3. WHAT IS MATERIAL HANDLING
Movement
Storage
Protection
Control (Of material throughout manufacturing)
And distribution process including consumption and
disposal.
Includes (raw material ,work in progress ,sub
assemblies ,finished assemblies)
4. MATERIAL HANDLING ACCOUNTS FOR:
25%
of all employees,
55% of all factory space,
87% of production time
15-70% of the total cost of a manufactured product
5. PRINCIPLES OF MATERIAL HANDLING
1)
Planning Principle
(needs, desirable option ,consultation, performance)
2)
3)
Standardization Principle
Work Principle
without sacrificing productivity)
4)
Ergonomic Principle
(safety, eliminate repetitive jobs )
5)
6)
7)
8)
9)
Unit Load Principle
Space Utilization Principle
System Integration Principle
Automation Principle
Environment Principle
(energy, impact, hazard)
10)
Life Cycle Cost Principle
(minimized
6. OBJECTIVES OF MATERIAL HANDLING
Reduce manufacturing cycle time
Reduce delays, and damage
Promote safety and improve working conditions
Maintain or improve product quality
Promote productivity
Material should move as short a distance as possible
Use gravity
Move more material at one time
Automate material handling
Promote increased use of facilities
Promote the use of building cube
Purchase versatile equipment
Develop a preventive maintenance program
Maximize the equipment utilization etc.
7. CONSIDERATIONS IN MATERIAL HANDLING
SYSTEM DESIGN
Material characteristics
Flow rate
Routing
Scheduling
Plant layout
10. PLANT LAYOUT
Layout Type
Characteristics
Typical MH Equipment
Fixed – position
Large product size, low
production rate
Cranes, hoists, industrial
trucks
Process
Variation in product and
processing, low and
medium production rates
Hand trucks, forklift
trucks, AGVs
Limited product variety,
high production rate
Conveyors for product
flow, trucks to deliver
components to stations.
Product
11. ROUTING AND SCHEDULING
Routing - pick-up and drop-off locations, move
distances, routing variations, conditions along the
route (surface, traffic, elevation)
Scheduling - timing of each delivery
Prompt delivery when required
Use of buffer stocks to mitigate against late deliveries
12.
13. CATEGORIES OF
MATERIAL HANDLING EQUIPMENT
1.
2.
3.
4.
Material transport equipment - to move
materials inside a factory, warehouse, or other
facility
Storage - to store materials and provide access
to those materials when required
Unitizing equipment - refers to
(1) containers to hold materials, and
(2) equipment used to load and package the
containers
Identification and tracking systems - to identify
and keep track of the materials being moved and
stored
14. UNIT LOAD PRINCIPLE (UNITIZING)
In general, the unit load should be as large as
practical for the material handling system that will
move and store it
A unit load is the mass that is to be moved or otherwise
handled at one time
Reasons for using unit loads in material handling:
Multiple items handled simultaneously
Required number of trips is reduced
Loading/unloading times are reduced
Product damage is decreased
18. WHY USE AUTOMATION IN MATERIAL
HANDLING
1.
2.
3.
4.
5.
6.
7.
8.
9.
To increase labor productivity
To reduce labor cost
To mitigate the effects of labor shortages
To reduce or remove routine manual and clerical
tasks
To improve worker safety
To improve product quality
To reduce manufacturing lead time
To accomplish what cannot be done manually
To avoid the high cost of not automating
20. 1. AUTOMATED GUIDED VEHICLE
What is AGV ?
Material handling system that uses independently
operated, Self-propelled vehicles, Guided along
defined pathways.
Increase efficiency and reduce costs by helping to
automate a manufacturing facility or warehouse.
Carry loads or tow objects behind them in trailers.
The trailers can be used to move raw materials or
finished product.
The AGV can also store objects on a bed. some
AGVs use fork lifts to lift objects for storage.
AGVs are employed in nearly every
industry, including, paper, metals, newspaper and
general manufacturing.
21. HISTORY
Developed by AM Barrett Jr in 1954
(overhead wire to guide a modified towing truck
pulley in a grocery warehouse)
1973,Volvo developed AGV to serve assembly
platforms for moving car bodies through its final
assembly plants.
Today the AGV plays an important role in the
design of new factories and warehouses.
24. DRIVER LESS TRAINS
Consists of towing vehicle, which is the AGV that pulls.
One or more trailers forming a train.
Heavy payloads.
Large distances like in a warehouse.
With or without intermediate pick-up and drop-off points along its
path.
26. PALLET TRUCKS
shift palletized loads along programmed path.
the vehicle is backed into the loaded pallet by act
of human operator that steers the truck and uses
the forks to lift the load vaguely.
The human operator will then drive the pallet
truck to its route, program its destination and
the vehicle will then automatically travel to the
preprogrammed destination for unloading.
Capacity -several thousand kilograms and some
are capable of handling two pallets.
32. 1. IMBEDDED GUIDE
•Faster and safer
•More accurate
•Less costly
WIRES •Simpler and less programming
required
33. CHOOSING APPROPRIATE PATH IN WIRE
GUIDED SYSTEM
Frequency select method
Use different frequency
generators for different
paths.
Guide wires leading into
the two separate paths at
the switch have different
frequency
At switch vehicle reads
identification code of
destination frequency
and follows it.
Path select method
Same frequency
throughout
At switch power is
turned off in all other
branches except the
one that the vehicle is
to travel on.
35. 2. PAINT STRIPS (OPTICAL NAVIGATION SYSTEM)
Chemical or tape strip is fixed or
painted to the floor which contain
fluorescent particles that reflect
UV light source from vehicle
Vehicle has an onboard sensor
which allows it to detect the path.
Not typically used in plants or
warehouses because floor line
needs to be cleaned or reapplied
as it deteriorates with time.
Useful in environment where guide
wires in the floor surface is not
practical.
36. Advantage
can be easily removed
and relocated if the
course needs to change.
It also does not involve
the expense of cutting
the factory or warehouse
floor for the entire travel
route.
"passive" system since it
does not require the
guide medium to be
energized as wire does.
less expensive
Drawback
Repaint
Cannot be used in dirty
conditions
37. 3. MAGNETIC TAPE/GRID NAVIGATION SYSTEMS
Magnetic tape is
adhered on the surface
of the floor
A sensor on underside
of vehicle detects the
magnetic tape
Can operate off tape
path
Similar to wire
guidance
38. 4. SELF GUIDED
(LASER TRIANGULATION NAVIGATION SYSTEM)
Most
popular method of AGV navigation.
Operate without continuously defined pathways.
Use combination of dead reckoning (capability
of a vehicle to follow a given route in the absence
of a defined pathway) and beacons located
throughout the plant, which can be identified by
on board sensors.
Continuously verify position by comparing the
calculated position with one or more known
position
39. HOW ARE THE VEHICLES POWERED?
TYPES OF BATTERIES, INDUCTIVE POWER AND FUEL
CELLS
1.
2.
3.
Most common batteries
Flooded lead acid
Sealed batteries
NiCad
Lithium ion
Inductive power – vehicle receives power from plate(s)
embedded in the floor. Used in some applications that
require less flexibility
Fuel cells – performing well in limited scale use in
AGVs.
The best choice of battery is based on your application.
Talk to your AGV supplier to determine which battery is
best for your application.
40. VEHICLE MANAGEMENT
Two aspects of vehicle management:
Traffic control - to minimize interference between
vehicles and prevent collisions
1.
2.
Forward (on-board vehicle) sensing
Zone control
Vehicle dispatching
1.
2.
3.
On-board control panel
Remote call stations
Central computer control
41. 1. ON BOARD SENSING
One or more sensors on vehicle
Which detect presence of other vehicles , obstacle
, or humans near by.
More effective in straight path ,less effective at
turns, convergence points.
42. 2. ZONE CONTROL
Zone control to implement blocking system. Zones A, B, and D are
blocked. Zone C is free. Vehicle 2 is blocked from entering Zone A by
vehicle 1. Vehicle 3 is free to enter Zone C.
43. VEHICLE DISPATCHING
1.
On board control panel
Manual vehicle control and programming
Lowest level of sophistication
Flexibility
2.
Remote call station
Press button at load unload stations
Programmed destination with on board panel
3.
Central computer control
Automatic dispatching
Central computer issues commands
Current location information of each AGV
Radio frequency commonly used for communication
44. VEHICLE SAFETY FEATURES
Travelling speed(< human normal walking speed)
Automatic stopping of vehicle if it strays more than a
short distance(50-150mm) –ACQUISITION DISTANCE
Obstacle detection
Emergency bumper
Warning lights ,bells , alarms etc
46. APPLICATIONS
Material transport
Storage application: Integration with AS/RS
Assembly line application
Flexible manufacturing system
Office mail delivery
Hospital material transport: meal tray, medical
supplies
48. 2. INDUSTRIAL ROBOT DEFINED
A general-purpose, programmable machine possessing
certain human like characteristics
Hazardous work environments
Repetitive work cycle
Consistency and accuracy
Difficult handling task for humans
Multi shift operations
Reprogrammable, flexible
Interfaced to other computer systems
49. INDUSTRIAL ROBOT APPLICATIONS
1.
Material handling applications
2.
Processing operations
3.
Material transfer – pick-and-place, palletizing
Machine loading and/or unloading
Welding
Spray coating
Cutting and grinding
Assembly and inspection
50. MATERIAL HANDLING APPLICATIONS
This category includes the following:
Part Placement
Palletizing and/or depalletizing
Machine loading and/or unloading
Stacking and insertion operations
The robot must have following features to facilitate material
handling:
The manipulator must be able to lift the parts safely.
The robot must have the reach needed.
The robot’s controller must have a large enough memory to store
all the programmed points so that the robot can move from one
location to another.
The robot must have the speed necessary for meeting the
transfer cycle of the operation.
51. 1. PART PLACEMENT
o
o
o
o
The basic operation in this category is the relatively simple
pick-and-place operation.
This application needs a low-technology robot of the
cylindrical coordinate type.
Only two, three, or four joints are required for most of the
applications.
Pneumatically powered robots are often utilized
52. 2. PALLETIZING AND/OR DEPALLETIZING
The applications require robot to stack parts one on
top of the other, that is to palletize them, or to unstack
parts by removing from the top one by one, that is
depalletize them.
o Example: process of taking parts from the assembly
line and stacking them on a pallet or vice versa.
o
53. 3. MACHINE LOADING AND/OR UNLOADING:
Robot transfers parts into and/or from a production machine.
There are three possible cases:
1.
2.
3.
Machine loading in which the robot loads parts into a production
machine, but the parts are unloaded by some other means.
Example: a press working operation, where the robot feeds sheet
blanks into the press, but the finished parts drop out of the press by
gravity.
Machine loading in which the raw materials are fed into the
machine without robot assistance. The robot unloads the part from
the machine assisted by vision or no vision.
Example: bin picking, die casting, and plastic molding
Machine loading and unloading that involves both loading and
unloading of the work parts by the robot. The robot loads a raw work
part into the process ad unloads a finished part.
Example: Machine operation
54. 4. STACKING AND INSERTION OPERATION
In the stacking process the robot places flat parts on
top of each other, where the vertical location of the
drop-off position is continuously changing with cycle
time.
In the insertion process robot inserts parts into the
compartments of a divided carton.
57. 3. RAIL-GUIDED VEHICLES
Self-propelled vehicles that ride on a fixed-rail
system
Vehicles operate independently and are driven by
electric motors that pick up power from an
electrified rail
Fixed rail system
Overhead monorail - suspended overhead from the
ceiling
On-floor - parallel fixed rails, tracks generally protrude
up from the floor
Routing variations are possible:
switches, turntables, and other special track
sections
60. 4. CONVEYOR SYSTEMS
Large family of material transport equipment
designed to move materials over fixed paths,
usually in large quantities or volumes
1. Non - powered
2.
Materials moved by human workers or by gravity
Powered
Power mechanism for transporting materials is
contained in the fixed path, using chains, belts, rollers
or other mechanical devices
62. 1. ROLLER CONVEYOR
Pathway consists of a
series of rollers that are
perpendicular to direction
of travel
Loads must possess a
flat bottom to span
several rollers
Powered rollers rotate to
drive the loads forward
Un-powered roller
conveyors also available
63. 2. SKATE-WHEEL CONVEYOR
Similar in operation to
roller conveyor but use
skate wheels instead of
rollers
Lighter weight and
unpowered
Sometimes built as
portable units that can
be used for loading and
unloading truck trailers
in shipping and
receiving
64. 3. BELT CONVEYOR
Continuous loop with
forward path to move
loads
Belt is made of
reinforced elastomer
Support slider or rollers
used to support
forward loop
Two common forms:
Flat belt (shown)
V-shaped for bulk
materials
65. 4. IN-FLOOR TOW-LINE CONVEYOR
Four-wheel carts
powered by moving
chains or cables in
trenches in the floor
Carts use steel pins (or
grippers) to project
below floor level and
engage the chain (or
pulley) for towing
This allows the carts to
be disengaged from
towline for loading and
unloading
66. POWERED CONVEYOR
OPERATIONS AND FEATURES
Types of motions
1.
2.
Continuous - conveyor moves at constant velocity
Asynchronous - conveyor moves with stop-and-go
motion
They stop at stations, move between stations
Another classification of conveyors:
1.
2.
3.
Single direction
Continuous loop
Recirculating
69. 5. CRANES AND HOISTS
Handling devices for lifting, lowering and transporting
materials, often as heavy loads
Cranes
Hoists
Used for horizontal movement of materials
Used for vertical lifting of materials
Cranes usually include hoists so that the craneand-hoist combination provides
Horizontal transport
Vertical lifting and lowering
73. ANALYSIS OF
MATERIAL TRANSPORT SYSTEMS
1.
2.
3.
Charting techniques in material handling
Vehicle based system
Conveyor analysis
74. ANALYSIS OF
MATERIAL TRANSPORT SYSTEMS
Analysis of vehicle-based systems
From-to charts and network diagrams
Types of systems: industrial trucks, AGVS, rail-guided
vehicles, and asynchronous conveyor operations
75. CHARTING TECHNIQUES IN MATERIAL HANDLING
(FROM –TO CHART)
TO
FRO
M
1
2
3
4
5
1
0
9/50
5/120
6/205
0
2
0
0
0
0
9/80
3
0
0
0
2/85
3/170
4
0
0
0
0
8/85
5
0
0
0
0
0
FROM –TO
CHART
showing flow
rates, (loads per
hr/travel
distance)
Flow diagram showing
material deliveries
between load/unload
stations
76. ANALYSIS VEHICLE BASED SYSTEM
Tc = delivery cycle time (min/del)
TL = time to load (min)—0.75 min
Tu = time to unload (min)---0,5 min
Ld = distance b/w load to unload (110m)
Le = distance b/w unload to load
(80 m)
v = vehicle velocity (50 m/min)
Guide path
UN
LOAD
AGV
20
Tc = TL +[Ld/v ]+ [Le/v] + Tu
55
40
Tc= 0.75 + [110/50]+[80/50]+ 0.5
Tc= 5.05 min
Tc ideal value because it ignores
Traffic congestion
Reliability problems etc
20
LOAD
Direction of
AGV
77. 1. RATE OF DELIVERIES PER VEHICLE
1)
2)
3)
Possible time loss include
Availability ( A) -proportion of total shift time that te vehicle is
operational and not broken down or being repaired)
Traffic congestion ( Tf)- blocking, waiting in queue etc
Many vehicles Tf decreases ,value ranges from 0.85 to 1
Efficiency (E)-of manual drivers if any(worker efficiency)
if not apply is taken as unity (1)
AT = available time (min/hr per vehicle)
AT = 60× A × Tf × E
Rdv = rate of deliveries per vehicle (del/hr per vehicle)
Rdv = AT
Tc
1
78. 2. NUMBER OF VEHICLES REQUIRED
Rf = specified delivery schedule or total delivery requirements
(del/ hr per vehicle)
WL = Work load(min/hr)
n = number of vehicle required
n = WL
AT
n = Rf
Rdv
2
From 1 and 2
79. LIMITATIONS OF AUTOMATED
MATERIAL HANDLING SYSTEMS
Additional investment
Lack of flexibility
Vulnerability to downtime whenever there is
breakdown
Additional maintenance staff and cost
Cost of auxiliary equipment.
Space and other requirements