SlideShare une entreprise Scribd logo
1  sur  14
LEAN
MANUFACTURING




       BY:

  K. SELVAKUMAR

                  1
Lean Manufacturing How Lean It Is?
                                            By: K. SELVAKUMAR



Lean manufacturing was initially implemented in automobile industries only but later on its
phenomenon success made other industries to go for implementing the same. It covers a wide
variety of operations for reducing waste, increasing productivity and cutting cost. The emphasis in
lean manufacturing is utilization of lesser resources to produce the same goods. Lean system
basically aims at half the hours of engineering effort, half the product development time, half the
investment in machinery, half the hours of human effort in the factory, half the factory space for the
same output, half the defects in the finished product, increased capacity or throughput.

Over the past two decades, lean manufacturing has generated a greater attention and enthusiasm among
the manufacturers, employees and customers. It is not something brand new but is derived from Japanese
Toyota Production System (TPS). The tremendous success of TPS which basically works on waste
reduction made a huge impact allover the world. Lean manufacturing was initially implemented in automobile
industries only but later on its phenomenon success made other industries to go for implementing the same.
It covers a wide variety of operations for reducing waste, increasing productivity and cutting cost. The
emphasis in lean manufacturing is utilization of lesser resources to produce the same goods. Lean system
basically aims at half the hours of engineering effort, half the product development time, half the investment
in machinery, half the hours of human effort in the factory, half the factory space for the same output, half
the defects in the finished product, increased capacity or throughput. Reduced inventories: Raw, W IP (Work
In Progress) and FG (Finished Goods), smaller lot sizes, reduced lead times, improved participation and
morale of employees.

History behind Lean Manufacturing

"Improvement is the hallmark of human being." Down the ages human being aims at improvement and
perfection in all walks of life. It includes health care, working culture, working, technological advancements
and comfort levels etc. The eighteenth century economist Adam Smith suggested that rather than having
one worker make the pin from start to finish, by dividing up the tasks involved in the production of pins and
having a different worker perform each separate task, many more pins could be produced in a day.
Frederick W. Taylor (1911) took a systematic approach to the organization of production by focussing on
making workers' movements more efficient, giving them proper tools to do their jobs and organizing work
within the workspace to maximize the output.

Henry Ford believed that wastage of anything is harmful and should not be encouraged and his famous
quote "we will not so lightly waste material simply because we can reclaim it for salvage involves labour. The
ideal is to have nothing to salvage." signifies this. He was the person who made the difference by developing
movable assembly line, coupled with carefully machined interchangeable parts, brought the price of cars
down from that of a rich person's toy to a tool for transportation that the middle and working classes could
afford. The improvements offered by Adam Smith, Taylor, Ford and other thinkers combined with mass
production being the dominant model U.S. became on of the strongest economies in the world. However,
countries recovered from World W ar-II, adopted new technologies into industries which led to U.S facing stiff
competition in world market.

U.S dominance is decreased during 1970 s and 1980 s in automobiles                  field where as Japan made huge
impact by producing more popular cars with the combination of high                   quality, low price and better fuel
efficiency. Analysis of Japan’s huge success reveals that factors like homogenous   and hardworking nature,
concepts like just-In-Time OIT) and Statistical Process Control (SPC),              organizational changes like Quality
circles and Flexible work categories made the changes possible. Some                 US. companies adopted these
techniques and experienced mixed results.

To understand the exact reason behind Japan’s success, Massachusetts Institute of Technology (MIT)
conducted a study in the late 1980s and compared automobile manufacturers in U.S, Europe and Japan.
The book that was published from this work, "The Machine that Changed the World' (Womack, Jones, and
Roos, 1990), coined and introduced the term "lean manufacturing" to the world. In this book, the authors
argued that manufacturing system as a whole based on maintaining minimal inventories and very high
quality is responsible for Japan’s success rather than one or another parameter like particular cultural factor,


                                                                                                                          2
process improvement or organizational technique. The idea behind coining this lean term is that waste which
can be considered as fat is reduced or made leaner. Table 1 gives the important events that occurred in the
evolution of lean system in a chronological order.
                         Table 1: History behind lean Manufacturing Chronological order




What is Lean Manufacturing?

According to Liker and Wu (2000) lean" is "a philosophy of manufacturing that focuses on delivering the
highest-quality product at the lowest cost and on time." Researchers at the Lean Aerospace Initiative (LA!) at
the Massachusetts Institute of Technology describe lean as "adding value by eliminating waste, being
responsive to change, focusing on quality, and enhancing the effectiveness of the workforce." A
comprehensive understanding of the term lean can be given as: "A team based approach that utilizes
minimum amount of resources, which identifies and eliminates waste (nonvalue-adding activities) through
continuous improvement by following product at the pull of the customer in pursuit of perfection." Lean is
about understanding what is important to the customer, focusing on eliminating waste in any form but not on
elimination of people and expanding capacity by reducing costs and shortening cycle times between order
and ship date

Lean Principles

Lean manufacturing is based on the following five principles.

    1.   Accurately specify the value of the products or services.
    2.   Identify the value stream for each product or service and remove wasted actions.
    3.   Make the product or service value flow without interruptions.
    4.   Let customers pull products or services from the producer.
    5.   Pursue perfection and continuously improve.



                                                                                                                 3
The first principle is defining value to the product. It means what value the product has according to the
customer. Here value is defined as "specific products with specific capabilities offered at specific prices
through a dialogue with specific customers". Once value is decided, the next step is to define value stream.
Value stream is understanding each and every step in the entire process very clearly without any ambiguity.
Here a manufacturer should continually look for unnecessary steps and other forms of waste (muda in
japanese) and reduce or eliminate this waste. The third lean principle is making value flow through the plant.
It means components of the final product should flow smoothly through the plant, going from one station to
other station without a lot of waiting time in between. The traditional approach to this is manufacturing plants
organized by task. The fourth principle is knowing that the customer pulls all activity. In short, this means
that production shouId be tied to demand; no products shouId be built until downstream demand for them
occurs. Fifth principle is the constant pursuit of perfection. Companies will always strive for improving their
efficiencies, cutting costs, and to improve the quality of their products.




Imai’s Golf Analogy

Golf game can be compared with many companies that will give a valuable insight into wastages. In Golf, a
player takes the first hit and moves to a long distance where the ball landed and then takes the next turn. A
player waits for the other players to finish their job before taking his turn. In a four hour golf game, the golf
club is in contact with the ball for less than two seconds only. The same proportion of value-adding to non-
value-adding time prevails in many factories. Analogies include: W aiting for other players = waiting for tools;
Walking = transportation; Selecting a club and addressing the ball = setup. In a factory, the value adding
takes place in a few seconds only. All other time, such as waiting, transportation and setup is non-value-
adding. Lean defines value added as any activity that increases the market form or function of the product or
service. (These are things the customer is willing to pay for.) and non-value added = waste as any activity
that does not add market form or function or is not necessary. (These activities should be eliminated,
simplified, reduced or integrated.) In reality, typically 95% of total lead time is nonvalue added.

Comparison between Batch System and Single Piece Manufacturing System

The comparison between batch and single piece manufacturing system will throw some light on what exactly
this lean manufacturing system is. In batch system flow of material happens in batches. For example, in
figure 2, a batch consists of 5 units whose processing time is 1 minute per unit. This batch has four different
processing steps namely A, B, C and D. All the 5 units, as a batch finish its processing step A, only after 5
minutes. Even though, first unit has come out of the processing step A after one minute, it will wait for the
next processing step B until all the units finish this first processing step. It means only after 5 minutes, all the
goods as a whole (batch) wiII go to the next processing step B. Processing steps B, C and D take 5 minutes
each and in total, only after 20 minutes, the batch will finish all the processing steps.




                                                                                                                       4
Processing time               20 Minutes Total Lead Time for
5 Units
= 1 minute per unit

But when it comes to single piece (unit), the system assumes a different form altogether. Here each unit
once its processing step is finished will move on to the next processing step, without waiting for the other
unit(s) to finish the same processing step. Figure 3 shows a typical single piece manufacturing system. For
example, first unit after finishing its processing step A in 1 minute will subsequently move on to processing
steps B, C and D spending one minute each for all these steps. In total, after 4 minutes, the first unit finishes
all the processing steps. Similarly, second, third, fourth and fifth pieces will finish all these processing steps
after 5, 6, 7 & 8 minutes. This example shows that single piece system takes 8 minutes where as the batch
system takes 20 minutes for the same processing steps. The advantage of single piece system is that
finished pieces whose process is over need not wait until all the pieces finish their processes. This saves a
considerable amount of time and inventory and this system is taken into lean system.




Lean system identifies seven basic wastes or seven deadly sins that a company must reduce or eliminate, if
possible. They are:

    1.   Overproduction
    2.   Inventory
    3.   Transportation
    4.   Defects
    5.   Motion
    6.   Extra Processing
    7.   Waiting

1 . Over-Production

Producing more than what is sold or produce before it is required is over production. It is visible as storage
of material. A product that cannot be sold or has to be dumped at a reduced price becomes a burden and
can be considered as waste. Producing product before the customer needs makes the parts / products to be
stored and ties up money in inventory.


                                                                                                                     5
Causes for Over Production

    • Misuse of automation
    • Just-in-case logic
    • Long process setup
    • Unlevelled scheduling
    • Unbalanced work load
    • Redundant inspections

2. Inventory

This is one of the most frequent types of waste and one of the most expensive to have. It represents the
material between operations due to large lot production or processes with long cycle times.

Causes of Excess Inventory

    • Compensating for inefficiencies and unexpected problems
    • Product complexity
    • Unlevelled scheduling
    • Poor market forecast
    • Unbalanced workload
    • Unreliable shipments by suppliers

3. Transportation

Handling material extra or unnecessarily either to production area or within production areas is
transportation waste. Transportation waste does not add any value to the product instead it increases the
time and energy spent. The right strategy is to minimize or eliminate this waste rather than improving the
transportation.

Causes of Transportation Waste

    • Poor plant layout
    • Poor understanding of the process flow for production
    • Large batch sizes, long lead times, and large storage areas

4. Defects

Occurrence of defects that arise because of manufacturing problems demands correction or re-work which is
a huge amount of waste. It requires additional resources and time to correct defects before shipping or
replace parts that are scrapped due to defects. These defects can be eliminated by error proofing i.e.,
designing the process in such a way that the product is produced one way, which is the correct way, and
every time.

Causes of Defects

    • Little or no process control
    • Poor quality standards or inconsistent quality standards
    • Lack of or little planned equipment preventive maintenance
    • Inadequate education/training/work instructions
    • Product design (Process cannot produce to quality)

5. Motion

Any body movement (motion) that does not add value comes under this type of category. Few of the
examples that come under this category are looking for tools, walking many steps to get parts, more
movements than necessary to perform an operation. Unnecessary or awkward operator motions put undue
stress on the body and cause waste. Improvement in this area will result in increase in productivity, reduced
injury and decrease in workman's compensation claims.



                                                                                                                6
Causes of Motion Waste

    • Poor people/mach ineffectiveness
    • Inconsistent work methods
    • Failure to take ergonomic issues into consideration
    • Poor facility or cell layout
    • Poor workplace organization and housekeeping

6. Extra processing

Doing more processing steps than the customer really requires is unnecessary. Indistinct and unclear
customer requirements cause the manufacturer to add unnecessary processes, which add cost to the
product. Extra processing waste can be minimized by asking questions like why a specific processing step
IS needed and why a specific product is produced.

Causes for Extra Processing Waste

    • Customer true requirements not properly defined
    • Product changes without process changes
    • Over processing to accommodate expected downtime
    • Lack of communication or Extra copies/excessive information
    • Redundant approvals

7. Waiting

Any time that is non-value added where the operator must stop producing good parts and wait for materials
or instructions or equipment downtime is huge loss in manufacturing and come underth is category.

Causes of Wait Time Waste

    • Misuses of automation
    • Unbalanced work load
    • Unplanned maintenance
    • Long process set-up times
    • Upstream quality problems
    • Unleveled scheduling
    • Poor Communication

In addition to these seven wastes, an additional waste category, Under-uti I ized Human Resources is added
into the list because of its importance company.

    8. Under-utilized Human resources

The lack of involvement and participation of the employees in improving operations, quality and safety will
come under this category.

Causes of Under-utilized Human Resources

    • Old thinking, politics and the business culture
    • Poor hiring practices
    • Low or no investment in training
    • Low pay and high turnover strategy
    • Management thinking




                                                                                                              7
Lean Tools

Lean system consists of various tools which are listed in Figure 4




5S

55 is the name of a workplace organization methodology that uses a list of five Japanese words which,
transliterated and translated into English, start with the letter '5'. The components of 5S are listed in Table 2.
It reduces wastes due to clutter, time to find materials and equipment, duplication of equipment, floor space
and inconsistency. It also instills ownership of the process in each employee.




Cellular Manufacturing

Cellular manufacturing, sometimes called cellular or cell production, arranges factory floor labour into semi-
autonomous and multi-skilled teams, or work cells, who manufacture complete products or complex


                                                                                                                     8
components. It produces a family of parts or products on a dedicated line with dedicated operators. Figure 5
shows how a cellular manufacturing system can be. Properly trained and implemented cells are more
flexible and responsive than the traditional mass-production line, and can manage processes, defects,
scheduling, equipment maintenance and other manufacturing issues more efficiently. The main points in
cellular manufacturing are given below.

    • Functional layouts are rearranged into process oriented
    • cells.
    • Machines and workstations are linked.
    • Layouts are designed for efficient flow.
    • All operator requirements are close by.


                                                     Jidoka

                                                     It refers to "automation with human intelligence" (Autonomation).
                                                     Jidoka also refers to the practice of stopping a manual line or
                                                     process when something goes amiss. This type of automation
                                                     implements some supervisory functions rather than production
                                                     functions. Autonomation prevents the production of defective
                                                     products, eliminates overproduction and focuses attention on
                                                     understanding the problem and ensuring that it never recurs. It
                                                     is a quality control process that comprises of the following four
                                                     principles.

                                                          • Detect the abnormality.
                                                          • Stop.
                                                          • Fix or correct the immediate condition.
                                                          • Investigate the root cause and install a countermeasure




Kaizen

The Japanese word “ kaizen” means simply “ improvement “and in management it means, more broadly,
continuous improvement in small increments. This system creates more value with less waste. The
methodology followed is making changes, monitoring results and then adjusting. The term Kaizen Blitz refers
to a team approach to quickly tear down and rebuild a process layout to function more efficiently. The five
main elements of kaizen are:

    • Teamwork
    • Personal discipline
    • Improved morale
    • Quality circles
    • Suggestions for improvement

Poka- Yoke & Mistake Proofing

Poka-yoke is a Japanese term that means "fail-safing" or "mistake-proofing". Any mechanism that helps an
equipment operator avoid (yokeru) mistakes (poka) can be called as Poka-yoke. Its purpose is to eliminate
product defects by preventing, correcting or drawing attention to human errors as they occur. Broadly, the
term also refers to any behaviour-shaping constraint designed into a product to prevent incorrect operation
by the user. It's one of the main components of Shingo's Zero Quality Control (ZQC) system. Three types of
poka-yoke systems for detecting and preventing errors in a mass production system are:

    • The contact method identifies product defects by testing the product's shape, size, color or other
         physical attributes.
    • The fixed-value (or constant number) method alerts the operator if a certain number of movements
         are not made.
    • The motion-step (or sequence) method determines whether the prescribed steps of the process
         have been followed.


                                                                                                                         9
Quick Changeover & SMED

SMED (Single Minute Exchange Die) provides a rapid and efficient way of converting a manufacturing
process from running the current product to running the next product. This rapid changeover is the key to
reducing production lot sizes and thereby improving flow (Mura). The phrase "single minute" does not mean
that all changeovers and start-ups should take only one minute, but they should take less than 10 minutes
(in other words, "single digit minute"). The long-term objective is always zero set-up, in which changeovers
are instantaneous and do not interfere in any way with continuous flow.

Production-Preparation-Process (3P)

Production-Preparation-Process (3P) focuses on eliminating waste through product and process design. 3P
is about rapidly designing product and production processes to ensure capability, built-in quality, productivity
and f1ow-takt-pull. 3P seeks to meet customer requirements by starting with a clean product development
slate to rapidly create and test potential product and process designs that require the least time, material,
and capital resources. It minimizes resources needed such as capital, tooling, space, inventory, and time.
From beginning to end, 3P is an exercise in project management and waste elimination. 3P is a valuable
tool because the cost of eliminating waste in the earliest stages of product development is less than during
the final stages. The typical steps in a 3P are given below.

     • Define product or process design objectives/needs:
     • Flow diagramming
     • Find and analyze examples in nature
     • Sketch and evaluate the process
     • Bui Id, present and select process prototypes
     • Hold design review
     • Develop project implementation plan

Pull manufacturing

In the pull systems, the downstream process takes the product they need and pulls from the producer. The
pull system links accurate information with the process to minimize waiting and overproduction.

Just In Time (JIT)

Just-in-time inventory system focuses on having "the right material, at the right time, at the right place and in
the exact amount", without the safety net of inventory. JIT implementation principles are:

     • Design flow process
     • Total quality control
     • Stabilize schedule
     • Kanban pull system
     • Work with vendors
     • Further reduce inventory in other areas
     • Improve product design

Standard Work

A precise description of each work activity specifying cycle time, talk time, the work sequence of specific
tasks and the minimum inventory of parts on hand needed to conduct the activity.

TaktTime

Takt time can be defined as the maximum time per unit allowed to produce a product in order to meet
demand. It sets the pace for industrial manufacturing lines and becomes the heartbeat of any lean system.

Takt Time can be first determined with the formula:

T = T a /Td



                                                                                                                    10
Where

T= Takt time, e.g. [minutes of work/ unit produced
T, = Net Time available to work, e.g. [Minutes of work/ day] T                   d
                                                                                     = Time demand (customer demand), e.g.
[units required / day]

Theory of Constraints (TOC)

Any manageable system is limited in achieving more of its goal by a very small number of constraints, and
that there is always at least one constraint. TOC is a management philosophy that stresses on removal of
these constraints to increase throughput while decreasing inventory and operating expenses. It primarily
seeks to identify the constraint and restructure the rest of the organization around it, through the use of the
five focusing steps given below.

    • Identify the constraint
    • Decide how to exploit the constraint
    • Subordinate all other processes to above decision
    • Elevate the constraint
    • If, as a result of these steps, the constraint hqs moved, return to Step 1 . Don't let inertia become the
           constraint

Total Productive Maintenance (TPM)

TPM consists of a series of methods that ensures every machine in a production process is always able to
perform its required tasks so that production is never interrupted. In this system, the machine operator
performs much, and sometimes all, of the routine maintenance tasks themselves. This auto-maintenance
brings ownership to the employee. One can think of TPM as "deterioration prevention" and "maintenance
reduction", but not fixing machines.

Training Within Industry (TWI)

TWI provides a systematic approach to sustain changes and continuous improvement by orienting people
into an "improvement" frame of mind, teaching people how to identify opportunities for improving their jobs,
training people how to generate ideas to take advantage of these opportunities and creating ownership for
people to maintain standard work. This is the most underrated operation but brings out revolutionary results.

Value Stream Mapping

It highlights the sources of waste and eliminates them by implementing a future state value stream that can
become reality within a short time. It includes five basic elements that are given below.

    • Identify the target product, product family.
    • Draw current state value stream map, which shows the current steps, delays, and information flows
         required to deliver the target product. This may be a production flow (raw materials to consumer) or
         a design flow (concept to launch).
    • Assess the current state value stream map in terms of creating flow by eliminating waste.
    • Draw future state value stream map.
    • Work towards the future state condition.

Visual Controls

Visual control is a technique employed in many places and contexts whereby control of an activity or
process is made easier or more effective by deliberate use of visual signals. These help everyone involved
can understand the status of the system at a glance. Few of these visual controls are listed below.

    • Colour-coded pipes and wires
    • Indicator lights
    • Painted floor areas for good stock, scrap, trash etc
    • Production status boards
    • Shadow boards for parts and tools
    • Workgroup display boards with charts, metrics, procedures, etc


                                                                                                                             11
Advantages of Lean Manufacturing

     • On-Time delivery
     • Improved response
     • Reduced inventory
     • Improved quality
     • Improved workflow
     • Achievement flexibility
     • Culture change
     • Delegation of accountability
     • Better use of plant
     • Better use of skilled labor
     • Job satisfaction
     • Information Flow


Reasons for Failure of lean Manufacturing System

Some companies report that they have implemented lean manufacturing in their industry but the outcome is
really shocking and there is no improvement at all. The possible reasons for failure could be attributed to the
reasons listed below.

     • The company does not devote enough resources
     • The timeline expectation is too short
     • Lean manufacturing is used to solve every problem
     • Using the name lean but not the principles
     • The expert isn't really an expert
     • The business is beyond repair

The company wants the output only but does not devote and develop enough resources that are very much
required for successful implementation of lean system. Probably this is one of the most important failure
reasons. Without understanding lean system properly, that it requires an overall change, company gives too
short a time frame to see the results. At the same time company wants to solve each and every problem in
the industry with lean techniques only. This also creates many bottle necks, because some problems require
the implementation of some other tools in addition to lean tools only. Company say that they are
implementing lean system but in general they are using the name lean only but not the concepts of lean.
The expert hired for lean implementation may be of substandard and might not fully understand the
implementation procedure which suits company's requirements. Even if all these criteria are met, some
times it may happen that company is beyond repair and improvement may not be possible at all. It means,
it's probably not in need of a lean system but may be in need of re-organization, financial re-capitalization, or
a complete transformation.

Steps for Successful lean Implementation

"It's not necessary to change. Survival is not mandatory." This is the quote given by W. Edwards Deming,
quality guru which tells the entire story behind change and survival. Obviously, companies or organizations
who changes according to the needs only will survive others will perish in the long run. The four key steps
for successful implementation are Prepare and motivate people, Involvement of employee, Information
sharing and identifying and empowering champions.

     • Prepare and Motivate People
         o Widespread orientation to continuous improvement, quality & training
         o Create common understanding of need to change to lean
     • Employee Involvement
         o Push decision making and system development down to the "lowest levels"
         o Trained and truly empowered people
     • Share information and manage expectations
     • Identify & empower champions, particularly operations managers
         o Remove roadblocks (I.e., people, layout, systems)
         o Make it both directive yet empowering

                                                                                                                    12
Performance Measure of lean System

Performance measure Overall Equipment Effectiveness (OEE) system is considered to fit well in a lean
environment. OEE is a hierarchy of metrics which focus on how effectively a manufacturing operation is
utilized. The results are stated in a generic form which allows comparison between manufacturing units in
differing industries. This system consists of six metrics. The hierarchy consists of two top-level measures
and four underlying measures. The two top level metrics, Overall equipment effectiveness (OEE) and Total
Effective Equipment Performance (TEEP) are two closely related measurements that report the overall
utilization of facilities, time and material for manufacturing operations. These top view metrics directly
indicate the gap between actual and ideal performance. Rest of the four underlying metrics provide
understanding as to why and where the OEE and TEEP performance gaps exist.

OEE: It quantifies how well a manufacturing unit performs relative to its designed capacity, during the
periods when it is scheduled to run.

TEEP:Iteasures OEE effectiveness against calendar hours, i.e.: 24 hours per day, 365 days per year.
loading: The portion of the TEEP metric that represents the percentage of total calendar time that is actually
scheduled for operation.

Availability: The portion of the OEE metric represents the percentage of scheduled time that the operation
is available to operate. This is often referred to as Up-time.

Performance: The portion of the OEE metric represents the speed at which the work centre runs as a
percentage of its designed speed.

Quality: The portion of the OEE metric represents the good units produced as a percentage of the total
units started. This is commonly referred to as First Pass Yield.

OEE breaks the performance of a manufacturing unit into three separate but measurable components
namely Availability, Performance, and Quality. Each component points to an aspect of the process that can
be targeted for improvement. OEE may be applied to any individual work centre, or rolled up to department
or plant levels. This tool also allows for drilling down for very specific analysis, such as a particular Part
Number, Shift, or any of several other parameters. It is unlikely that any manufacturing process can run at
100% OEE. Many manufacturers benchmark their industry to set a challenging target, 85% is not
uncommon.

Calculation:

OEE=Availability x Performance x Quality

Availability = Available Time / Scheduled Time

Performance = (Parts Produced * Ideal Cycle Time) / Available Time

Quality = Good Units/ Units Started

loading = Scheduled Time/CalendarTime

TEEP= Loading x GEE

Conclusion

"If we all know we need to improve, the question becomes: why don't we?" This quote gives the logic behind
this paper. Global recession and slowdown has hit all the industries including textile and apparel industries.
At this crucial juncture, all the industries are desperately looking for ways and means to reduce cost,
increase productivity and quality improvement. Japan's most successful Toyota Production System (TPS)
aims at and achieves all these goals in a structured manner. Lean manufacturing system has evolved with
the combined strength of original TPS and other improvements techniques developed over the years. The
goal of lean manufacturing is the aggressive minimization of waste to achieve maximum efficiency of
resources. This paper discusses the history behind lean system, it's objectives and principles, importance of
reduction of non value added activities and ways and means to reduce the same. It also highlights the


                                                                                                                 13
advantages of lean system, reasons behind its failure in implementation and steps for successful
implementation. In a fitting way performance measures of a lean system are elaborated. Reduction or
minimization of waste is called "lean", but achieving desired results is not a cake walk unless one has the
thorough understanding of company, its requirements, bottlenecks in lean implementation and steps for
successful implementation of lean.




References

    • Billesbach, J.T., "Applying Lean Production Principles To A Process Facility," Production and
          Inventory Management Journal, Third Quarter, 1994, PP. 40-44.
    • Dimancescu, D., P. Hines, and N. Rich, The Lean Enterprise, (American Management Association,
          1997).
    • Hines, P., and D. Taylor, Going Lean, Lean Enterprise research center, Cardiff Business School,
          2000.
    • Ohno, 1., Toyota Production System: Beyond large-scale production 1997.
    • Shingo, S., A Study of the Toyota production system from an industrial engineering Viewpoint
          (Cambridge, MA:
    • Productivity Press, 1997).
    • Taylor, S.G., S.M. Seward, and S.F. Bolander," Why The Process Industries are Different,"
          Production and Inventory ManagementJournal, Vol. 22, Fourth Quarter 1981 ,PP. 9-24.
    • Womack, J.P., and D.T Jones, "From Lean Production to the Lean Enterprise," Harvard Business
          Review, March-April 1994, PP. 93-1 03.
    • Womack, J.P., D.T Jones, and D. Ross, The Machine That Changed The World (Macmillan
          Publishing Company, Canada, 1990).
    • Zayko, M., D. Broughman, and W. Hancock, "Lean Manufacturing Yields World Class Improvements
          for small Manufacturer," liE Solutions, Vol. 29, No.4, 1997, PP. 46-64.
    • www.leanenterprise.org.uk
    • www.en.wikipedia.org/wiki/Lean_manufacturing


K. Selvakumar is associated with Pratibha Syntex Private Limited as Technical & Quality Head

Contenu connexe

Tendances

The Toyota Production System - A Transition from Mass Production to Lean Manu...
The Toyota Production System - A Transition from Mass Production to Lean Manu...The Toyota Production System - A Transition from Mass Production to Lean Manu...
The Toyota Production System - A Transition from Mass Production to Lean Manu...Nurhazman Abdul Aziz
 
Toyota production system
Toyota production systemToyota production system
Toyota production systemArya Kulang
 
impact of lean production
impact of lean productionimpact of lean production
impact of lean productionbramyahari
 
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’s
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’sLean and Six Sigma: A Combined Approach for Waste Management in Indian SME’s
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’sIJLT EMAS
 
BASIC OF TOYOTA PRODUCTION SYSTEM
BASIC OF TOYOTA PRODUCTION SYSTEMBASIC OF TOYOTA PRODUCTION SYSTEM
BASIC OF TOYOTA PRODUCTION SYSTEMPrashant thakur
 
Toyota production system-JIT-Lean Operation
Toyota production system-JIT-Lean OperationToyota production system-JIT-Lean Operation
Toyota production system-JIT-Lean OperationShahbaz Jaffri
 
Lean Management explained to CEOs & Others
Lean Management explained to CEOs & OthersLean Management explained to CEOs & Others
Lean Management explained to CEOs & OthersEquable
 
Toyota Production System (broad)
Toyota Production System (broad)Toyota Production System (broad)
Toyota Production System (broad)Aysel Muradlı
 
Toyota Production System
Toyota Production SystemToyota Production System
Toyota Production SystemSIVA PRIYA
 
Toyota production system
Toyota production systemToyota production system
Toyota production systemParitosh Singh
 
Toyota production system
Toyota production systemToyota production system
Toyota production systemAkshay Jain
 

Tendances (20)

Lean manufacturing
Lean manufacturing Lean manufacturing
Lean manufacturing
 
Lean notes
Lean notesLean notes
Lean notes
 
The Toyota Production System - A Transition from Mass Production to Lean Manu...
The Toyota Production System - A Transition from Mass Production to Lean Manu...The Toyota Production System - A Transition from Mass Production to Lean Manu...
The Toyota Production System - A Transition from Mass Production to Lean Manu...
 
Toyota production system
Toyota production systemToyota production system
Toyota production system
 
impact of lean production
impact of lean productionimpact of lean production
impact of lean production
 
Toyota Production System
Toyota Production SystemToyota Production System
Toyota Production System
 
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’s
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’sLean and Six Sigma: A Combined Approach for Waste Management in Indian SME’s
Lean and Six Sigma: A Combined Approach for Waste Management in Indian SME’s
 
Toyota production system
Toyota production systemToyota production system
Toyota production system
 
BASIC OF TOYOTA PRODUCTION SYSTEM
BASIC OF TOYOTA PRODUCTION SYSTEMBASIC OF TOYOTA PRODUCTION SYSTEM
BASIC OF TOYOTA PRODUCTION SYSTEM
 
L1304018086
L1304018086L1304018086
L1304018086
 
Toyota production system-JIT-Lean Operation
Toyota production system-JIT-Lean OperationToyota production system-JIT-Lean Operation
Toyota production system-JIT-Lean Operation
 
10120130405010
1012013040501010120130405010
10120130405010
 
Lean Management explained to CEOs & Others
Lean Management explained to CEOs & OthersLean Management explained to CEOs & Others
Lean Management explained to CEOs & Others
 
toyota production system
toyota production systemtoyota production system
toyota production system
 
Toyota Production System (broad)
Toyota Production System (broad)Toyota Production System (broad)
Toyota Production System (broad)
 
Muhammad Hassan1
Muhammad Hassan1Muhammad Hassan1
Muhammad Hassan1
 
Lean basics
Lean basicsLean basics
Lean basics
 
Toyota Production System
Toyota Production SystemToyota Production System
Toyota Production System
 
Toyota production system
Toyota production systemToyota production system
Toyota production system
 
Toyota production system
Toyota production systemToyota production system
Toyota production system
 

Similaire à Lean Management

Role of IT in Lean Manufacturing: A brief Scenario
Role of IT in Lean Manufacturing: A brief ScenarioRole of IT in Lean Manufacturing: A brief Scenario
Role of IT in Lean Manufacturing: A brief ScenarioIJMER
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...IOSR Journals
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...IOSR Journals
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...IOSR Journals
 
Quality engineering and management
Quality engineering and managementQuality engineering and management
Quality engineering and managementKushal Shah
 
Lean, The And Beverage Industry
Lean, The And Beverage IndustryLean, The And Beverage Industry
Lean, The And Beverage IndustryBrenda Higgins
 
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551Doubravka Vodárková
 
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docx
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docxPROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docx
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docxbfingarjcmc
 
Lean Production And Its Effect On Workplace Health And Safety
Lean Production And Its Effect On Workplace Health And SafetyLean Production And Its Effect On Workplace Health And Safety
Lean Production And Its Effect On Workplace Health And SafetyPeggy Johnson
 
#Guide-Lean_Manufacturing guide teaches ability to transform workplaces
#Guide-Lean_Manufacturing guide teaches ability to transform workplaces#Guide-Lean_Manufacturing guide teaches ability to transform workplaces
#Guide-Lean_Manufacturing guide teaches ability to transform workplacesIslamAbdouAbbas1
 
Lean and agile manufacturing system
Lean and agile manufacturing systemLean and agile manufacturing system
Lean and agile manufacturing systemAnas CK
 

Similaire à Lean Management (18)

Role of IT in Lean Manufacturing: A brief Scenario
Role of IT in Lean Manufacturing: A brief ScenarioRole of IT in Lean Manufacturing: A brief Scenario
Role of IT in Lean Manufacturing: A brief Scenario
 
Lean manufacturing report
Lean manufacturing reportLean manufacturing report
Lean manufacturing report
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
 
J012145256
J012145256J012145256
J012145256
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
 
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
Lean and Agile Manufacturing as productivity enhancement techniques - a compa...
 
Lean manufacturing
Lean manufacturingLean manufacturing
Lean manufacturing
 
Quality engineering and management
Quality engineering and managementQuality engineering and management
Quality engineering and management
 
Lean, The And Beverage Industry
Lean, The And Beverage IndustryLean, The And Beverage Industry
Lean, The And Beverage Industry
 
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551
MIM04_Lean Product Design of Complex Products_Doubravka Vodárková_591551
 
Lean manufacturimg system
Lean manufacturimg systemLean manufacturimg system
Lean manufacturimg system
 
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docx
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docxPROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docx
PROJECT SUBJECT IMPLEMENTATING LEAN MANUFACTURING CONCEPTS WITH EMP.docx
 
Lean Production And Its Effect On Workplace Health And Safety
Lean Production And Its Effect On Workplace Health And SafetyLean Production And Its Effect On Workplace Health And Safety
Lean Production And Its Effect On Workplace Health And Safety
 
#Guide-Lean_Manufacturing guide teaches ability to transform workplaces
#Guide-Lean_Manufacturing guide teaches ability to transform workplaces#Guide-Lean_Manufacturing guide teaches ability to transform workplaces
#Guide-Lean_Manufacturing guide teaches ability to transform workplaces
 
Lean manufacturing
Lean manufacturingLean manufacturing
Lean manufacturing
 
Lean and agile manufacturing system
Lean and agile manufacturing systemLean and agile manufacturing system
Lean and agile manufacturing system
 
Toyota
ToyotaToyota
Toyota
 
Industrial engineer
Industrial engineerIndustrial engineer
Industrial engineer
 

Dernier

Famous Olympic Siblings from the 21st Century
Famous Olympic Siblings from the 21st CenturyFamous Olympic Siblings from the 21st Century
Famous Olympic Siblings from the 21st Centuryrwgiffor
 
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Pune Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service AvailableDipal Arora
 
Insurers' journeys to build a mastery in the IoT usage
Insurers' journeys to build a mastery in the IoT usageInsurers' journeys to build a mastery in the IoT usage
Insurers' journeys to build a mastery in the IoT usageMatteo Carbone
 
John Halpern sued for sexual assault.pdf
John Halpern sued for sexual assault.pdfJohn Halpern sued for sexual assault.pdf
John Halpern sued for sexual assault.pdfAmzadHosen3
 
Pharma Works Profile of Karan Communications
Pharma Works Profile of Karan CommunicationsPharma Works Profile of Karan Communications
Pharma Works Profile of Karan Communicationskarancommunications
 
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...Dave Litwiller
 
The Coffee Bean & Tea Leaf(CBTL), Business strategy case study
The Coffee Bean & Tea Leaf(CBTL), Business strategy case studyThe Coffee Bean & Tea Leaf(CBTL), Business strategy case study
The Coffee Bean & Tea Leaf(CBTL), Business strategy case studyEthan lee
 
Value Proposition canvas- Customer needs and pains
Value Proposition canvas- Customer needs and painsValue Proposition canvas- Customer needs and pains
Value Proposition canvas- Customer needs and painsP&CO
 
Cracking the Cultural Competence Code.pptx
Cracking the Cultural Competence Code.pptxCracking the Cultural Competence Code.pptx
Cracking the Cultural Competence Code.pptxWorkforce Group
 
Monthly Social Media Update April 2024 pptx.pptx
Monthly Social Media Update April 2024 pptx.pptxMonthly Social Media Update April 2024 pptx.pptx
Monthly Social Media Update April 2024 pptx.pptxAndy Lambert
 
7.pdf This presentation captures many uses and the significance of the number...
7.pdf This presentation captures many uses and the significance of the number...7.pdf This presentation captures many uses and the significance of the number...
7.pdf This presentation captures many uses and the significance of the number...Paul Menig
 
HONOR Veterans Event Keynote by Michael Hawkins
HONOR Veterans Event Keynote by Michael HawkinsHONOR Veterans Event Keynote by Michael Hawkins
HONOR Veterans Event Keynote by Michael HawkinsMichael W. Hawkins
 
Mondelez State of Snacking and Future Trends 2023
Mondelez State of Snacking and Future Trends 2023Mondelez State of Snacking and Future Trends 2023
Mondelez State of Snacking and Future Trends 2023Neil Kimberley
 
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRL
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRLMONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRL
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRLSeo
 
Ensure the security of your HCL environment by applying the Zero Trust princi...
Ensure the security of your HCL environment by applying the Zero Trust princi...Ensure the security of your HCL environment by applying the Zero Trust princi...
Ensure the security of your HCL environment by applying the Zero Trust princi...Roland Driesen
 
M.C Lodges -- Guest House in Jhang.
M.C Lodges --  Guest House in Jhang.M.C Lodges --  Guest House in Jhang.
M.C Lodges -- Guest House in Jhang.Aaiza Hassan
 
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...Aggregage
 
Call Girls in Gomti Nagar - 7388211116 - With room Service
Call Girls in Gomti Nagar - 7388211116  - With room ServiceCall Girls in Gomti Nagar - 7388211116  - With room Service
Call Girls in Gomti Nagar - 7388211116 - With room Servicediscovermytutordmt
 
Grateful 7 speech thanking everyone that has helped.pdf
Grateful 7 speech thanking everyone that has helped.pdfGrateful 7 speech thanking everyone that has helped.pdf
Grateful 7 speech thanking everyone that has helped.pdfPaul Menig
 

Dernier (20)

Famous Olympic Siblings from the 21st Century
Famous Olympic Siblings from the 21st CenturyFamous Olympic Siblings from the 21st Century
Famous Olympic Siblings from the 21st Century
 
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service AvailableCall Girls Pune Just Call 9907093804 Top Class Call Girl Service Available
Call Girls Pune Just Call 9907093804 Top Class Call Girl Service Available
 
Insurers' journeys to build a mastery in the IoT usage
Insurers' journeys to build a mastery in the IoT usageInsurers' journeys to build a mastery in the IoT usage
Insurers' journeys to build a mastery in the IoT usage
 
John Halpern sued for sexual assault.pdf
John Halpern sued for sexual assault.pdfJohn Halpern sued for sexual assault.pdf
John Halpern sued for sexual assault.pdf
 
Pharma Works Profile of Karan Communications
Pharma Works Profile of Karan CommunicationsPharma Works Profile of Karan Communications
Pharma Works Profile of Karan Communications
 
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...
Enhancing and Restoring Safety & Quality Cultures - Dave Litwiller - May 2024...
 
The Coffee Bean & Tea Leaf(CBTL), Business strategy case study
The Coffee Bean & Tea Leaf(CBTL), Business strategy case studyThe Coffee Bean & Tea Leaf(CBTL), Business strategy case study
The Coffee Bean & Tea Leaf(CBTL), Business strategy case study
 
Value Proposition canvas- Customer needs and pains
Value Proposition canvas- Customer needs and painsValue Proposition canvas- Customer needs and pains
Value Proposition canvas- Customer needs and pains
 
Cracking the Cultural Competence Code.pptx
Cracking the Cultural Competence Code.pptxCracking the Cultural Competence Code.pptx
Cracking the Cultural Competence Code.pptx
 
Monthly Social Media Update April 2024 pptx.pptx
Monthly Social Media Update April 2024 pptx.pptxMonthly Social Media Update April 2024 pptx.pptx
Monthly Social Media Update April 2024 pptx.pptx
 
7.pdf This presentation captures many uses and the significance of the number...
7.pdf This presentation captures many uses and the significance of the number...7.pdf This presentation captures many uses and the significance of the number...
7.pdf This presentation captures many uses and the significance of the number...
 
Mifty kit IN Salmiya (+918133066128) Abortion pills IN Salmiyah Cytotec pills
Mifty kit IN Salmiya (+918133066128) Abortion pills IN Salmiyah Cytotec pillsMifty kit IN Salmiya (+918133066128) Abortion pills IN Salmiyah Cytotec pills
Mifty kit IN Salmiya (+918133066128) Abortion pills IN Salmiyah Cytotec pills
 
HONOR Veterans Event Keynote by Michael Hawkins
HONOR Veterans Event Keynote by Michael HawkinsHONOR Veterans Event Keynote by Michael Hawkins
HONOR Veterans Event Keynote by Michael Hawkins
 
Mondelez State of Snacking and Future Trends 2023
Mondelez State of Snacking and Future Trends 2023Mondelez State of Snacking and Future Trends 2023
Mondelez State of Snacking and Future Trends 2023
 
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRL
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRLMONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRL
MONA 98765-12871 CALL GIRLS IN LUDHIANA LUDHIANA CALL GIRL
 
Ensure the security of your HCL environment by applying the Zero Trust princi...
Ensure the security of your HCL environment by applying the Zero Trust princi...Ensure the security of your HCL environment by applying the Zero Trust princi...
Ensure the security of your HCL environment by applying the Zero Trust princi...
 
M.C Lodges -- Guest House in Jhang.
M.C Lodges --  Guest House in Jhang.M.C Lodges --  Guest House in Jhang.
M.C Lodges -- Guest House in Jhang.
 
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...
The Path to Product Excellence: Avoiding Common Pitfalls and Enhancing Commun...
 
Call Girls in Gomti Nagar - 7388211116 - With room Service
Call Girls in Gomti Nagar - 7388211116  - With room ServiceCall Girls in Gomti Nagar - 7388211116  - With room Service
Call Girls in Gomti Nagar - 7388211116 - With room Service
 
Grateful 7 speech thanking everyone that has helped.pdf
Grateful 7 speech thanking everyone that has helped.pdfGrateful 7 speech thanking everyone that has helped.pdf
Grateful 7 speech thanking everyone that has helped.pdf
 

Lean Management

  • 1. LEAN MANUFACTURING BY: K. SELVAKUMAR 1
  • 2. Lean Manufacturing How Lean It Is? By: K. SELVAKUMAR Lean manufacturing was initially implemented in automobile industries only but later on its phenomenon success made other industries to go for implementing the same. It covers a wide variety of operations for reducing waste, increasing productivity and cutting cost. The emphasis in lean manufacturing is utilization of lesser resources to produce the same goods. Lean system basically aims at half the hours of engineering effort, half the product development time, half the investment in machinery, half the hours of human effort in the factory, half the factory space for the same output, half the defects in the finished product, increased capacity or throughput. Over the past two decades, lean manufacturing has generated a greater attention and enthusiasm among the manufacturers, employees and customers. It is not something brand new but is derived from Japanese Toyota Production System (TPS). The tremendous success of TPS which basically works on waste reduction made a huge impact allover the world. Lean manufacturing was initially implemented in automobile industries only but later on its phenomenon success made other industries to go for implementing the same. It covers a wide variety of operations for reducing waste, increasing productivity and cutting cost. The emphasis in lean manufacturing is utilization of lesser resources to produce the same goods. Lean system basically aims at half the hours of engineering effort, half the product development time, half the investment in machinery, half the hours of human effort in the factory, half the factory space for the same output, half the defects in the finished product, increased capacity or throughput. Reduced inventories: Raw, W IP (Work In Progress) and FG (Finished Goods), smaller lot sizes, reduced lead times, improved participation and morale of employees. History behind Lean Manufacturing "Improvement is the hallmark of human being." Down the ages human being aims at improvement and perfection in all walks of life. It includes health care, working culture, working, technological advancements and comfort levels etc. The eighteenth century economist Adam Smith suggested that rather than having one worker make the pin from start to finish, by dividing up the tasks involved in the production of pins and having a different worker perform each separate task, many more pins could be produced in a day. Frederick W. Taylor (1911) took a systematic approach to the organization of production by focussing on making workers' movements more efficient, giving them proper tools to do their jobs and organizing work within the workspace to maximize the output. Henry Ford believed that wastage of anything is harmful and should not be encouraged and his famous quote "we will not so lightly waste material simply because we can reclaim it for salvage involves labour. The ideal is to have nothing to salvage." signifies this. He was the person who made the difference by developing movable assembly line, coupled with carefully machined interchangeable parts, brought the price of cars down from that of a rich person's toy to a tool for transportation that the middle and working classes could afford. The improvements offered by Adam Smith, Taylor, Ford and other thinkers combined with mass production being the dominant model U.S. became on of the strongest economies in the world. However, countries recovered from World W ar-II, adopted new technologies into industries which led to U.S facing stiff competition in world market. U.S dominance is decreased during 1970 s and 1980 s in automobiles field where as Japan made huge impact by producing more popular cars with the combination of high quality, low price and better fuel efficiency. Analysis of Japan’s huge success reveals that factors like homogenous and hardworking nature, concepts like just-In-Time OIT) and Statistical Process Control (SPC), organizational changes like Quality circles and Flexible work categories made the changes possible. Some US. companies adopted these techniques and experienced mixed results. To understand the exact reason behind Japan’s success, Massachusetts Institute of Technology (MIT) conducted a study in the late 1980s and compared automobile manufacturers in U.S, Europe and Japan. The book that was published from this work, "The Machine that Changed the World' (Womack, Jones, and Roos, 1990), coined and introduced the term "lean manufacturing" to the world. In this book, the authors argued that manufacturing system as a whole based on maintaining minimal inventories and very high quality is responsible for Japan’s success rather than one or another parameter like particular cultural factor, 2
  • 3. process improvement or organizational technique. The idea behind coining this lean term is that waste which can be considered as fat is reduced or made leaner. Table 1 gives the important events that occurred in the evolution of lean system in a chronological order. Table 1: History behind lean Manufacturing Chronological order What is Lean Manufacturing? According to Liker and Wu (2000) lean" is "a philosophy of manufacturing that focuses on delivering the highest-quality product at the lowest cost and on time." Researchers at the Lean Aerospace Initiative (LA!) at the Massachusetts Institute of Technology describe lean as "adding value by eliminating waste, being responsive to change, focusing on quality, and enhancing the effectiveness of the workforce." A comprehensive understanding of the term lean can be given as: "A team based approach that utilizes minimum amount of resources, which identifies and eliminates waste (nonvalue-adding activities) through continuous improvement by following product at the pull of the customer in pursuit of perfection." Lean is about understanding what is important to the customer, focusing on eliminating waste in any form but not on elimination of people and expanding capacity by reducing costs and shortening cycle times between order and ship date Lean Principles Lean manufacturing is based on the following five principles. 1. Accurately specify the value of the products or services. 2. Identify the value stream for each product or service and remove wasted actions. 3. Make the product or service value flow without interruptions. 4. Let customers pull products or services from the producer. 5. Pursue perfection and continuously improve. 3
  • 4. The first principle is defining value to the product. It means what value the product has according to the customer. Here value is defined as "specific products with specific capabilities offered at specific prices through a dialogue with specific customers". Once value is decided, the next step is to define value stream. Value stream is understanding each and every step in the entire process very clearly without any ambiguity. Here a manufacturer should continually look for unnecessary steps and other forms of waste (muda in japanese) and reduce or eliminate this waste. The third lean principle is making value flow through the plant. It means components of the final product should flow smoothly through the plant, going from one station to other station without a lot of waiting time in between. The traditional approach to this is manufacturing plants organized by task. The fourth principle is knowing that the customer pulls all activity. In short, this means that production shouId be tied to demand; no products shouId be built until downstream demand for them occurs. Fifth principle is the constant pursuit of perfection. Companies will always strive for improving their efficiencies, cutting costs, and to improve the quality of their products. Imai’s Golf Analogy Golf game can be compared with many companies that will give a valuable insight into wastages. In Golf, a player takes the first hit and moves to a long distance where the ball landed and then takes the next turn. A player waits for the other players to finish their job before taking his turn. In a four hour golf game, the golf club is in contact with the ball for less than two seconds only. The same proportion of value-adding to non- value-adding time prevails in many factories. Analogies include: W aiting for other players = waiting for tools; Walking = transportation; Selecting a club and addressing the ball = setup. In a factory, the value adding takes place in a few seconds only. All other time, such as waiting, transportation and setup is non-value- adding. Lean defines value added as any activity that increases the market form or function of the product or service. (These are things the customer is willing to pay for.) and non-value added = waste as any activity that does not add market form or function or is not necessary. (These activities should be eliminated, simplified, reduced or integrated.) In reality, typically 95% of total lead time is nonvalue added. Comparison between Batch System and Single Piece Manufacturing System The comparison between batch and single piece manufacturing system will throw some light on what exactly this lean manufacturing system is. In batch system flow of material happens in batches. For example, in figure 2, a batch consists of 5 units whose processing time is 1 minute per unit. This batch has four different processing steps namely A, B, C and D. All the 5 units, as a batch finish its processing step A, only after 5 minutes. Even though, first unit has come out of the processing step A after one minute, it will wait for the next processing step B until all the units finish this first processing step. It means only after 5 minutes, all the goods as a whole (batch) wiII go to the next processing step B. Processing steps B, C and D take 5 minutes each and in total, only after 20 minutes, the batch will finish all the processing steps. 4
  • 5. Processing time 20 Minutes Total Lead Time for 5 Units = 1 minute per unit But when it comes to single piece (unit), the system assumes a different form altogether. Here each unit once its processing step is finished will move on to the next processing step, without waiting for the other unit(s) to finish the same processing step. Figure 3 shows a typical single piece manufacturing system. For example, first unit after finishing its processing step A in 1 minute will subsequently move on to processing steps B, C and D spending one minute each for all these steps. In total, after 4 minutes, the first unit finishes all the processing steps. Similarly, second, third, fourth and fifth pieces will finish all these processing steps after 5, 6, 7 & 8 minutes. This example shows that single piece system takes 8 minutes where as the batch system takes 20 minutes for the same processing steps. The advantage of single piece system is that finished pieces whose process is over need not wait until all the pieces finish their processes. This saves a considerable amount of time and inventory and this system is taken into lean system. Lean system identifies seven basic wastes or seven deadly sins that a company must reduce or eliminate, if possible. They are: 1. Overproduction 2. Inventory 3. Transportation 4. Defects 5. Motion 6. Extra Processing 7. Waiting 1 . Over-Production Producing more than what is sold or produce before it is required is over production. It is visible as storage of material. A product that cannot be sold or has to be dumped at a reduced price becomes a burden and can be considered as waste. Producing product before the customer needs makes the parts / products to be stored and ties up money in inventory. 5
  • 6. Causes for Over Production • Misuse of automation • Just-in-case logic • Long process setup • Unlevelled scheduling • Unbalanced work load • Redundant inspections 2. Inventory This is one of the most frequent types of waste and one of the most expensive to have. It represents the material between operations due to large lot production or processes with long cycle times. Causes of Excess Inventory • Compensating for inefficiencies and unexpected problems • Product complexity • Unlevelled scheduling • Poor market forecast • Unbalanced workload • Unreliable shipments by suppliers 3. Transportation Handling material extra or unnecessarily either to production area or within production areas is transportation waste. Transportation waste does not add any value to the product instead it increases the time and energy spent. The right strategy is to minimize or eliminate this waste rather than improving the transportation. Causes of Transportation Waste • Poor plant layout • Poor understanding of the process flow for production • Large batch sizes, long lead times, and large storage areas 4. Defects Occurrence of defects that arise because of manufacturing problems demands correction or re-work which is a huge amount of waste. It requires additional resources and time to correct defects before shipping or replace parts that are scrapped due to defects. These defects can be eliminated by error proofing i.e., designing the process in such a way that the product is produced one way, which is the correct way, and every time. Causes of Defects • Little or no process control • Poor quality standards or inconsistent quality standards • Lack of or little planned equipment preventive maintenance • Inadequate education/training/work instructions • Product design (Process cannot produce to quality) 5. Motion Any body movement (motion) that does not add value comes under this type of category. Few of the examples that come under this category are looking for tools, walking many steps to get parts, more movements than necessary to perform an operation. Unnecessary or awkward operator motions put undue stress on the body and cause waste. Improvement in this area will result in increase in productivity, reduced injury and decrease in workman's compensation claims. 6
  • 7. Causes of Motion Waste • Poor people/mach ineffectiveness • Inconsistent work methods • Failure to take ergonomic issues into consideration • Poor facility or cell layout • Poor workplace organization and housekeeping 6. Extra processing Doing more processing steps than the customer really requires is unnecessary. Indistinct and unclear customer requirements cause the manufacturer to add unnecessary processes, which add cost to the product. Extra processing waste can be minimized by asking questions like why a specific processing step IS needed and why a specific product is produced. Causes for Extra Processing Waste • Customer true requirements not properly defined • Product changes without process changes • Over processing to accommodate expected downtime • Lack of communication or Extra copies/excessive information • Redundant approvals 7. Waiting Any time that is non-value added where the operator must stop producing good parts and wait for materials or instructions or equipment downtime is huge loss in manufacturing and come underth is category. Causes of Wait Time Waste • Misuses of automation • Unbalanced work load • Unplanned maintenance • Long process set-up times • Upstream quality problems • Unleveled scheduling • Poor Communication In addition to these seven wastes, an additional waste category, Under-uti I ized Human Resources is added into the list because of its importance company. 8. Under-utilized Human resources The lack of involvement and participation of the employees in improving operations, quality and safety will come under this category. Causes of Under-utilized Human Resources • Old thinking, politics and the business culture • Poor hiring practices • Low or no investment in training • Low pay and high turnover strategy • Management thinking 7
  • 8. Lean Tools Lean system consists of various tools which are listed in Figure 4 5S 55 is the name of a workplace organization methodology that uses a list of five Japanese words which, transliterated and translated into English, start with the letter '5'. The components of 5S are listed in Table 2. It reduces wastes due to clutter, time to find materials and equipment, duplication of equipment, floor space and inconsistency. It also instills ownership of the process in each employee. Cellular Manufacturing Cellular manufacturing, sometimes called cellular or cell production, arranges factory floor labour into semi- autonomous and multi-skilled teams, or work cells, who manufacture complete products or complex 8
  • 9. components. It produces a family of parts or products on a dedicated line with dedicated operators. Figure 5 shows how a cellular manufacturing system can be. Properly trained and implemented cells are more flexible and responsive than the traditional mass-production line, and can manage processes, defects, scheduling, equipment maintenance and other manufacturing issues more efficiently. The main points in cellular manufacturing are given below. • Functional layouts are rearranged into process oriented • cells. • Machines and workstations are linked. • Layouts are designed for efficient flow. • All operator requirements are close by. Jidoka It refers to "automation with human intelligence" (Autonomation). Jidoka also refers to the practice of stopping a manual line or process when something goes amiss. This type of automation implements some supervisory functions rather than production functions. Autonomation prevents the production of defective products, eliminates overproduction and focuses attention on understanding the problem and ensuring that it never recurs. It is a quality control process that comprises of the following four principles. • Detect the abnormality. • Stop. • Fix or correct the immediate condition. • Investigate the root cause and install a countermeasure Kaizen The Japanese word “ kaizen” means simply “ improvement “and in management it means, more broadly, continuous improvement in small increments. This system creates more value with less waste. The methodology followed is making changes, monitoring results and then adjusting. The term Kaizen Blitz refers to a team approach to quickly tear down and rebuild a process layout to function more efficiently. The five main elements of kaizen are: • Teamwork • Personal discipline • Improved morale • Quality circles • Suggestions for improvement Poka- Yoke & Mistake Proofing Poka-yoke is a Japanese term that means "fail-safing" or "mistake-proofing". Any mechanism that helps an equipment operator avoid (yokeru) mistakes (poka) can be called as Poka-yoke. Its purpose is to eliminate product defects by preventing, correcting or drawing attention to human errors as they occur. Broadly, the term also refers to any behaviour-shaping constraint designed into a product to prevent incorrect operation by the user. It's one of the main components of Shingo's Zero Quality Control (ZQC) system. Three types of poka-yoke systems for detecting and preventing errors in a mass production system are: • The contact method identifies product defects by testing the product's shape, size, color or other physical attributes. • The fixed-value (or constant number) method alerts the operator if a certain number of movements are not made. • The motion-step (or sequence) method determines whether the prescribed steps of the process have been followed. 9
  • 10. Quick Changeover & SMED SMED (Single Minute Exchange Die) provides a rapid and efficient way of converting a manufacturing process from running the current product to running the next product. This rapid changeover is the key to reducing production lot sizes and thereby improving flow (Mura). The phrase "single minute" does not mean that all changeovers and start-ups should take only one minute, but they should take less than 10 minutes (in other words, "single digit minute"). The long-term objective is always zero set-up, in which changeovers are instantaneous and do not interfere in any way with continuous flow. Production-Preparation-Process (3P) Production-Preparation-Process (3P) focuses on eliminating waste through product and process design. 3P is about rapidly designing product and production processes to ensure capability, built-in quality, productivity and f1ow-takt-pull. 3P seeks to meet customer requirements by starting with a clean product development slate to rapidly create and test potential product and process designs that require the least time, material, and capital resources. It minimizes resources needed such as capital, tooling, space, inventory, and time. From beginning to end, 3P is an exercise in project management and waste elimination. 3P is a valuable tool because the cost of eliminating waste in the earliest stages of product development is less than during the final stages. The typical steps in a 3P are given below. • Define product or process design objectives/needs: • Flow diagramming • Find and analyze examples in nature • Sketch and evaluate the process • Bui Id, present and select process prototypes • Hold design review • Develop project implementation plan Pull manufacturing In the pull systems, the downstream process takes the product they need and pulls from the producer. The pull system links accurate information with the process to minimize waiting and overproduction. Just In Time (JIT) Just-in-time inventory system focuses on having "the right material, at the right time, at the right place and in the exact amount", without the safety net of inventory. JIT implementation principles are: • Design flow process • Total quality control • Stabilize schedule • Kanban pull system • Work with vendors • Further reduce inventory in other areas • Improve product design Standard Work A precise description of each work activity specifying cycle time, talk time, the work sequence of specific tasks and the minimum inventory of parts on hand needed to conduct the activity. TaktTime Takt time can be defined as the maximum time per unit allowed to produce a product in order to meet demand. It sets the pace for industrial manufacturing lines and becomes the heartbeat of any lean system. Takt Time can be first determined with the formula: T = T a /Td 10
  • 11. Where T= Takt time, e.g. [minutes of work/ unit produced T, = Net Time available to work, e.g. [Minutes of work/ day] T d = Time demand (customer demand), e.g. [units required / day] Theory of Constraints (TOC) Any manageable system is limited in achieving more of its goal by a very small number of constraints, and that there is always at least one constraint. TOC is a management philosophy that stresses on removal of these constraints to increase throughput while decreasing inventory and operating expenses. It primarily seeks to identify the constraint and restructure the rest of the organization around it, through the use of the five focusing steps given below. • Identify the constraint • Decide how to exploit the constraint • Subordinate all other processes to above decision • Elevate the constraint • If, as a result of these steps, the constraint hqs moved, return to Step 1 . Don't let inertia become the constraint Total Productive Maintenance (TPM) TPM consists of a series of methods that ensures every machine in a production process is always able to perform its required tasks so that production is never interrupted. In this system, the machine operator performs much, and sometimes all, of the routine maintenance tasks themselves. This auto-maintenance brings ownership to the employee. One can think of TPM as "deterioration prevention" and "maintenance reduction", but not fixing machines. Training Within Industry (TWI) TWI provides a systematic approach to sustain changes and continuous improvement by orienting people into an "improvement" frame of mind, teaching people how to identify opportunities for improving their jobs, training people how to generate ideas to take advantage of these opportunities and creating ownership for people to maintain standard work. This is the most underrated operation but brings out revolutionary results. Value Stream Mapping It highlights the sources of waste and eliminates them by implementing a future state value stream that can become reality within a short time. It includes five basic elements that are given below. • Identify the target product, product family. • Draw current state value stream map, which shows the current steps, delays, and information flows required to deliver the target product. This may be a production flow (raw materials to consumer) or a design flow (concept to launch). • Assess the current state value stream map in terms of creating flow by eliminating waste. • Draw future state value stream map. • Work towards the future state condition. Visual Controls Visual control is a technique employed in many places and contexts whereby control of an activity or process is made easier or more effective by deliberate use of visual signals. These help everyone involved can understand the status of the system at a glance. Few of these visual controls are listed below. • Colour-coded pipes and wires • Indicator lights • Painted floor areas for good stock, scrap, trash etc • Production status boards • Shadow boards for parts and tools • Workgroup display boards with charts, metrics, procedures, etc 11
  • 12. Advantages of Lean Manufacturing • On-Time delivery • Improved response • Reduced inventory • Improved quality • Improved workflow • Achievement flexibility • Culture change • Delegation of accountability • Better use of plant • Better use of skilled labor • Job satisfaction • Information Flow Reasons for Failure of lean Manufacturing System Some companies report that they have implemented lean manufacturing in their industry but the outcome is really shocking and there is no improvement at all. The possible reasons for failure could be attributed to the reasons listed below. • The company does not devote enough resources • The timeline expectation is too short • Lean manufacturing is used to solve every problem • Using the name lean but not the principles • The expert isn't really an expert • The business is beyond repair The company wants the output only but does not devote and develop enough resources that are very much required for successful implementation of lean system. Probably this is one of the most important failure reasons. Without understanding lean system properly, that it requires an overall change, company gives too short a time frame to see the results. At the same time company wants to solve each and every problem in the industry with lean techniques only. This also creates many bottle necks, because some problems require the implementation of some other tools in addition to lean tools only. Company say that they are implementing lean system but in general they are using the name lean only but not the concepts of lean. The expert hired for lean implementation may be of substandard and might not fully understand the implementation procedure which suits company's requirements. Even if all these criteria are met, some times it may happen that company is beyond repair and improvement may not be possible at all. It means, it's probably not in need of a lean system but may be in need of re-organization, financial re-capitalization, or a complete transformation. Steps for Successful lean Implementation "It's not necessary to change. Survival is not mandatory." This is the quote given by W. Edwards Deming, quality guru which tells the entire story behind change and survival. Obviously, companies or organizations who changes according to the needs only will survive others will perish in the long run. The four key steps for successful implementation are Prepare and motivate people, Involvement of employee, Information sharing and identifying and empowering champions. • Prepare and Motivate People o Widespread orientation to continuous improvement, quality & training o Create common understanding of need to change to lean • Employee Involvement o Push decision making and system development down to the "lowest levels" o Trained and truly empowered people • Share information and manage expectations • Identify & empower champions, particularly operations managers o Remove roadblocks (I.e., people, layout, systems) o Make it both directive yet empowering 12
  • 13. Performance Measure of lean System Performance measure Overall Equipment Effectiveness (OEE) system is considered to fit well in a lean environment. OEE is a hierarchy of metrics which focus on how effectively a manufacturing operation is utilized. The results are stated in a generic form which allows comparison between manufacturing units in differing industries. This system consists of six metrics. The hierarchy consists of two top-level measures and four underlying measures. The two top level metrics, Overall equipment effectiveness (OEE) and Total Effective Equipment Performance (TEEP) are two closely related measurements that report the overall utilization of facilities, time and material for manufacturing operations. These top view metrics directly indicate the gap between actual and ideal performance. Rest of the four underlying metrics provide understanding as to why and where the OEE and TEEP performance gaps exist. OEE: It quantifies how well a manufacturing unit performs relative to its designed capacity, during the periods when it is scheduled to run. TEEP:Iteasures OEE effectiveness against calendar hours, i.e.: 24 hours per day, 365 days per year. loading: The portion of the TEEP metric that represents the percentage of total calendar time that is actually scheduled for operation. Availability: The portion of the OEE metric represents the percentage of scheduled time that the operation is available to operate. This is often referred to as Up-time. Performance: The portion of the OEE metric represents the speed at which the work centre runs as a percentage of its designed speed. Quality: The portion of the OEE metric represents the good units produced as a percentage of the total units started. This is commonly referred to as First Pass Yield. OEE breaks the performance of a manufacturing unit into three separate but measurable components namely Availability, Performance, and Quality. Each component points to an aspect of the process that can be targeted for improvement. OEE may be applied to any individual work centre, or rolled up to department or plant levels. This tool also allows for drilling down for very specific analysis, such as a particular Part Number, Shift, or any of several other parameters. It is unlikely that any manufacturing process can run at 100% OEE. Many manufacturers benchmark their industry to set a challenging target, 85% is not uncommon. Calculation: OEE=Availability x Performance x Quality Availability = Available Time / Scheduled Time Performance = (Parts Produced * Ideal Cycle Time) / Available Time Quality = Good Units/ Units Started loading = Scheduled Time/CalendarTime TEEP= Loading x GEE Conclusion "If we all know we need to improve, the question becomes: why don't we?" This quote gives the logic behind this paper. Global recession and slowdown has hit all the industries including textile and apparel industries. At this crucial juncture, all the industries are desperately looking for ways and means to reduce cost, increase productivity and quality improvement. Japan's most successful Toyota Production System (TPS) aims at and achieves all these goals in a structured manner. Lean manufacturing system has evolved with the combined strength of original TPS and other improvements techniques developed over the years. The goal of lean manufacturing is the aggressive minimization of waste to achieve maximum efficiency of resources. This paper discusses the history behind lean system, it's objectives and principles, importance of reduction of non value added activities and ways and means to reduce the same. It also highlights the 13
  • 14. advantages of lean system, reasons behind its failure in implementation and steps for successful implementation. In a fitting way performance measures of a lean system are elaborated. Reduction or minimization of waste is called "lean", but achieving desired results is not a cake walk unless one has the thorough understanding of company, its requirements, bottlenecks in lean implementation and steps for successful implementation of lean. References • Billesbach, J.T., "Applying Lean Production Principles To A Process Facility," Production and Inventory Management Journal, Third Quarter, 1994, PP. 40-44. • Dimancescu, D., P. Hines, and N. Rich, The Lean Enterprise, (American Management Association, 1997). • Hines, P., and D. Taylor, Going Lean, Lean Enterprise research center, Cardiff Business School, 2000. • Ohno, 1., Toyota Production System: Beyond large-scale production 1997. • Shingo, S., A Study of the Toyota production system from an industrial engineering Viewpoint (Cambridge, MA: • Productivity Press, 1997). • Taylor, S.G., S.M. Seward, and S.F. Bolander," Why The Process Industries are Different," Production and Inventory ManagementJournal, Vol. 22, Fourth Quarter 1981 ,PP. 9-24. • Womack, J.P., and D.T Jones, "From Lean Production to the Lean Enterprise," Harvard Business Review, March-April 1994, PP. 93-1 03. • Womack, J.P., D.T Jones, and D. Ross, The Machine That Changed The World (Macmillan Publishing Company, Canada, 1990). • Zayko, M., D. Broughman, and W. Hancock, "Lean Manufacturing Yields World Class Improvements for small Manufacturer," liE Solutions, Vol. 29, No.4, 1997, PP. 46-64. • www.leanenterprise.org.uk • www.en.wikipedia.org/wiki/Lean_manufacturing K. Selvakumar is associated with Pratibha Syntex Private Limited as Technical & Quality Head