Facility Layout
Chapter 5
MATERIAL HANDLING
22/01/12
Tran Van Ly
Industrial Engineering and Management
International University
Email: tvly@hcmiu.edu.vn
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Lecture outline
1.
2.
3.
4.
5.
6.
7.
Introduction
Material handling principles
Designing material handling systems
Unit load design
Material handling equipment
Estimating material handling costs
Safety considerations
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I. Introduction
• 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
• 3-5% of all material handled becomes damaged
– “Totally eliminate”
– However, handling less is not the answer.
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Definitions:
• Material handling (MH) is the art and science of moving, storing,
protecting, and controlling mat of goods and materials.
– Moving: Required to create time and place utility. The value of
having the material at the right time and the right place.
– Storing: Provides a buffer between operations, facilitates the
efficient use of people and machines.
– Protecting: Includes the packaging, packing against damage and
theft.
– Controlling: Physical: Orientation, sequence and space between
material.
Status: Real-time awareness of the location, amount,
destination, origin, ownership, and schedule of material.
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Definitions:
• MH means providing the right amount of the right material, in
the right condition, at the right place, in the right position, in
the right sequence, and for the right cost, by the right
methods.
- Right amount: how much inventory is needed?
- Right material
- Right condition: state in which customer desires the material
- Right sequence
- Right place: address both transportation and storage
- Right time: on-time delivery
- Right cost: not necessary the lowest cost
- Right method.
II. MH Principles
1. Planning
9. Environmental
10. Life Cycle Cost
2. Standardization
8. Automation
MH
3. Work principle
7. System
6. Space Utilization
4. Ergonomic
5. Unit load
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Conditions for improvement
No pre-kitting of
work
System not capable
of change or
expansion
Idle production
equipment due to
material shortage
Material piled
directly on floor
Automatic data
collection system
not used
MH
Backtracking of
material
In-plant containers
not standardized
Misdirected material
Operators travel
excessively for
materials and
supplies
Excessive
demurrage
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III. Designing material handling systems (MHS)
Six-step engineering design process:
1. Define the objectives and scope for the material handling system.
2. Analyze the requirements for moving, storing, protecting, and
controlling material.
3- Generate alternative designs for meeting material handling
system requirements.
4. Evaluate alternative material handling system designs.
5. Select the preferred design for moving, storing, protecting, and
controlling material.
6. Implement the preferred design, including the selection of
suppliers, training of personnel, installation, debug and startup of
equipment, and periodic audits of system performance.
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1. Developing Alternative MHS Designs
NADLER’s IDEALS approach:
1.
2.
3.
4.
Aim for the theoretical ideal system.
Conceptualize the ultimate ideal system.
Design the technologically workable ideal system.
Install the recommended system.
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2. The MHS equation & questions
The MHS equation:
Materials + Moves +
Methods =
Recommended systems
The What Question
1. What are the types of material to be moved?
2. What are their characteristics?
3. What are the amounts moved and stored?
The Where Question
• Where is the material coming from? Where should it
come from?
• Where is the material delivered? Where should it be
delivered?
• Where is the material stored? Where should it be
stored?
• Where can material handling tasks be eliminated,
combined or simplified?
• Where can you apply mechanization or automation?
The When Question
1. When is material needed? When should it be moved?
2. When is it time to mechanize or automate?
3. When should we conduct a material handling
performance audit?
The How Question
1. How is the material moved or stored? How should
material be moved or stored? What are the alternative
ways of moving or storing the material?
2. How much inventory should be maintained?
3- How is the material tracked? How should the material
be tracked?
4. How should the problem be analyzed?
The Who Question
1. Who should be handling material? What are the
required skills to perform the material handling tasks?
2. Who should be trained to service and maintain the
material handling system?
3. Who should be involved in designing the system?
The Which Question
1. Which material handling operations are necessary?
2. Which type of material handling equipment, if any,
should be considered?
3. Which material handling system is cost effective?
4. Which alternative is preferred?
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3. MH planning chart
Fig 05_02: MH planning chart for an air flow regulator.
Key: Operation – O, Transportation – T, Storage – S, Inspection – I.
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IV. UNIT LOAD design
“Picked up and moved between two
locations as a single mass”
Example:
1. a single item picked up and moved
manually between two locations
2. Two tote pans with identical
components picked up moved by a dolly
from one machine to another
3. One pallet load of nonuniform-size
cartons with different products picked
up and moved by a lift truck from the
packaging area to the shipping dock
4. One full load of products delivered by a
trucktrailer from a warehouse to a
customer store If the trailer is half full, it
is still one unit load.
Larger unit load:
+ fewer moves
- bigger and heavier equipment
- wider aisles
- higher floor load capacities
- increased work-in-process inventory
Smaller unit load:
+ reduced work-in-process inventory
+ simple material handling methods
(i.e., push carts)
+ reduced completion time (How??)
- more moves
- increased material handling time
“Achieving single unit production
requires the material handling time to
be shorter than the unit processing
time.”
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Components of production lead time.
Setup
time
Lead Time is made up of the following elements:
o
o
o
o
o
o
o
o
o
o
Queue.
Transportation.
Inspection
Unnecessary Motion
Wait Time.
Rework/Scrap.
Overproduction.
Excess inventory and WIP.
Run Time.
Inefficient plant layout
All these lead time factors influence Set-Up Times and provide
focus on what to reduce or eliminate as part of the Set-Up
Reduction Program---- WASTE ELIMINATION.
 Increased flexibility – much easier to slot in that
urgent order or to service multiple customers or
part numbers
 Reduced batch sizes – Shorter setup times allow
running smaller batches more often  one-piece
flow
 Reduced stock and WIP (Work in Progress)
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Fig 05_03
illustrates the effects of the unit load
size on job completion times
- Processing time = 1 time unit per piece
- Material handling time = 2 time units
per move
Completion time
Earliest available
1
2
4
8
16
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4

Fig 05_04
shows several
stages in the
material flow
process where
dimensional
relationships
play a major
role.
4

Type equation here.
=32*3=96”
=48*2=96”
=8*12+6=106”
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Stackability
Nestability
Fig 05_05
shows why
these two
features
play key
roles in
moving
and storing
containers
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Efficiency of returnable containers
•
Given the following dimensions of a plastic reusable containers:
– Inside dimensions: 18” x 11” x 11”
– Outside dimensions: 20” x 12” x 12”
– Each nested container: 20” x 12” x 2”
– The storage opening : 24” x 16” x 14”
A trailer with inside dimensions of 240” x 120” x 120” is used to transport these containers.
Assume no clearance is needed.
Determine the following:
1. Container space utilization: container efficiency: (18” x 11” x 11”)/(20” x 12” x 12”) = 0.76
2. Storage space efficiency : (18” x 11” x 11”)/(24” x 16” x 14”) = 0.45
3. Container nesting ratio: 12”/2” = 6: the ratio is 6:1
4. Trailer space utilization if all containers are stacked vertically in only one orientation
i.
In the trailer length: 240”/20” = 12 containers
ii. In the trailer width: 120”/ 12’ = 10 containers
iii. In the stack vertically: 120”/ 12’ = 10 containers
iv. The total numbers of containers: 12x10x10 = 1200.
v. The trailer space utilization: (18” x 11” x 11”)(1200)/(240” x 120” x 120”) = 0.76
5. Trailer return ratio
i.
Number empty containers of one stack 1 + (120” -12”)/2” = 55
ii. Total no. of empty containers per trailer : 55 x (240”/20”) x (120”/12”) = 6600
iii. The trailer return ratio: 6600/1200 = 5.5
Significant cost reduction may be achieved with higher trailer return ratios.
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Fig 05_06
Shows a
container/pallet
system with
progressive
dimensions.
Type equation here.
2^(-n)
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Unit load interactions with warehouse components
Figure 5.10
Schematic layout of a
manufacturing
subsystem of
packaging,
palletization,
storage, and shipping.
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The pallet loading pattern for each carton-pallet pair must be prescribed
as shown in two above figures.
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V. Material handling equipment
Categories of Material Handling Equipment
1. Containers and Unitizing Equipment
• Containers
• Unitizers
2. Material Transport Equipment
• Conveyors
• Industrial Vehicles
• Monorails, Hoists, and Cranes
3. Storage and Retrieval Equipment
• Unit Load Storage and Retrieval
• Unit Load Storage Equipment
• Unit Load Retrieval Equipment
• Small Load Storage and Retrieval
4. Automatic Data Collection and Communication Equipment
• Automatic Identification and Recognition
• Automatic Paperless Communication
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Containers: Tote pans
Containers: Pallets
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Unitizers: Palletizer
Unitizers: Stretchwrapper
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Conveyors
Automatic
identification and
recognition
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Industrial Vehicles
Storage and Retrieval
Monorails, Hoists and Cranes
Stock to operator: Carousels
VI. Estimating material handling costs
• The development of MH design alternatives covers
not just the specification of the “right method of
handling”.
• The recommended alternative is at the “right cost”.
• Estimation of the cost of MH alternatives is not a
trivial task.
• That is a “roughcut” method through the use of
standard data and rules of thumb.
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VII. Safety considerations
• The key to a safe facility is concentrating on the
interface between the workforce and the
equipment.
• The following table shows recommended aisle
widths for facility design.
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VII. Safety considerations
•
•
•
•
•
•
Falling objects
Fire fighting equipment
Marking (Walk, non-stop etc.)
Loading capacity
Turning diameter
Strapping of cargo
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VII. Safety considerations
•
•
•
•
Collapsing of racks!
Collision
Explosion Proof
Handling & storing NC
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HW4
1.
2.
3.
What do you understand by identification and control
equipment and list the major types of identification and
control equipment
What is Unit load? Give the advantages and
disadvantage of large unit loads and small unit loads.
Explain following material handling principles
a.
Standardization principle
b.
Automation principle
c.
Ergonomic principle
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