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Chapter :
✓
1
The Role of Operations Management
2
Analyzing Operations
3
Inventory Management
4
Total Quality Management
5
Operations Strategy
6
Supply Chain Management
7
Business Process Reengineering
8
Planning & Control
9
New Product/process development
10
Project Management
11
Issues For International Operations
12
Time Based Competition
13
Cost Elements
Production & Operations Management
Lecture Outlines

Start Questioning operations productivity

Eliminating unuseful operations

CombinIing operations

Improving Operations Productivity

(Re) Design of new processes

Discussing the 9 primary approches to Operations Analysis
1.
2.
3.
4.
5.
6.
7.
8.
9.
Operation Purpose
Part Design
Tolerances and Specs
Material
Manufacturing Sequence and Process
Setup and Tools
Material Handling
Plant Layout
Work Design
Operation Purpose
• Ask:
– “Does this operation serve a useful purpose?”
– “Is this operation really needed?”
• Try to:
– Eliminate operations
– Combine operations
As many as 25% of operations in American Industry can be
eliminated.
Example 1 : Operation Elimination
• Many stores have dropped the requirement that customers
sign their credit slip for small totals: less than $15 - $50.
• This makes the payment transaction very fast!
– E.g. in coffee shop study,
Average payment transaction time: 27 sec
Example 2 : Operation Elimination
Outsource operations
• Ask: “Can a supplier an operation more economically than
we can in-house?”
• Operation: pack ball bearings in grease
• Modification: purchase sealed bearings from supplier.
Example 3 : Operation Elimination
Eliminate re-work
Coffee shop worker:
• Worker pours milk into stainless steel beaker,
• Steams milk, pours into cup.
• Runs out of milk – must pour and steam more while customer
waits impatiently.
Solution:
• Add measuring lines to inside of beaker so worker does not
have to estimate how much milk to pour.
Part Design
Design for manufacturing and life-Cycle
• Reduce parts – simplify designs
• Reduce processing operations
• Utilize better material
• Loosen tolerances where possible
• Design for manufacturing: choose an easy to manufacture
shape over a difficult one.
Minimum cost design
• It helps designers if they understand processes such as:
casting, molding, bending, etc.
• Example: instead of:
– Four bends in sheet metal to make part,
– Make lower cost extrusion with 4 bends already in it.
• This type of thinking is called
“Design for Manufacturing”
Tolerances and specifications
• Designers tend to incorporate tolerances that are more
rigid than necessary
• Why? To be extra sure that product will function in all
situations.
• It is perceived to reduce risk, but it can add much
unnecessary cost,
• Need to consider risk/cost trade-off.
• Taguchi (86) methods develop quality products and
reduce cost.
Material
• Incorporate better, more economical material in designs:
–
–
–
–
–
–
Less expensive
Easier to process
Use materials more economically
Use supplies and tools more economically,
Standardize materials
Find best vendor: price, stock. Can achieve 10% to 15%
reductions by shopping around, sometimes every year.
Example: New material
• Replace stamped gear with plastic gear in assembly.
 saved $0.13 per unit, $10,000 per year.
Keiretsu: (Japanese term) interlocking relationship between
manufacturers and suppliers.
Manufacturing Sequence
and Tools
• Re-sequence operations
• Group operations that can share common fixturing
• Mechanize manual operations where economically
feasible (see section on setup)
• Use more efficient facilities (see section on layout)
Example, substitute Super automatic cappuccino
machines for old style.
• Manufacture near-net shape.
• Use Robots (where economically feasible – usually for
long product runs, small product variability)
Example: re-sequencing
Original sequence:
• Paint part 1
• Paint part 2
• Paint part 3
• Paint part 4
• Rivet parts together
New sequence:
• Rivet parts together
• Paint one assembly
Setup, Tools and Fixtures
• Carefully consider economic trade-offs:
– Will the setup, fixtures, or tools be used enough to justify
their expense?
• Prevalent mistake of tool makers and planners:
– Too much specialized tooling and fixturing
Example: Tooling
• Good choice:
– Tooling that saves 10% on each job and is used frequently.
• Poor choice:
– Tooling that saves 90% on each job but is used only twice a year.
(Will not recover expense of creating and storing tooling).
Material Handling
The best way to handle material is NOT to handle it.
• Moving, storing, positioning, tracking.
• Insuring that materials get where they need to be when
they are needed.
• Material Handling Institute survey says 35 to 85% of the
cost of getting a product to market is associated with
material handling.
Better Material Handling
• Reduces cost, time
• Increases safety, health and well being of workers:
– 40% of plant accidents happen during material handling
– 25% are caused by lifting and shifting material
Approach to reducing material
handling time
• Reduce time spent picking up material
• Use mechanized of automated equipment (where
economically feasible)
• Make better use of existing handling facilities
• Handle material with greater care
• Consider bar coding
Plant Layout
• Poor layout can result in major costs through increased
travel time, increased material handling, etc.
• Two types of layouts for plants:
•
•
Product layout: machines placed in the order used in the
manufacturing process.
Advantage: reduces travel time
Process layout: machines grouped by type: e.g. all lathes together,
all drill presses together, etc.
Advantage: makes training easier.
• Later we will discuss Muther’s Systematic Layout Process
(SLP).
Work Design
• Eliminate operations,
• Re-sequence, re-design operations
Many of our remaining chapters focus on
many different types of work design!
Muther’s (1973)
Systematic Layout Process (SLP)
1.
2.
3.
4.
5.
6.
Chart out relationships between areas based on magnitude of
material handling,
Establish space requirements,
Make activity relationship diagrams
Space relationship layout
Evaluate alternative layouts
Select best layout, plan installation.
Goal: identify how to rearrange space to make it more effective for a task.
“Goodness” score for each option i is Σ (importance weight j * performance score i j)
Decision Matrices
Performance Parameters
Renovation
Cost
Material
handling
cost
importance
(1 least,
10 most)
8
10
5
7
Option 1
3
3
4
2
88
Option 2
4
3
4
1
89
Option 3
2
4
3
3
92
Use of Space
Aesthetics
Goodness
Score
A PM is whatever is important to the decision maker in the situation,
Select the best layout for your
purposes
1.
88
Choose the Layout with the
highest “score” from your
decision matrices
2.
89
3.
92
Best!
THANK YOU!
Ahmed BELAFQUIH