lean manufacturing --- an introduction

THE ROAD TO LEAN SENSEI

C.Vishwanathan – Head – Faculty, Chief Mentor and Co-Founder

15 February, 2012

• Lean Manufacturing Explained 1

• Impact of implementing Lean 2

• WIIFY 3

Overview

(c) The School of Continuous Improvement 2011

Origins of Lean

• Henry Ford married batch manufacturing to assembly line manufacturing in 1913.

• Lack of Demand forced Ford to shelve his initiatives.

• Group of Japanese Engineers visit Ford’s factory, and migrate the initiatives to their plant.

• Birth of TPS

• In 1980, James Womack rebundled concepts of TPS to give birth to Lean Manufacturing.


Lean defined

• To eliminate waste and reducing non-value adding activities.

Waste is anything unnecessary

Non-value adding activities are those that don’t add value, or those that the customers are not willing to pay for.


The Lean House


Warusa Kagen

"For the want of a nail the shoe was lost; For the want of a shoe the horse was lost; For the want of a horse the battle was lost; For the failure of battle the kingdom was lost; And all for the want of a horseshoe nail." ((From Gemba Panta Rei))


Warusa Kagen (contd..)

• “Condition of badness” or “How bad things are”

• Represents small abnormalities that are undetected

• Need a keen management eye to identify Warusa Kagen issues.

• The gap between how ideal the process should be and how actually it is performing is bridged.


Warusa Kagen (contd…)

• How to deal with Warusa Kagen?

Demand cleanliness in workplace

Visual Controls

Have respect for people

Adherence to standards and work procedures


Warusa Kagen conditions

• Muda (Waste)

• Mura (Unevenness)

• Muri (Overburden)


3Ms explained

• Muda --- Wasteful work or work that doesn’t add value

• Mura --- Unsteady work, work happening irregularly

• Muri --- Inefficient work.


TIMWOODS

• T – Transportation

• I – Inventory

• M – Motion

• W – Waiting

• O – Over-production

• O – Over-processing

• W – Waiting

• S – Latent Skills


Lean Tools

• The Ideal Modern Organization

• Kanban

• Heijunka

• SMED

• Genchi Gembutsu

• 5S


The Ideal Modern Organization


Lean Tools - Kanban

• Means Signboard

• Is a Scheduling system and not an inventory control system

• Helps determine when to produce, what to produce and how much to produce

• Originated from Toyota in 1953


The Kanban winners

• Focuses on pulling the product than pushing

• Keeps inventory levels low

• Synchronizes demand and production

• Reduces waiting time

When you withdraw units in a system, replace it with a Kanban card illustrating the predecessor to complete X units.


Kanban myths

• Kanban replaces all existing material flow X MRP and Reorder Point (ROP) may still continue.

• Kanban works in all scenarios X Works only in High Volume/Low value components

• Kanban is JIT X Kanban is an integral part of JIT and not JIT by itself


A KANBAN GAME

Heijunka

• Pronounced as Hey-Joonkah

• Production leveling technique used in conjunction with Kanban

• Ensures customer demand is leveled.

• Fixes Mura to a great extent.

(c) The School of Continuous Improvement

2011

A Heijunka Example….


SMED

• Single Minute Exchange of Die

– Fast changeovers

– Reduces Setup Time

– Setups and Changeovers are Downtimes

– Reducing Downtimes improves productivity

Have a dedicated setup team

Special training delivered to reduce setup times.


Genchi Genbutsu

• Go to the Gemba and See.

• Gemba is the place where real work happens, i.e. shop floor and not management cabins

• Problems can be identified by going to the shop-floor and observing only.

• Genchi Genbutsu doesn’t talk about just visit but to Know.

• Correlates to Peters and Waterman’s Management by Wandering.


5S

• A very simple and effective technique used in Leaning Operations.

• Objective is to maintain a clean workplace

• Sort, Straighten, Stabilize, Sweep and Sustain

Takes care of Waste due to Motion


The TIMES in Lean

• TAKT Time

• Cycle Time

• Setup Time

• Lead Time


The TIMES in Lean (contd…)

TAKT Time • The time available for production to meet

customer demand Example --- If a company works for 8 hours, i.e. 480 minutes out of which setup time is 30 minutes and meeting time is 30 minutes and customer needs 100 products, TAKT Time is 420/100 = 4.2 minutes per product.



• TAKT Time sets the pace of production.

• In other words, this is the target for the production line.

In mixed level production scenarios, the TAKT Time should be calculated for individual product lines.



Cycle Time

• The time for which actual work happens on the product/in the process.

• Cycle time = Manual cycle Time + Automatic Cycle Time

• Manual Cycle Time = Work is done manually

• Auto Cycle Time = Work is done by machines



• Cycle Time < TAKT Time = Idle time for resources, and some times Over production

• Cycle Time > TAKT Time = Waiting for customers

• Cycle Time = TAKT Time : Ideal Scenario

If workers work on a product for 2 minutes per unit and machine works for 2 minutes, what is the Cycle Time and explain the impact comparing with TAKT Time of 4.2 minutes per product?



Lead Time

• Time from the order of product to receipt of product by customer

• Also known as Production Lead Time

• Production Lead Time = Wait Time + Cycle Time + Delivery Time


TPM --- For better equipments

• Total Productive Maintenance Better utilization and maintenance of production resources results in improved process capability Unreliable uptime is due to machine breakdowns, which further impacts productivity and flow. Operators and teams of a company are the best to seek and identify the problems in equipment, before they assume damaging proportions.


TPM --- For better equipments (contd…)

• Originated in Japan in 1951, as part of Preventive Maintenance.

• Toyota embraced TPM first as part of TPS in 1960.

• Nippondenso, a part of Toyota, mandated the principle of Autonomous Maintenance due to the high degree of automation in their company.


Goals of TPM

• Zero product Defects

• Zero Equipment Unplanned Failures *

• Zero Accidents

* A scheduled system downtime is not factored by TPM as detrimental.


How to implement TPM

1) Gap analysis on historical product defects/accidents/failures

2) Physical Investigation on equipment (Genchi Genbutsu and Jijutsu)

3) Corrective and incremental actions


8 Pillars of TPM

• Focused improvement (Kobetsu Kaizen)

• Autonomous maintenance (Jishu Hozen)

• Planned Maintenance

• Training and Education

• Early Phase Management

• Quality Maintenance (Hinshitsu Hozen)

• Office TPM

• SHE


OEE, TEEP and TPM

• OEE and TEEP are the key KPIs of TPM

• OEE --- Overall Equipment Effectiveness

• TEEP --- Total Effective Equipment Performance

Both the above metrics show how well facilities in a site are utilized.

(c) The School of Continuous Improvement

2011

OEE, TEEP and TPM (contd…)

• OEE = Availability * Performance * Quality • A P Q

Available = How much time of the total time are the equipment available

Performance = How well do the equipment perform

Quality = What is the defect rate out of the equipment



Availability Calculations

Available production time per day = 480 mins

Scheduled Break Time = 30 mins

Scheduled production time = 450 mins

Scheduled Downtime = 60 mins

Available production time = 390 mins

Availability = 87%



• Performance Calculations Performance = (Products produced*Ideal Cycle Time)/Available Time Number of parts = 100 Time per part = 3 mins Performance = (100 *3)/390 = 77% Performance calculations doesn’t factor quality



• Quality calculations

Quality = Number of good units/Total units

Hypothetically here,

Quality = 90/100 = 90%



OEE = 87% * 77% * 90% = 60.21%

Industry OEE Benchmark is 85%.

Room for improvement.



• TEEP = Loading * OEE

Loading = Scheduled time/Calendar time

Calendar time = 7 days and 24 hours

Scheduled time = 5 days and 24 hours

Loading = 71.4%



TEEP = Loading * OEE

= 71.4% * 60.21%

= 42.98%

Obviously, room for improvement because only 43% of the total effectiveness of your equipment is visible.


Parting words from your Sensei…

• Always respect people. Objective is to implement Lean Manufacturing and not Mean Manufacturing.

• Do Genchi Genbutsu regularly.

• Automation is just a part of the process and not the process itself.


C.Vishwanathan can be reached at

• Facebook = Chandra Vishy

• Linkedin = C Vishwanathan

• Email = [email protected]

• Ph = 8097018079

• Skype = chandrav2


mailto:[email protected]

Any questions??????


lean manufacturing --- an introduction

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