Design of a five-axis ultra-precision micro-milling machine—UltraMill. Part 1: Holistic design approach, design considerations and specifications

High-accuracy three-dimensional miniature components and microstructures are increasingly in demand in the sector of electro-optics, automotive, biotechnology, aerospace and information-technology industries. A rational approach to mechanical micro machining is to develop ultra-precision machines with small footprints. In part 1 of this two-part paper, the-state-of-the-art of ultra-precision machines with micro-machining capability is critically reviewed. The design considerations and specifications of a five-axis ultra-precision micro-milling machine—UltraMill—are discussed. Three prioritised design issues: motion accuracy, dynamic stiffness and thermal stability, formulate the holistic design approach for UltraMill. This approach has been applied to the development of key machine components and their integration so as to achieve high accuracy and nanometer surface finish

Super Abrasive Machining of Integral Rotary Components Using Grinding Flank Tools

Manufacturing techniques that are applied to turbomachinery components represent a challenge in the aeronautic sector. These components require high resistant super-alloys in order to satisfy the extreme working conditions they have to support during their useful life. Besides, in the particular case of Integrally Bladed Rotors (IBR), usually present complex geometries that need to be roughed and finished by milling and grinding processes, respectively. In order to improve their manufacturing processes, Super Abrasive Machining (SAM) is presented as a solution because it combines the advantages of the use of grinding tools with milling feed rates. However, this innovative technique usually needed high tool rotary speed and pure cutting oils cooling. These issues implied that SAM technique was not feasible in conventional machining centers. In this work, these matters were tackled and the possibility of using SAM in these five-axis centers with emulsion coolants was achieved. To verify this approach, Inconel 718 single blades with non-ruled surfaces were manufactured with Flank-SAM technique and conventional milling process, analyzing cutting forces, surface roughness, and dimension accuracy in both cases. The results show that SAM implies a suitable, controllable, and predictable process to improve the manufacture of aeronautical critical components, such as IBR.This work is based on TURBO project (DPI2013-46164-C2-1-R) of the Spanish Ministry of Economy and Competitiveness. Also, the authors wish to acknowledge the financial support received from HAZITEK program, from the Department of Economic Development and Infrastructures of the Basque Government and from FEDER founds, related to the project with acronym HEMATEX. Besides, the authors would like to thanks as well to BCAM for its collaboration. Finally, thanks are also addressed to Spanish Project MINECO DPI2016-74845-R and RTC-2014-1861-4

Computer numerical controlled (CNC) machining of screws and dies for plasticating extruders : determination of the criteria for implementing CNC machining

The work of this thesis is dedicated to the manufacturing industry making production equipment to manufacture plastic products. The main theme of the thesis is to determine the criteria for implementing Computer Numerical Control machining to make parts with complex geometries for production equipment. A small manufacturing company with job shop type of production was chosen as the subject and study of extruder manufacturing process was performed. The various available alternatives of CNC manufacturing units available in the market were chosen and their feasibility examined. At present a large variety of CNC machine tools are available in the market, offered by manufacturers following different standards. This thesis is organized with the purpose of comparing various technical and economical considerations for CNC machine tool purchase and its application

Motion error and accuracy evaluation method for CNC vertical milling machine

This report represents a method that uses the double ball bar to inspect motion errors of the rotary axes of three axis CNC milling machine tools. This method uses a particular circular test path that only causes the two rotary axes to move simultaneously and keeps the other linear axes stationary. Therefore, only motion errors of the two rotary axes will be measured during the double ball bar test. Minimum circular radius that can be inspecting with standard double ball bar circular interpolation test kit is l 50mm. Therefore, machine with less than 150mm circular radius need to use measuring magnification in order to enable the circular interpolation test by double ball bar method. The characteristic of measuring magnification for machine with circular radius less than 150mm is proposed. The theoretical trace pattern of error origins which is squareness error is established. Consequently, the error origins in the rotary block can be diagnosed by examining whether similar patterns appear in the motion error trace. Testing procedure performed by means of detecting the motion errors characteristic. Then based from this trace pattern, the current state of the machines can be known and this information is beneficial for the user to take necessary actions

Super Abrasive Machining of Integral Rotary Components Using Grinding Flank Tools

Manufacturing techniques that are applied to turbomachinery components represent a challenge in the aeronautic sector. These components require high resistant super-alloys in order to satisfy the extreme working conditions they have to support during their useful life. Besides, in the particular case of Integrally Bladed Rotors (IBR), usually present complex geometries that need to be roughed and finished by milling and grinding processes, respectively. In order to improve their manufacturing processes, Super Abrasive Machining (SAM) is presented as a solution because it combines the advantages of the use of grinding tools with milling feed rates. However, this innovative technique usually needed high tool rotary speed and pure cutting oils cooling. These issues implied that SAM technique was not feasible in conventional machining centers. In this work, these matters were tackled and the possibility of using SAM in these five-axis centers with emulsion coolants was achieved. To verify this approach, Inconel 718 single blades with non-ruled surfaces were manufactured with Flank-SAM technique and conventional milling process, analyzing cutting forces, surface roughness, and dimension accuracy in both cases. The results show that SAM implies a suitable, controllable, and predictable process to improve the manufacture of aeronautical critical components, such as IBR.FEDE

Modularity of Production Systems

From the theoretical point of view, the chapter focuses on the unification of views on the living (constantly changing) structure of the construction of flexible production systems, including its cooperating devices. It contains currently defined and designated technical terms in the field of flexible production systems. From the theoretical point of view, the existing structures of the “multiprofessional manufacturing robotic center” are enhanced with new elements, which also contributes to innovation and expansion of their applications. These structural structures served as the basis for building sophisticated modular structures. Modularity is an integrating element directed at highly customizable manufacturing engineering structures. It fully complies with the requirements of manufacturing practice and demanding market, in the framework of fully implemented Industry 4.0 (I4.0) under way

On-machine identification of rotary axis location errors under thermal influence by spindle rotation

Position and orientation errors of rotary axis average lines are often among dominant error contributors in the five-axis kinematics. Although many error calibration schemes are available to identify them on -machine, they cannot be performed when a machine spindle is rotating. Rotary axis location errors are often influenced by the machine’s thermal deformation. This paper presents the application of a non-contact laser light barrier system, widely used in the industry for tool geometry measurement, to the identification of rotary axis location errors, when the spindle rotates in the same speed as in actual machining applications. The effectiveness of the proposed scheme is verified by experimental comparison with the R-Test and a machining test. The uncertainty analysis is also presented.This work was supported by JSPS KAKENHI Grant NumberJP15K05721

Kinematic analysis and optimization of robotic milling

Robotic milling is proposed to be one of the alternatives to respond the demand for flexible and cost-effective manufacturing systems. Serial arm robots offering 6 degrees of freedom (DOF) motion capability which are utilized for robotic 5-axis milling purposes, exhibits several issues such as low accuracy, low structural rigidity and kinematic singularities etc. In 5-axis milling, the tool axis selection and workpiece positioning are still a challenge, where only geometrical issues are considered at the computer-aided-manufacturing (CAM) packages. The inverse kinematic solution of the robot i.e. positions and motion of the axes, strictly depends on the workpiece location with respect to the robot base. Therefore, workpiece placement is crucial for improved robotic milling applications. In this thesis, an approach is proposed to select the tool axis for robotic milling along an already generated 5-axis milling tool path, where the robot kinematics are considered to eliminate or decrease excessive axis rotations. The proposed approach is demonstrated through simulations and benefits are discussed. Also, the effect of workpiece positioning in robotic milling is investigated considering the robot kinematics. The investigation criterion is selected as the movement of the robot axes. It is aimed to minimize the total movement of either all axes or selected the axis responsible of the most accuracy errors. Kinematic simulations are performed on a representative milling tool path and results are discusse

Fabrication of a Small Scale Model of Chancellor Award Trophy using CAD/CAM and CNC Milling Machine

The Final Year Project (FYP) is to manufacture a small scale model of Chancellor Award Trophy using Computer Aided Design (CAD)/ Computer Aided Manufacturing (CAM) and Computer Numerical Control (CNC) milltng. The main purpose of the project is to manufacture the model by utilizing the tools and machine provided in UTP. The objectives of this project are to create 2D and 3D model (CAD) drawing of the model, to define tool path for NC codes development (CAM) and to fabricate the model using CNC milling machine (CAM). Clear and sufficient understanding of CAD/CAM process and software is needed in order to create 2D and 3D drawing thus to generate NC codes for manufacturing. The methodology involve in this project are studying and research on CAD/CAM component and familiarization on Unigraphics NX software. Next is to come up with the 2D drafting and 3D solid model drawing of the model using Unigraphics NX software. Then, overall shape and dimension of the part from the drawing will be used to define tool path to allow the Unigraphics NX software to generate the coding for CNC machining. The end results of this project are; i) 2D drafting and 3D solid model drawing, ii) Tool path, iii) NC codes, iv) Small scale model of the trophy