Just In Time
What Is JIT
 Management
philosophy (produce
only what is needed when it is
needed)
 A highly coordinated processing
system in which goods move through
the system, and services are
performed, just as they are needed
 Represents Pull type system
History of JIT Manufacturing
 Evolved
in Japan after World War II, as a
result of their diminishing market share in
the auto industry.
 Toyota
Motor Company- Birthplace of the
JIT Philosophy Under Taiichi Ohno.
 JIT
is now on the rise in American
Industries.
Definition
 JIT
is a manufacturing philosophy
involving an integrated set of
procedures/activities designed to
achieve a high volume of production
using minimal inventories
More Introduction
 Raw
materials, parts & sub
assemblies are pulled through the
manufacturing process when they
are needed.
 Simply
put, JIT is a philosophy of
“make what is needed … when it is
needed”.
Goal of JIT





The ultimate goal of JIT is a
balanced system.
Achieves a smooth, rapid flow of
materials through the system
Eliminate disruptions
Make system flexible
Eliminate waste, especially excess
inventory
Summary of JIT Goals and
Building Blocks
Ultimate
A
Goal balanced
rapid flow
Supporting
Goals
Eliminate disruptions
Make the system flexible
Product
Design
Process
Design
Eliminate waste
Personnel
Elements
Manufacturing Planning
Building
Blocks
Big vs. Little JIT
 Big
JIT – broad focus
 Vendor
relations
 Human relations
 Technology management
 Materials and inventory management
 Little
JIT – narrow focus
 Scheduling
materials
 Scheduling services of production
What JIT Does
 Eliminates
waste
 Achieves streamlined production
 Eliminate disruptions in production …
caused by poor quality, schedule
changes, late deliveries.
 Makes the manufacturing delivery
system flexible by allowing it to handle a
variety of products and changes in the
level of output
 Reduces setup and delivery times
Eight Wastes
THE EIGHT TYPES OF WASTE OR MUDA
Waste
Definition
1. Overproduction
Manufacturing an item before it is needed.
2. Inappropriate
Processing
Using expensive high precision equipment when simpler machines
would suffice.
3. Waiting
Wasteful time incurred when product is not being moved or
processed.
4. Transportation
Excessive movement and material handling of product between
processes.
5. Motion
Unnecessary effort related to the ergonomics of bending,
stretching, reaching, lifting, and walking.
6. Inventory
Excess inventory hides problems on the shop floor, consumes
space, increases lead times, and inhibits communication.
7. Defects
Quality defects result in rework and scrap, and add wasteful costs
to the system in the form of lost capacity, rescheduling effort,
increased inspection, and loss of customer good will.
8. Underutilization of
Employees
Failure of the firm to learn from and capitalize on its employees’
knowledge and creativity impedes long term efforts to eliminate
waste.
Sources of Waste
 Overproduction
 Waiting
time
 Unnecessary
 Processing
 Inefficient
 Product
transportation
waste
work methods
defects
Strategies For Minimizing
Waste By Using JIT
 Manufacturing
in smaller lot sizes
reduces excess inventory
 Reducing inventory levels allows the
problems to be uncovered … thus
creating opportunities for
manufacturing process
improvement
Principles Of JIT Manufacturing
 Total
Quality Management
 Production
 Supplier
Management
 Inventory
 Human
Management
Management
Resource Management
1st Principle Of JIT
Total Quality Management
Total Quality Management
 Seek
long-term commitment to
quality efforts with continuous
improvement
 Quality
cost
must be a higher priority than
 Minimizing
waste
Total Quality Management
 Eliminate
 Quality
 Do
Quality Inspectors
is everyone’s responsibility
it right the first time
2nd Principle Of JIT
Production Management
Production Management
 Pull
System vs. Push System
 Pull
= Made to order
 Push = Made for inventory
 Flexibility
of the system
 Design
For Testability – In the
process
 Poka-Yoke=
Mistake-proofing
 Throughout entire process
Production Management
 Reduced
lot sizes= Shorter cycle times
 Eliminate
disruptions in the process
 Standardized
Parts/ Simplicity
Production Management

Communication Techniques
 Completion
of task-Kanban
 Problem- Siren/light
 Stopping
the process if something
goes wrong =Jidoka
 Preventive
Maintenance
3rd Principle Of JIT
Supplier Management
Supplier Management
 Establish
Long Term Relationships
with few suppliers.
 Delivery
 Where
of Parts = 100% Defect Free
they are needed
 When they are needed
 The exact quantity
 Work
Together
Supplier Management
 Elimination
inspection of parts
 Communicate
problems to suppliers
in a positive manner.
4th Principle Of JIT
Inventory Management
Inventory Management
 Eliminate
 JIT
Safety Stock = Zero Inventory
is not an inventory control system
 Reduction
space
in inventory opens up
 Inventory
process.
 Water
hides problems in a
Level = Inventory
 Rocks = Problems in the system
 Boat = Company Operations
5th Principle Of JIT
Human Resource Management
Human Resource
Management
 Company-wide



Involvement
Motivation for continuous improvement
Problem Solving
High Employee Interaction
 Build
Pride In Workmanship
Human Resource
Management
 Self-Inspection
 Diversified
of work
Employees
 Absenteeism
 To
eliminate boredom in process
 Management
Support and
Empowerment of workforce
JIT Manufacturing Building Blocks
 Product
design
 Process
design
 Personnel/organizational
elements
 Manufacturing
planning and control
1. Product Design
 Standard
 Design
 Highly
parts
Simplification
capable production systems
 Concurrent
engineering
Design Simplification
2. Process Design
 Small
 Setup
lot sizes
time reduction
 Limited
work in process
 Quality
improvement
 Production
 Little
flexibility
inventory storage
Benefits of Small Lot Sizes
Reduces inventory
Less rework
Less storage space
Problems are more apparent
Increases product flexibility
Easier to balance operations
Quality Improvement
 Autonomation

Automatic detection of defects during production
 Jidoka

Japanese term for autonomation
Production Flexibility
 Reduce
downtime by reducing
changeover time
 Use
preventive maintenance to
reduce breakdowns
 Cross-train
workers to help clear
bottlenecks
 Use many small units of capacity
 Reserve capacity for important
customers
3. Personnel/Organizational
Elements
 Workers
as assets
 Cross-trained
 Continuous
 Leadership
workers
improvement
4. Manufacturing Planning
and Control
 Pull
systems
 Visual
systems (kanban)
 Close
vendor relationships
 Reduced
transaction
processing (delays in
delievery)
 Preventive
maintenance
 Evaluation
and selection of vendor
(suppliers) network to develop a tiered
supplier network – reducing the number of
primary suppliers.
Transitioning to a Successful JIT
System
 Get
top management commitment
 Decide
which parts need most effort
 Obtain
support of workers
 Start
by trying to reduce setup times
 Gradually
convert operations
 Convert
suppliers to JIT
 Prepare
for obstacles
Obstacles to Conversion
 Management
may not be committed
 Workers/management
cooperative
 Suppliers
may resist
may not be
Comparison of JIT and Traditional
Factor
Traditional
JIT
Inventory
Much to offset forecast
errors, late deliveries
Minimal necessary to operate
Deliveries
Large
Small
Lot sizes
Large
Small
Setup; runs
Few, long runs
Many, short runs
Vendors
Long-term relationships Partners
are unusual
Workers
Necessary to do the
work
Assets
Comparison Of JIT & MRP











JIT
Repetitive production
Minimal shop floor control
Simpler
Relies on visual or audible signals to trigger production
and inventory (e.g. auto carpets)
Lower inventories related to need “at the time”
MRP
Lot size or batch production
Extensive shop floor control
More complex
Relies on computer system to trigger production and
order inventory Inventories related to batch or lot sizes
JIT in Services
The basic goal of the demand flow
technology in the service organization
is to provide optimum response to the
customer with the highest quality
service and lowest possible cost.
JIT Benefits
 Reduced
Inventory
 Improved quality
 Lower costs
 Reduced space requirements
 Shorter lead-time
 Increased productivity
 Greater flexibility
 Improved vendor relations
JIT Benefits (contd.)
 Simplified
scheduling & control
 Increased capacity
 Better utilization of personnel
 More product variety
 Increased equipment utilization
 Reduced paperwork
 Valid production priorities
 Work force participation
JIT … Not For Everyone
 JIT
concepts work best when goods can
be produced in response to consumer
demand (e.g. automobiles, etc.)
 JIT is less effective for the production of
standardized consumer goods (e.g. basic
clothing, food, soft drinks, toasters, etc.)
 There are cases where JIT concepts apply
to sub-processes of a make to stock
environment. (e.g. computers etc.)
References










Cammaranano, J. Lessons to be Learned: JIT. Atlanta, Georgia:
Engineering and Management Press, 1997.
Dear, A. Working toward JIT: Management Technology. London: Derek
Doyle and Associates, 1988.
Fisher, D. The JIT Self Test: Success Through Assesment and
Implementation. Chicago, IL: Irwin Inc., 1995.
Hernandez, A. JIT Quality: A Practical Approach. Englewood Cliffs, NJ:
Prentice-Hall, 1993.
Hutchins, D. Just-In-Time: Inventory Control. Brookfield, VT: Gower
Publishing, 1988.
O’Grady, P.J. Putting the JIT Philosophy Into Practice. New York, NY:
Nichols Publishing, 1988.
Reinfeld, N.V. Handbook of Production and Inventory Control.
Englewood Cliffs, NJ: Prentice-Hall, 1987.
Schneiderjans, M.J. Advanced Topics In JIT Management: JIT Systems.
Westport, CT: Greenwood Publishing Group, 1999.
Taver, R.W. Manufacturing Solutions for Consistent Quality and Reliability:
The 9 Step Problem Solving Process. New York, NY: AMACON, 1995.
Wesner, J.W., Hiatt, J.M., and Trimble, D.C. Winning with Quality: Applying
Quality Principles in Product Development. Reading, MASS: AddisonWesley Publishing Co., 1995.