

In high and super-high speed grinding process, there is an airflow layer with high speed around the circle edge of the grinding wheel that hinders the grinding fluid into contact layer, namely, the air barrier effect. The speed of airflow layer is directly proportional to the square of the wheel speed. Quick-point grinding is a new type of high and super-high speed grinding process with a point contact zone and less grinding power. The edge effect of the air barrier is weakened because the thin CBN wheel is applied in the process. By the analysis of dynamic pressure and velocity distributions in the airflow layer around the wheel edge, the mathematic models of the flow and jet pressure of grinding fluid for effective supply in the process were established and the process of optimization calculation of the jet nozzle diameter for green manufacturing was also analyzed based on the thermodynamics and the technical character of quick-point grinding process. The quick-point grinding experiment for surface integrity influenced by grinding fluid supply parameters was performed.

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Modelling and experiment of gear hob tooth profile error for relief grinding

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211017297 ◽

2021 ◽

pp. 095440542110172

Author(s):

Shuying Yang ◽

Weifang Chen ◽

Zhiqiang Wang ◽

Yanfeng Zhou

Keyword(s):

Prediction Model ◽

High Speed ◽

Tooth Profile ◽

Grinding Wheel ◽

Grinding Process ◽

Feed Speed ◽

Machining Parameters ◽

Profile Error ◽

Mechanical Coupling ◽

Axial Profile

Gear hob is an important tool that is most used in gear processing. Hob accuracy directly exerts an overwhelming influence on the quality of the processed gear. Generally, the hob tooth profile accuracy is mainly determined by relief grinding process. Studies on tooth profile errors of gear hobs caused by severe friction and cutting with the high-speed rotation of the wheel during the form grinding machining of hobs are limited. Thus, a theoretical model of the tooth profile error prediction under different machining parameters was established based on the analysis of coupling influence of high temperature and high strain rate on gear hobs in the relief grinding process. The model was completed on the basis of the dynamic explicit integral finite element method of thermo-mechanical coupling. Through the prediction model, the influence of the grinding depth ap, feed speed Vw and grinding speed Vs on the tooth profile error can be analysed. In addition, an algorithm for accurately calculate the grinding wheel axial profile by combining instantaneous envelope theory and hob normal tooth profile was proposed. The hob relief grinding experiments were carried out using the proposed grinding wheel profile algorithm. The relative error of the prediction obtained by comparing the calculation results of the prediction model with the experimental results is within 10%. Results prove the validity of the prediction model. This finding is greatly important for optimising the accuracy of hob relief grinding.

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Research on the Grinding Force of the Basin-Like Grinding Wheel in Grinding Elliptical Grooves of Outer Race

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.823.143 ◽

2013 ◽

Vol 823 ◽

pp. 143-148

Author(s):

Xiao Xue Li ◽

Jun Ming Wang ◽

Yu Qin Sun ◽

Zhen Gang Gao

Keyword(s):

High Speed ◽

Grinding Force ◽

The Other ◽

Grinding Wheel ◽

Grinding Process ◽

Feed Velocity ◽

Outer Race ◽

Abrasive Grains ◽

Other Hand

In order to calculate the grinding force of the basin-like grinding wheel in grinding outer race elliptical grooves, the thesis simplifies the grinding process as follow: the evenly distributed abrasive grains move around grinding wheel axis along an imaginary ellipse at high speed, while the imaginary ellipse moves along the trace deflected from the grinding wheel axis simultaneously. The analysis of grinding force in CVJ outer race elliptical groove grinding with basin-like grinding wheel reveals that, the grinding force will be decreased, if wheel velocity increased and feed velocity decreased. On the other hand, with the decrease of inter-grain spacing, the grinding force of basin-like grinding wheel will be increased, but the grinding force of abrasive grit will be decreased.

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Precision Grinding Process Design of Twin-Screw Compressor Rotor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.1107 ◽

2013 ◽

Vol 774-776 ◽

pp. 1107-1111

Author(s):

Yong Qiang Zhao ◽

Sheng Dun Zhao ◽

Hong Ling Hou

Keyword(s):

Process Parameters ◽

Grinding Wheel ◽

Screw Compressor ◽

Grinding Process ◽

Compressor Rotor ◽

Cnc Grinding ◽

Twin Screw ◽

Screw Rotor ◽

Working Parameters ◽

The Relationship

With the accuracy improvement of twin-screw compressor rotor machining, higher requirement of crew rotor grinded equipment and grinding process is put forward. Based the theory of screw grinding and CNC forming grinding wheel dress technology, the relationship between machine working parameters, CNC grinding wheel dressing parameters and screw rotor grinded process parameters are investigated, and the relationship between CNC grinding wheel dressing parameters and the screw rotor grinded process parameters is established, and its formulas are presented to describe the distances between grinding wheel axis and screw rotor axis. Through these formulas, the CNC wheel dressing program could be designed easily, the performance and efficiency of machine would be improved, and especially the machining quality of screw rotor would be enhanced and becomes more stability.

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Mathematical modeling of the surface roughness of the grinding wheel during straightening

Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu ◽

10.33271/nvngu/2021-1/053 ◽

2021 ◽

pp. 53-59

Author(s):

R. M. Strelchuk ◽

S. M. Trokhimchuk

Keyword(s):

Mathematical Modeling ◽

Surface Roughness ◽

High Speed ◽

Roughness Parameter ◽

Ground Surface ◽

Grinding Wheel ◽

Grinding Process ◽

Research Results ◽

Abrasive Grains ◽

Working Surface

Purpose. Research on the mechanism of influence of the straightening conditions of the grinding wheel, including the relative oscillations of the wheel and a multipoint diamond dresser, on the roughness of the ground surface and other machining results. Methodology. Straightening a grinding wheel with a multipoint diamond dresser is a process of high-speed destruction of a hard, abrasive material and its bond under the instantaneous forces, abrasive grains with a hard surface of a diamond crystal. During the grinding wheel straightening, the total component of normal forces causes correspondingly less elastic deformations in the wheel straightening tool system, which increases the accuracy of the geometric shape of the grinding wheel working surface. Findings. The research results make it possible to determine the parameters of the surface roughness of a workpiece and to find ways to control it to increase the efficiency of the grinding process. Originality. The regularities of the influence of the grinding wheel straightening conditions on the state of its working surface have been established. The paper shows that the initial arrangement of grains along the normal to the surface of the wheel is determined by its characteristics. When the abrasive grains hit the surface of the straightening tool, some of the vertices are chipped off, as a result of which the density of the grain vertices on the outer surface of the wheel increases. The straightening process was further developed in the direction of the non-uniform character of the location of the vertices of abrasive grains. The distribution of the grain position at the wheel bond depends on the straightening conditions. Since the removal of the allowance in the process of grinding is carried out by the most protruding grain vertices, then, consequently, the result of grinding will depend on their location and the conditions for the wheel straightening. Practical value. Application of the research results obtained in the work, namely, mathematical modeling of the surface roughness of the grinding wheel during straightening, makes it possible to calculate the roughness parameter of the ground surface. The work also shows that the level of chipping of the grain vertices depends on the grinding wheel straightening conditions, in particular, on the value of the axial feed of the straightening tool. In this case, lower stresses arise in the grains and the bond, and the tool works as a harder one. Straightening conditions affect the stability of the grinding wheel and its self-sharpening process in the machining zone. This determines the significant role of straightening in the results of the grinding process.

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A High-Speed Precision Bearing Internal Grinding Machine and Grinding Process

10.21203/rs.3.rs-423958/v1 ◽

2021 ◽

Author(s):

Zhou Chang ◽

Qian Jia ◽

Lai Hu

Keyword(s):

High Speed ◽

Engineering Application ◽

Grinding Wheel ◽

Grinding Process ◽

Guide Rail ◽

Precision Grinding ◽

Internal Grinding ◽

High Speed Grinding ◽

Bearing Raceway ◽

Grinding Machine

Abstract In order to meet the requirement of grade P2 bearing grinding, we designed a high-speed internal grinding machine used for bearing raceway and inner circle grinding. The machine adopts T-type layout and 4-axis NC linkage. It is supported by hydrostatic pressure and driven directly by torque motor. Besides, it is equipped with high-speed hydrostatic grinding wheel spindle of ELKA. Our design includes hydrostatic workpiece shaft, hydrostatic turntable and hydrostatic guide rail. The design of this machine can ensure the high-speed grinding process and research has good engineering application value. Finally, the designed precision grinding machine is used to grind the P2 bearing raceway with reasonable processing technology.

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Study on Balance Precision of Ultra-High Speed CBN Grinding Wheel System

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.375-376.614 ◽

2008 ◽

Vol 375-376 ◽

pp. 614-618 ◽

Cited By ~ 2

Author(s):

Shi Chao Xiu ◽

Jian Liu ◽

Chang He Li ◽

Guang Qi Cai

Keyword(s):

High Speed ◽

Dynamic Performance ◽

Grinding Wheel ◽

Grinding Process ◽

Rigid Rotor ◽

Machining Quality ◽

Ultra High Speed ◽

High Speed Grinding ◽

Cbn Grinding Wheel ◽

Grinding System

The balance precision of grinding wheel is a key technical parameter in ultra-high speed grinding process. The actual standard for the balance precision of rigid rotor is not fit for the thin ultra-high speed grinding system well. The unbalance factors affected on the ultra-high speed grinding wheel and its system were analyzed, and its effects on the machining quality in the process were also discussed. The theory and select principle of the balance precision for ultra-high speed grinding wheel system were studied. The test of dynamic performance was performed for the thin ultra-high speed CBN grinding wheel system whose structure was optimized. The groundwork to establish the standard of balance precision for thin ultra-high speed grinding system was offered.

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Study on Properties of Grinding Fluid Jet and Nozzle Position for Super-High Speed Point Grinding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.135.452 ◽

2010 ◽

Vol 135 ◽

pp. 452-457

Author(s):

Shi Chao Xiu ◽

Ji Man Luo ◽

Zhi Li Sun

Keyword(s):

Contact Area ◽

High Speed ◽

Fluid Velocity ◽

Grinding Wheel ◽

Grinding Process ◽

Pressure Balance ◽

Balance Principle ◽

Grinding Fluid ◽

High Speed Grinding ◽

Grinding Machine

Super-high speed point grinding is a new high-speed grinding technology with some excellent machining performances. In such a grinding process, there is a high-speed airflow rotating around the edge of grinding wheel which hinders the grinding fluid from injecting into the contact area and makes the fluid atomization and splash during grinding process, so as to decrease the ratio of effective grinding fluid into contact area and affect the surface integrity of workpiece. In this paper, the structure and properties of grinding fluid jet is analyzed, the velocity distribution field of the round turbulent jet is discussed theoretically and simulated. Based on the pressure balance principle, a mathematical model is established for the jet velocity at the fluid nozzle, which enables the grinding fluid to pass through the high speed airflow and enter into the contact area. According to the analysis of the grinding fluid velocity in the jet core, an engineering formula is given to calculate the position limit of nozzle during grinding process, as well as a practical design example for the high speed grinding machine is presented.

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