automation in manufacturing unit-1
Post on 03-Jun-2018
235 Views
Preview:
TRANSCRIPT
-
8/13/2019 Automation in Manufacturing Unit-1
1/58
AUTOMATION
I N
MANUFACTURING
-
8/13/2019 Automation in Manufacturing Unit-1
2/58
-
8/13/2019 Automation in Manufacturing Unit-1
3/58
AUTOMATION
INTRODUCTION
Is an technology by which a process or procedure is
done without human assistance.
Implemented by using an program or instruction with
control system which executes instruction.
-
8/13/2019 Automation in Manufacturing Unit-1
4/58
REASONS FOR IMPLEMENTING
AUTOMATION IN MANUFACTURING
INCREASE THE PRODUCTIVITY RATE OF LABOUR
TO DECREASE COST OF LABOUR
SHORTAGE OF LABOUR
IMPROVES WORK SAFETY
TO RESUCE MANUFACTURE LEAD TIME
TO AVOID HIGH COST OF NON AUTOMATION
TO IMPROVE WORKER SAFETY
PRODUCT QUALITY IMPROVEMENT
TO REDUCE MANUFACTURING LEAD TIME
-
8/13/2019 Automation in Manufacturing Unit-1
5/58
TYPES OF AUTOMATION
1 . FIX ED A UTO MATIO N
2. PROGRAMMABLE AUTOMATION
3 . FLEXIBLE AU TO MATIO N
-
8/13/2019 Automation in Manufacturing Unit-1
6/58
FIXED AUTOMATION
o sequence of processing or assembly operations to be
carried out are fixed by equipment configuration
o difficult to automate changes in design product
o high production rates
o time taking
o during process new products cannot be processed
-
8/13/2019 Automation in Manufacturing Unit-1
7/58
PROGRAMMABLE AUTOMATION
Production equipment is designed with the capabilityto change the sequence of operations
Controlled by an program consists of set of codedinstructions can be read and implemented by system
New program or codes can be entered to produce newproducts
High investment
Low production rates, low & medium volume
production Suitable for batch production
Example: numerical control machines(nc)
-
8/13/2019 Automation in Manufacturing Unit-1
8/58
FLEXIBLE AUTOMATION
Extension of programmable automation
Developed to minimize time loss between change
over of batch production from 1 to another
No loss of production in reprogramming & altering
Very high investment
Continuous production with variable products
Example: CNC Machines
-
8/13/2019 Automation in Manufacturing Unit-1
9/58
ADVANTAGES OF AUTOMATION
High rate of production
Requires less number of workers
Produces high quality of products
Production time period is low
General working conditions are improved
Heavy jobs can be handled easily
Adaptability to CAD/CAM
Shorter lead times
-
8/13/2019 Automation in Manufacturing Unit-1
10/58
DISADVANTAGES OF AUTOMATION
Initial cost is very high
Maintenance cost
Requires several complex control systems
Skilled workers
Break down stops whole production
Substantial preplanning is required
-
8/13/2019 Automation in Manufacturing Unit-1
11/58
STRATEGIES IN AUTOMATION
1. SPECIALIZATION OF OPERATIONS
2. COMBINED OPERATIONS
3. SIMULTANEOUS OPERATIONS
4. INTEGRATION OF OPERATIONS
5. INCREASED FLEXIBILITY
6. IMPROVING MATERIAL HANDLING
7. ONLINE INSPECTION
8. PROCESS CONTROL & OPTIMIZATION
9. PLANT CONTROL OPERATIONS
10. COMPUTER INTEGRATED MANUFACTURING (CIM)
-
8/13/2019 Automation in Manufacturing Unit-1
12/58
1. Power - to accomplish the process and operate
the automated system
2. Program of instructionsto direct the process
3. Control system
to actuate the instructions
Automation is the technology by which a process or
procedure is accomplished without human assistance.
Basic elements of an automated system :
-
8/13/2019 Automation in Manufacturing Unit-1
13/58
BASIC ELEMENTS OF AUTOMATION
PROGRAM OF
INSTRUCTIONS
CONTROL
SYSTEMPROCESS
POWER
-
8/13/2019 Automation in Manufacturing Unit-1
14/58
Electricity -
The Principal Power Source
Widely available
Can be readily converted to alternative forms,
e.g., mechanical, thermal, light, etc.
Low level power can be used for signal
transmission, data processing, and
communication
Can be stored in long-life batteries
-
8/13/2019 Automation in Manufacturing Unit-1
15/58
Power for the process
To drive the process itself
To load and unload the work unit
Transport between operations
Power for automation Controller unit
Power to actuate the control signals
Data acquisition and information processing
-
8/13/2019 Automation in Manufacturing Unit-1
16/58
Program of Instructions
Example: CNC part program
During each step, there are one or moreactivities involving changes in one or more
process parameters
Examples:
Temperature setting of a furnace
Axis position in a positioning system
Motor on or off
Set of commands that specify the sequence of
steps in the work cycle and the details of eachstep
-
8/13/2019 Automation in Manufacturing Unit-1
17/58
Control System Two Types
1. Closed-loop (feedback) control system
a system in which the output variable is
compared with an input parameter, and
any difference between the two is used todrive the output into agreement with the
input
2. Open-loop control system operateswithout the feedback loop
-
8/13/2019 Automation in Manufacturing Unit-1
18/58
Closed loop control system
open loop control system
-
8/13/2019 Automation in Manufacturing Unit-1
19/58
Temperature instructions
Example for closed loop control system
-
8/13/2019 Automation in Manufacturing Unit-1
20/58
Example for open loop control system
-
8/13/2019 Automation in Manufacturing Unit-1
21/58
Levels of Automation
1. Device level actuators, sensors, and other
hardware components to form individual control
loops for the next level
2. Machine level CNC machine tools and similar
production equipment, industrial robots,material handling equipment
3. Cell or system level manufacturing cell or
system
4. Plant level factory or production systems level
5. Enterprise level corporate information system
-
8/13/2019 Automation in Manufacturing Unit-1
22/58
Levels of Automation
-
8/13/2019 Automation in Manufacturing Unit-1
23/58
PNEUMATIC SYSTEM
-
8/13/2019 Automation in Manufacturing Unit-1
24/58
Hydraulic system
-
8/13/2019 Automation in Manufacturing Unit-1
25/58
Pneumatic system consists of
Motor driven compressor
Air receiver
Directional control valve (DCV) PNEUMATIC cylinder
-
8/13/2019 Automation in Manufacturing Unit-1
26/58
C
WEIGHT
DIRICTIONAL
CONTROL
VALVEAIR
RECEIVER
MOTOR
MOTOR
CONTROL
PNEUMATIC SYSTEM
-
8/13/2019 Automation in Manufacturing Unit-1
27/58
HYDRAULIC SYSTEM
The basic hydraulic system essentially consists of apump and a cylinder
Hydraulic piston is lifted by a hydraulic pump driven
by a electric motor
System consists of a closed-loop piping network
With a fluid transferred from a storage tank to one
side of piston
Pump converts a mechanical force to hydraulic powerand fluid is drawn from the tank
-
8/13/2019 Automation in Manufacturing Unit-1
28/58
HYDRAULIC SYSTEM
hydraulic system has significant advantageover pneumatic system in carrying loads
Range from 35 to 200 mpa
Main components are Hydraulic power supply
Electro hydraulic servo valve
Sump or tank
Hydraulic motor
-
8/13/2019 Automation in Manufacturing Unit-1
29/58
HYDRAULIC SYSTEM
PPress
ure Control
valve
FILTER
WEIGHT
PISTON
FLUID TANK
-
8/13/2019 Automation in Manufacturing Unit-1
30/58
A pressure regulation/relief valve protects the
system from high pressure
Is essential to spill excess fluid back to tank
The cylinder uses the moving oil to do work
and the cylinder movement is controlled by a
valve
The control valve directs the oil to allow
supply of oil from the pump to and from
cylinder
-
8/13/2019 Automation in Manufacturing Unit-1
31/58
AUTOMATION IN
MACHINE TOOLS
-
8/13/2019 Automation in Manufacturing Unit-1
32/58
Machine tool is defined as the machinery
used to obtain the desired properties or
geometry of the metallic or non-metallic
materials by performing various
operations
Automated machine tool is nothing but
NC(numerical control) CNC (computer
numerical control) Mostly used is CNC
-
8/13/2019 Automation in Manufacturing Unit-1
33/58
Principle functions of CNC machines
MACHINE TOOL CONTROL IMPROVED PROGRAMMING
AND WORKING FEATURES IN-PROCESS COMPENSATION
DIAGNOSTICS
-
8/13/2019 Automation in Manufacturing Unit-1
34/58
Machine tool control
This is important function of the CNC system Deals with steps and various functions of process
which are used to convert the part program
instructions into machine tool
For this conversation process is done by using the
computer interface and servo system
TYPES
1. HYBRID CNC
2. STRAIGHT CNC
-
8/13/2019 Automation in Manufacturing Unit-1
35/58
HYBRID CNC
Consists mainly 2 parts
1. Soft-wired computer
2. Hard wired logic circuitsThe hard wired circuits perform the machine tool
feed rate generation and circular interpolation
The remaining control functions and duties areassociated by the computer
-
8/13/2019 Automation in Manufacturing Unit-1
36/58
Tapereader
from
initial
program
inputinterp
olationoffsets
X Y Z
motion
Interfacing
unit
feedback
HYBRID CNC
-
8/13/2019 Automation in Manufacturing Unit-1
37/58
STRAIGHT CNC
Consists one computer to perform all NC
functions
The only hard-wired components arerequired to interface the computer with
machine tool and operator task
-
8/13/2019 Automation in Manufacturing Unit-1
38/58
STRAIGHT CNC
TAPE
READER FOR
INTIALPROGRAM
I
N
PU
T
COMPU
TATIONOFFSETS S
E
NS
O
R
S
MOTION
FEEDBACK
-
8/13/2019 Automation in Manufacturing Unit-1
39/58
IMPROVED PROGRAMMING AND WORKING
Includes1. Graphical display of tool path and verification of
tape
2. Use of specially written subroutines
3. Manual data & input method
4. Local storage of more than one part diagram
5. Interpolation techniques
6. Editing the program
-
8/13/2019 Automation in Manufacturing Unit-1
40/58
INPROCESS COMPENSATION
Recalculating and analysis of axis positioning
Offset adjustments
Accurate calculation of predicted tool life
Use of specially written sub programs
SI & METRIC units
Large storage system having more than one part
program
-
8/13/2019 Automation in Manufacturing Unit-1
41/58
DIAGNOSTICS
This function is available in modern CNC machine
It helps in maintenance and repair of the system
Its functions are
1. To minimize downtime
2. Warn about forthcoming failure of a certain
components
-
8/13/2019 Automation in Manufacturing Unit-1
42/58
MECHANICAL FEEDERS
Used in automation are
1. Centrifugal feeders
2. Drum feeders
3. Barrel feeders
4. Rotary selector ring feeders
5. Elevator feeders
6. Blade feeders
-
8/13/2019 Automation in Manufacturing Unit-1
43/58
MECHANICAL FEEDER
-
8/13/2019 Automation in Manufacturing Unit-1
44/58
CENTRIFUGAL FEEDER
-
8/13/2019 Automation in Manufacturing Unit-1
45/58
DRUM FEEDER
-
8/13/2019 Automation in Manufacturing Unit-1
46/58
ELEVATOR FEEDER
-
8/13/2019 Automation in Manufacturing Unit-1
47/58
AUTOMATIC TOOLCHANGING
-
8/13/2019 Automation in Manufacturing Unit-1
48/58
M-TAB CNC
-
8/13/2019 Automation in Manufacturing Unit-1
49/58
BED CNC
-
8/13/2019 Automation in Manufacturing Unit-1
50/58
A variety of machining process or operationmay done for finishing a particular part
So variety of tool are needed to do particularoperation
These tools are positioned on tool drum of themachine when a particular operation is done
on the part
Tool drum rotates to change the tool positionby means of ATC mechanism
This program helps to exchange the tool in thespindle and in drum
-
8/13/2019 Automation in Manufacturing Unit-1
51/58
AUTOMATIC TOOL CHANGER
-
8/13/2019 Automation in Manufacturing Unit-1
52/58
ADVANTAGES OF ATC
Reduces idle time
Usually takes 5 to 7 seconds
Identification of tool (done by codes)
Tool transfer is done by the reciprocating motion
of spindle and magazine
CLASSIFICATION OF TOOL
-
8/13/2019 Automation in Manufacturing Unit-1
53/58
CLASSIFICATION OF TOOL
CHANGE
1. According to kind of cutting tools
Single tool heads
Multi tool heads
Special tool heads
2. According to tool position
Horizontal type Vertical type
-
8/13/2019 Automation in Manufacturing Unit-1
54/58
SINGLE TOOL, MULTI TOOL
AUTOMATIC TOOL CHAGER
-
8/13/2019 Automation in Manufacturing Unit-1
55/58
AUTOMATIC TOOL CHAGER
HORIZONTAL
AUTOMATIC TOOL CHANGER
-
8/13/2019 Automation in Manufacturing Unit-1
56/58
AUTOMATIC TOOL CHANGER
VERTICAL
-
8/13/2019 Automation in Manufacturing Unit-1
57/58
According to system tool exchanger
1. Without tool change arm
2. With tool change arm
3. With tool parking position
According to position of axes of spindle
1. Parallel axes
2. Intersecting axes
-
8/13/2019 Automation in Manufacturing Unit-1
58/58
CNC MACHINE TOOLS
top related