The paper presents a methodology to model the cutting forces by twist drills with generic point geometry. A generic definition of point geometry implies that the cutting lips and the relief surfaces can have arbitrary shapes. Such geometry is easily modeled using Non Uniform Rational B-Spline (NURBS) surface patches which give sufficient freedom to the tool designer to alter the tool geometry. The drill point has three cutting zones: primary cutting lips, secondary cutting lips, and the indentation zone at the center of chisel edge. At the indentation zone, the drill extrudes the workpiece, while at the cutting lips, shearing takes place. At primary cutting lip, the cutting is oblique while at secondary cutting lip, it is predominantly orthogonal. Starting from a computer-aided geometric design of a fluted twist drill with arbitrary point profile, the cutting forces have been modeled separately for all the three cutting zones. The mechanistic method has been employed wherever applicable to have a good correlation between the analytical and the experimental results. The force model has been calibrated and validated for conical drills. Then the model has been evaluated for a drill ground with curved relief surfaces. The theoretical and experimental results are found out to be in good conformity.

References

References
1.
Ehmann
,
K. F.
,
Kapoor
,
S. G.
,
DeVor
,
R. E.
, and
Lazoglu
,
L.
,
1997
, “
Machining Process Modeling: A Review
,”
ASME J. Manuf. Eng.
,
119
, pp.
655
663
.10.1115/1.2836805
2.
Armarego
,
E. J. A.
, and
Cheng
,
C. Y.
,
1972
, “
Drilling With Flat Rake Face and Conventional Twist Drills. I—Theoretical Investigations and II—Experimental Investigations
,”
Int. J. Mach. Tool Des. Res.
,
12
, pp.
17
54
.10.1016/0020-7357(72)90009-1
3.
Armarego
,
E. J. A.
, and
Wright
,
J. D.
,
1984
, “
Predictive Models for Drilling Thrust and Torque—A Comparison of Three Flank Configurations
,”
Ann. CIRP
,
33
(
1
), pp.
5
10
.10.1016/S0007-8506(07)61368-7
4.
Rubeinstein
,
C.
,
1991
, “
The Torque and Thrust Force in Twist Drilling. I—Theory and II—Comparison of Experimental Observations and Deductions From Theory
,”
Int. J. Mach. Tools Manuf.
,
31
(
4
), pp.
481
504
.10.1016/0890-6955(91)90031-W
5.
Watson
,
A. R.
,
1985
, “
Drilling Model for Cutting Lip and Chisel Edge and Comparison of Experimental and Predicted Results. I—Initial Cutting Lip Model, II—Revised Cutting Lip Model, III—Drilling Model for Chisel Edge, IV—Drilling Tests to Determine Chisel Edge Contribution to Thrust and Torque
,”
Int. J. Mach. Tool Des. Res.
,
25
(
4
), pp.
347
404
.10.1016/0020-7357(85)90035-6
6.
Stephenson
,
D. A.
, and
Agapiou
,
J. S.
,
1992
, “
Calculation of Main Cutting Edge Forces and Torque for Drills With Arbitrary Point Geometries
,”
Int. J. Mach. Tools Manuf.
,
32
, pp.
521
538
.10.1016/0890-6955(92)90043-G
7.
Chandrasekharan
,
V.
,
Kapoor
,
S. G.
, and
DeVor
,
R. E.
,
1995
, “
A Mechanistic Model to Predict the Cutting Forces in Drilling: With Application to Fiber Reinforced Composite Materials
,”
ASME J. Eng. Ind.
,
117
, pp.
559
570
.10.1115/1.2803534
8.
Abelein
,
O.
,
1998
, “
Enhancement of the Mechanistic Force Model in Drilling
,” M.S. thesis., University of Illinois, Urbana Champaign (UIUC).
9.
Paul
,
A.
,
Kapoor
,
S. G.
, and
DeVor
,
R. E.
,
2005
, “
Chisel Edge and Cutting Lip Shape Optimization for Improved Twist Drill Point Design
,”
Int. J. Mach. Tools Manuf.
,
45
, pp.
421
431
.10.1016/j.ijmachtools.2004.09.010
10.
Lazar
,
M. B.
, and
Xirouchakis
,
P.
,
2013
, “
Mechanical Load Distribution Along the Main Cutting Edges in Drilling
,”
J. Mater. Process. Technol.
,
213
, pp.
245
260
.10.1016/j.jmatprotec.2012.09.020
11.
Sui
,
J.
,
Sugita
,
N.
,
Ishii
,
K.
,
Harada
,
K.
, and
Mitsuishi
,
M.
,
2014
, “
Mechanistic Modeling of Bone-Drilling Process With Experimental Validation
,”
J. Mater. Process. Technol.
,
214
, pp.
1018
1026
.10.1016/j.jmatprotec.2013.11.001
12.
Sambhav
,
K.
,
Tandon
,
P.
, and
Dhande
,
S. G.
,
2012
, “
Geometric Modeling and Validation of Twist Drills With a Generic Point Profile
,”
Appl. Math. Model.
,
36
, pp.
2384
2403
.10.1016/j.apm.2011.08.034
13.
Sambhav
,
K.
,
Tandon
,
P.
, and
Dhande
,
S. G.
,
2010
, “
CAD Based Mechanistic Modeling of Forces for Generic Drill Point Geometry
,”
Comput. Aided Des. Appl.
,
7
(
6
), pp.
809
819
.10.3722/cadaps.2010.809-819
14.
Oxford
,
C. J.
, Jr.
,
1955
, “
On the Drilling of Metals–1. Basic Mechanics of the Process
,”
Trans. ASME
,
77
, pp.
103
114
.
15.
Shaw
,
M. C.
, and
Oxford
,
C. J.
, Jr.
,
1957
, “
On the Drilling of Metals 2–The Torque and Thrust in Drilling
,”
Trans. ASME
,
79
(
1
), pp.
142
148
.
16.
Mauch
,
C. A.
, and
Lauderbaugh
,
L. K.
,
1990
, “
Modeling the Drilling Process—An Analytical Model to Predict Thrust Force and Torque
,” Computer Modeling and Simulation of Manufacturing Processes, ASME PED, p.
48
.
17.
Hill
,
R.
,
Lee
,
E. H.
, and
Tupper
,
S. J.
,
1947
, “
The Theory of Wedge Indentation of Ductile Materials
,”
Proc. R. Soc. London, A
,
188
, pp.
273
290
.10.1098/rspa.1947.0009
18.
Kachanov
,
L. M.
,
2004
,
Foundations of the Theory of Plasticity
,
North-Holland Publishing Company
,
Amsterdam
, The Netherlands, pp.
129
139
.
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