CONTENTS
EXPERIMENT 1 .................................................................................................................................... 1
MACHINE TOOLS AND MACHINING PROCESS .............................................................................. 1
EXPERIMENT NO. 2 ............................................................................................................................. 4
CUTTING TOOL MATERIALS IN CUTTING OPERATION................................................................ 4
EXPERIMENT 3 .................................................................................................................................... 8
EFFECT OF WORKPIECE MATERIAL ON CHIP FORMATION ........................................................ 8
EXPERIMENT 4 .................................................................................................................................. 11
DETERMINATION OF CUTTING RATIO AND SHEAR ANGLE ..................................................... 11
EXPERIMENT NO. 5 ........................................................................................................................... 14
GRINDING WHEEL AND TOOL DRILL NOMENCLATURE ........................................................... 14
EXPERIMENT 6 .................................................................................................................................. 18
ANGULAR MEASUREMENT WITH TOOL MAKER MICROSCOPE ............................................... 18
EXPERIMENT 7 .................................................................................................................................. 21
MEASUREMENT OF CUTTING FORCES USING TOOL FORCE DYNANOMETER ...................... 21
1
, EXPERIMENT 1
MACHINE TOOLS AND MACHINING PROCESS
AIM:
To study the selected machine tools and machining processes.
THEORY:
Machining
Machining is a process designed to change the size, shape and surface of a
material through removal of materials that could be achieved by straining the
material to fracture or by thermal evaporation.
Importance of machining
i. Excellent dimensional tolerances
-Example is forged crankshaft where holes and bearing surfaces
require tight tolerances.
ii. External and internal geometrical features
-Sharp corners, grooves, fillets, various geometry
iii. Surface finish
-Example is a copper mirror by diamond turning
iv. Removal of heat treat distortion
-Parts such as crank and camshafts undergo distortion during heat
treatment.
Machining is a process for “straightening” the parts.
v. Economical if small quantities.
Constituents of machining system
A machining system consists of three components:
i. machine tool
ii. cutting tool
iii. work piece
Fundamental machine parameters
Cutting Tool Material: In metal-cutting, High Speed steel and Carbide are
two major tool materials widely used.
1
, Cutting speed (V): is the largest of the relative velocities of cutting tools or
work piece. In turning, it is the speed of the work piece while in drilling and
milling it is the speed of the cutting tool. In turning, it is given by the surface
speed of the work piece, V=nD1N where D1 is the diameter of the work
piece.
Depth of cut: It indicates how much the tool digs into the component (in mm)
to remove material in the current pass.
Feed rate: The relative speed at which the tool is linearly traversed over the
workpiece to remove the material. In case of rotating tools with multiple
cutting teeth (like a milling cutter), the feed rate is first reckoned in terms of
“feed per tooth,” expressed in millimeters (mm/tooth). At the next stage, it is
“feed per revolution” (mm/rev).
Tool geometry: For the tool to effectively dig into the component to remove
material most efficiently without rubbing, the cutting tool tip is normally
ground to different angles (known as rake angle, clearance angles, relief
angle, approach angle, etc.).
Coolant: To take away the heat produced in cutting and also to act as a
lubricant in cutting to reduce tool wear, coolants are used in metal-cutting.
Coolants can range from cutting oils, water-soluble oils, oil-water spray, and
so on.
Various Types of Machining Operations
2
EXPERIMENT 1 .................................................................................................................................... 1
MACHINE TOOLS AND MACHINING PROCESS .............................................................................. 1
EXPERIMENT NO. 2 ............................................................................................................................. 4
CUTTING TOOL MATERIALS IN CUTTING OPERATION................................................................ 4
EXPERIMENT 3 .................................................................................................................................... 8
EFFECT OF WORKPIECE MATERIAL ON CHIP FORMATION ........................................................ 8
EXPERIMENT 4 .................................................................................................................................. 11
DETERMINATION OF CUTTING RATIO AND SHEAR ANGLE ..................................................... 11
EXPERIMENT NO. 5 ........................................................................................................................... 14
GRINDING WHEEL AND TOOL DRILL NOMENCLATURE ........................................................... 14
EXPERIMENT 6 .................................................................................................................................. 18
ANGULAR MEASUREMENT WITH TOOL MAKER MICROSCOPE ............................................... 18
EXPERIMENT 7 .................................................................................................................................. 21
MEASUREMENT OF CUTTING FORCES USING TOOL FORCE DYNANOMETER ...................... 21
1
, EXPERIMENT 1
MACHINE TOOLS AND MACHINING PROCESS
AIM:
To study the selected machine tools and machining processes.
THEORY:
Machining
Machining is a process designed to change the size, shape and surface of a
material through removal of materials that could be achieved by straining the
material to fracture or by thermal evaporation.
Importance of machining
i. Excellent dimensional tolerances
-Example is forged crankshaft where holes and bearing surfaces
require tight tolerances.
ii. External and internal geometrical features
-Sharp corners, grooves, fillets, various geometry
iii. Surface finish
-Example is a copper mirror by diamond turning
iv. Removal of heat treat distortion
-Parts such as crank and camshafts undergo distortion during heat
treatment.
Machining is a process for “straightening” the parts.
v. Economical if small quantities.
Constituents of machining system
A machining system consists of three components:
i. machine tool
ii. cutting tool
iii. work piece
Fundamental machine parameters
Cutting Tool Material: In metal-cutting, High Speed steel and Carbide are
two major tool materials widely used.
1
, Cutting speed (V): is the largest of the relative velocities of cutting tools or
work piece. In turning, it is the speed of the work piece while in drilling and
milling it is the speed of the cutting tool. In turning, it is given by the surface
speed of the work piece, V=nD1N where D1 is the diameter of the work
piece.
Depth of cut: It indicates how much the tool digs into the component (in mm)
to remove material in the current pass.
Feed rate: The relative speed at which the tool is linearly traversed over the
workpiece to remove the material. In case of rotating tools with multiple
cutting teeth (like a milling cutter), the feed rate is first reckoned in terms of
“feed per tooth,” expressed in millimeters (mm/tooth). At the next stage, it is
“feed per revolution” (mm/rev).
Tool geometry: For the tool to effectively dig into the component to remove
material most efficiently without rubbing, the cutting tool tip is normally
ground to different angles (known as rake angle, clearance angles, relief
angle, approach angle, etc.).
Coolant: To take away the heat produced in cutting and also to act as a
lubricant in cutting to reduce tool wear, coolants are used in metal-cutting.
Coolants can range from cutting oils, water-soluble oils, oil-water spray, and
so on.
Various Types of Machining Operations
2
