By Saurabh Gour

Principles and Practices of Lean Manufacturing

CONTENTS

What is Lean ?

The Lean House

Principles of Lean

Goals of Lean

The 3M’s

Major Wastes (TIMWOODS)

Tools and Techniques of Lean

Practical Implementation

WHAT IS LEAN ??

Lean is a systematic approach for identifying and eliminating waste (non-

value-added activities) through continuous improvement.

Improved flow = Decreased cost

Decreased cost = Sustainable profits

The Lean HouseQUALITY

DELIVERY TIMES COSTSJIT JIDOKA

HEIJUNKA STANDARD WORKING

TAKT TIME

MAN/MACHINE SEPARATION

REDUCTION IN MUDAS KAIZEN

STABILITY

PULL FLOW

(Reduction in all wastages) (Continuous improvements)

(Production leveling)

(Multimachine capabilities)

(Stop & notify anomalies)

(Pace of production to meet demand)

 (Smaller batches, quick response to customer demand

and smooth product flow)

(The seven zeros for zero inventories)

(Customer satisfaction to earn profit)

PILLER-I PILLER-II

(Team stability, method standardization, strategy monitored over time)

Principles of Lean

Specify value from the standpoint of the end customer by product family.

Define value from customer perspective

Identify all the steps in the value stream for each product family, eliminate those steps that do not create value.

Identify the value stream

Make the value-creating steps occur in tight sequence.

Make the process flow

As flow is introduced, let customers pull value from the next upstream activity.

Pull from the customer

Begin the process again and continue it until a state of perfection is reached.

Head towards perfection

To minimize cost,

company must

produce customer demand

only.

Goals of Lean

LEAN GOALS

Improve Quality

Eliminate Waste

Reduce Time

Reduce Total Cost

Company must understand what customer wants & needs to meet his expectations and

requirements.

Reducing the time it takes to finish an activity from start to finish is one of the most

effective ways.

Waste is any activity that consumes

time, resource or space but does not add any value to

the product or service.

3M's: Mura, Muri and Muda

3 M’s

MURA (Unevenness)Any variation leading to unbalanced situations

MUDA (Waste)Any activity in process

that does not add value.

MURI (Overburden)Any activity asking stress or effort from personnel, material or equipment.

The Major Wastes (TIMWOODS) Transportation

Inventory

Motion

Waiting

Over-Production

Over-Processing

Defects

Any movement of material that is not required for “just-in-time” production.

Any supply in excess of one piece flow.

Any movement that does not add value.

Being idle between operations.

Producing more or sooner or faster than needed.

Effort which add no additional customer value to part.

Rework of products to fulfill customer requirements.

The new waste is introduced recently. So, there are total 8 major wastes of lean manufacturing in the useful mnemonic TIMWOODS.

Skills(Unutilized human brains)

Due to not engaging employees, listening to their ideas.

Tools and Techniques of Lean

5s Visual Workplace

Poka-yoke (Error Proofing)

Kanban

Kaizen

Cellular Manufacturing

SMED

OEE

Just-in-time (JIT)

Jidoka

5-S Implementation 5S activity seeks to organize the work place in a way that makes it more

productive.

SEIRI(Clear/sort)

SEITON(Set in order)

SEISO(Shine)

SEIKETSU(Sustain)

SHITSUKE(Discipline)

Remove what is not needed

Place things in such a way that they are easily

accessible

Keep things clean & polished

Standardize the best practices &

process of cleaning

Develop an attitude to follow

above the 4S

The unorganized life without 5s

The systematic life with 5s

Poka-yoke (Error Proofing) Contains fool proofs operations and reduces/eliminates mistakes in

processes.

Helps in minimizing defects before they reach the customer.

Investigation in the defect cause is essential to elimination.

Ex- Color-coding separation, provide fix stoppers.

Kanban Card system that helps control flow & help to establish JIT goals.

Easy to understand and requires a relatively simple setup.

Card should be attached to a product container and contain essential

information (job card and job route card)

Cellular Manufacturing

Work cells are central to the idea of one piece flow.

Equipment is movable and placed in close proximity.

Quick feedback between operators.

Benefits include: Higher throughput, Improved Co-ordination, Improvement

in quality and productivity.

Kaizen means gradual and orderly, continuous improvement.

People work together to make improvements with low capital investments.

Benefits include: Simulation of workers, Save money & time, Create

belongingness.

Kaizen

SMED

Single Minute Exchange of Dies is a “Process” focused on reducing setup

time.

The main objective of SMED is “ Make operator as a surgeon”.

Primary goal is to change all internal setups to external ones.

Reduce length of internal setup if unable to convert to external. Reduce

length of all external setups as well.

Benefits include: Lower manufacturing cost, smaller lot sizes, lower

inventory levels, smoother startups.

OEE Overall Equipment Effectiveness is a measure of the how well lines or

equipment are utilized in relation to their full potential.

OEE

Availability(Measures Down Time Loss)

Performance (Measures Speed Loss)

Quality(Measures Quality Loss)

Set-up loss

Breakdown loss

Minor Stop-pages loss

Speed loss

Start-up loss

In process loss

Inconsistent times, Insufficient skills, Different methods, Poor tooling

Lack of maintenance, Low operator interest, unawareness of problems

Material not available, Change over at start/ end Jams/ overloads

Unclear design specs, Incorrect settings, Poor maintenance history,

Poor machine changeover, Inconsistent materials, No start-up check lists

Inconsistent materials, Process not followed, Gauges not calibrated

OEE = Availability x Performance x Quality

Just-In-Time (JIT) Establish flow processes so there is an even, balanced flow throughout the entire production process. Goal: Generate zero queues & Minimize lot sizes. Benefits include: Reduced inventory levels (improved profits), Improved product quality, Reduced delivery lead times.

It is the ability for machines to be self-dependent and error proof without any human interaction. It contains three elements :

o Separate human from machine worko Machines detect/prevent abnormalitieso “Stop the Line” authority in operation

Jidoka

Practical Implementations in Current Project

OEE: Redesign floor layout and achieved 10% improvement in the overall

productivity by reducing maximum losses.

SMED: Making operator as a surgeon I have achieved quick changeover

in setups at press & CNC Shop.

Single Piece Flow: Reduce Manufacturing lead time 20% by the

elimination of batching concept.

Cell Concept: Establish cell layout for the manufacturing of flexible

jumpers, containing four lines.

Process Redesign: Reduce the production time and eliminate the

unnecessary processes using Time & Motion study.

Thank You