Lecture 10 JIT

8/13/2019 Lecture 10 JIT

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DELIVERING CUSTOMER

VALUE

Just-in-time (JIT)


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Module Code and Module Title Title of Slides

Supplier Production

Distribution System

Supplier DistributionInventories

Raw material

in-transit

Sub-assembly

parts in-transit

Maintenance,

repair, and ordering

supplies in-transit

Raw Material

Inventory

Work-in-process

InventoryFactory

Finished

Goods

Inventory

Component

Inventory

MRO

Inventory

PurchasingProduction and

Inventory ControlShipping and

Traffic

Retailer

Inventory

Orders

Warehouse

Inventory

Productions Inventories CustomerDistribution

Inventories

Orders


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Management philosophy of continuous

and forced problem solving

Supplies and components are pulledthrough system to arrive wherethey are

needed whenthey are needed.

What is Just-in-Time?


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Attacks waste Anything not adding value to the product

From the customers perspective

Exposes problems and bottleneckscaused by variability Deviation from optimum

Achieves streamlined production By reducing inventory

What Does Just-in-Time Do?


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2001 by Prentice Hall, Inc., Upper Saddle River, N.J. 07458

Overproduction

Waiting

Transportation Inefficient processing

Inventory

Unnecessary motion

Product defects 1995Corel

Corp.

Types of Waste


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8/34Module Code and Module Title Title of Slides

Variability Occurs Because

Employees, machines, and suppliersproduce units that do not conform tostandards, are late, or are not the

proper quantity

Engineering drawings or specificationsare inaccurate

Production personnel try to producebefore drawings or specifications arecomplete

Customer demands are unknown



Push versus Pull

Pushsystem: material is pushedinto

downstream workstations regardless of

whether resources are available

Pullsystem: material is pulledto a

workstation just as it is needed



Suppliers

Preventive

Maintenance

Layout

Inventory

Scheduling

Quality

Employee

Empowerment

JIT

Just-in-TimeSuccess Factors



Incoming material and finished goods

involve waste

Buyer and supplier form JIT partnerships JIT partnerships eliminate

Unnecessary activities

In-plant inventory In-transit inventory

Poor suppliers

Suppliers



Streamlined Production

Flow with JIT

Traditional Flow

CustomersSuppliers

Customers

Suppliers

Production Process(stream of water)

Inventory (stagnantponds) Material

(water instream)



JIT objective: Reduce movement ofpeople and material Movement is waste!

JIT requires Work cells for product families

Moveable or changeable machines

Short distances Little space for inventory

Delivery directly to work areas

Layout



Process Layout Work Cell

Saw

Lathe

Grinder

HeatTreat

Lathe

Lathe

Lathe Saw

HeatTreat

Grinder

Grinder

Press

Press 1

1

2

3

45

2

6

Saw

Press

Work Cell versusProcess Layout



Layout Tactics

Build work cells for families of products

Minimize distance

Design little space for inventory

Improve employee communication

Use poka-yoke devices

Build flexible or movable equipment

Cross train workers to add flexibility



Traditional: inventory exists in case

problems arise

JIT objective: Eliminate inventory

JIT requires Small lot sizes

Low setup time

Containers for fixed number of parts JIT inventory: Minimum inventory to keep

system running

Inventory



JIT Inventory Tactics

Use a pull system to move inventory Reduce lot size

Reduce setup time

Develop Just-in-Timedelivery systemswith suppliers

Deliver directly to point of use

Perform-to-schedule Reduce setup time

Use group technology


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Scrap

Work in process inventory level

(hides problems)

Unreliable

Vendors

Capacity

Imbalances

Lowering InventoryReduces Waste


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Scrap

Reducing inventory reveals

problems so they can be solved.

Unreliable

Vendors

Capacity

Imbalances

WIP

Lowering Inventory

Reduces Waste


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Customer

orders 10

Lot size = 5

Lot 1 Lot 2

Lot size = 2

Lot 1 Lot 2 Lot 3 Lot 4 Lot 5

Reducing Lot Sizes Increases

the Number of Lots


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Involves timing of operations

JIT requires

Communicating schedules to suppliers Level schedules

Freezing part of schedule nearest due date

Small lots

Kanban techniques

Scheduling


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JIT Scheduling Tactics

Communicate the schedule to suppliers Make level schedules

Freeze part of the schedule

Perform to schedule Seek one-piece-make and one-piece-move

Eliminate waste

Produce in small lots Use kanbans

Make each operation produce a perfect part


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

Production quantities evenly distributed

over time (e.g., 7/day)

Build same mix of products everyday

Results in many small lots

Item Monthly Quantity Daily Quantity

A 40 2

B 60 3

Level Schedules


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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 ifsetup times are lowered

Small versus Large Lots

Small lots also increase flexibility to meet

customer demands


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Japanese word for card

Pronounced kahn-bahn (not can-ban)

Authorizes production from downstream

operations Pulls material through plant

May be a card, flag, verbal signal etc.

Used often with fixed-size containers

Add or remove containers to change

production rate

Kanban


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Figure S12.5


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JIT exposes quality problems byreducing inventory

JIT limits number defects with small lots

JIT requires TQM Statistical process control

Worker involvement

Inspect own work

Quality circles

Immediate feedback

Quality


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JIT Quality Tactics

Use statistical process control

Empower employees

Build failsafe methods (poka-yoke,checklists, etc.)

Provide immediate feedback


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Getting employees involved in product

& process improvements Employees know job best!

JIT requires Empowerment

Cross-training

Training support Few job classifications

1995 Corel Corp.

Employee Empowerment


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Module Code and Module Title Title of Slides PowerPoint presentation to accompany Operations


S12-32

Results

Queue and delay reduction, speedsthroughput, frees assets, and wins orders

Quality improvement, reduces waste and

wins orders

Cost reductions, increases margin or

reduces selling price

Variability reductions in the workplace,reduces waste and wins orders

Rework reduction, reduces waste and wins

orders


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Module Code and Module Title Title of Slides PowerPoint presentation to accompany Operations


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Yielding

Faster response to the customer and

higher quality

A competitive advantage!


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Attributes of Lean Producers

use JIT to eliminate virtually all inventory build systems to help employees product a

perfect part every time

reduce space requirements

develop close relationships with suppliers educate suppliers

eliminate all but value-added activities

develop the workforce

make jobs more challenging

reduce the number of job classes and buildworker flexibility

Documents

Lecture 10 JIT