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material handling system lecture pdf for mechanical engineering

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 handling of material in warehouse
 solving the problems involving the movement
 control and protection of materials, goods and products
 applied in both manufacturing and distributional operations
does not add
value to the
product but it
usually adds a
significant value
to the product
These early methods treated the three basic stages of handling—
a. materials collection
b. Manufacturing
c. product distribution
Modern materials-handling
systems, by contrast, emphasize
the integrated flow of goods from
the source of raw materials to final
user
This can be achieved by transporting
goods in large quantities and in
standardized units; by handling
procedures using cranes, conveyor belts,
and other machines; and by the careful
coordination of the movement of goods
with production, processing, and
distribution schedules
a.
Designing the system for continues flow of material, i.e. idle time should be
zero.
b.
Going in for standard equipment, which ensures low investment and flexibility
in case of changes in material handling requirements in the future.
c.
Incorporating gravity flow in material flow system
d.
Ensuring that the ratio of the dead weight to the payload of material handling
equipment is minimum.
Various material handling systems are in use, right from those
that are fully manual to the ones that are fully automatic.
However, the selection of a particular system depends in factors
such as:
i.
ii.
iii.
iv.
Volumes to be handled
Speed in handling
Productivity
Product characteristics
(weight, size, shape)
v. Nature of the product
(hazardous, perishable,
crushable)
The Key to Greater Productivity,
Customer Service and Profitability
1. Planning Principle: where the needs, performance objectives,
functional specifications of the methods
2. Standardization Principle: should be standardized within the
limits of achieving overall performance objectives
3. Work Principle: should be minimized without sacrificing
productivity
4. Ergonomic Principle: Human must be recognized and respected in the design of
material-handling tasks
5. Unit Load Principle: can be stored or moved as a single
6. Space Utilization Principle: All available space must be used effectively and
efficiently.
7. System Principle: Material movement and storage activities should be fully
integrated to form a coordinated, operational system that spans receiving, inspection,
storage, production, assembly, packaging, unitizing, order selection, shipping,
transportation, and the handling of returns.
8. Automation Principle: operations should be mechanized and/or automated where
feasible to improve operational efficiency
9. Environmental Principle: total energy consumption should be an evaluation
criterion
10. Life Cycle Cost Principle: A complete economic analysis should account for the
entire life cycle of all material-handling equipment and the resulting systems.
Lifting and Transport Equipment
Equipment that falls into this category is fork lift trucks, order picking trucks, overhead
cranes, tower cranes and belt, chain and overhead conveyors.
fork lift trucks
overhead conveyors
Storage Equipment
within this category are pallet racks, mobile shelf units, and plastic, wood and steel containers
Automated Handling Equipment
automated guide vehicles, storage and retrieval equipment, conveying systems and product sorting
equipment
Material Handling Equipment Selection
Properly Match:
 The Material Characteristics
 The Move Requirements
 The Equipment Capabilities/Requirements
Other factors to be considered
include:




Labor skills available
Capital available
Return on investment
Expected life of installation
STUDY ON THE APPROACHES OF THE SELECTION OF
EQUIPMENT AND DESIGN OF THE MHS
Problems to overcome : minimizes cost and maximizes reliability.
[ Sequence A ]
[ Sequence B ]
Layout Design
MHS Design
MHS Design
Layout Design
Modifications
of Layout
Review of the
MHS Design
The Solution Sequence and Preferable Relations Between MHS and Facility
Layout Design
The selection of equipment and design of the MHS
can be done using four ways:




by means of a traditional selection method,
using an analytical model,
by knowledge-based approaches,
Hybrid approaches (analytical and knowledge based approaches).
 Traditional Selection Method
1. the designer relies principally on handbooks and experience
2. approach may not be cost-effective
 Analytical Model
1. generally consider only quantifiable factors such as cost and utilization
2. often difficult to implement
 Knowledge-based Approaches
1. involves the use of expert guidelines.
2. allows extensive matching of equipment characteristics to application
requirements
PRODUCT AND PROCESS SPECIFICATIONS AND MHS
EQUIPMENT SELECTION FOR EACH PRODUCT
The choice of MHS equipment depends on the product and process requirements.
For this reason, MHS equipment can be selected according to the product and
process specifications.
Main Features of the MHS Equipment Selection
1. Product Type (bar stock, package,
pallet load, unit)
2. Product Weight
3. Product Size (Cubic Volume)
4. Product nature (Sturdy, Fragile)
5. Product Volume
1. 1.Speed Requirements
2. Accumulation Requirements (Yes or
No)
3. Distance for Transfer
4. Frequency of Movement
5. Flexibility of Process Route
6. Loading and Unloading Requirements
7. Safety Aspects
MHS Design Stages
MHS Equipment
Selection
Rationalastion of the
Selected MH
Equipments
Utilisation and Detail
Design of Material
Handling System
Finding appropriate equipment for
a handling problem involves
extensive matching of product and
process features and material
handling equipment specifications.
The Rationalization of the MHS between
departments (nodes)
Why Rationalization required ?
 Different product types are likely to require different details.
 reducing the total investment and operating cost of the MHS.
If there are material transfers between two departments and they require these two
types of equipment at the same time, the equipment types and their alternatives have
been considered and alternative choices must be established and arranged in a form.
If the requirement of MHS types is more than one and these types of equipment can
replace each other then select the dominant one.
Rail Guided Vehicle (RGV)
Automated Guided Vehicle (AGV)
Implementation Of The Approaches
The approach comprises three stages which are represented by two
different knowledge-bases and one external program.
• The knowledge-base contains all the rules and the objects which
describe a particular topic.
• function of the external program is to reorganize the data for the
MHS selection phase and has been developed using FORTRAN.
Product Database
Product
Process
Routes
MHS.EXE
Specifies MHS equipment
types for each product
MHS-DEP.DAT
Flow Chart of the Arrangement Procedure
Obtain Product and Process features for MHS
Equipment Selection
Program of Rule Set for Material Handling
Equipment Selection
The Main
Flow Chart
of the
Approach
MHS Equipments for Each Product
Organization of Selected Equipment (External
Program)
Rationalisation
Pre-Designed MHS
Utilisation and DETAIL DESIGN
MHS EQUIPMENT SELECTION FOR PRODUCTS
In a MHS equipment selection, the selection procedure can be carried out as
follows:
If the distances, the event intervals between arrival times and the components
are relatively large, an AGV system is likely to prove appropriate. For
generalization, each MHS equipment has been taken as a member of a class,
which has a certain number of features and which can be represented by slots in
a program.
example, an AGV may be represented using a class object and the details are
given [Leonardo Expert System Shell (Creative Logic, 1989)]
1: Name: AGV
2: Long Name:
3: Type:
4: Value:
5: Certainty:
6: Derived From:
7: IsA: mhs
8: Member Slots:
8: load_type: discrete
9: we_ran: high
10: load_size: mdm
11: req_speed: high
13: req_acc: very high
14: req_diss: high
15: frequ_req: often
16: path_flexi: high
17: load_un_ab: high
MHS
Equipment
Type
Load Type
Robots
Discrete
LowSolidLowMedium
Medium
Fragaile Medium
No
short
often
low
high
AGV
Discrete
Medium Medium
SolidMedium
Fragaile
No
medium
often
high
high
RGV (Rail
Guided
Vehicle )
Discrete
High
MediumLarge
Solid
High
No
long
low
low
medium
Fork Lift
Discrete
High
Large
Solid
Medium
No
long
high
high
high
Conveyors
Continuous
Solid
HighMedium
Yes
shortmedium
low
low
medium
Manual
Discrete
Solid
Low
No
short
high
high
high
Load
Capacity
Size
LowSmall Medium Medium
Low
Medium
Loading &
Speed Of Accumulation
Frequency Flexibility
Nature
Distance
Unloading
System
Required
Of Move Of Path
Ability
These suggested alternatives will clearly need development with experience of
operating the design system.
Probem : An MHS is going to be pre-designed for a plant. The plant is designed for 6
processes and 4 different parts. The parts and process routes and their specifications
are presented in Table . When the part and process routes and their MHS equipment
information have been gathered, the first stage can be carried out for MHS equipment
selection. In this selection, for example, heavy loads, Far trips, and very big in size for
Part 3, suggests the use of a Rail Guided Vehicle (RGV). Another example can be
given for Part 1. This part is of medium weight, medium in size and has a fragile
nature; these requirements can be satisfied using an AGV.
1
2
3
4
5
6
Network Analysis and
Part Root Process of the
case study
MHS Equipment for Parts
Product Number
MHS Equipment
Part 1
RGV
Part 2
Man
Part 3
Fork-Lift
Part 4
AGV
Product and Process Feature for MHS Equipment Selection
Part
Part
Part Route
Number Volume
Process
1
50
1-2-4-5-6
2
40
1-5-6-0
3
70
1-3-4-5-6
4
20
1-2-3-5-6
1
Load
Type
Load
Capacity
Size
Loading &
Speed Of Accumulatio Distanc Frequency
Nature
Unloading
System n Required
e
Of Move
Ability
medium
Fragile
Low
No
Mediu
m
High
Rare
small
Solid
Medium
No
Short
Low
No
Discrete very high
very big
Solid
High
No
Far
Low
Frequently
Discrete
medium
Fragile
Medium
Yes
Mediu
m
Medium
Frequently
Discrete medium
Discrete
high
low
2
3
4
5
6
MHS Equipment Requirements Between Departments
From
Department
To
Department
Required MHS
Equipment
Rationalized
MHS
Equipment
1
1
1
2
2
3
3
3
4
4
5
2
3
5
4
3
2
4
5
2
5
6
RGV, Fork Lift, AGV
RGV, Man, AGV,
AGV
Man
Fork Lift, AGV
AGV
Man
AGV, Man
AGV, Man
RGV, Man, AGV,
Fork Lift
RGV
RGV
AGV
Man
Fork Lift
AGV
Man
AGV
AGV
RGV
Fork Lift
Product Number
MHS Equipment
Part 1
RGV
Part 2
Man
Part 3
Fork-Lift
Part 4
AGV
 Responsive
 Flexible
 Autonomous
 Highly automatic
 Multi-functional
 Modularized
 Multi-level
 Compatible
The most possible objectives to do in future are:
••
High-speed, high-value material handling and logistics processes for
challenging environments
••
Low-cost, low-impact material handling and logistics capabilities to
maintain high service levels
••
The workforce of tomorrow and what is needed to develop it.
The field of materials handling remains still to be fully to
be fully explored.
Material handling techniques are not only industry’s
biggest opportunity — they are industry’s biggest
necessity.
Competition is beginning to force this new technology
upon industry.
Conclusions
 This study describes a decision aid which may be used by a designer who is
not very familiar with selection of material handling systems.
 The case study exemplifies the selection of MHS equipment using the
approach and a recommended rationalization procedure.
 A knowledge based approach can overcome the limitations of analytical
approaches which are generally limited with only quantifiable factors.
 Rationalizations of MHS equipment will reduce total investment and
operation costs.
 It highlights the importance of the material handling system design and
facility layout problem, requiring an integrated solution strategy.
 It'll help to work a system with full automation and there it'll create a scope
for future work on knowledge based programmed Material Handling System
Design.