2. COMPUTER INTEGRATED
MANUFACTURING
OUTCOMES:
• Can able to understand the use of computers in process
planning and use of FMS and Robotics in CIM
OBJECTIVES:
• To understand the application of computers in various aspects
of Manufacturing viz., Design, Proper planning,
Manufacturing cost, Layout & Material Handling system.
3. UNIT I
INTRODUCTION
Brief introduction to CAD and CAM – Manufacturing Planning, Manufacturing
control- Introduction to CAD/CAM – Concurrent Engineering-CIM concepts –
Computerised elements of CIM system –Types of production - Manufacturing
models and Metrics – Mathematical models of Production Performance– Simple
problems – Manufacturing Control – Simple Problems – Basic Elements of an
Automated system – Levels of Automation – Lean Production and Just-In-Time
Production.
4. CAD
CAD is the technology concerned with the use of computer systems
to assist the creation, modification, analysis and optimization of a
design.
CAD Systems are powerful tools and are used in the mechanical
design and geometric modelling of products and components.
5.
6. Reasons for implementing CAD
To increase the productivity of the designer
To improve the quality of the design
To improve communications
To create a database for engineering
7. Benefits of CAD
Increased design productivity
Shorter lead time
Flexibility in design
Improved design analysis
Fewer design errors
Greater accuracy in design calculations
Standardization of design, drafting and documentation procedures
Easier creation and correction of engineering drawing
Better visualization of drawings
Faster new products design
Benefits in manufacturing
9. Elements of CAD system
Functional areas of a CAD design Process
Geometric modelling
Design analysis and optimization
Design review and evaluation
Documentation and drafting
10.
11. Its concerned with computer compatible mathematical description of
geometry of an object
It have 3 different ways:
1.GEOMENTRIC MODELLING
12.
13. The wireframe
model is built up
using a series of
connected lines to
produce a 3D
object.
14. STEP FROM GEOMETRIC
TO PROGRAM
• Geometry algebra algorithm program
representation -Symbolic
-Numerical
-approximation
15. Wire-Frame Models
If the object is defined only by a set of nodes (vertices), and a set of
lines connecting the nodes, then the resulting object representation is
called a wire-frame model.
Very suitable for engineering applications.
Simplest 3D Model - easy to construct.
Easy to clip and manipulate.
Not suitable for building realistic models.
16. Wire Frame Models - OpenGL
Some Wireframe Models in OpenGL:
Cube: glutWireCube(Gldouble size);
Sphere: glutWireSphere(…);
Torus: glutWireTorus(…);
Teapot: glutWireTeapot(Gldouble size);
Cone: glutWireCone(…);
(…) Refer text for list of arguments.
18. The surface
model is built up
by drawing the
surfaces of an
object. Like
adding the
canvass onto the
frame of a tent.
19. The solid model is built
up by using simple
geometric forms or
extrusions - such as
cuboids, cylinders &
prisms. These can be
added or subtracted to
produce complex 3D
models.
21. Two Approaches of Solid Modelling
Constructive Solid Geometry (CSG)
Here Physical objects are modelled by combining Boolean Operations
Boundary Representations (B-rep)
Here models are created by Data structure Systems
SOLID MODELLING
22. After geometry modelling, it is subjected to Engineering analysis
(Stress, Strain, Deflections etc..) through software .
Experiments and field measurements may be necessary to find the
loads, temperature etc
2. DESIGN ANALYSIS & OPTIMIZATION
23. 3.DESIGN REVIEW & EVALUATION
Here difficulties during assembly are evaluated
Layering Procedure ,every stage of production can be checked
4. Documentation & Drafting
Here design is reproduced by automated drafting machines
Detailed drawing are developed and printed
24. CAM
Computer aided manufacturing may be defined as an effective use
of computers and computer technology in the planning management,
and control of the manufacturing function.
CAM involves the use of computers to assist in all the phases of
manufacturing a product, including process and production
planning, machining, scheduling, management and quality control.
25. APPLICATIONS OF CAM
The applications of CAM can be divided into two broad categories
Manufacturing Planning
Manufacturing Control
26. MANUFACTURING PLANNING
APPLICATIONS OF CAM
The manufacturing Planning applications of CAM are those in which computers
are used indirectly to support the production function, but there is no direct
connection between the computer and the process.
The important manufacturing planning applications of CAM includes:
Computer Aided Process Planning (CAPP)
Computer assisted NC part programming
Computerised machinability data systems
Development of work standards
Cost estimation
Production and inventory planning
Computer aided line balancing
27. Computer Aided Process Planning
(CAPP)
Process planning is an act of preparing a detailed work instructions
for the manufacture and assembly of components into a finished
production in discrete part manufacturing.
Process planning consist of :
1. The selection of manufacturing processes and operations,
production equipment, tooling and jigs & fixtures.
2. The determination of manufacturing parameters; and
3. The specification of selection criteria for the quality assurance
(QA) methods to ensure product quality.
28. Computer assisted NC part programming
Numerical control part program is the planned and documented
procedure by which the sequence of processing steps to be
performed on the NC machines
Types of part programming
Manual part programming
Computer assisted part programming
29.
30. Computerised machinability data systems
Computer programs have been written to recommend the
appropriate cutting parameters such as speed, feed and depth of cut
to use for different materials.
Advantages
It can store data from different sources
The data base can be kept up to date
Fast retrieval of selected data is possible
Rapid optimization computations are possible
Comparison of alternative cutting conditions is easy
31. Development of work standards
There are several computer packages that can be employed to
determine time standards for direct labour jobs in the factory.
They overcome tedious manual time study and motion study used to
perform the same task.
The computerized systems are based on the use of standard data of
basic work elements stored in computer either in a data file or in the
form of a mathematical formula.
32. ADVANTAGES
Reduction in time required to set the standard
Greater accuracy and uniformity in the time standards
Ease of maintaining the methods and standards file
Elimination of the biased performance rating step
Settling the time standards before the job gets into production
33. COST ESTIMATING
Cost estimating is the process of determining the probable cost of
the product before the start of its manufacture.
With the use of computers, the several steps of the cost estimating
procedure are computerized.
Computerized cost estimating is a program that can estimate the cost
of a new product, by computerizing several of the key steps required
to prepare the estimate. (such as the application of labour and
overhead rates to the sequence of planned operations)
Thus the total cost for a new product can be estimated by the
computer program by summing up the individual component costs
from the engineering bill of materials
34. Production and inventory planning
Production planning is a pre-production activity. It is the pre-
determination of manufacturing requirements such as manpower,
materials, machines and manufacturing process.
Production planning is concerned with
Deciding which products to make, how many of each, and when
they should be completed
Scheduling the production and delivery of the parts and the
products;
Planning the manpower and the equipment resources needed to
accomplish the production plan
35. Computer aided line balancing
Line balancing problem is concerned with assigning the individual
work elements to work stations so that all workers have an equal
amount of work.
Computer aided line balancing program helps to find the best
allocation of work elements among stations on an assembly line.
36. MANUFACTURING CONTROL
APPLICATIONS OF CAM
The manufacturing control applications of CAM are concerned with
developing computer systems for implementing the manufacturing
control function.
The important manufacturing planning applications of CAM includes:
Process monitoring and control
Quality control
Shop floor control
Inventory control
Just in time production systems
37. Process monitoring and control
Computer process monitoring and control is the use of a stored
program digital computer to monitor and control an industrial
process.
Computer process monitoring vs Computer process control
Computer process monitoring
It is a data collection system in which the computer is connected
directly to the workstation and associated equipment for the purpose
of observing the operation.
Computer process control
It is a process of controlling the controllable input variables with the
use of computers so as to achieved the desired performance
evaluation variables.
38.
39. Quality control
Quality control includes a variety of approaches to maintain the
highest possible quality levels in the manufactured product.
Some modern technologies in quality control are
1. Quality engineering
2. Quality function deployment
3. 100% automated inspection
4. On-line inspection
5. Coordinate measurement machines for dimensional measurement
6. Non Contact Inspection Method (Machine Vision)
40. Shop floor control
Shop floor control system is defined as a system for utilizing data
from the shop floor as well as data processing files to maintain and
communicate status information on shop orders and work centre.
Shop floor control is concerned with
1. The release of production orders to the factory
2. Monitoring and controlling the progress of the orders through the
various work centres
3. Acquiring information on the status of the orders
41. Inventory control
Inventory control is the scientific method of determining what to
order, when to order and how much to stock so that costs associated
with buying and storing are optimal without interrupting production
and sales.
The two types of inventory models
1. Fixed order quantity models (Q-models)
2. Fixed –time period models (P-models)
42. Just in time production systems
JIT is management philosophy that strives to eliminate sources of
manufacturing waste by producing the right part in the right place at
the right time.
JIT is also known as stockless production
The ideal JIT production system produces and delivers only the
required items, at the required time, and in the required quantities.
43. Sequential Engineering
Traditionally the product design is carried out by the design
department in relative isolation i.e the design department finalizes
the design and the engineering drawing without consulting the
manufacturing, quality and services departments.
All these phases are sequentially carried out
44.
45. The major weakness of sequential
engineering approach are
Insufficient production specification leading to an excessive amount
of modifications
Little attention to manufacturability issues of the product at the
design stage
Incorrect cost estimation, leading to a lack of confidence in the
estimated cost of projects
The likelihood of late changes usually leads to expensive changes to
tooling and other equipment.
46. CONCURRENT ENGINEERING
Concurrent engineering is a systematic approach to the integrated
concurrent design of products and their related processes, including
manufacturing and support.
Advantages:
Decreased product development lead time
Improved profitability
Greater competitiveness
Improved product quality
47.
48.
49. CIM
CAD+CAM = CIM
CIM is the total integration of all components involved in
converting raw materials into finished products and getting the
products to the market.
CIM is the integration of the total manufacturing enterprise through
the use of integrated systems and data communications coupled with
new managerial philosophies that improve organisational and
personnel efficiency.
50. Scope of CAD/CAM and CIM
The scope of CAD/CAM includes design, manufacturing planning
and manufacturing control.
CIM = CAD/CAM functions + Business functions
51.
52. Reasons for Implementing CIM
To meet competitive pressures
To coordinate and organize data
To eliminate paper and the costs associated with its use
To automate communication with in a factory and increase the speed
To facilitate simultaneous engineering
53. Benefits of CIM
Creation of a truly interactive system that enables manufacturing
functions to communicate easily with other relevant functional units
Faster responses to data changes for manufacturing flexibility.
Increased flexibility towards introduction of new products
Improved accuracy and quality in the manufacturing process
Improved quality of the products
Reduction of lead times which generates a competitive advantage
56. Production system
Production is the sequence of operations which transform the given
materials into desired products. This transformation from one from
to another is carried out either by one or a combination of different
manufacturing processes.
A system is a logical arrangement of components designed to
achieve particular objectives according to a plan.
57.
58. Types of production systems
Job shop production
Batch production
Mass production
Process or continuous production
59. Job shop production
Meaning: Job or unit production involves the manufacturing of a single
complete unit as per the customer’s order. This is a special order type of
production. Each job or product is different from others and no repetition
is involved.
Three types of job production
A small number of pieces produced once
A small number of pieces produced intermittently when the need arises
A small number of pieces produced periodically at known time intervals
60. Characteristics:
High variety and low volume.
General purpose machines and equipment to perform wider range of
operations.
Flow of materials is not continuous i,e., it is intermittent.
Highly skilled operators and supervisors are required.
Variable path material handling equipment's are used.
61. Merits:
It involves comparatively small investment in machinery and
equipment.
It is flexible and can be adapted easily to changes in product design.
Demerits:
Very large work in process inventory.
Difficult in planning, scheduling and coordinating the productions
of numerous components of wide variety.
Highly skilled workforce is required.
Manufacturing cycle time is more.
Suitability:
Job shop production is applicable where custom-made products are
to be produced on a small scale.
62. Batch production
Meaning: In this type, the products are made in small batches and
in large variety. Each batch contains identical items but every batch
is different from the others.
Three types of batch production are
A batch produced only once.
A batch produced repeatedly at irregular intervals, when the need
arises.
A batch produced periodically at known intervals, to satisfy
continuous demand.
63. Characteristics:
A large variety of products are manufactured in lots or batches.
Both general purpose machines and special purpose machines are
used.
Flow of material is intermittent.
Plant layout is process type.
Flexible material handling system.
64. Merits:
Short production runs.
Plat and machineries are flexible.
Medium variety and medium volume.
Demerits:
Large work in process inventory.
More number of set-ups.
Workload on various machines/sections are unbalanced.
Process and product planning is to be done for each batch.
Suitability:
Drugs, clothes, paints, parts manufactured on turret lathes, forging
machines and sheet metal presses are few examples of batch
production.
65. Mass production
Meaning: In this type of production, only one type of product or
maximum 2 or 3 types are manufactured in large quantities.
Standardisation of products, process, materials, machines and
uninterrupted flow of materials are the basic features of this system.
Mass production system offers economics of scale as the volume of
output is large.
66. Characteristics:
Low variety and high volume.
Flow of materials is continuous.
Special purpose machines are used.
Mechanised material handling systems such as conveyors are used.
The machine capacities are balanced.
Degree of mechanisation or automation is high.
67. Merits:
It offers lowest cost of production.
Shorter cycle time.
Work in process is comparatively low.
Easier production planning and control.
Relatively lower skilled persons can manage work.
Demerits:
Higher inventory of raw materials.
Less flexibility of equipment and machines.
Suitability: Electronics, electricals, automobiles, bicycles and
container industries are a few examples of mass production
industries.
68. Process or continuous production
Meaning: This type of production is used for manufacture of those
items whose demand is continuous and high. Here single raw material
can be transformed into different kind of products at different stages
of production processes. E.g., in processing of crude oil in refinery
one gets kerosene, gasoline, etc., at different stage of production.
The characteristics, merits and demerits of continuous production
system are the same as that of the mass production system.
Suitability: the industries like paper, textiles, cement, chemicals,
automobiles, etc., are a few examples of continuous production
industries.
72. Manufacturing Models and Metrics
Manufacturing metrics are used to quantitatively measure the
performance of the production facility or a manufacturing company.
Manufacturing metrics is a system of related measures that
facilitates the quantification of some particular characteristics of
production.
73. Why use manufacturing metrics?
To track performance of the production system in successive
periods.
To determine the merits, and demerits of the potential new
technologies and system.
To compare alternative methods
To make good decisions
74. Categories of manufacturing metrics:
Production performance measures
The production performance measures are metrics used to
quantify the production performance.
Manufacturing costs
Manufacturing costs include labour and materials costs, the
costs of producing its products, and the cost of operating a
given piece of equipment.
76. INTRODUCTION TO
AUTOMATION
Automation is defined as the technology that is applied to
accomplish a process or procedure without human assistance.
This technology includes
Automated assembly machines
Automated machine tools to process parts
Industrial robots
Automated material handling and storage system
Automated inspection system and quality control
Feedback control and computer process control
77. Need for automation
To increase production rate and labour productivity
To reduce labour cost
To reduce or eliminate routine manual and clerical tasks
To improve worker safety
To improve product quality
To reduce manufacturing lead time and work in process inventory
78. Basic elements of an automated
system
Power
Power to achieve the process and operate the system
Program of instructions
A program of instructions to direct the process
Control system
A control system to actuate the program of instructions and sense
feedback from the transformation process.
79.
80. Power
Power is required in an automated system
To drive the transformation itself
To operate the program of instructions and the control system
81. The role of power in an automated system can be studied
under the following two sub headings
Power for the transformation process
To drive the process itself
To load and unload the work unit
To transport between operations
Power for automation
Controller unit
Power to actuate the control signals
Data acquisition and information processing.
82. Program of instructions
The program of instructions is a series of controlled actions that are
carried out in the manufacturing or assembly process.
The program of instructions can also be called software program.
Parts or products are usually processed as part of a work cycle.
When the program steps are defined within the work cycle structure,
they are known as work cycle programs.
In numerical control (NC) system, work cycle programs are called
part programs.
83. Control system
The control system executes the program of instructions
The control system interacts with the process through actuators and
sensors.
Input parameters to the controller are converted to signals that
release power to the actuators.
The output parameters from the process are converted by the sensors
into signals. These signals are feed back to the controller and
typically compared with the input parameters.
84. Types of control system
Closed loop control system
Open loop control system
87. Levels of automation
Device level
Machine level
Cell or system level
Plant level
Enterprise level
88.
89. It is also known as Lean manufacturing
It aims for continuous elimination of all wastes in the
production process
It makes more flexible and efficient by adopting methods
that reduce waste in all forms
This concept was originated by Toyota motors ,Japan
Lean Production
90. Reduce Defect & Wastages
Reduce cycle times
Minimize Inventory levels
Improve Labour Productivity
Utilization of Equipment and Space
Flexibility
Increase the Output
Objectives of Lean Manufacturing
92. Recognition of waste
Standard processes
Continuous flow
Pull Production
Quality at the source
Continuous improvement
Principles of Lean Manufacturing
93. This is one of the management philosophy that strives to eliminate
sources of manufacturing waste by producing the right part in the
right place at the right time.
It is also known as stockless production.
JIT Production Systems
94. Zero defects
Zero setup time
Zero inventories
Zero handling
Zero breakdown
Zero leave time
Lot size of one
Objectives of JIT
95. Reduce or Eliminate setup times
Reduce manufacturing & purchasing lot size
Reduce production & delivery lead time
Preventive maintenance
Stabilize & level the production schedule
Flexible workforce
Require supplier quality assurance & implement a zero defects
quality program
Elements of JIT
96. Lower inventory cost
Lower scrap & waste costs
Improved quality & zero defect products
Improved worker involvement
Higher motivation & moral
Increased productivity
Reduced manufacturing lead time
Increased product flexibility
Benefits of JIT
