Milling Machining Center Research Articles

Geometrical feature analysis of Co-Cr-Mo single tracks after selective laser melting processing

Purpose – Therefore, the purpose of this study is to understand the relationships between the processing parameters and the geometric form of the produced single tracks, in order to control dimensional quality in future experimentations. The quality of the deposited single track and layer is of prime importance in the selective laser melting (SLM) process, as it affects the product quality in terms of dimensional precision and product performance. Design/methodology/approach – In this paper, a vertical milling machining center equipped with an Ytterbium-fiber laser was used in the SLM experimentation to form single cobalt-chromium-molybdenum (CoCrMo) tracks. The different geometric features and the influence of the scanning parameters on these morphologic characteristics were studied statistically by means of ANOVA. Findings – Evidently, track height (h1) inaccuracy reduced in layer thicknesses between 100 and 200 μm. The re-melt depth (h2) was determined by the energy parameters, with laser power of 325-350 W and scanning speed (SS) of 66.6-83.3 mm/s being the most favorable parameters to obtain the required anchoring. Moreover, a contact angle of 117° was proposed as optimal, as it permitted an adequate overlapping region and a full densification, and, finally, an SS of 50 mm/s and a layer thickness of 250 were suggested for its development. Originality/value – The comprehension of the phenomena inherent to the process is related to the single track geometrical characteristics, which allow the definition of an optimal value for each factor for a further proposal of processing conditions that can finally derive a higher precision, wetting, density and mechanical properties.

Design Method of B-Axis Components of Water Chamber Head Turning and Milling Machining Center

Aiming at the demands of nuclear water chamber head’s multi-inclined holes and ramps in boring and milling, based on design requirements of special turning and milling machining center, B-axis structural design is put forward, research on deformation characteristics of ram components under different swing angle, propose the control methods of deformation and errors. Adopt modeling method of equal mass, construction of deformation and displacement analysis model of B-axis components, explore formation reason of maximum gap between components’ joint surface, form optimization design scheme of rotation structure of B-axis components. Trial-produce prototype of B-axis components, make experiment of trial cut water chamber head in turning and milling machining center, utilize test results of part's machining quality, verify unloading effects and machining accuracy of design scheme of B-axis components has been verified.

Static and Dynamic Characteristics Analysis of HTM125 Milling Complex Machining Center Column

The column of heavy double turret five-axis horizontal milling complex machining center is taken as the object of study. Solidworks is used to establish three-dimensional model of milling machining center column, the established modal is be imported into ANSYS Workbench for static and dynamic characteristics analysis. First, by comparing the column deformation, the stress and strain under no-load and load conditions, which is concluded that column design is too conservative and be optimized. Secondly, the modal analysis was carried out on the column, which provides a theoretical basis for the optimization of the column by getting the first six natural frequencies and mode shapes of cloud.

Based on Concept of Generalized Instantaneous Space of Dynamic Performance Analysis

TX1600 boring and milling machining center milling part was studied. The Three-dimensional solid model was established based on Solidworks. Simultaneously, modal analysis was carried out by ANSYS Workbench software, the first six natural frequencies and corresponding modes were acquired. Based on the modal analysis, the harmonic response analysis of milling part was conducted,and the response curves of the three main motion orientation were obtained respectively, the vibration performance of milling part under forces was further explored,and the finite element model was validated. The feasibility of the model to simplify the program was verified by modal and harmonic response analysis. The study provides a good basis in terms of selecting a specific material. The structures and material are optimized. Ultimately, a lot of energy is saved.

Research on Deflection Analysis and Compensation Method of Ram of Boring and Milling Machining Center

In this paper, the ram of boring and milling machining center is taken as the research object. A new method that hydraulic pull rods compensation is proposed to solve the problem of deformation compensation of long stroke ram of boring and milling machining center. Firstly, the method of finite element analysis is used to get the laws of ram deformation and the relationship curve between the ram deformation and the stroke of ram. Secondly, the preliminary calculation value of pull rods compensation force is derived based on the theoretical analysis of material mechanics. The relationship curve between compensation force and the stroke of ram is obtained by finite element analysis and polynomial least squares method. Finally, the analyzed results are as follows: the laws of ram deformation distribution is accurately predicted by the used method, the deflection error of the ram is well controlled,and the machining precision is significantly improved.

The Origin Alignment Method of Box Parts Based on Boring and Milling Machining Center

Based on complex body parts structure, the characteristics of batch processing and high accuracy requirement, in order to improve the efficiency of its alignment, put forward about the case accessories are the method of study the origin. During the study, in order to type boring and milling machining center for processing platform, build online detecting system for the body parts. By mathematical modeling and knowledge of analytic geometry, the rotary table any position of body parts in machining center is to find the origin, and determine the size of the work-piece origin of coordinates and the deflection angle. Checked by practice, this method is suitable for composite boring and milling machining center mass production of body parts in work, improve the efficiency of the box body parts processing precision and alignment.

Design of the B-Axis of the Water Chamber Special Turn-Milling Center

As the key part of nuclear pressure vessels, the water chamber head has the features of large size, complex shape and difficult processability. The processes of conventional machining method are too decentralized, the cumulative error is large, and the processing cycle is long. In order to meet the efficiency and high-precision machining requirements of the nuclear power water chamber head, a design scheme of special turn-milling machining center and B-axis components is proposed. The part characteristics and machining difficulties of the water chamber head are analyzed in the paper. The machining areas and processes are subdivided, the numerical control technological process is presented. In order to complete the finish machining of the water chamber's inner and outer surfaces and its inclined holes and sloping faces, the movable gantry milling machining center with pendulant ram is designed. According to the head processing requirements, three design schemes of B-axis components assembly, single row cylindrical roller bearing type, double row tapered roller bearing type and the central axis unloading type, are proposed. Through the theory analysis and statics and modal comparative analysis, the central axis unloading type is adopted as the optimal proposal in B-axis component design. Simulation and experimental results show that the turn-milling machining center based on the unloading B-axis assembly can satisfy the precision requirement of the water chamber head.

Turning-Milling Machining Center Headstock Assembly Design

analyze the headstock structure and milling machining center, build a new assembly file; Will, in turn, components used in the assembly file is inserted into the assembly file. Using UG to complete the assembly process of virtual assembly, generate the explosion view.

Thermal Error Compensation on Boring & Milling Machining Center Feed System Based on PMAC

Aiming to deal with thermal error of NC machine tool which can cause reduce of machining accuracy, this paper uses an external error compensation which interacts with NC controllers and PMAC multi-axis and then revises the tool path by adding the error tested in real-time by PMAC card. The processing accuracy is improved eventually. This method can compensate machine geometric errors and thermal errors in real-time. Comparing with other methods of error preventing, this method is more effective and affordable.

The Flexible Control System Development of the Sawing and Milling Machining Center for PVC Door and Window Profile

In the paper, with the secondary development of FANUC-0MD system, the flexible control system which meets the requirements of the sawing and milling machining center for PVC door and window profile is realized. Based on researching the structure, the function, the process of the technologies and the control requirements of the machining center, the CNC system has implemented, including the machine tool origin and work piece coordinate origin establishment and auxiliary control system M code development. In this flexible control system, through studying the geometric character, the technical character and the mutual relation between them, various windows shape on the structure and the machining figuration is possessed of. We gain the feature subclasses aggregate of the machining technology of windows shape. Consequently, CAM system is achieved.

Turning-Milling Machining Center of Each Axis Movement Principle and the Headstock Structure Analysis

Turning milling machining center are analyzed the structure and working principle of headstock of numerical control machine tool headstock consists of motor, drive system and components of the head of a bed, is mainly used to achieve the main movement of the machine tool. Spindle structure adopts precision double row cylindrical roller bearing and two-way thrust angular contact ball bearing group and type. The machine is the best combination of lathe and milling machine. Configuration French NUM1060 system, realize five axis control, a loading card can complete a variety of difficult machining of complex.

Turning-Milling Machining Center Spindle Box of 3D Design

car milling machining center spindle box is mainly composed of the spindle and the spindle on the relevant parts, enclosure, encoder related parts and some standard parts. Using UG unique components modeling based on feature function, using the stretching, rotating, reinforcement, lofting and scanning, array characteristics and drilling easy design components of the three-dimensional entity, and in the process, modifying the shape and size, complete the optimization design.

A Novel Local Time-Frequency Domain Feature Extraction Method for Tool Condition Monitoring Using S-Transform and Genetic Algorithm

This paper investigates an online effective method for tool condition monitoring. Acoustic emission signal of a system which is acquired by a sensor mounted to the spindle of the milling machining center is used as the fault indicator because it is easily to be installed, inexpensive and practical for use in industrial environment. Time-frequency analysis is selected for signal processing step based on its ability to reveal time and frequency variant characteristics of faulty signal. S-transform is used as a powerful time-frequency method for this purpose. Because of the high dimension of the time-frequency results, it is desirable to use a local region of interest in time-frequency domain instead of using the entire information, for fast and accurate monitoring and detection when any abnormal/fault operating condition might occur. Such a strategy also helps to reduce the computation cost which is necessary for online applications and improves the interpretation resolution for law quality signals. An optimization method based on genetic algorithm is used for finding the most discriminative local area as the region of interest in time-frequency domain. For feature generation step, a correlation coefficient between each signal and the healthy signal is assigned to the signal using a 2-D correlation analysis. Curve fitting approach is then used to determine a function to approximate the fault value based on the correlation coefficients. Experimental results based on a milling machine under different operating conditions show that this method has a high accuracy for fault detection. It is also concluded that the accuracy of the local feature extraction is higher than the conventional ways.

Process Route Optimization for Machining Center NC Milling Manufacturing

There are some characteristics about CNC milling machining centers, such as the procedures are concentrated, the procedure steps are complex, the machining cost is expensive and so on. A mathematical model was established to optimize the process route for machining center NC milling manufacturing. It wants to make the time of machining a single part is shorter or the cost of machining a single part is lower. A using example was given.

Turning and Milling Machining Center Spindle Box of Three Dimensional Design

the car milling machining center spindle box mainly by the spindle and the spindle on relevant parts, body, encoder related parts and some standard composition, the application of UG unique based on characteristics of the parts and components modeling function, the use of tensile, rotating, tendons, lofting and scanning, array characteristics and drilling easily design components of the three-dimensional entity.

Design of an Automatic Tool Changer System for Milling Machining Centers

In the field of manufacturing processes it is observed that the trend is to produce more and more fast, efficiently parts with high complexity, which involves using a high number of tools in the machining process. One of the main solutions for high speed and efficient manufacturing is based on the full automation of the entire manufacturing process. The automatic changing of the tools involved in the manufacturing process is carried out by the automatic tool changing mechanism, thus the auxiliary non-productive time consumed with the tool change is highly minimized. In this paper we present a novel automatic tool changer which is both simple and compact, and any milling machining center provided with chain or disc tool magazine can be equipped with. Also by adopting the use of this tool changing mechanism other subassemblies of the tool changing system, such as the tool transfer mechanism and the waiting position, are substituted by this changing mechanism. The auxiliary movements needed to bring the tool from the magazine into the waiting position are overlapped with the machining time, so that the total time for exchanging the tool in the spindle with the tool from the magazine is minimized.

Static Stiffness Analysis and Modal Analysis of Horizontal Milling & Turning Machining Center

In order to in-depth study the weak part of the turning operation of the turning and milling machining centers during the work process, the three-dimensional structure model is established, and the static stiffness analysis and modal analysis are carried out. The deformation of each main part is grasped, which can determine the main deformation component. All above will provide the theoretical basis for future improvement of the machining centers.

ASSURANCE OF THE QUALITY OF PROCESSING OF COMPLEX CONTOURED PARTS ON MACHINES WITH VARIABLE ELEMENTS

The article highlights the problems arising during processing of parts with a complex contoured profile. There are considered all the stages of formation of the geometrical image of the machine with variable elements. The authors formed a complex of 3D-geometric models of Finc Tech SMV-450-H3 milling machining center, which allows to quickly edit the components without changing the overall structure of the model.

Double-Spindle Symmetrical Machining to Improve Machining Efficiency

In order to improve the machining efficiency of the duralumin turbine rotor of maglev molecular pump, this paper proposes a new double-spindle horizontal milling machining center structure. Through a brief introduction to other types of machine tools, describes the characteristics of this new machine tool and symmetrical machining implementation. This paper proposes a new double-spindle horizontal milling machining centers so that the machining efficiency of duralumin turbine rotors is improve 100% more than that of the traditional machine tool in theory. Moreover, its machining accuracy get relative improve as the decrease of the dividing accumulative error. At the same time, the cost of workpiece is reduced greatly.

BUEVA: a bi-directional ultrasonic elliptical vibration actuator for micromachining

This paper presents a novel actuator design for vibration-induced micromachining. The bi-directional ultra- sonic elliptical vibration actuator (BUEVA) possesses a combination of features that renders it suitable for the machining a wide range of materials over a variety of cutting parameters. The cutting motion is an elliptical tool motion that resembles "spoon feeding". This cutting action is in contrast to in-plane, horizontal motion utilized by most existing setups. The motion is arrived at through a combination of motions along the tool's axial and transverse directions and by vibrating out of phase and is generated by two stacked ceramic multilayer actuator ring piezo elements. Another distinguishing feature of BUEVA is the use of piezo stacks which ensure high blocking force compared to low force of piezo benders as used in many existing actuators. Furthermore, the amplitude and frequency of vibration of the tool are controlled on-line in order to vary the cutting depth and cutting speed according to the desired cutting parameters. This is a desirable characteristic which allows one to "dial-in" a desirable cutting speed for different workpiece materials. Another attractive BUEVA feature is that the design is very compact and can fit easily into the working space of most milling machining centers without the need for custom motion setups. An off the shelf TiALN- coated carbide turning tool is utilized as the cutting tool. Furthermore, refined versions of previously reported models by other workers in the micromachining field have been developed. Experimental force and surface roughness measurements are compared versus these ideal calculations from the improved models. Compared with these reference models, our refined calculations show improvements in describing chip geometry based on corrected tool motion and which, consequently, resulted in improved estimates of both surface roughness and cutting forces. Verification cutting tests in two different materials (Al2024 and Plexiglas) show good surface integrity and dimensional definition with roughness measurements in reasonable correlation to the refined model calculations.