Virtual machining system simulator: analysis of machine tool accuracy

The coupling characteristic of the tool-holder/spindle interface in high speed NC machine has significant influence on machine tool accuracy and process stability. With the example of HSK-E63, based on nonlinear finite element method (FEM), the coupling characteristic of the tool-holder/spindle interface under high rotational speed was investigated, the influence of interference, clamping force and rotational speed on the contact stress and the sectional area of clearance were discussed in detail. The results can be used as theoretical consideration to design and optimize the high speed tool-holder/spindle interface.

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Effect of Supply Cooling Oil Temperature in Structural Cooling Channels on the Positioning Accuracy of Machine Tools

Journal of Mechanics ◽

10.1017/jmech.2019.29 ◽

2019 ◽

Vol 35 (6) ◽

pp. 887-900 ◽

Cited By ~ 2

Author(s):

K.-Y. Li ◽

W.-J. Luo ◽

M.-H. Yang ◽

X.-H. Hong ◽

S.-J. Luo ◽

...

Keyword(s):

Machine Tool ◽

Thermal Deformation ◽

Thermal Error ◽

Machining Accuracy ◽

Feed System ◽

Positioning Accuracy ◽

Cooling Channels ◽

Position Accuracy ◽

Machine Tool Accuracy ◽

Volume Method

ABSTRACTIn this study, the thermal deformation of a machine tool structure due to the heat generated during operation was analyzed, and embedded cooling channels were applied to exchange the heat generated during the operation to achieve thermal error suppression. Then, the finite volume method was used to simulate the effect of cooling oil temperature on thermal deformation, and the effect of thermal suppression was experimentally studied using a feed system combined with a cooler to improve the positioning accuracy of the machine tool. In this study, the supply oil temperature in the structural cooling channels was found to significantly affect the position accuracy of the moving table and moving carrier. If the supply oil temperature in the cooling channels is consistent with the operational ambient temperature, the position accuracy of the moving table in the Y direction and the moving carrier in the X and Z directions has the best performance under different feed rates. From the thermal suppression experiments of the embedded cooling channels, the positioning accuracy of the feed system can be improved by approximately 25.5 % during the dynamic feeding process. Furthermore, when the hydrostatic guideway is cooled and dynamic feeding is conducted, positioning accuracy can be improved by up to 47.8 %. The machining accuracy can be improved by approximately 60 % on average by using the embedded cooling channels in this study. Therefore, thermal suppression by the cooling channels in this study can not only effectively improve the positioning accuracy but also enhance machining accuracy, proving that the method is effective for enhancing machine tool accuracy.

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Analysis on Effect of Cooling Oil Temperature on Cutting Stability of Gear Shaping Machine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.651-653.647 ◽

2014 ◽

Vol 651-653 ◽

pp. 647-650

Author(s):

Hai Tao Yu ◽

Lie Chen ◽

Chang Bing Zhou ◽

Rui Wen Guo

Keyword(s):

Machine Tool ◽

Processing System ◽

Cutting Stability ◽

Capability Index ◽

Cutting Test ◽

Machine Tool Accuracy ◽

The Stability ◽

Gear Shaping ◽

Accuracy And Stability

With the demands of machine tool accuracy and stability for manufacturing are getting higher and higher, the effect of cooling oil is increasingly evident. And it is proved that cooling oil temperature is an important factor for machine cutting precision and stability. Continuous cutting test was carried on and values of over pin dial (M) were measured. The results show that it has large effect of cooling oil temperature on the stability of M-value. Subsequently, test of machine capability index (CMK) was carried on. And it was verified that the CMK of gear shaping machine is larger than 1.67. And the results show that the fluctuation of M values is the smallest when cooling oil temperature is 33°C. Lowest time costing for adjusting the processing system, highest cutting accuracy, and smallest value of stable amplitude for Gear Shaping Machine could be obtained at this condition.

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Machine Tool Accuracy and Metrology

Analysis of Machining and Machine Tools ◽

10.1007/978-1-4899-7645-1_6 ◽

2015 ◽

pp. 95-111

Author(s):

Steven Y. Liang ◽

Albert J. Shih

Keyword(s):

Machine Tool ◽

Machine Tool Accuracy

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Study on the Stability of High-Speed Milling of Thin-Walled Workpiece

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.1849 ◽

2010 ◽

Vol 97-101 ◽

pp. 1849-1852

Author(s):

Tong Yue Wang ◽

Ning He ◽

Liang Li

Keyword(s):

Aluminum Alloy ◽

Machine Tool ◽

High Speed ◽

Modal Parameters ◽

Inertia Effect ◽

Cutting Force Coefficients ◽

High Speed Milling ◽

Machining System ◽

Thin Walled ◽

The Stability

Thin-walled structure is easy to vibrate in machining. The dynamic milling model of thin-walled workpiece is analyzed based on the analysis of degrees in two perpendicular directions of machine tool-workpiece system. In high speed milling of 2A12 aluminum alloy, the compensation method based on the modification of inertia effect is proposed and accurate cutting force coefficients are obtained. The machining system is divided into “spindle-cutter” and “workpiece-fixture” two sub-systems and the modal parameters of two sub-systems are acquired via modal analysis experiments. Finally, the stability lobes for high speed milling of 2A12 thin-walled workpiece are obtained by the use of these parameters. The results are verified against cutting tests.

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Development of smart machining system for optimizing feedrates to minimize machining time

Journal of Computational Design and Engineering ◽

10.1016/j.jcde.2017.12.004 ◽

2017 ◽

Vol 5 (3) ◽

pp. 299-304 ◽

Cited By ~ 7

Author(s):

Hong-seok Park ◽

Bowen Qi ◽

Duck-Viet Dang ◽

Dae Yu Park

Keyword(s):

Cutting Force ◽

Machining Process ◽

Cnc Machine ◽

Machining Time ◽

Virtual Machining ◽

Milling Operations ◽

Nc Program ◽

Machining System ◽

Optimal Feed ◽

Smart Machining

Abstract Feedrate optimization is an important aspect of getting shorter machining time and increase the potential of efficient machining. This paper presents an autonomous machining system and optimization strategies to predict and improve the performance of milling operations. The machining process was simulated and analyzed in virtual machining framework to extract cutter-workpiece engagement conditions. Cutting force along the cutting segmentation is evaluated based on the laws of mechanics of milling. In simulation, constraint-based optimization scheme was used to maximize the cutting force by calculating acceptable feedrate levels as the optimizing strategy. The intelligent algorithm was integrated into autonomous machining system to modify NC program to accommodate these new feedrates values. The experiment using optimized NC file which generates by our smart machining system were conducted. The result showed autonomous machining system, was effectively reduced 26%. Highlights The smart machining system was implemented in the CNC machine. Optimal feed rates enhance machine tool efficiency. The smart machining system is reliable to reduce machine time.

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VIRTUAL MACHINING SYSTEM ENGINE FOR SIMULATION OF THE PROCESS MACHINE INTERACTION

MM Science Journal ◽

10.17973/mmsj.2012_03_201204 ◽

2012 ◽

Vol 2012 (01) ◽

pp. 310-314

Author(s):

Andreas Archenti ◽

Mihai Nicolescu ◽

Thomas Lundholm

Keyword(s):

Virtual Machining ◽

Machining System ◽

Machine Interaction ◽

Process Machine Interaction

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An Accuracy-Prediction Model Taking Tool Deformation and Geometric Machine-Tool Error into Consideration

International Journal of Automation Technology ◽

10.20965/ijat.2010.p0235 ◽

2010 ◽

Vol 4 (3) ◽

pp. 235-242 ◽

Cited By ~ 3

Author(s):

Hirohisa Narita ◽

◽

Keiichi Shirase ◽

Eiji Arai ◽

Hideo Fujimoto ◽

...

Keyword(s):

Prediction Model ◽

Machine Tool ◽

End Milling ◽

Geometric Error ◽

Cutting Conditions ◽

Error Prediction ◽

Machining Accuracy ◽

Trial And Error ◽

Virtual Machining ◽

Nc Program

Test cutting used to verify cutting conditions and machining accuracy after a numeric control (NC) program is written for end milling the mold and die indispensable to manufacturing is generally effective, because it is based on trial and error. The virtual machining simulator we designed to verify machining accuracy uses an accuracy-prediction model and an error prediction expression for workpieces, integrating machine-tool deformation and geometric error models. We also propose calculation for copying errors to a workpiece.

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A unified manufacturing resource model for representation of computerized numerically controlled machine tools

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

10.1243/09544054jem1363 ◽

2009 ◽

Vol 223 (5) ◽

pp. 463-483 ◽

Cited By ~ 20

Author(s):

P Vichare ◽

A Nassehi ◽

S Newman

Keyword(s):

Machine Tool ◽

Machine Tools ◽

Manufacturing System ◽

Cutting Tools ◽

Cnc Machining ◽

Cnc Machine Tools ◽

Cnc Machine ◽

Resource Model ◽

Machining System ◽

Manufacturing Resource

The capability of any manufacturing system primarily depends on its available machine tools. Thus machine tool representation is a vital part of modelling any manufacturing system. With the rapid advances in computerized numerically controlled (CNC) machines, machine tool representation has become a more challenging task than ever before. Today's CNC machine tools are more than just automated manufacturing machines, as they can be considered multi-purpose, multi-tasking, and hybrid machining centres. This paper presents a versatile methodology for representing such state-of-the-art CNC machining system resources. A machine tool model is a conceptual representation of the real machine tool and provides a logical framework for representing its functionality in the manufacturing system. There are several commercial modelling tools available in the market for modelling machine tools. However, there is no common methodology among them to represent the wide diversity of machine tool configurations. These modelling tools are either machine vendor specific or limited in their scope to represent machine tool capability. In addition, the current information models of STEP-NC, namely ISO 14649, can only describe machining operations, technologies, cutting tools, and product geometries. However, they do not support the representation of machine tools. The proposed unified manufacturing resource model (UMRM) has a data model which can fill this gap by providing machine specific data in the form of an EXPRESS schema and act as a complementary part to the STEP-NC standard to represent various machine tools in a standardized form. UMRM is flexible enough to represent any type of CNC machining centre. This machine tool representation can be utilized to represent machine tool functionality and consequential process capabilities for allocating resources for process planning and machining.

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