Analysis of Oblique Cutting Forces

1967 ◽  
Vol 89 (2) ◽  
pp. 347-355 ◽  
Author(s):  
Russell F. Henke

This paper is the latest of a continuing series on the subject of self-excited machine tool chatter. The representation of the metal cutting process as required by the previously developed closed-loop chatter theory is extended to oblique cutting with tools of practical shape and geometry. The cutting process parameters essential to proper application of the stability theory are found by an analytical formulation leading to a classical eigenvalue problem. Techniques are developed to determine the steady-state constant of proportionality between resultant cutting force and uncut chip area, the direction of resultant cutting force, and the direction of maximum cutting stiffness for any single-point cutting operation. In the process, a general method to predict steady-state oblique cutting forces is evolved. The method depends on certain experimentally justifiable assumptions and utilizes previously compiled orthogonal cutting data.

2015 ◽  
Vol 727-728 ◽  
pp. 335-338 ◽  
Author(s):  
Song Jie Yu ◽  
Di Di Wang ◽  
Xin Chen

Cutting process is a typical non-linear deformation problem, which involves material non-linear, geometry non-linear and the state non-linear problem. Based on the elastic-plastic material deformation theory, this theme established a strain hardening model. Build the simulation model of two-dimensional orthogonal cutting process of workpiece and tool by the finite element method (FEM), and simulate the changes of cutting force and the process of chip formation in the machining process, and analyzed the cutting force, the situation of chip deformation. The method is more efficient and effective than the traditional one, and provides a new way for metal cutting theory, research of material cutting performance and cutting tool product development.


1998 ◽  
Vol 120 (1) ◽  
pp. 49-56 ◽  
Author(s):  
B. K. Ganapathy ◽  
I. S. Jawahir

The present tendency towards increased automation of metal cutting operations has resulted in a need to develop a model for the chip breaking process. Conventional cutting force models do not have any provision for the study of chip breaking since they assume a continuous mode of chip formation, where the contact action of the free-end of the chip is ignored in all analyses. The new cutting force model proposed in this work incorporates the contact force developed due to the free-end of the chip touching the workpiece, and is applicable to the study of two-dimensional chip breaking in orthogonal machining. Orthogonal cutting tests were performed to obtain two-dimensional chip breaking. The experimentally measured cutting forces show a good correlation with the estimated cutting forces using the model. Results show that the forces acting on the chip vary within a chip breaking cycle and help identify the chip breaking event.


2010 ◽  
Vol 97-101 ◽  
pp. 1961-1964 ◽  
Author(s):  
Wei Guo Wu ◽  
Gui Cheng Wang ◽  
Chun Gen Shen

In this work, the prediction and analysis of cutting forces in precision turning operations is presented. The model of cutting forces is based on the oblique cutting force model which was rebuilt by two coordinate conversions from the orthogonal cutting model. Then the cutting field in precision turning was divided into two fields which are characterized as curve change and linear change on cutter edge and they were modeled respectively. Cutting field of cutter nose was modeled by differential method and its cutting force distribution is predicted by the proposed method. The predicted results for the cutting forces are in agreement with the experimental results under a variety of operation variables, including changes in the depths of cut and in the feedrate.


1978 ◽  
Vol 100 (1) ◽  
pp. 92-99
Author(s):  
N. Saravanja-Fabris ◽  
A. F. D’Souza

Chatter in metal cutting is a nonlinear self-excited vibration of the limit cycle type. This investigation is concerned with the analysis of chatter from the viewpoint of the describing function. Vibrations with different frequencies and amplitudes were superimposed on the steady feed motion of the tool in orthogonal cutting in order to simulate chatter. The relationships between the oscillating cutting and thrust forces and tool vibrations are discussed from the point of view of energy transfer and describing functions. Experimentally obtained describing functions of the dynamically varying cutting process are given. The stability of a typical machine tool structure under primary chatter conditions with dynamical cutting process represented by its describing function is discussed.


Author(s):  
Zoltan Dombovari ◽  
R. Eddie Wilson ◽  
Gabor Stepan

The classical model of regenerative vibration is investigated with new kinds of nonlinear cutting force characteristics. The standard nonlinear characteristics are subjected to a critical review from the nonlinear dynamics viewpoint based on the experimental results available in the literature. The proposed nonlinear model includes finite derivatives at zero chip thickness and has an essential inflexion point. In the case of the one degree-of-freedom model of orthogonal cutting, the existence of unstable self-excited vibrations is proven along the stability limits, which is strongly related to the force characteristic at its inflexion point. An analytical estimate is given for a certain area below the stability limit where stable stationary cutting and a chaotic attractor coexist. It is shown how this domain of bistability depends on the theoretical chip thickness. The comparison of these results with the experimental observations and also with the subcritical Hopf bifurcation results obtained for standard nonlinear cutting force characteristics provides relevant information on the nature of the cutting force nonlinearity.


2014 ◽  
Vol 797 ◽  
pp. 47-52
Author(s):  
Jorge Salguero ◽  
Madalina Calamaz ◽  
Moisés Batista ◽  
Franck Girot ◽  
Mariano Marcos Bárcena

Cutting forces are one of the inherent phenomena and a very significant indicator of the metal cutting process. The work presented in this paper is an investigation of the prediction of these parameters in slotting processes of UNS A92024-T3 (Al-Cu) stacks. So, cutting speed (V) and feed per tooth (fz) based parametric models, for experimental components of cutting force, F(fz,V) have been proposed. These models have been developed from the individual models extracted from the marginal adjustment of the cutting force components to each one of the input variables: F(fz) and F(V).


2010 ◽  
Vol 139-141 ◽  
pp. 917-920
Author(s):  
Wei Guo Wu ◽  
Gui Cheng Wang ◽  
Chun Gen Shen

In this work, the prediction and analysis of cutting forces in helical ball-end milling operations is presented. The cutting forces model for helical end-mills is based on the oblique cutting theory and the geometric relations of the ball-end milling process. The helical flutes are divided into small differential oblique cutting edge segments. According to the transformation relationship between the local and global coordinate system of the cutter, the differential cutting force of cutting element is obtained by two coordinate conversions from the orthogonal cutting force. The total cutting force of helical ball-end milling is the sum of the cutting force in whole cutting field of the miller. As a result, the predicted cutting forces show an agreement with the values from the cutting experiments.


2006 ◽  
Vol 5-6 ◽  
pp. 367-374
Author(s):  
C. G. Dumitraş

Due to robotic deburring development, the research gains a new orientation and focused on the cutting forces and the chip control. The present paper will emphasize the main difference which occurs between the normal cutting process and the deburring process, the way it develops and the parameters which characterize this process. Also the dynamics of the process are considered. Based on a central composite design one determine a relation between the geometry of the tool, workpiece hardness and cutting force.


Author(s):  
Ashwani Pratap ◽  
Karali Patra

Abstract This work presents an analytical cutting force modeling for micro-slot grinding. Contribution of the work lies in the consideration of both primary and secondary tool surface interactions with the work surface as compared to the previous works where only primary tool surface interaction was considered during cutting force modeling. Tool secondary surface interaction with workpiece is divided into two parts: cutting/ ploughing by abrasive grits present in exterior margin of the secondary tool surface and sliding/adhesion by abrasive grits in the inner margins of the secondary tool surface. Orthogonal cutting force model and indentation based fracture model is considered for cutting by both the abrasives of primary tool surface and the abrasives of exterior margin on the secondary surface. Asperity level sliding and adhesion model is adopted to solve the interaction between the workpiece and the interior margin abrasives of secondary tool surface. Experimental measurement of polycrystalline diamond tool surface topography is carried out and surface data is processed with image processing tools to determine the tool surface statistics viz., cutting edge density, grit height distribution and abrasive grit geometrical measures. Micro-slot grinding experiments are carried out on BK7 glass at varying feed rate and axial depths of cut to validate the simulated cutting forces. Simulated cutting forces considering both primary and secondary tool surface interactions are found to be much closer to the experimental cutting forces as compared to the simulated cutting forces considering only primary tool surface interaction.


2019 ◽  
Vol 945 ◽  
pp. 556-562
Author(s):  
A.G. Kondrashov ◽  
D.T. Safarov ◽  
R.R. Kazargeldinov

Minimizing energy consumption in the processing of parts on metal-cutting equipment is most effective at the stage of designing the content of operations. Important in this process is the precise determination of the initial parameters - cutting forces. This parameter allows you to plan both energy consumption and perform additional calculations for the deformation of the tooling and workpiece in order to predict the geometric accuracy of the machined part. The article presents the results of experiments on measuring the circumferential cutting force during milling operations of an aluminum alloy workpiece with an end mill. The measurements were carried out by an indirect method - by recording the electrical power on the spindle and then calculating the circumferential cutting force. Theoretical analysis of the methods of calculation of cutting forces showed significant differences between the results obtained by domestic methods and recommendations of world manufacturers of cutting tools. Statistical analysis of the results of calculations based on reference data and measurements made it possible to assess the adequacy of the known methods for calculating cutting forces in order to minimize energy consumption in operations of processing parts on metal-cutting equipment


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