2. Shear & Friction Zones and Different Force Components
Shear Zone Fs
Ff
Fn
N
Friction Zone
Fc
Ft
ď Cutting Force (Fc): Acts in the
direction of cutting speed and
parallel to the work piece surface
and supplies energy required for
cutting.
ď Thrust Force or Tangential Force
(Ft): Acts in a direction normal to
the cutting velocity, that is
perpendicular to the work piece
surface.
Dr. Jayanta Kr. Mahato, Asst. Prof., Mechanical Engineering
31. Solution of Merchantâs Circle Diagram
R
R/
A
Q
B
P
L M N
Fc
Ft
Fn
Fs
Ff
N
R a
a
Ď
Ď
a
Fc = AS + SR/
Fc = Fn sinĎ + Fs cosĎ 1
Ft = OB - AB
Ft = Fn cosĎ - Fs sinĎ 2
32. Solution of Merchantâs Circle Diagram
R
R/
A
Q
B
P
L M N
Fc
Ft
Fn
Fs
Ff
N
R a
a
Ď
Ď
a
Ft = AL â OL
Ft = R/N - OL
Ft = Ff cosa - N sina 3
Fc = LM + MN
Ft = Ff sinja + N cosa 4
33. Calculation of Forces from Merchantâs Circle Diagram
Dr. Jayanta Kr. Mahato, Asst. Prof., Mechanical Engineering
34. Solution of Merchantâs Circle Diagram
Dr. Jayanta Kr. Mahato, Asst. Prof., Mechanical Engineering
35. Need of Analysis of Forces
Dr. Jayanta Kr. Mahato, Asst. Prof., Mechanical Engineering
39. Home Assignment
following
ď Derive the
different machining
force relationships
from Merchantâs Circle
Diagram shown in the
figure.
Dr. Jayanta Kr. Mahato, Asst. Prof., Mechanical Engineering