Buddha Bahadur Shakya

JIT and Lean

Operations

Toyota Production System (TPS)

• Toyota's development of ideas that later became lean may have started at the turn of the 20th century, in a textile factory with looms that stopped themselves when a thread broke.

• This became the seed of autonomation and Jidoka.

• Toyota's journey with JIT may have started back in 1934 when it moved from textiles to produce its first car.

Toyota Production System (TPS)

• Kiichiro Toyoda, founder of Toyota Motor Corporation, directed the engine casting work and discovered many problems in their manufacture.

• He decided he must stop the repairing of poor quality by intense study of each stage of the process.

• In 1936, when Toyota won its first truck contract with the Japanese government, his processes hit new problems and he developed the "Kaizen" improvement teams.

Toyota Production System (TPS)

1. (Kaizen) Continuous Improvement

2. Respect for People

– Training, empowerment

3. Standard Work Practice

– Work is completely specified as to content, sequence, timing and outcome.

Lean Operations

• Lean operations began as lean manufacturing in the mid-1900s.

• It was developed by Toyota.• Toyota’s focus was on elimination of waste.• In mid 1980s, revival of GM auto plant at

Fremont, California under joint venture of Toyota & GM called New United Motor Manufacturing Inc. (NUMMI).

Lean Operation• The term was first coined by John Krafcik in his 1988 article,

"Triumph of the Lean Production System," based on his master's thesis at the MIT Sloan School of Management.

• Krafcik had been a quality engineer in the Toyota-GM NUMMI joint venture in California before coming to MIT for MBA studies.

• Krafcik's research was continued by the International Motor Vehicle Program (IMVP) at MIT, which produced the international best-seller book co-authored by Jim Womack, Daniel Jones, and Daniel Roos called The Machine That Changed the World.

JIT and Lean Operations

Just-in-time (JIT)• A highly coordinated

processing system in which goods move through the system, and the services are performed, just as they are needed.

Lean Operation• A highly coordinated

system that uses minimal resources and produces high quality goods or services depending on high quality process.

• Now the two terms are often used interchangeably .

Terms associated with lean operations

1. Muda: – Waste and inefficiency.

2. Kanban:– Each container holds a small supply of parts

or materials. New containers are delivered to replace empty containers.

– A manual system used for controlling the movements of parts and materials that responds to signals of the need for delivery of parts or materials.

3. Pull system:– Replacing materials or parts based on

demand; produce only what is needed.

Terms associated with lean operations4. Kaizen:

– Continuous improvement of the system. There is always room for improvement, so this effort must be ongoing.

5. Jidoka (Autonomation):

– Quality at the source. Automatic detection of defects during production. Detecting defects when they occur and stopping production to correct the cause of the defects.

– The objective is to avoid passing defective products to following work stations, and to make workers aware of quality.

6. Poka-yoke:

– Safe guards built into a process to reduce the possibility of committing an error.

Terms associated with lean operations7. Heijunka:

– Variation in production volume lead to waste.

– The work load must be leveled; volume and variety must be averaged to achieve a steady flow of work.

8. Team concept:– Use small teams of worker for process improvement.

9. Muri – "overburden” and

10. Mura – “unevenness”

Terms associated with lean operations11. Andon:

Each workstation is equipped with a set of three lightsA green light means no problemAn amber light means a worker is falling a little bit behindA red light indicates a serious problem.

Goals and Building Blocks of Lean System

1. Eliminate disruptions

• Caused by1. Poor quality2. Equipment breakdowns3. Changes to schedule4. Late deliveries

2. Make the system flexible

DEFINITION• A system that is robust enough

– to handle a mix of products, often on a daily basis and

– to handle changes in the level of output – while maintaining balance and throughput speed.

• Requirement for flexibility– Short setup time– Short lead time

3. Eliminate Waste Waste is anything that does not add value

from the customer point of view.

Storage,

Inspection,

Delay,

Waiting in queues, and

Defective products do not add value and are 100% waste.

Taiichi Ohno’s Seven Wastes

1. Overproduction

2. Queues

3. Transportation

4. Inventory

5. Motion

6. Over processing

7. Defective products

Wastes

Other resources such as energy, water, and air are often wasted.

Efficient, ethical, and socially responsible production minimizes inputs, reduces waste.

Traditional “housekeeping” – for a neat, orderly and efficient workplace.

Waste in Operations

Waste in Operations

Waste in Operations

Kaizen Philosophy for eliminating waste

1. Waste is the enemy.2. Improvement should be done gradually

and continuously.3. Everyone should be involved.4. Built on a cheap strategy.5. Can be applied anywhere.

Kaizen Philosophy for eliminating waste

6. Supported by a visual system: a total transparency of procedures, processes and values, making problems and wastes visible to all.

7. Focuses attention where value is created8. Process oriented9. Stresses main effort of improvement should

come from new thinking and work style.10.The essence of organizational learning is to

learn while doing.

Product Design:•Standard parts•Modular design•Quality•Concurrent engineering

Product Design:•Standard parts•Modular design•Quality•Concurrent engineering

Process Design:•Small lot sizes•Setup time reduction•Manufacturing cells•Quality improvement•Production flexibility•A balanced system•Little inventory storage•Fail-safe methods

Process Design:•Small lot sizes•Setup time reduction•Manufacturing cells•Quality improvement•Production flexibility•A balanced system•Little inventory storage•Fail-safe methods

Personnel/Organizational Elements:•Workers as assets.•Cross-trained workers•Continuous improvement•Cost accounting•Leadership/project management

Personnel/Organizational Elements:•Workers as assets.•Cross-trained workers•Continuous improvement•Cost accounting•Leadership/project management

Manufacturing Planning Control:•Level loading•Pull systems•Visual systems•Limited WIP•Closed vendor relationship•Reduced transaction processing•Preventive maintenance & housekeeping

Manufacturing Planning Control:•Level loading•Pull systems•Visual systems•Limited WIP•Closed vendor relationship•Reduced transaction processing•Preventive maintenance & housekeeping

1. Eliminate disruptions √2. Make the system flexible √

3. Eliminate waste √

A balanced rapid flow

Ultimate Goal

Supporting Goals

JIT Building Blocks

1. Product design

2. Process design

3. Personnel/organizationalelements

4. Manufacturing planning and control

1. Product Design

• Modular design• Reduces the number of parts to deal with.• Simplifies assembly, purchasing, handling,

training.• Simplifies the bill of material.

• Quality (Product, Process)• Concurrent engineering

• Standard parts• Fewer parts to deal with.• Training times and costs are reduced.• Purchasing, handling and checking quality are more routine.

2. Process Design

1. Small lot sizes2. Setup time reduction3. Manufacturing cells4. Quality improvement5. Production flexibility6. A balanced system7. Little inventory storage8. Fail-safe methods

A

A A B B B C

JIT Small Lots

Large-Lot Approach

Time

Time

A A B B B C

A A A B B B B B B C C

JIT produces same amount in same time if setup times are lowered

2.1 Small-Lot Production

Small lots also increase flexibility to meet customer demands

Comparison of Comparison of Level and Large Lot Material-use ApproachesLevel and Large Lot Material-use Approaches

Reduce Lot SizesReduce Lot Sizes

200 –

100 –

Inve

nto

ry

Time

Q2 When average order size = 100average inventory is 50

Q1 When average order size = 200average inventory is 100

Benefits of small lot sizes

1. Reduced inventory, lower carrying cost.

2. Less space required to store inventory.

3. Less rework if defects occur.

4. Less inventory to “work off” before implementing product improvements.

5. Increased visibility of problems.

6. Increased production flexibility.

7. Increase ease of balancing operations.

2.2 Setup time reduction• Small lots and changing product mixes require

frequent setups.

• Unless these are quick and inexpensive the time and cost to accomplish them can be prohibitive.

• Setup time can be reduced through

– Preparation prior to shutdown and changeover.– Simple and standardized setup tools and

equipment.– Multipurpose equipment or attachment.– Group technology

Single-Minute Exchange of Die (SMED)

• Developed by Shigeo Shingo• First categorize changeover activity as

“internal” and “external”.• Internal activities can only be done while a

machine is stopped.• External activities are those that do not involve

stopping the machine.• Convert as many internal activities as possible

to external activities.

Reduce Setup Times

Use one-touch system to Use one-touch system to eliminate adjustments (save eliminate adjustments (save 10 minutes)10 minutes)Step 4Step 4

Step 5Step 5Training operators and Training operators and standardizing work procedures standardizing work procedures (save 2 minutes)(save 2 minutes)

Initial Setup Time

Step 2Step 2Move material closer and improve material handling

(save 20 minutes)

Step 1Step 1

Separate setup into preparation and actual setup, doing as much as possible while the

machine/process is operating (save 30 minutes)

Step 3Step 3

Standardize and improve tooling (save

15 minutes)

90 min 90 min

60 min60 min

40 min 40 min

25 min 25 min

15 min 15 min

13 min 13 min

——Repeat cycle until Repeat cycle until subminute setup is achievedsubminute setup is achieved

Step 6Step 6

Lower Setup CostsLower Setup Costs

Sum of ordering and holding costs

Holding cost

Setup cost curves (S1, S2)T1

S1

T2

S2

Co

st

Lot size

High setup costs encourage large lot sizes.

Reducing setup costs reduces lot size and reduces average inventory.

Determination of Set Up time

p

u1H

DS2Q

up

p

H

DS2Q

0

0

D2

p

u1HQ

S

p

u1H

DS2Q

p

u1H

DS2Q

20

20

0

Set up time = Set up cost / (hourly labor rate)

2.3 Manufacturing cells

• Cells containing the tools and machines needed to process families of parts having similar processing requirements.

• Benefits– Reduced changeover time– High utilization of equipment– Ease of cross training operators

Cellular LayoutsJIT objective: Reduce movement of people and material

Movement is waste! JIT requires work-cells for product families (group

technology) movable, changeable, flexible machinery short distances high level of workplace organization and neatness Improve employee communication Use poka-yoke devices Cross train workers to add flexibility to layout Balanced workstation capacities

Cellular Layouts

Group dissimilar machines in manufacturing cell to produce family of parts

Work flows in one direction through cell Cycle time adjusted by changing worker paths Decreasing set-up times

2.4 Quality Improvement

JIT exposes quality problems by reducing inventory. JIT eliminates number defects with small lots. JIT requires quality by suppliers. Team approach and continuous improvement are important

for ensuring quality. Quality is maintained by the following procedure:

Find the root cause of the problem, solve permanently and use team approach in solving the problems

Quality Improvement

JIT requires TQM Statistical process control Worker involvement & empowered employees Inspect own work Quality circles Immediate feedback

Fail-safe methods such as poka-yoke (prevents defectives)

Quality Improvement

1. Jidoka (Autonomation) assures quality at the source

2. Andon lights signal quality problems

Visual Control

Visual control makes problems visible.

Visual Control

Visual Control

2.5 Increasing Production Flexibility

1. Reduce downtime due to changeovers by reducing changeover time.

2. Use preventive maintenance on key equipment to reduce breakdowns and downtime.

3. Cross-train workers so they can help when bottlenecks occur or other workers are absent.

4. Train workers to handle equipment adjustments and minor repairs.

2.5 Increasing Production Flexibility

4. Use many small units of capacity;

many small cells make it easier to shift capacity temporarily and to add or subtract capacity than a few units of large capacity.

5. Use off-line buffers.

Store infrequently used safety stock away from the production area to decrease congestion and to avoid continually turning it over.

6. Reserve capacity for important customers.

Streamlined Production

Flow with JIT

Traditional Flow

CustomersSuppliers

Customers

Suppliers

Production Process (stream of water)

Inventory (stagnant ponds) Material

(water in stream)

2.6 A Balanced System

• Balanced system:

– Distributing the workload evenly among work stations

• Work assigned to each work station must be less than or equal to the cycle time.

• Cycle time is set equal to the takt time.

• Takt time is the cycle time needed to match the pace of production to customer demand for final product.

Takt time• Total time = 480 minutes• Rest Breaks = 40 minutes• Lunch = 30 minutes

• Net time available= 410 minutes/shift * 2 shifts/day= 820 minutes per day

• Takt time = (Net time available per day)/( Daily demand) = (820 minutes per day) /(80 units per day) = 10.25 minutes per cycle

Traditional: inventory exists in case problems arise JIT objective: eliminate inventory JIT requires

Small lot sizesLow setup timeContainers for fixed number of parts

JIT inventory: Minimum inventory (raw material, WIP and finished goods) to keep the system running

Specialized bins for holding previously set number of parts

2.7 Inventor2.7 Inventoriesies

JIT Inventory Tactics

Use a pull system to move inventory

Develop Just-in-Time delivery systems with suppliers

Deliver directly to point of use

Perform-to-schedule

Use group technology

Limited Work in Process

• Benefits– Lower carrying costs.– Less space.– Increased flexibility.– Aids scheduling.– Saves cost of rework and scrap.

Inventory Hides Problems Just as Inventory Hides Problems Just as Water in a Lake Hides RocksWater in a Lake Hides Rocks

Unreliable supplier

Setup time

Late deliveries

Quality problems

Process downtime

Setup time

Late deliveries

Quality problems

Process downtime

Inventory level

Inventory level

İnefficient layout

Bad design Machine

breakdownBad design

İnefficient layout

Unreliable supplier

Machine breakdown

Scrap

Work in process inventory level(hides problems)

Unreliable Vendors

Capacity Imbalances

Lowering Inventory Reduces WasteLowering Inventory Reduces Waste

Scrap

Reducing inventory exposes problems so they can be solved.

Unreliable Vendors

Capacity Imbalances

WIP

Lowering Inventory Reduces WasteLowering Inventory Reduces Waste

Scrap

Reducing inventory revealsReducing inventory revealsproblems so they can be solved.problems so they can be solved.

Unreliable Vendors

Capacity Imbalances

WIP

Lowering Inventory Reduces WasteLowering Inventory Reduces Waste

2.8 Fail-Safe MethodsJapanese call this Poka-yoke. (Shingeo Shingo)

Examples:An alarm that sounds if the weight of a packaged item is too low.

Putting assembly components in “egg cartoons” to ensure that no parts are left out.

Designing parts that can only be attached in correct position.

In a vehicle, signals that warn: The key is still in the ignition if the car door is opened If door is ajar, Seatbelts are not fastened, Fuel level is low

ATM signal if a card is left in a machine.Detectors at departmental store if a monitoring tag hasn’t been removedComputer passwordElectrical fuses and circuit breakers

3. Personnel/Organizational Elements

1. Workers as assets

2. Cross-trained workers

3. Employee empowerment

4. Continuous improvement

5. Cost accounting

6. Leadership/project management

7. Commitment

Workers as assets

• Well trained and motivate workers are the heart of a JIT system

• Workers are given more authority to make decisions.

Cross-trained workers

• Workers are cross trained to perform several parts of a process and operate a variety of machines.

• This adds system flexibility because workers are able to help one another when bottlenecks occur or when a coworker is absent.

• It also helps line balancing.

Employee Empowerment

• Empowered and cross-trained employees (to help clear bottlenecks).

• Get employees involved in product & process (employees know the job best!).

• Few job classifications to ensure flexibility of employees.

• Training support.

Continuous improvement• JIT workers receive extensive training in

statistical process control, quality improvement, and problem solving.

• Continual improvement of the system– Reducing inventories– Reducing setup cost & time– Improving quality– Increasing the output rate– Cutting waste and inefficiency

Cost accounting• Activity based costing

– Allocation of overhead to specific jobs based on their percentage of activities.

– First identifies traceable costs– Assigns those costs to various types of activities such

as machine set up, inspection, machine hours, direct labor hours and movement of materials.

– Specific jobs are then assigned overhead based on the percentage of activities they consume.

Leadership/project management

• Managers are supposed to be leaders and facilitators not order givers.

• Support of management, employees and suppliers

• Any improvement must be made in accordance with the scientific method, under the quidance of a teacher, at the lowest possible level in the organization

(Toyota Production System’s work rule)

4. Manufacturing Planning and Control

• Level loading (level schedules)

• Pull systems

• Visual systems

• Limited work-in-process (WIP)

• Closed vendor relationship

• Reduced Transaction processing

• Preventive maintenance & housekeeping

Reduce ripple effect of small variations in schedules (e.g., final assembly)

Production quantities evenly distributed over time (e.g., 7/day)

Build same mix of products every day Results in many small lots ItemMonthly Quantity Daily Quantity

A 40 2B 60 3

4.14.1 Level SchedulesLevel Schedules

Mixed-Model SequencingModel Daily Quantity Units per cycle

A 10 10/5 = 2B 15 15/5 = 3C 5 5/5 = 1

Three issues that need to be resolved

1. Which sequence to use?

2. How many times the sequence should be repeated daily?

3. How many units of each model to produce in each cycle?

Mixed-Model SequencingModel Daily Quantity Units per cycle

A 7 10/5 = 1.4B 16 15/5 = 3.2C 5 5/5 = 1

Cycle 1 2 3 4 5

Pattern A B(3) C A(2) B(3) C A B(4) C A B(3) C A B(3) C

Extra units A B A

Cycle 1 2 3 4 5

Pattern A(2) B(3) C A B(3) C A(2) B(4) C A B(3) C A(2) B(3) C

Extra units A AB A

A = 8, B = 16, C = 5

Mixed-Model Sequencing

4.2 Pull/Push Systems

Pull system:

System for moving work where a workstation pulls output from the preceding station just as it is needed. (e.g. Kanban)

Push system:

System for moving work where output is pushed to the next station as it is completed.

Push System

• Every worker maximizes own output, making as many products as possible

• Pros and cons:– Focuses on keeping individual operators and workstations

busy rather than efficient use of materials.– Volumes of defective work may be produced.– Throughput time will increase as work-in-process increases

(Little’s Law).– Line bottlenecks and inventories of unfinished products will

occur.– Hard to respond to special orders and order changes due to

long throughput time.

The Pull System

Material is pulled through the system when needed(JIT).

Reversal of traditional push system where material is pushed according to a schedule

Forces cooperation

Prevent over and underproduction

4.3 Visual systems• In a pull system work flow is dictated by “next-step

demand”.• A system can communicate such demand in a variety of

ways, including a shout or a wave.• Most commonly used device is

– KANBAN Card

74

Kanban Example

Workcenter B uses parts produced by Workcenter A

How can we control the flow of materials so that B alwayshas parts and A doesn’t overproduce?

Workcenter A Workcenter B

75

When a container is opened by Workcenter B, its kanban card is removed and sent back to Workcenter A.This is a signal to Workcenter A to produce another box of parts.

Kanban card: Signal to produceWorkcenter A Workcenter B

Kanban Card

KanbanKanban

Kanban

Kanban

Final assembly

Work cell

Kanban

Material/Parts Supplier Finished

goodsCustomer

order

KanbanKanban

1. User removes a standard sized container

2. Signal is seen by the producing department as authorization to replenish

Part numbers mark location

Signal marker on boxes

Kanban Production Control System

Japanese word meaning “signal” or “visible record” may be a card, or may be a flag, ball etc.

Paperless production control system

Kanban card indicates standard quantity of production

Used often with fixed sized container

Kanban: Card or other device that communicates demand for work or materials from the preceding station.

Kanban Production Control System

The kanban cards provide direct control (limit) on the amount of work-in-process between cells.

Derived from two-bin inventory system

Maintains discipline of pull production

Signifies an authority to pull or produce which comes from a downstream process

Production kanban authorizes production

Withdrawal kanban authorizes movement of goods

Determination of the Number of Kanbans-formula

(N) Total number of kanbans =Demand during lead time + Safety Stock

Size of container

• Daily demand = 500 cakes

• Production lead time = wait time + material handling time + processing time = 2 days

• Safety stock = ½ days

• Container size = 250 cakes

(N) Total number of kanbans =2 days * 500 cakes/day + 250

250

= 5

Example:

Determination of the Number of Kanbans-Formula

N = DT(1+X)C

N = Total number of containers

D = Planned usage rate of using work center

T = Average waiting time for replenishment of parts plus average

production time for a container of parts

X = Policy variable set by management possible inefficiency in the

system

C = Capacity of a standard container

Determination of the Number of Kanbans-Formula

N = DT(1+X)C

N = Total number of containers = ?

D = Planned usage rate of using work center = 300 parts per day

T = Average waiting time for replenishment of parts plus average

production time for a container of parts = 0.12 day

X = Policy variable set by management possible inefficiency in the

system = 0.20

C = Capacity of a standard container = 25 parts per container

4.4 Limited Work-In-Progress (WIP)

• Little’s Law: – WIP = Cycle Time X Arrival Rate

• There are two general approaches to controlling WIP– Kanban, CONWIP

• CONWIP: a job exits the system, a new job is allowed to enter.

4.5 Closed Vendor Relationship

• Buyers work with vendors to help them achieve the desired quality levels.

• Suppliers also must be willing and able to ship in small lots on a regular basis.

• Local vendors to shorten the lead time for deliveries and to reduce lead time variability.

• Long term relationship between buyers and vendors.

Supplier Relationships

Reduced number of vendors. Supportive supplier relationships. Quality deliveries on time. Frequent deliveries in small lot quantities. Reduced lead times. Reduced transaction processing. Certified vendors.

JIT PartnershipsJIT Partnerships JIT partnerships exist when a supplier and

purchaser work together to remove waste and drive down costs

Four goals of JIT partnerships are: Removal of unnecessary activities

Removal of in-plant inventory

Removal of in-transit inventory

Improved quality and reliability

Nearby

Analysis and support to enable desirable suppliers to become or stay price competitive.

Buyer resists vertical integration and subsequent wipeout of supplier business.

Suppliers encouraged to extend JIT to their suppliers (2nd and 3rd tier suppliers)

Characteristics of JIT PartnershipsCharacteristics of JIT Partnerships

Traditional Supplier Network

BuyerBuyer

SupplierSupplierSupplierSupplier SupplierSupplier SupplierSupplier

SupplierSupplier

SupplierSupplierSupplierSupplier

Tiered Supplier Network

SupplierSupplier

SupplierSupplier

SupplierSupplier

SupplierSupplierSupplierSupplier SupplierSupplier

BuyerBuyer

SupplierSupplierFirst Tier Supplier

Second Tier Supplier

Third Tier Supplier

JIT PartnershipsJIT Partnerships

4.6 Reduced Transaction Processing

• Logistical transactions– Ordering, execution, confirmation of materials

transported from one location to another.– Costs: shipping, receiving personnel, expediting

orders, data entry, data processing.

• Balancing transactions– Forecasting, production planning, production

control, procurement scheduling, order processing– Costs: cost of personnel involved in above activities

Reduced transaction processing

• Quality transactions– Determining and communicating specifications, monitoring,

recording– Costs: appraisal, prevention, internal failures, external

failures

• Change transactions– Ensuing changes generated in specification, bill of materials,

scheduling, processing instructions– Costs: co.st of engineering changes

4.7 Preventive Maintenance

All activities involved in keeping equipment in working order

Maintaining equipment in good condition and replacing parts that have a tendency to fail before they actually fail

Done to prevent failure

JIT requires

Scheduled & daily PM

Operator involvement in PMKnows machinesResponsible for product quality

Total Productive Maintenance (TPM)

Breakdown maintenanceRepairs to make failed machine operational

Preventive maintenanceSystem of periodic inspection & maintenance

to keep machines operatingTPM combines preventive maintenance & total

quality concepts

TPM Requires Management to:

Design products that can be easily produced on existing machines.

Design machines for easier operation, changeover, maintenance.

Train & retrain workers to operate machines.

Purchase machines that maximize productive potential.

Design preventive maintenance plan spanning life of machine.

Example 1• The cost of breakdown = Rs.1000• Cost of preventive maintenance = Rs 1250/month

• If preventive maintenance is performed, the probability of a machine breakdown is negligible.

• The frequency of breakdown of a machine per month is as shown in the table

Number of Breakdowns

Frequency of occurrence

Expected number of Breakdowns without PM

0 0.2 0

1 0.3 0.3

2 0.4 0.8

3 0.1 0.3

Total 1.0 1.4

• Expected cost using repair policy is 1.4 breakdowns/month X Rs1000/breakdown = Rs1400/month

• Cost of preventive maintenance = Rs 1250/month

• Preventive maintenance would yield a saving of Rs.150/month

Example -2 1. Average time before breakdown

1. Normally distributed

2. Mean of 3 weeks

3. Standard deviation of 0.60 week

2. Average breakdown cost = Rs. 1000

3. Preventive maintenance cost = Rs 250

4. What is optimal maintenance interval

67.0z25.01000

250

CostBreakdown

CosteventivePr

Optimal maintenance interval = Mean + z(Standard Deviation) = 3 – 0.67*(0.60) = 2.598 ≈ 2.6 weeks

4.7 Housekeeping

“Good factories develop beginning with the 5S’s. Bad factories fall apart beginning with the 5 S’s.”

- Hirouki Hirano

Japanese Translation English

Seiri Proper arrangement Sort

Seiton Orderliness Straighten

Seiso Cleanliness Sweep

Seiketsu Cleanup Standardize

Shitsuke Discipline Self-Discipline

Maintaining a workplace that is clean and free of unnecessary materials.

The 5 Ss + 2 SsThe 5 Ss + 2 Ss

Two additional Ss Safety – build in good safety practices

Support/maintenance – reduce variability and unplanned downtime and cost.

Summary: Summary: Just-In-Time ProductionJust-In-Time Production

• Management philosophy• “Pull” system though the plant

WHAT IT IS

• Employee participation• Industrial engineering/basics• Continuing improvement• Total quality control• Small lot sizes

WHAT IT REQUIRES

• Attacks waste• Exposes problems and bottlenecks• Achieves streamlined production

WHAT IT DOES

• Stable environment

WHAT IT ASSUMES

Comparison of JIT and Traditional Systems

Factor Traditional JIT

Inventory Much to offset forecast errors, late deliveries

Minimal necessary to operate

Deliveries Few, large Many, small

Lot sizes Large Small

Setup; runs Few, long runs Many, short runs

Vendors Long-term relationships are unusual

Partners

Workers Necessary to do the work

Assets

Transitioning to a JIT SystemGet 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 may not be cooperative

May be difficult to change company culture

Suppliers may resist

Why?

Suppliers May Resist JIT

Unwilling to commit resourcesUneasy about long-term commitmentsFrequent, small deliveries may be difficultBurden of quality control shifts to supplierFrequent engineering changes may result from

continuing JIT improvement by buyer.

Benefits of JIT

1. Reduced inventory2. Improved quality3. Lower costs4. Reduced space

requirements5. Reduced lead times6. Increased productivity7. Greater flexibility8. Reduced scrap and

rework

8. Better relations with suppliers

9. Simplified scheduling and control activities

10. Increased capacity11. Increased equipment

utilization12. Better use of human

resources13. More product variety14. Reduced need for

indirect labor

Lean Operations in ServicesLean Operations in Services

The JIT techniques used in manufacturing are used in services Suppliers

Layouts

Inventory

Scheduling

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 in ServicesJIT in Services

All the techniques used in manufacturing are used in services

Level the facility load & eliminate disruptions and unnecessary activities

Reorganize physical configuration

Introduce demand-pull scheduling

Develop supplier networks

Minimize WIP

JIT in ServicesJIT in Services

All the techniques used in manufacturing are used in servicesEliminate disruptionsMake the system flexibleReduce setup and lead timesEliminate wasteMinimize the work in progressSimplify the processOrganize problem solving groupsUpgrade quality

Big vs. Little JIT

Big JIT – broad focusVendor relationsHuman relationsTechnology

managementMaterials and inventory

management

Little JIT – narrow focus Scheduling materials Scheduling services for

production

JIT and Competitive AdvantageJIT and Competitive Advantage

JIT and Competitive AdvantageJIT and Competitive Advantage

• A supplier representative works right in the company’s plant, making sure there is an appropriate supply on hand.

• Often referred to as vendor-managed inventory (VMI)

• Popularized by Bose corporation

JIT II

ASSIGNMENT• Based on three Supporting Goals and four

Building Blocks of JIT, write about implementation of JIT and Lean System in your organization.

• Minimum – 4 pages

Problem 1,2,3 Page 719 William J. Stevenson

Problem 15.10 Page 627 Jay Heizer, Barry Render, Jagadish Rajasekhar, 9th Edition

Thank You