Introduction about CNC Machine

1. INTRODUCTION ABOUT CNC
MACHINE
PRESENTED BY
MOHAMMAD HUSSAIN
Assistant Professor, ME Dept.

2. CONTENTS
• Definition of CNC Machine
• Brief History and Evolution
• How CNC Machine Works
• Comparison CNC Machine with Traditional Machines
• Components of CNC Machines
• Overview of G-Code
• Overview of M-Code
• Types of CNC Machines
• Advantages , Disadvantages & Applications

3. DEFINITION OF
CNC MACHINE
• CNC stands for Computer Numerical
Control.
• CNC is a machine controlled by a
Computer.
• CNC is a manufacturing method that
automates the control, movement and
precision of machine tools through the
use of preprogrammed computer
software, which is embedded inside the
tools.

4. BRIEF HISTORY
AND EVOLUTION
 1950s-1960s: Early Developments
•The concept of numerical control (NC) originated
in the late 1940s.
•In the 1950s, the first rudimentary NC machines
were developed, primarily for military and
aerospace applications.
•John T. Parsons is often credited as the "Father of
the CNC Machine" for his work in developing
numerical control for machining aircraft parts.
 1970s: Emergence of CNC
•The term "Computer Numerical Control"
(CNC) came into use in the 1970s.
•The integration of computers into machine
control systems allowed for more
sophisticated and precise machining
operations.
•CNC machines became commercially
available, initially for milling and drilling
applications.

5. BRIEF HISTORY
AND EVOLUTION
 1990s: Integration of CAD/CAM
•The integration of Computer-Aided Design
(CAD) and Computer-Aided Manufacturing
(CAM) software became more prevalent in CNC
machining.
•This integration allowed for seamless design-to-
production workflows, enhancing precision and
reducing errors.
 2000s: High-Speed Machining and
Multi-Axis Systems
•High-speed machining became a focus,
enabling faster and more efficient cutting
processes.
•Multi-axis CNC machines became more
common, allowing for complex and intricate
machining operations.

6. BRIEF HISTORY
AND EVOLUTION
 2010s: Industry 4.0 and Smart
Manufacturing
•CNC machines played a crucial role in the Industry
4.0 revolution, which emphasizes connectivity,
automation, and data exchange in manufacturing.
•Smart CNC machines with advanced sensors and
data analytics capabilities became more prevalent,
contributing to predictive maintenance and
improved efficiency.
 2020s: Continued Innovation and
Integration
•CNC machines continue to evolve with
advancements in artificial intelligence, machine
learning, and robotics.
•Hybrid manufacturing, combining CNC machining
with technologies like 3D printing, gained
popularity for producing complex parts.

7. HOW CNC MACHINE
WORKS
CNC (Computer Numerical Control) machines operate based on a programmed set of
instructions to perform precise and automated machining tasks.
1. Designing the Part:
The process begins with the creation of a 3D model of the part using Computer-Aided Design
(CAD) software. This model defines the dimensions, geometry, and specifications of the final
product.
2. CAM Programming:
The CAD model is then converted into a set of instructions for the CNC machine using
Computer-Aided Manufacturing (CAM) software. CAM software generates toolpaths, which are
the routes the cutting tool will take to shape the part.
3. CNC Controller:
The CNC controller is the brain of the CNC machine. It interprets the programmed instructions
(G-code and M-code) and controls the movement of the machine components.

8. HOW CNC MACHINE
WORKS
4. Setup:
The machinist sets up the workpiece on the CNC machine, securing it to the worktable or
chuck. The cutting tools are also installed in the tool holder.
5. Homing and Calibration:
The CNC machine undergoes a homing sequence to establish its reference position.
Additionally, calibration processes ensure the accuracy and precision of the machine's
movements.
6. Tool Changes (if applicable):
For machining operations requiring multiple tools, the CNC machine may automatically or
manually change tools during the process.
7. Machining Operation:
The CNC machine follows the programmed toolpaths to remove material from the workpiece.
The movements are controlled in three or more axes (X, Y, Z, and sometimes additional
rotational axes in multi-axis machines).

9. HOW CNC MACHINE
WORKS
8. Feedback and Adjustments:
Feedback systems, such as encoders and sensors, continuously monitor the machine's position
and performance. This information is sent to the CNC controller, allowing for real-time
adjustments to ensure accuracy.
9. Coolant and Chip Management:
During machining, coolant is often used to dissipate heat generated by cutting and to lubricate
the cutting tool. Chip management systems remove chips and debris from the work area.
10. Quality Control:
After the machining process is complete, the machined part may undergo inspection using
metrology tools to ensure it meets the specified tolerances and quality standards.
11. Post-Processing:
Depending on the application, additional processes such as surface finishing or heat treatment
may be required.
12. Data Storage and Documentation:
The CNC program and associated data are typically stored for future use. Documentation may
include tooling information, machining parameters, and quality control data.

10. COMPARISON CNC MACHINES WITH
TRADITIONAL MACHINES
CNC MACHINE
• CNC machines can be used
continuously for long intervals.
• CNC machines can be updated
by using improved software to
drive the machines.
• One person can supervise
several CNC machines.
TRADITIONAL MACHINE
• They are difficult to operate for
long intervals.
• Chances for major improvement
in the same traditional machines
are very less.
• One person can not operate
more than one machine at a
time.

11. COMPONENTS OF
CNC MACHINE
1.Machine Control Unit:
• The brain of the CNC machine.
• It interprets the CNC code (G-code and M-
code) and converts it into electrical signals.
• Controls the movement and actions of the
machine components.
2. Drive System:
• Consists of motors and drive units.
• Motors provide the mechanical power
needed for the movement of different parts.
• Drive units amplify the control signals from
the CNC controller to drive the motors.

12. COMPONENTS OF
CNC MACHINE
3. Spindle:
• The rotating component that holds the cutting tool.
• The spindle speed and direction are controlled by the
CNC controller.
• It determines the cutting speed and affects the surface
finish of the machined part.
4. Tool Changer:
• An automatic or manual system that changes cutting
tools as needed during machining.
• Reduces downtime by eliminating the need for manual
tool changes.
• Improves the machine's flexibility for handling different
machining operations.
5. Tool Magazine:
• Storage for various cutting tools.
• Holds multiple tools, allowing for a range of machining
operations without manual intervention.

13. COMPONENTS OF
CNC MACHINE
6. Worktable:
• The surface on which the workpiece is mounted.
• It can move in different directions based on the CNC
program.
• Some CNC machines have a rotary table for multi-
axis machining.
7. Guideways and Rails:
• Mechanical components that guide the movement
of the machine's parts.
• Ensure precise and smooth motion of the tool,
worktable, or other components.
8. Control Panel:
• Allows the operator to input commands, control the
machine, and monitor its status.
• Includes buttons, switches, and a display for user
interaction.

14. OVERVIEW OF G-
CODE
 Definition:
• G-code is a programming language used to control the movements
and operations of a CNC machine.
• It defines toolpaths and coordinates for the machine to follow during
machining.
 Usage:
• Specifies the type of movement, such as rapid positioning, linear or
circular interpolation, and tool changes.
• Determines the tool’s position in space and the path it takes to reach
that position.

15. OVERVIEW OF G-
CODE
 Common G-codes:
• G00 – Rapid Positioning
• G01 – Linear Interpolation (Controlled movement)
• G02/G03 – Circular interpolation (clockwise/counter clockwise)
• G20/G21 – Inch/metric units
• G90/G91 – Absolute/Incremental positioning
• G94/G95 – Feed per minute/feed per revolution

16. OVERVIEW OF M-
CODE
 Definition:
• M-code is used to initiate miscellaneous machine functions,
such as starting or stopping the spindle, turning coolant on or
off, and tool changes.
 Usage:
• M-codes control auxiliary functions and operations beyond
tool movement.
• Activates or deactivates specific machine features or
accessories.

17. OVERVIEW OF M-
CODE
 Common M-codes:
• M00 – Program stop
• M01 – Optional program stop
• M03 – Start the spindle clockwise (turn on)
• M05 – Stop the spindle (turn off)
• M06 – Tool change

18. TYPES OF CNC MACHINES
CNC Milling Machine
CNC Lathe Machine
CNC Grinding Machine
CNC VTC CNC HMC
VMC

19. TYPES OF CNC
MACHINES
 CNC Milling Machine:
• Used for cutting and shaping
solid materials.
• The cutting tool rotates to
remove material from the
workpiece.
• Suitable for producing complex
shapes and precision parts.

20. TYPES OF CNC
MACHINES
 CNC Lathe Machine:
• Rotates the workpiece on its axis
while a cutting tool moves linearly.
• Used for turning cylindrical parts
such as shafts, bushings, and bolts.
• Can be equipped with live tooling
for additional operations.

21. TYPES OF CNC
MACHINES
 CNC Grinding Machine:
• Specialized for precision grinding
operations.
• Used for surface grinding,
cylindrical grinding, and tool and
cutter grinding.
• Common in the production of
precision component

22. TYPES OF CNC
MACHINES
 CNC Vertical Turning Center (VTC):
•Vertical turning centers have a vertical
spindle orientation.
•Workpiece is mounted on a horizontal
table that rotates vertically.
•Mainly used for Turning Operations,
where the cutting tool removes
material as the workpiece rotates.

23. TYPES OF CNC
MACHINES
 CNC Vertical Machining Center (VMC):
•Vertical machining centers have a vertical
spindle orientation.
•Workpiece is mounted on a horizontal
table that rotates vertically and horizontally.
•Capable of milling, drilling, reaming,
tapping, boring etc. using various
cutting tools.

24. TYPES OF CNC
MACHINES
 CNC Horizontal Machining
Center (HMC):
• Horizontal machining centers
have a horizontal spindle
orientation.
• Workpiece is mounted on a
vertical table that moves
horizontally.
• Capable of milling, drilling,
reaming, tapping, boring etc.
using various cutting tools.

25. ADVANTAGES OF
CNC MACHINES
1. High Production Speed
2. Reduced Human Error
3. Reduced waste
4. High accuracy in manufacturing
5. Complex Designs

26. DISADVANTAGES
OF CNC MACHINES
1. High initial cost
2. Maintenance cost is also high.
3. Required skilled part programmer
4. Programming Complexity

27. APPLICATIONS OF
CNC MACHINES
1. Used in manufacturing of Aeroplane and its components.
2. Used in Automobile engine.
3. Used in Complex designs.
4. Used in Electronic industry.

28. THANK
YOU