High-speed Machining Center Research Articles

A step towards the holistic modelling of the HSC machining centre and the efficient compensation of its errors

This article deals with the integrated holistic modelling of 5-axis high-speed machining centres and the main error sources located in the rotating control axes. A strategy for reducing and effectively compensating thermal errors is presented. The strategy includes steps of error recognition based on knowledge, modelling, numerical simulation analysis and mutual interactions. A holistic hybrid model of spindle axial displacements caused by high spindle rotational speeds is described. Attention is given to the modelling of displacements arising in the spindle assembly (due to centrifugal forces) and in the tilting table with direct drives in axes A and C. The conditions that the prognostic modelling of thermal errors must satisfy to ensure the effective compensation of the latter are discussed and error identification methods are presented.

Finite Element Analysis of Static and Dynamic Characteristics of High-Speed Horizontal Machining Center Bed

Based on the theory of finite element and modal analysis theory, analysis of static and dynamic characteristics of the lathe bed has been done. The static displacement contours and mode natural frequency and displacement contours have been given to realize the structure optimization of lathe bed of high-speed horizontal machining center. It is shown that the bed has good static stiffness and natural frequency and the deformation of lathe bed mainly occurred in the tray conversion mechanism and the cutter location. The deformation of processing work area is small and has certain light weight space, which lay the foundation for the lightweight design of the bed.

An experimental investigation of spindle rotary error on high-speed machining center

A method is described in this paper for measuring the spindle rotation error and a technique for separating the eccentric error caused by setup error of the master cylinder. The system consists of two non-contact capacitance sensors used to measure the radial displacement of the rotating master cylinder and an LMS Test.Lab used to collect the measurement data. LMS Test.Lab offers a complete engineering solution for rotating machinery. Based on our experimental research, it indicates that this system can be used to measuring the spindle rotary error at different speeds. It is also verified the feasibility of the error separation methods developed in this paper.

RETRACTED: Structure Optimization of High-Speed Machining Center Workbench Based on Bionic Design and Hierarchical Optimization Techniques

Retracted article: We aimed at high speed machining center high machining accuracy and lightweight design requirements ,Then design the two different stiffened plate structure workbench, The one use traditional design method, the other use bionic design method; Optimize the dimensions of bionic stiffened plate design based on CAD/CAE system integration and hierarchical optimization techniques, got the optimal size; through the static analysis and modal analysis verify the superiority of the optimization schemes.

Effect of trajectory-controlled algorithm on the mechatronical performance of high-speed machining

For high-speed machining, the position commands from the trajectory-controlled algorithm should be as smooth as possible since even a small discontinuity in position command may lead to vibrations of the mechanical structure and the servo system. A simplified mechatronic model was proposed to analyze the impact of the trajectory-controlled algorithm on the performance of high-speed machining. The effects of the control loop parameters and natural frequency of mechanical structure on the vibration were also studied. Experimental tests on the vertical z-axis of a high-speed machining center indicate that the presented methodology is able to evaluate the evolution of the vibration due to the trajectory-controlled algorithm, and it is also helpful to choose the suitable controlled parameters for improving the mechatronic performance of high-speed machining.

The Topological Optimization of High-Speed Vertical Machining Center Worktable

In this paper, high-speed vertical machining center of the four schemes(namely general reinforcement worktable, strength general reinforcement worktable, diagonal reinforcement worktable and strength diagonal reinforcement worktable) has been entity modeling in Soldworks. After modeling, do finite element analysis and stiffness analysis to four schemes, the conclusion shows strength reinforcement worktable is the best plan. Then, do modal analysis in order to improve the inherent frequency, get the modal of the system frequency and vibration mode. Finally, according to the results of analysis of static dynamics, in order to improve the natural frequencies of strength general reinforcement system, the worktable has been topological optimization. Because of the result of the topological optimization is not obvious, so choose workbench is verified by reasonable structure.

Optimization of DVG850 Dual-Screw Worktable System Based on ANSYS Workbench

In traditional single-screw worktable system, the system is always subjected with torque because the driving force and force-bearing point of the workpiece always change with the processing path, so its performance may be affected. Therefore, the scheme of dual-screw worktable system is put forward and modal analysis with ANSYS Workbench is made by taking DVG850 high-speed vertical machining center worktable system for example. Then four alternatives of the machine are proposed based on the position of screw and guide.Through modal analysis of different parameters of the system, we ultimately select the dual-screw worktable system with highest performance (Screws place inside of the guide and horizontal distance of the two screws is 310mm.) as the optimalizing plan. This provides a reliable reference for further study on dynamic analysis of worktable system.

Modeling of tool wear for ball end milling cutter based on shape mapping

Tool wear is thus of great importance to understand and quantitatively predict tool life. In this paper, a tool wear model for ball end milling cutter is established with considering the joint effect of machining conditions for predicting tool wear. The modelling process of tool wear is given and discussed according to the specific conditions. In order to determine coefficients of the established tool wear model a new tool wear estimation method based on shape mapping is used to measure tool wear which is suitable to prepare tool wear data for the established model. So tool wear for each experiment can be obtained from the tool wear estimation method and be used to fit the proposed tool wear model by using multiple linear regression method. Experimental work and validation are performed on five-axis high speed machining centre for cemented carbide cutting tool milling stainless steel. Experimental results indicate that tool wear can be predicted within 10 % on an average using the established tool wear model and the established tool wear model is suitable to predict tool wear at certain range of cutting conditions for milling operation.

Static and Dynamic Performance of High-Speed Vertical Machining Center Spindle Box

In order to improve the static performance of high speed machining center spindle box, using ANSYS software static performance analysis, static analysis of finite element method to the complex structure of the spindle box, draw a box structure under the force load and temperature load stiffness theoretical values, emphasizing the factors affecting temperature deformation, provides a basis to improve and control the strength and stiffness of the spindle box, as well as box optimization design of the design constraints.

Optimization Design of DVG850 Worktable System Based on ANSYS Workbench

The finite element model of worktable system is created and modal analysis is made with ANSYS Workbench by taking DVG850 high-speed vertical machining center worktable system for example. We make modal analysis of single-screw strength general reinforcement worktable system and get the natural frequency and the vibration mode.Then in order to improve the system's natural frequency, the scheme of dual-screw worktable system is put forward. Also natural frequency and vibration mode is got. Finally, it is proved that the performance of dual-screw worktable system is significantly better than the single-screw one. This provides a reliable reference for further study on dynamic analysis of worktable system.

Dynamic Analysis of DVG 850 High-Speed Machining Center

Purpose, with the application of workbench finite element analysis software, get the analysis results of DVG 850 high-speed vertical machining center via the modal analysis and harmonic response analysis. Use the calculation results for reference, put forward the improved method, and prove the credibility of the simulation analysis by testing DVG 850 prototype.

Mechanical properties and cutting performance of Cr–Al–N hybrid coated micro-tool for micro high-speed machining of flexible fine die

In this paper, comparative studies on mechanical properties and cutting performance between CrN and Cr–Al–N coatings for high-speed machining of flexible fine die (FFD) were conducted. Ternary Cr–Al–N coatings, in which Al was incorporated into CrN, were synthesized onto WC–Co substrates using a hybrid coating system of arc ion plating and sputtering techniques. From XRD analysis the nanocomposite Cr–Al–N coatings were related to the composite microstructure consisting of the fine CrN crystallites and amorphous Si3N4. The average friction coefficient of Cr–Al–N coatings gradually decreased with Al content in CrN coatings. The values of tool wear for uncoated, CrN and Cr–Al–N coated tools were evaluated under a high-speed cutting condition using a vertical high-speed machining center. Consequently, the ternary Cr–Al–N coated micro-tool showed good cutting performance under micro high-speed machining of AISI W1-8 steel of hardness 52 HRC for flexible fine die.

Vibration Characteristics Analysis of a High-Speed Horizontal Machining Center

By the experimental modal testing to the main structure of the high-speed horizontal machining center，the modal parameters such as the natural frequency, damping ratio, stiffness and mode shapes are obtained. By analyzing the vibration characteristics, the critical components of the machining center is at the spindle front bearing part and the vertical column on which the screw driving spindle box to move in vertical direction is mounted are determined, and provide an important basis of optimizing the structure for the machining center. And the amplitude-frequency characteristic curves of the critical components evaluate the dynamic stiffness as the key indicators to provide reliable data for improving processing accuracy and cutting ability of machining center.

Thermal Analysis and Experimental Study on the Spindle of the High-Speed Machining Center

By taking the spindle system of high speed and high precision machining center as the research object, the finite element method is used to make the thermal analysis and the thermal-structure coupling analysis. In this paper, the heat dissipating capability of cooling system of spindle system is simulated and the thermal deformation is predicted. The result of simulation can provide reference for the solid design of spindle system.

Structure Topology Optimization of the Spindle Box of a Machining Center

To meet the need of high precision and speed, the movable parts of a high speed machining center should be as light as possible with high stiffness, which can be realized effectively via structure topology optimization. In this paper, structure topology optimization of the spindle box of a type of machining center was carried out based on the software of OptiStruct of HyperWorks. In the course of design, a stiffness criterion was put forward to deal with the uncertainty of cutting load on a machining center. And based on the criterion, the load boundary condition of the spindle box model was defined. And a clear structure was finaly obtained in the postprocessor of OptiStruct.

Fuzzy Finite Element Optimization of High-Speed Vertical Machining Center Spindle Box

The key component of the spindle box for using the fuzzy optimization method for high-speed vertical machining center was optimized. Through the analysis of the fuzzy information of the components, the membership functions of the constraint were determined, and the satisfactory results were obtained according to the characteristics of the actual problems or decision-makers intention. Through fuzzy finite element method, the optimal solution in the space was adjusted, the design of multiple choices was provided for designers, and the favorable conditions for other design of parts were created.

Optimization Design on Headstock of Shape High-Speed Vertical Machining Center

Optimization design was a technology that searched and determined the optimal design. Parametric model of headstock was established in Pro/E, and the parametric model was imported into the ANSYS Workbench. Then multi-objective optimization design was carried out in DesignXplorer module based on test technology, response surface that the combinations of design variables aimed at the objective function was obtained, the situation which design variables changes impacted on performance parameters from the response surface was viewed, a relatively ideal optimal design result was chosen. The mass of improved headstock was reduced, under the condition that performance in all aspects was not diminished.

Structure Analysis and Optimization for High-Speed Vertical Machining Tool Table

In order to meet high-speed machining center’s overall performance requirements, there are four different worktable structures established in SolidWorks, and they are carried out static analysis in ANSYS Workbench to calculate their static stiffness, so that find out the best structure. In meeting the worktable stiffness, the best structure is optimized in ANSYS Workbench, then the worktable’s quality reduces 8.43% in the original foundation and the cost also decreases, which is a basis for worktable’s dynamic performance analysis.

Development of a feed rate adaption control system for high-speed rough and finish end-milling of hardened EN24 steel

High-speed machining centers are used for end-milling operations of a variety of parts, dies, and molds needed in power and transport industries. Different approaches are used for rough and finish end-milling, since desired productivity and quality are important in the respective cases. In the present work, a feed rate adaption control system is proposed by integrating different requirements of high-speed end-milling. Hardened EN 24 steel which is being widely used in the production of dies, molds, and other parts is taken as a candidate work material for implementation of the proposed control system. Based on extensive experimentation, investigations have been carried out on high-speed rough and finish end-milling operations, and the details are reported by the authors (Saikumar and Shunmugam, Int J Adv Manuf Technol, under review). In this paper, relevant response surface and artificial neural network models have been used, and suitable reference parameters are obtained for the proposed control system. In the case of rough end-milling, material removal volume is taken as the objective, and the reference values for cutting force and cutting time are used. Only a reference cutting force is used for finish end-milling in which surface roughness is considered as the objective. Implementation details of the proposed PC-based control system are presented. The results obtained for a newly devised H–A–S–H test (short run) along with those for long-run tests are presented and discussed.

Static & Dynamic Analysis and Optimization of DVG850 High-Speed Vertical Processing Center

The main structure of DVG850 high-speed vertical machining center is instructed in the paper, the solid 3D model of the machine is established by SolidWorks, and then improted into ANSYS Workbench to do static and dynamic analysis. Firstly, the static analysis of high-speed vertical machining center is studied to get the deformation figures. From the analysis of the deformation figures, we can find the locations of weak static stiffness. Next, the modal analysis is studied and the order of natural frequencies we need are obtained. Through the analysis of the vibration modes of this machine tools, its relative weaker parts are pointed. Finally, The structure of the machine tools is improved according to the analysis results. The static and dynamic characteristics of the improved structure are apparently better than that of the original design. It makes a base for optimized design and remanufacturing. .