Development of Models for Predicting Some Surface Responses in Oblique Metal Cutting Using Mild Steel and Coated Carbide

Oblique metal cutting is a milling process which constitutes the work piece, tool piece, machine centre and the machinist or operator. This research has been able to obtain some responses such as tool life, and the surface roughness. Most machine elements fail due to some poor surface finish errors such as craters, waviness, flay and lay. Previous researchers have focused more on the absolute value of the surface roughness (Ra) and this cannot provide for all the errors encountered on surface texture. The primary aim of this research is to develop models that can predict the surface roughness of machine parts produced in oblique metal cutting above the absolute value of the average surface roughness and in turn provide a document or framework for machinist which can serve as a guide for machinist. The work has been able to determine a near perfect surface roughness for mild steel using coated carbide as tool piece as the models developed has minimized the effect of surface roughness at run 6, 6 and 8 for Ra, Rz and maximized TL in the values of 1.071408 micrometer, 2.668293 micrometer and 49837238 seconds respectively. Also. the analysis of variance performed has also shown that is proper to accept the analysis using a significance α level of 0.05.

Analysis of DMU40 machine centre by CAE software

This article is part of a longer research-analytical work, because it outlines the results and conclusions of the study according to the main topic of the research and the applied method. The central theme of the research is the dynamic stiffness of machine tools and the various methods for their determination. After analytical testing, we will deal with another method, because we also use CAE software (ANSYS Workbench R19.1) to perform previous tests in the form of simulations. The results obtained are compared with the values previously determined analytically.

Analysis of DMU40 machine centre by vibration measurement

This article is part of a longer research-analytical work, because it outlines the results and conclusions of the study according to the main topic of the research and the applied method. The central theme of the research is the dynamic stiffness of machine tools and the various methods for their determination. Following analytical analysis the machine tool natural frequencies were determined using a finite element software (ANSYS Workbench R19.1), which we now approach from a practical point of view, that is determined in the workshop by measurements. The results obtained are compared for each of the three methods.

Analysis of DMU40 machine centre by finite degrees of freedom

This article is part of a longer research-analytical work, because it outlines the results and conclusions of the study according to the main topic of the research and the applies method. The central theme of the research is the dynamic stiffness of machine tools and the various methods for their determination. The first such (finite element) method is modal analysis, which allows for an analytical test. The purpose of this article is to approach this study from the practical side through a specific example.

Interactive fixture and tool space design considering tool movement, machine, and inspection for five-axis grinding

This paper proposes a novel method of collision-free fixture and tool space design for five-axis grinding, considering tool movement, machine degrees of freedom, the machine envelope, inspection, and related features. The fixture space is designed in three steps. First, the fixture space is generated as the remaining space after cutting out the tooling space (i.e. the sweeping space of the grinding wheel along the profile of the machined features). In this way, the fixture space is naturally collision-free with respect to tool movement. Second, the fixture space is further modified based on the constraints imposed by the grinding machine centre, which include over-travel distance, the positions of coolant nozzle and wheel dresser, and so on. Third, the fixture space is modified again according to measurements conducted by coordinate measuring machines and in-cycle machine probes. Interactions of fixture space with tool space, machine, and inspection are considered. The fixture space design for holding aerofoil blades on a five-axis machining centre Makino A55 for grinding operations is used as a case study, and the results of this study have been verified by computer-aided manufacture (CAM) simulation software Vericut and physical experiments using dummy wheels.

New Approach to the Local Synthesis of Spiral Bevel Gears

The generating of two spiral bevel gears by the plane-top generating wheel with essentially different parameters of the head-cutter installation and motion is considered. For this case the necessary and sufficient conditions providing coincidence of normal vectors and surface curvatures in the designed point are presented as the vector equations system. The relations among blade pressure angle, head-cutter radius, radial distance, tool installation angle, machine centre to back, blank offset and velocity ratio are obtained. The developed methods make the opportunity to design equivalent machine-tool settings, to extend manufacturing possibilities of gear-cutting machines and to raise the load rating of the gear drive.

A genetic algorithm-based parameter-tuning algorithm for multi-dimensional motion control of a computer numerical control machine tool

This paper addresses an automatic parameter-tuning algorithm for the multi-axis motion control of a computer numerical control (CNC) machine centre. The traditional approach to tune the control parameters in the multi-axis machines is to tune each axis independently. Some high-end-precision machines offer cross-axis motion parameters for impedance compensation but this is usually not satisfactory for practical purpose. Because each axis on the machine centre contributes to more than one working plane, obtaining the optimal performance for motions involving more than one plane often results in axis coupling. This paper introduces a systematic method to tune the servo parameters for multi-axis motion control. The tuning algorithm is based upon an intelligent genetic algorithm (GA) and the parameters are tuned for each work plane. The method optimized the multi-axis motion performance. A modified GA is also proposed to solve the convergence problem induced by a large number of parameters in multi-axis motion tuning.