Ch9 Jit
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Transcript of Ch9 Jit
Just-in-Time Systems
Reducing Variance, Waste and Lead Time in the Supply Chain
Topics to be Covered Review of JIT & Waste Objectives of JIT JIT Principles JIT and Variance JIT Tools and Procedures
JIT: Definitions? JIT Head Chicken JIT Oh JIT (O´JIT) Tough JIT Strate JITs
JIT Planes Bull JIT Le JIT JIT Lag When the JIT hits
the fan.
What is JIT?
a corporate system designed to produce output within the minimum lead time and at the lowest total cost by continuously identifying and eliminating all forms of corporate waste and variance.
a corporate strategy a philosophy Focus of JIT: • variance & waste
Waste Types
Chrysler Video on Waste
Seven Basic Types of Waste
Transportation waste Process Waste Inventory Waste Waste of motion Waste from product defects Waiting time Overproduction
Common Causes of Waste Layout (distance) Long setup time Incapable
processes Poor maintenance Poor work
methods Lack of training
Inconsistent performance measures
Ineffective production planning
Lack of workplace organization
Poor supply quality/reliability
Objective of JIT Produce only the products the
customer wants. Produce products only at the rate
that the customer wants them. Produce with perfect quality Produce with minimum lead time. Produce products with only those
features the customer wants.
Objectives Produce with no waste of labor,
material or equipment -- every movement must have a purpose so that there is zero idle inventory.
Produce with methods that allow for the development of people
JIT Principles
Create flow production • one piece flow
• machines in order of processes • small and inexpensive equipment • U cell layout, counter clockwise • multi-process handling workers • easy moving/standing operations • standard operations defined
JIT Principles - Slide 2 Establish “TAKT” time • rate at which the customer
buys a product Build Pull Product • use of kanban system
JIT Tactics Single Minute
Exchange of Dies (SMED)
Statistical Process Control
Use of standard containers
Doable stable schedules with adequate visibility
TAKT-Time 5-S Program Kaizen Event
Visual control Flexible workers Tools at the point of
need Product redesign Group Technology Total Productive
Maintenance
Balanced Production Three elements • TAKT time • Work sequence • Standard WIP Objective • Build at rate that the customer wants
work • Balance the system to maximize efficiency at this rate
TAKT Time Example Net Available Operating Time • Time per shift 480´ (minutes) • Breaks (2 @ 10´) - 20´ • Clean-up - 20’ • Lunch - 30’ • NAOT/shift 410´ Customer Requirements • Monthly 26,000 units/month
• No. Working Days 20 days/month • CR/Day 1,300 units/day TAKT Time • 410’ x 60” x 3 shifts (73,800) divided by
1,300 • 57.769 seconds per part or 57"
TAKT Time TAKT • the beat • (Net Available Operating
Time) / Customer Requirements • time periods must be
consistent Example of calculation
SMED Setup reduction Elements • Internal Setup • setup while machine idle • External Setup • setup while machine busy • Adjustment • run-ins, calibration
SMED Process Study current process • “as is” • video tape • Who owns the video tape? Convert internal to external setup Eliminate the need for Adjustment Eliminate need for fastening Goal • setup time < 10 minutes
Push Vs. Pull Scheduling Push Scheduling • traditional approach • “move the job on when finished” • problems - creates excessive inventory Pull scheduling • coordinated production • driven by demand (pulled through
system) • extensive use of visual triggers (production/withdrawal kanbans)
Visual Control A system for making problems obvious
without the need for sophisticated monitoring computer systems
• Andon light system • Kanbans Create a sense of urgency Clearly identify where the problems are
located
Supplier Partnerships Reliance on suppliers for • problem solving expertise • quality at the source • timely communication • participants in cost reduction
programs Increased reliance on supplier
certification
Standardization/Simplification Eliminate inherent sources of variance eliminate opportunity for human discretion
error Examples • Container sizes • MacDonalds with interaction with
customers Consistent with Deming Wheel • Standarize expose problems solve problems implement new methods
Other Techniques Milk runs Poka-Yoke Systems Continuous Improvement Programs
(CIP)
Video
JIT at McDonalds
JIT - Day 2
New Developments in JIT
JIT & Lean Manufacturing Lean Manufacturing • Doing more with less • Less of: • materials, time, resources • overhead, people • waste • money JIT is a subset of Lean
Manufacturing Now seen as most applicable to
mass production settings
Kaizen Event A relatively new concept • Kaizen Blitz, Gemba Kaizen Process focused Operates at two levels • on-going process of identifying
opportunities for improvement
• strategic, top management
•short-term project lasting 1-4 days • training, documentation of process “as is”,
identification of potential improvements, implementation, presentation, action list
Kaizen Events - Key Traits Very short-term, finite in life Highly focused Creativity before capital Team-oriented Action-Oriented Verifiable Metrics Repetitive
Kaizen Event Process Top management buy-in • Public Kaizen Events Assessment of current processes • top management
• Target Processes • training • documentation - “as is” • opportunities • change • presentation/action list
Typical Metrics Floor space occupied by process being
assessed Operators required per day Distance traveled by an order within the
process WIP Inventory Setup (measured in minutes) Quality recommendations generated Safety Improvements implemented
Application of Kaizen Events Shop floor Finance • 401 K plan Purchasing Health Care Services
Example of Impact of Kaizen Event Impact of Kaizen Events - Overall Benefits (January 1, 1996 through December 31, 1996
Improvement M________ Before Kaizen Achievement Improvement
Floor Space ( ) 56,000 39,000 30%
Operators/Day 165 125 24%
Distance Traveled 91,000 ft. 15,000 ft. 34%
Inventory (WIP pieces) 4,760,000 2,570,000 46%
Setup Time Reduction 1,660 _______ 1,660 _________ 72%
Safety Improvements 200 improvements implement
JIT 11 Based on system developed by
Bose of Framingham, MA Integration of JIT principles and
practices into the supply chain JIT II • long term collaborative relationships
with suppliers present • suppliers to place personnel in plants
of the buying organization
Limitations of JIT Preconditions to JIT • trust must be present • labor/management • suppliers/consumers
• recognition of processes • familiarity with problem solving • quality at the source • agreement over value and waste
Limitations of JIT Right Settings • applicable in growth to maturity phases of Product Life Cycle • standard product • Steinway and JIT
• standard/fixed pay-rate • problems with piece-rate scheme Universal agreement that change
needed
Theoretical Benefits of JIT Unpleasant surprises
eliminated Less
computerization • visual control Improved quality WIP reduced Better
communications
Less pressure on receiving docks and incoming inspection areas
Lower costs Change in attitude • Defects are
treasures
Dealing with Variance Four major stances: • Buffer against it • Ignore it • Manage it • Eliminate it All forms of variance create cost
JIT & Variance Variance a fact of life Comes from many sources • internal scheduling changes, scheduling practices,
manufacturing planning & control systems,
absenteeism, process variability
• external changes in forecasts, actual demand, customer
requested changes, government, competition, vendors
Cycle Times Operator Cycle Time • total time required for a worker to complete one cycle of an operation Machine Cycle Time • total time for a machine to finish
one complete cycle • includes loading and unloading
Some Interesting Calculations • No. of Operators • Sum OCT/(TAKT TIME) • Example • OCT for Operator 1 = 13" • OCT for Operator 2 = 9" • OCT for Operator 3 = 11" • OCT for Operator 4 = 10" • Total 43"
• TAKT Time 16.5" • Number of Operators • 43/16.5 = 2.606 or 3 operators
The 5-S Program
Seiri • segregate and discard • get rid of what is not needed Seiton • arrange and identify for ease of use • a place for everything and everything
in its place Seiso • Clean Daily • clean work place enhances quality
The 5-S Program Seiketsu • Revisit frequently • revisit the first 3 steps to maintain
workplace safety and effectiveness Shitsuki • Motivate to sustain • promote adherence through visual
performance measurement tools
Next Day JIT in Service Sectors New developments in JIT • Lean Manufacturing • Agile Enterprise • JIT II • Gemba Kaizen • Quick Response Systems
Topics to be Covered JIT and Lean Manufacturing JIT in Services Kaizen Events JIT II Gemba Kaizen Agile Enterprise Limitations of JIT
JIT in Services Service Traits • strong emphasis on process • avoidance of inventory • emphasis on people and their
importance to process • recognition of need for continuous
improvement • “defects are treasures”
JIT in Services Elements of JIT most applicable • Synchronization and balance of
information and work flows • Total visibility of all components of the
process • Continuous improvement of the process • Holistic approach to the elimination of
waste • Flexibility in use of resources • Respect for people
JIT in Services Key Issues • Equipment/people focus • Customer contact per transaction • Degree of discretion • Degree of customization • Location of value-added processes • Product/process focus
Gemba Kaizen
Waste reduction through the execution system
Gemba • heart of the system Essence of Gemba Kaizen • to eliminate waste, you must have
contact with the system that you are managing
• the contact must be real and not through
computers
Agile Enterprise New development Associated with Iaccoca Institute of
LeHigh University Merging flexibility with JIT Much broader than Lean Enterprise Recognition that the environment • always changing
• unpredictably undergoing change
Agile Enterprise - Traits Rapidly bring to market products that
are variable combinations of hardware, information and services.
Design products that are easily configurable and ungradable.
Produce to individual customer orders in arbitrary order quantities.
Bring out a continuously changing array of models within longer-lived product families
Agile Enterprise - Traits Fragment mass markets into niche
markets. Maintain and foster continuous, rather
than single-instance, sales relationships by continually adding value to current customers.
Cooperate intensively with other companies, including competitors, to create global product resources.
Agile Enterprise
Attempt to bring together a number of different trends
• greater focus on product development • greater reliance on suppliers • greater concern with speed • more emphasis on effective and
intelligent integration • greater use of technology • information
Other Tactics Kaizen/Continuous Improvement Manufacturing Cells Business Process Reengineering Milk run logistics Supplier certification Direct delivery to point of use