MEASUREMENT AND OPTIMIZATION OF DRILLING
100190119001 Rahul Bhat
100190119010 Hardik Thummar
Prof. N. H. PRAJAPATI
Drilling is a process of making hole or enlarge a
hole in an object by forcing a rotating tool called
a drill is cutting it has to overcome the
resistance offered by the metal and a twisting effort
is necessary to turn it. The torque required to
operate the drill is dependent upon various factors,
but for most of the practical purposes, the relation
between the torque, the diameter of drill and the
feed has found to be most satisfactory, based on
DRILLING PROCESS PARAMETERS
Depth of cut
Tolerance of holes
WHY PARAMETERS MEASURMENT AND
Real time optimization of drilling process
parameters during drilling operation for obtaining
maximum drilling rate as well as minimum drilling
cost, to get high productivity and high MRR by
changing process parameters such as drilling
diameters, cutting speed and feed rate.
For also improve drilling performance like tool life,
material removal rate.
AFFECT OF PARAMETERS
The relationships between the cutting force signals
and drill wear as well as other cutting parameters
including spindle rotational speed, feed rate and
drill diameter were established by lots of
The tool wear can be estimated knowing the thrust
force, feed per revolution and drill diameter.
The temperature of cutting edge increases with the
increase of spindle speed (cutting speed) and feed
coolant can perform roll for reduction tool temperature,
thrust force, surface roughness.
Amount of metal remove is function of speed and feed.
Feed is varies from 0.05mm to 0.35mm per revolution
and it’s variation is depends on hard and soft material.
Wear is thought to occur from chemical reactions in the
contact zone between the tool and the work piece.
Precise measurements of tool dimensions indicated that
the wear was concentrated at the tool center region and
at the intersection between the conical and cylindrical
The cutting speed in a drilling operation refers to the peripheral speed of a point
on the surface of the drill in contact with the work. The cutting speed (v) may be
calculated as :
v=(pi*d*n)/1000 m per minute.
d is the diameter of the drill in mm
n is the rpm of the drill spindle.
The feed of a drill is the distance the drills moves into the work at each revolution
of the spindle. It is expressed in mm. the feed may also be expressed as feed
per minute. The feed per minute may be defined as the axial distance moved by
the drill into the work per minute. The feed per minute may be calculated as:
Sm = sr × n
Sm = feed per minute in mm.
Sr = fee per revolution in mm.
n = rpm of the drill.
Depth of cut:
The depth of cut in drilling is equal to one half of the drill diameter. The depth of
cut (t) may be expressed as :
t =D/2 mm
Machining timing in drilling:
T=L/(n* Sr ) min.
n = r.p.m of the drill
Sr = feed per revolution of the drill in mm.
L = length of the travel of the drill in mm.
T = machining time in min.
L = l1 + l 2 + l 3 + l 4
l1 = length of the work piece
l2 = approach of the drill,
l3 = length of the drill point (0.29d),
l4 = over travel
As per availability of measuring instruments which
is required for parameters measurement We have
to do experimental investigation for drilling process
and optimization it’s parameters.
Force, torque, Feeds rate, Spindle Speed, Cutting
speed, power supply.
Taguchi method is utilize while investigation for
higher precision at lower experimental operations in
THE TAGUCHI PROCESS
• Noise [N]: It is the set of uncontrolled parameters
which influence the final result or response
Example: Environmental Condition, Human Interface
• Signal [S]: It is the output variable or response
Example: Final output of result of an experiment or
Magnitude of Response Variable for each experiment
• Signal to Noise Ratio [S/N]: This indicates
robustness of an experiment. It consolidates
several repetitions [at least two data points] into
one value that reflects the amount of variation
By Hajara Chaudhary 13th edition
By R. K. Jain, Khanna publication 16th edition
Design Of Experiment
BY Dr. S. A. Chaniwala
S.C. Lin and , C.J. Ting(Tool wear monitoring in
drilling using force signals)
T. Ueda, R. Nozaki and A. Hosokawa(Temperature
Measurement of Cutting Edge in Drilling)
Scott F. Millera, Peter J. Blaub, Albert J. Shiha,(Tool
wear in friction drilling)