A Tool Deflection Compensation System for End Milling Accuracy Improvement

1998 ◽  
Vol 120 (2) ◽  
pp. 222-229 ◽  
Author(s):  
M. Y. Yang ◽  
J. G. Choi

In an effort to reduce machining surface errors due to tool deflection in the end milling process, methods regulating cutting forces have been implemented with online feed rate controls. Such schemes are able to improve the parts dimensional accuracy, but unfortunately they can exhibit undesirable aspects in which the alleviation of the cutting conditions deteriorates the productivity. In addition the frequent changes of the feed rate would spoil the surface quality. As a new approach to achieve the precision machining efficiently, this paper introduces a tool deflection compensation system. This compensation system is a computer controlled special tool adapter which is capable of measuring the cutting forces and minutely adjusting the position of the tool without interfacing with the NC controller of the milling machine. Such a system allows for on-line estimation of the tool deflections and reduction of the surface errors. Experimental investigations for typical shaped workpieces representing various end milling situations are performed to verify the ability of the system to suppress the surface errors due to tool deflections in more productive machining condition.

2014 ◽  
Vol 1019 ◽  
pp. 318-324
Author(s):  
Jean Claude Fwamba ◽  
Lerato Crescelda Tshabalala ◽  
Cebo Philani Ntuli ◽  
Isaac Tlhabadira

<span><p align="LEFT"><span><span style="font-family: Times New Roman;" face="Times New Roman">Titanium and its alloys have been experiencing extensive development over the past few decades. They have found wide applications in the aerospace, biomedical and automotive industries owing to their good strength-to-weight ratio and high corrosion resistance. Machining performance is often limited by chatter vibrations at the tool-workpiece interface. Chatter is an abnormal tool behaviour which is one of the most critical problems in the machining process and must be avoided to improve the dimensional accuracy and surface quality of the finished product. This research aims at investigating chatter trends in the end milling process and to identify machine parameters that have effects on chatter during machining. The machine parameters investigated include axial feed rate, spindle revolute speed and depth of cut. In this research, experimental data was collected using sensors to analyze the existence of chatter vibrations on each processing condition. This research showed that the combination of the machine parameters, feed rate and spindle speed within certain proportions has an influence on machine vibrations during end milling and if not managed properly, may lead to chatter. </span></span></p> <p align="LEFT"></p>


2011 ◽  
Vol 328-330 ◽  
pp. 560-564
Author(s):  
Ba Sheng Ouyang ◽  
Guo Xiang Lin ◽  
Yong Hui Tang

Cutting forces and machining error in contouring of concave and convex surfaces using helical ball end mills are theoretically investigated. The cutting forces are evaluated based on the theory of oblique cutting. The machining errors resulting from the tool deflections due to these forces are evaluated at various points of the machined surface. The influence of various cutting conditions and cutting modes on machining error is investigated and discussed.


Author(s):  
Xuewei Zhang ◽  
Tianbiao Yu ◽  
Wanshan Wang

An accurate prediction of cutting forces in the micro end milling, which is affected by many factors, is the basis for increasing the machining productivity and selecting optimal cutting parameters. This paper develops a dynamic cutting force model in the micro end milling taking into account tool vibrations and run-out. The influence of tool run-out is integrated with the trochoidal trajectory of tooth and the size effect of cutting edge radius into the static undeformed chip thickness. Meanwhile, the real-time tool vibrations are obtained from differential motion equations with the measured modal parameters, in which the process damping effect is superposed as feedback on the undeformed chip thickness. The proposed dynamic cutting force model has been experimentally validated in the micro end milling process of the Al6061 workpiece. The tool run-out parameters and cutting forces coefficients can be identified on the basis of the measured cutting forces. Compared with the traditional model without tool vibrations and run-out, the predicted and measured cutting forces in the micro end milling process show closer agreement when considering tool vibrations and run-out.


2004 ◽  
Vol 127 (3) ◽  
pp. 454-462 ◽  
Author(s):  
Liuqing Yang ◽  
Richard E. DeVor ◽  
Shiv G. Kapoor

This paper proposes an analytical approach to detect depth-of-cut variations based on the cutting-force shape characteristics in end milling. Cutting forces of a single-flute end mill are analyzed and classified into three types according to their shape characteristics. Cutting forces of a multiple-flute end mill are then classified by considering both the cutting types of the corresponding single-flute end mill and the degree of overlap of successive flutes in the cut. Force indices are extracted from the cutting forces and depth-of-cut variations are detected based on the changes of the force shape characteristics via the force indices in an end-milling process. The detection methodology is validated through cutting experiments.


2011 ◽  
Vol 188 ◽  
pp. 404-409 ◽  
Author(s):  
Xue Yan ◽  
Hua Tao ◽  
D.H. Zhang ◽  
B.H. Wu

A developed method to predict the cutting forces in end milling of generalized corners is proposed in this paper. The cornering milling process is divided into a series of cutting segments with different cutting states. The mathematical model of the geometric relationship between cutter and the corner profile is established for each segment. Cutting forces is predicted by introducing the classical cutting force model. The computational results of cutting forces are in good agreement with experimental data.


2014 ◽  
Vol 80 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Kazuo KASAHARA ◽  
Kentaro OHTAKA ◽  
Shoichi ITO ◽  
Akihiko HIROTA

Author(s):  
Akhil C. Kuriakose ◽  
Raman Balakrishnan ◽  
Harsh Vardhan ◽  
Krishnaraju Srinivasaraju Vijay Sekar

Super-alloys encompass great challenges in machinability. One such alloy of much interest in applications is Inconel 718. Its increased hardness, low thermal diffusivity and high temperature strength make it desirable for applications, at the same time rendering its machining a demanding task. Extensive studies have been performed on machinability of Inconel 718, from the turning process stand-point. However, there is found to be a comparative dearth of work on the milling process. Taking into account the versatility of end-milling within the family of milling processes and the research gap, we found that a parametric optimization (aimed at minimum machining forces) of end-milling would be a meaningful effort. An experiment was conducted to study conditions that would help us achieve the same. In our further quest for optimization, chip morphology studies using SEM occupied a special place. Bearing in mind immense prediction capabilities of computer simulations based on FEA available today, we attempted process replication of the experimental work. The significant cutting forces were chosen as the benchmark factor for this purpose and proper attention was given to validation of the FEM created. Such FEM holds promise of being resourceful to drive up efficiency, with consequent spill-over to the production line.


Author(s):  
Manoj Kumar

Analysis and simulation of manufacturing process require extensive and complicated computations. Nowadays, computer resources and computational algorithms reach to the state that can model and simulate the problem efficiently. One of the important processes in manufacturing is machining. In this research end-milling process which is one of the complex and wide-spread processes in machining is chosen. Most important parameters in end-milling are surface roughness and surface location errors. A comprehensive simulation software is developed to model end-milling process in order to anticipate finishing parameter such as surface roughness and errors. The proposed algorithm takes into account cutting conditions, such as feed, doc, woc, tool run out, etc. In addition, dynamic simulation module of the software can accurately model flexible end-mill tool, the milling cutting forces and regeneration of waviness effects. The software can accurately determine the most commonly used index of surface roughness parameters such as Ra, P.T.V. and surface errors.


Sign in / Sign up

Export Citation Format

Share Document