Unit iv Shop floor control and FMS

ME 2402 – COMPUTER INTEGRATED
MANUFACTURING (CIM)
YEAR/SEMESTER : IV/VII
UNIT IV SHOP FLOOR CONTROL AND
INTRODUCTION TO FMS
Prepared By
MANIMARAN.M
ASSISTANT PROFESSOR
K.RAMAKRISHNAN COLLEGE OF ENGINEERING
TRICHY
1/25/2016 1M.MANIMARAN KRCE TRICHY

UNIT IV SHOP FLOOR CONTROL AND INTRODUCTION TO
FMS
Shop floor control – phases – factory data collection
system – automatic identification methods – Bar code
technology – automated data collection system. FMS –
components of FMS – types – FMS workstation – material
handling and storage system –FMS layout- computer
control systems – applications and benefits.
1/25/2016 M.MANIMARAN KRCE TRICHY 2

SHOP FLOOR CONTROL
A shop floor control system is defined as a system for utilizing
data from as well as data processing files to maintain and
communicate information on shop orders and work centers. It
also known as Production Activity Control (PAC).

Function of SFC
Scheduling
Dispatching
Follow-up
Providing output data
Providing efficiency

Phases of SFC
1. Order release
phase provides the documentation needed to process a production
order through the factory.
The collection of document is called as shop packet.
Route sheet
Material requisitions
Job cards
Move tickets
Part list

Phases of SFC
2. Order scheduling
order scheduling executes the dispatching function in production planning and control.
Two elements of order scheduling
• Machine loading
• Job sequencing
Priority sequencing rules (or)Dispatching rules
SOT (shortest operating time)
Earliest due date
STR (slack time remaining) = time remaining before due date-remaining process
time
STR/OP = STR/No.of. Remaining operations
Critical ratio (CR) = Due date – Current date/No.of remaining working days
Queue ratio (QR) = slack time remaining in the schedule /planned remaining
queue time
First – come, first served
Last – come, last served1/25/2016 M.MANIMARAN KRCE TRICHY 6

Phases of SFC
3. Order progress
The order progress phase monitors the status of the various orders
in the plant, work-in-progress and other characteristics that
indicate the progress and performance of production.
Three forms of order progress report as follow as
Work order status report
Progress report
Exception report

Factory data collection system
Several data collection techniques used to collect data from the shop
floor. These techniques require the employees to gather the data and
later the data are gathered on a fully automated systems that
requires no human participation.
Types of data collected by FDC
– List number of parts that are scraped
– List number of parts requiring rework
– Equipment downtime
– Time clock by employees for punch in and out.
– Time taken at each work Centre
– Labor time in each work order
Factory data collection system

Types of data collection system
1. On-line data collection system
The data are entered directly into the plant computer system
and are immediately available to the order progress
2. Off-line data collection system
the data are collected temporarily in a storage device to be
entered and processed by plant computer in a batch mode

Automatic identification method
It refers to various technologies used in automatic (or) semi-
automatic acquisition of product data entry into a computer
system.
Basic components
• Encoded data
• Machine reader (or) scanner
• Decoder

Types of Automated Identification Technology
Bar codes
Radio frequency systems
Magnetic stripe
Optical character recognition
Machine vision

Application
1. Material handling
– Shipping and receiving and Storage
– Sortation
– Order picking
– Parts for assembly
2. Manufacturing
– Order processing
– Work-in-process
– Machine utilization and Worker attendance
3. Retails sales and inventory
4. Ware housing and distribution center operations
5. Mail and parcel handling
6. Patient identification in hospitals
7. Cheque processing in banks1/25/2016 M.MANIMARAN KRCE TRICHY 12

BAR CODE TECHNOLOGY
• It is most the most popular method of automatic identification
in factory data collection.
• Bar code technology was invented in 1949 by Norman J.
Woodland and Bernard silver of USA.

BAR CODES TECHNOLOGY

Bar codes technology
Commonly used bar codes are:
Code 39 interleaved two-of-five(ITF)
Universal product code code 93
Code 128 Codabar

Radio frequency identification

AUTOMATED DATA COLLECTION SYSTEM
Computer process monitoring involves the use of the computer
to observe the process and associated equipment and to collect
and record data from the operation.
• Data acquisition system
• Data collection system
• Multi level scanning

Flexible manufacturing system
DEFINITION
• FMS is highly automated GT Machine cell, consisting of group of
processing stations interconnected by automated material handling
system and controlled by computer system.
• or
• A flexible manufacturing system (FMS) is a form of flexible automation
in which several machine tools are linked together by a material-
handling system, and all aspects of the system are controlled by a central
computer.

TYPES OF FLEXIBILITY
There are three levels of manufacturing flexibility.
a) Basic flexibilities
1.Machine flexibility: The ease with which a machine can process various
operations
2.Material handling flexibility: A measure of the ease with which different part
types can be transported and properly positioned at the various machine tools in a
system
3.Operation flexibility: A measure of the ease with which alternative operation
sequences can be used for processing a part type

b) System flexibilities
1.Volume flexibility
2.Expansion flexibility
3.Routing flexibility
4.Process flexibility
5.Product flexibility
c) Aggregate flexibilities
1.Program Flexibility
2.Production Flexibility
3.Market Flexibility

TESTS OF FLEXIBILITY
The following are four reasonable tests of flexibility in an
automated manufacturing system :
 Part variety test. Can the system process different part
styles in a non batch mode?.
 Schedule change test. Can the system readily accept
changes in production schedule, and changes in either part
mix or production quantity.
 Error recovery test. Can the system recover quickly from
equipment breakdowns, so that the production is not
completely disrupted.
 New part test. Can new part designs be introduced into the
existing product mix with relative ease.

COMPONENTS OF FMS
FMS has the following components.
Workstation
Material Handling and Storage System
Computer Control System
Human Resources

WORKSTATION
Following are the types of workstations typically found in an FMS
1. Load/Unload Stations.
2. Machining Stations.
3. Other processing Stations. (punching, shearing, welding,
etc.)
4. Assembly Station.
5. Inspection station.
6. Other Stations and Equipment. (Inspection, Vision, etc)

MATERIAL HANDLING SYSTEM
The various automated material handling systems are used to
transport work parts and subassembly parts between the
processing stations.
Functions:
1. Random, Independent movement of work piece between
stations.
2. Handle variety of Parts
3. Temporary storage
4. Convenient access for loading and unloading
5. Compatible with computer control.

COMPUTER CONTROL SYSTEM
1. Production Control
2. Workstation Control
3. Quality Control
4. Failure diagnosis
5. Safety Monitoring
6. Work piece Monitoring
7. Performance Monitoring and Reporting

HUMAN RESOURCES
Human are needed to manage the operations of the FMS.
Functions typically performed by human includes:
1. Loading raw work parts into the system,
2. Unloading finished parts (or assemblies) from the system,
3. Changing and setting tools,
4. Equipment maintenance and repair,
5. NC part programming in a machining system, and
6. Programming and operation the computer system.

FMS LAYOUT CONFIGURATION
These are different types of layout:
1. Inline or progressive layout
2. Loop Layout
3. Ladder Layout
4. Open-field Layout
5. Robot Centered Layout

INLINE LAYOUT

Loop Layout

LADDER LAYOUT

TYPES OF MATERIAL HANDLING SYSTEM
1. Conveyor
2. Cranes and Hoists
3. Industrial Trucks
4. Monorails
5. AGV’s
6. Industrial Robots

Conveyor

Cranes

Hoists

Trucks

RGV and AGV

FMS APPLICATION
1. Machining
2. Sheet metal working
3. Plastic Injection Moulding
4. Forging
5. Welding
6. Textile Machinery manufacture
7. Semiconductor Manufacture

ADVANTAGE OF FMS
1. Increased machine utilization
2. Reduced Inventory
3. Reduced Lead times
4. Greater Flexibility in production scheduling
5. Reduced direct labor cost
6. Increased Labor productivity
7. Consistent quality

DISADVANTAGES OF FMS
1. High Capital Investment is required
2. Training and Maintaining knowledge labor is difficult
3. Cost of Fixture
4. Conditioning Monitoring is expensive
5. Sophisticated manufacturing systems
6. Limited ability to adapt to changes in product or product mix.

THANK YOU!!

Unit iv Shop floor control and FMS

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