# 1. jit systems

8/3/2019 # 1. JIT Systems

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Just-in-Time (JIT) Systems

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People Potential

The talents of our people are greatly

underestimated, and their skills are underutilized.Our biggest task is to fundamentally redefine our

relationships with our employees.Jack Welch,

Chairman, General Electric

(From 1981 to 2001)

Message from Tom Peters*

From: Change is the Only Constant

To : Revolution is the Only Constant

Imagination as the Source of Value!

Get and be: Excited/Obsessed/Supercharged!



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A Simple Definition of JIT

A philosophy of manufacturingbased on planned elimination of ALLWASTE,

and improvement of productivity andcustomer value,

throughContinuous Improvement(orKaizen)



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Waste is anything other than the

minimum amount ofequipment,

materials, parts, space, and

workers time, which are

absolutely essential to add value

to the product.

Shoichiro Toyoda

President, Toyota

Introductory Quotation



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Waste in Operations

Examples of Waste



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Examples of Waste



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Traditional View

To meet variations in demand

To smooth out production requirement

To allow flexibility in the production system

To maintain independence of operations To protect against stock outs

To take advantage of low price/quantity discounts

Inventory is good:

Inventory is bad:

Its costly

Inventory exists, in case problems arise



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It is costly

It hides problems

Inventory is evil because:

JIT View

So produce only when needed

Eliminate Inventory



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Inventory Hides ProblemsInventory Hides Problems



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Less Inventory Exposes ProblemsLess Inventory Exposes Problems



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Inventory Hides Problems

PoorQuality

UnreliableSupplier

MachineBreakdownInefficientLayout

BadDesign

LengthySetups



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To Expose Problems:

Reduce Inventory Levels

PoorQuality

UnreliableSupplier

MachineBreakdown

InefficientLayout

BadDesign

LengthySetups



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Remove Sources of Problems and

Repeat the Process

Poor

Quality

UnreliableSupplier

MachineBreakdown

InefficientLayout

BadDesign

LengthySetups



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Push System versus Pull System

Push System (Traditional) (MRP Approach)

Central planning approach determines &disseminates production schedules to all processessimultaneously

An item is released for production at a specified

time, with an associated due date The item moves through a sequence of operations

When one operation is finished, the item is pushed tothe next operation

Finally, the product is pushed to inventory, to meet

forecast demand

Inventory often used as a cushion against lapses incoordination and inventory can be huge.



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Pull System (JIT)

It focuses on the output of the system rather thanthe input

Do not produce more than that can be used / sold

Finished products are pulled from the final

operation in response to firm customer orders This leads to a chain reaction, with each station

pulling material from its preceding station

JIT uses the Kanban system to control the flow of

material with very little work-in-process inventory



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Flow with JIT

Traditional Flow

CustomersSuppliers

Customers

Suppliers

Production Process

(stream of water)

Inventory (stagnant

ponds) Material

(water in

stream)


Streamlined Production



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Traditional FirmPush System (Material Requirements Planning)

Lot arrivals trigger production

WS 1 WS 2 WS 3

MaterialInformation (Production Schedule)

Material is pushed into downstream workstationsregardless of whether resources are available

Excess -Inventory, Equipment, Workers & Overproduction



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Withdrawals trigger production

WS 1 WS 2 WS 3

MaterialInformation (via Kanban/Card)

JIT SystemPull System (Just In Time)

Material is pulled to a workstation just as it isneeded



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Pull System Production Control

Production at Step 2 in controlled by step 3

Production

Step 3

Production

Step 2

Here they come

Production

Step1

Send more widgets Send more widgets

Here they come

Production at Step 1 in controlled by step 2



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How JIT works

FinalAssembly

SubAssembly

SubAssembly

Suppliers

Suppliers

Suppliers

1.1. Production PlannerProduction Planner

gives a schedule togives a schedule to

final assemblyfinal assembly

2.2. Final assembly withdrawsFinal assembly withdraws

part from stations thatpart from stations that

feed it (subassembly)feed it (subassembly)

3.3. Feeding stations thenFeeding stations then

manufacture to replacemanufacture to replace

those withdrawnthose withdrawn

4.4. In order to do so, thoseIn order to do so, those

stations withdraw partsstations withdraw parts

from preceding stationsfrom preceding stations

(suppliers)(suppliers)



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Pull System Production Control



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Producing only

what is needed,

when it is needed

Management philosophy

Continuous & Forced Problem Solving Respect for People

Elimination of Waste

An Integrated Management System

Pull System

Just-in-Time What it is?



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Japanese - Toyota Production System Hewlett Packard - Stockless Production

General Electric - Management by Sight Motorola - Short Cycle Manufacturing

(Based on Time-Based Competition) IBM - Continuous Flow Manufacturing Boeing - Lean Manufacturing

Harley Davidson - MAN (Material as Needed) Westinghouse - MIPS (Minimum Inventory Production System)

RJ Schonberger - World Class Manufacturing

Origins of JIT

Pioneered by Toyota

Adopted by other Japanese manufacturers

Discovered much later by Western World

JIT is also called as



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Attacks waste

Anything not adding value to the product From the customers perspective

Exposes problems & bottlenecks caused by variability

Deviation from optimum

Achieves streamlined production By reducing inventory

Just-in-Time What it does?

JIT Objective: Profit through

Productivity improvement

Cost reduction by eliminating waste: Excessive production resources

Overproduction

Unnecessary capital investment. etc.



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JIT When it Works Best?

Stable Environment Demand is highly stable

Assembly Line production



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People Involvement / Employee

Participation Industrial Engineering Basics

Continuous Improvement

Total Quality Management

Supplier Integration

Just-in-Time What it requires?

What Are Basic Elements of JIT?



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Basic Elements of JIT

Group Technology

Cell Design

5 S Technique

Visual Control Systems

SMED

Quick Changeover



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How Basic Elements of JIT Contribute to the System

Flexible Resources

Facilitates cellular layouts, TPM, and KaizenCellular Layouts

Retain relevant flexibility of job shop, obtain efficiency ofproduction line

Pull (Kanban) Production Control System Produce only what is needed - only when it is needed

Small-Lot Production Faster through-put, greater flexibility

Quick Setups

Facilitates economical small-lot-size productionUniform Production

Create and maintain a stable production system



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Quality at the Source

Facilitates removal of buffers and contributes tostability of the system

Total Productive Maintenance Contributes to stability of the system

Supplier Networks Facilitates frequent, small quantity delivery of materials

How Basic Elements of JIT Contribute to the System



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JIT - A System of Inter-Related Parts

Each of the elements

support and facilitate

many of the

other elements!

If you

implement part of system,

you may get only part

(or less) of the systemspotential benefits



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Suppliers reduced number of suppliers, better relations

supportive supplier relationships, timely qualitydeliveries

shorter lead times

Layout work-cell layouts (group technology based)

movable, changeable, flexible machinery

high level of workplace organization and neatness

reduced space requirements delivery direct to work areas

JIT Contribution to Competitive Advantage



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Inventory

reduced inventory

small lot sizes

low setup times

Scheduling

simplified

zero deviation from

schedules

level schedules

suppliers informed ofschedules

Kanban techniques


Maintenance

scheduled, daily routine

operator involvement

no breakdowns

Quality Production

no scrap, no defects

statistical processcontrol

Improved quality

(design, process,vendor)



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Employee Empowerment Motivated, empowered, cross-trained employees

few job classifications to ensure flexibility ofemployees

training support

Commitment support of management, employees, and

suppliers


Faster response to the customer and higher quality

A Competitive Advantage!



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Benefits of Lean Production

Lower costs

Increased productivity

Greater flexibility

Better relations with suppliers Increased capacity

Better use of human resources

More product variety

Smoother production flows

Worker participation in problem solving

Better vendor relationships

Reduction in indirect labour



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Epilogue



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What I hear I forget, what I see I remember, what Ido I understand Confucius

Modified

What I hear, I forget.

What I hear and see, I remember a little.

What I hear, see and ask questions about or discuss, Ibegin to understand.

When I hear, see, discuss and do, I acquire asknowledge and skill.

What I teach to another, I master.

Anon.



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Thank You!

In nature there are neither rewards nor

punishments; there are only consequences.

Robert B. Ingersoll

Hope:

One of the greatest discoveries a man makes,

one of his great surprises, is to find he can do

what he was afraid he couldnt do

Henry Ford

Warning:

# 1. jit systems

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