5S METHOD IN LEAN MANUFACTURING

Professor Virgil POPA Ph DMaster degree student Alina BIDIREANU

Master degree student Mihai TOADER„Valahia” University of Targoviste

virgilp51@yahoo.com

AbstractLEAN MANUFACTURING is the production system the produces “more with

less”, being known also as “supple production” or “no loss production”, which means“minimum COSTS production”.

Lean Manufacturing is “thinking and an involvement way for the completeelimination of losses, oriented to the customers’ success, possible to obtain through thesimplification and the permanent improvement of all the processes and the relations in aclimate of mutual trust, respect and full implication of the employees”.

Added value: Any activity that increases the value or the utility of the product orservice requested by the market, namely the activities for which a customer is willing topay.

Loss (Non-added value): Any activity which don’t add value to the product orservice, meaning “what raises the COST of the product without adding VALUE” for thecustomer.

The 5S method include 5 phase:1. SEIRI – Sorting and Filtering

Sorting is a method of freeing de space at the workplace and the elimination of all theunnecessary objects, like programs, test pieces, drawings, old or defective tools,accessories, unused materials, etc. The sorting process has an impact on the mentality atthe workplace and removes the syndrome “it works like this”.

2. SEITON – Stabilization (Systematization of objects location)Stabilization means setting the locations (boundaries). The second step of 5S refers toarranging in order the useful objects at the workplace, so these can be easilyfind/identified and in a logical order to facilitate their use.

3. SEISO – Shining (Shining and cleanliness)Shining means initial cleanliness and the cleanliness of everything represents theworkplace: floor, machines, cabinets, etc. It’s imperative to detect the sources of dirt, thesources of leakage must be corrected and it must be provided enough material to performcleaning at any workplace. This is the only way to improve the products quality and thepeople’s safety.

4. SEIKETSU – StandardizationStandardization means maintaining the status obtained by setting rules, habits andstandard procedures. Standardized work is obtained by finding the best working methodfrom different people, on the same machine or workbench; using the standard equipmentas recipients, various color files, etc.; displaying standard procedures on panels (visualmanagement); using check lists.

5. SHITSUKE – Support for change

Support for change always requires that specific procedures be followed (andstandardized).

Keywords: Lean Manufacturing, 5S, Added value, Loss, Seiri, Seiton, Seiso, Seiketsu,Shitsuke

JEL Classification: L600

IntroductionLEAN MANUFACTURING is the production system the produces “more with

less”, being known also as “supple production” or “no loss production”, which means“minimum COSTS production”. Lean Manufacturing is a production philosophy whichdetermines the reducing of time since the customer order to the product delivery,continuously minimizing the losses. There are many definitions, such:- Lean manufacturing is “a production philosophy that reduces the time elapsed from the

customer order to the product delivery, through reducing the losses (the activities thatdon’t add value to the product)” [J. Womack & D.T. Jones, 1990]

- Lean Manufacturing is “a thinking and an involvement way for the completeelimination of losses, oriented to the customers’ success, possible to obtain throughthe simplification and the permanent improvement of all the processes and therelations in a climate of mutual trust, respect and full implication of the employees” [J.Womack & D.T. Jones, 1996]

Here are few characteristics of the Lean manufacturing: working in continuousflow (cells or flexible assembly lines), poly-qualified workers with a proactive attitude atthe workplace, large diversity of products made in any requested quantity, qualityincorporated in the processes of execution, reduced costs through substantialimprovements in the production process (without complicated systems or largeinvestment), clients and suppliers integrated in the production process.

So, the processes of realization of the products or services requested by thecustomer must be analyzed on the basis of two fundamental concepts:1) Added value: Any activity that increases the value or the utility of the product or

service requested by the market, namely the activities for which a customer is willing topay.

2) Loss (Non-added value): Any activity which don’t add value to the product or service,meaning “what raises the COST of the product without adding VALUE” for thecustomer. These activities must be eliminated, simplified, reduced or integrated.

The Value Stream includes all the component activities of a process, needed forthe realization of the product, from the concept to the launching and from the order to thedelivery. The value stream includes both the activities that processes the informationrelated to the realization of the product, and the actual processing activities of the materialsfor the physical realization of that product. [C. Marchwinski & C. Shook, 2007]

1. Lean Manufacturing

The implementation of the Lean manufacturing process is made for a singleproduct or for a product line of similar products at the same time. It is not recommended todo the Lean change for all product lines and at the same time. The lessons learned from the

first attempt will be the basis for the second attempt and they will simplify the third one,until the lean manufacturing techniques become well known. [J.Wincel, 2004]

The changes made are often similar with the changes from the suppliers. In thedevelopment of the strategy of materials flow, the first discussed element in the leanmedium was the placing of the supplying market. In the implementation of the production,there was introduced and applied concepts as the supply just-in-time and the availability ofthe materials through the kanban system. The purpose of this approach was to eliminate the“push” system of the materials supply and to create a “pull” system. Although the MRPsystem can be a “pull”-type system, it doesn’t reflect so good the consumption needsduring production, like the kanban system. [Y. Monden, 1998]

The following picture reflects a resemblance between the implementation of thelean manufacturing at his beginnings and the SCM steps. A similar comparison can bemade between the materials flow strategy and the continuous improvements.

1. The implementation of Lean ManufacturingLean Manufacturing actions SCM implementation actionsTact time calculation JIT distribution versus Kanban systemDevelopment of standardized work forall operations

“Dock to stock” - elimination of futureinspections

Implementation of the pull systembetween the processes that use kanban

Systematic supply and reviewing thesuppliers’ activityFocus on developing relationships withsuppliers

In a SCM organization, the quality or the development of the activity of one of thesuppliers serve to assist the operational quality in the organization to permanently offeringcorrective actions when the additional assistance in not enough. [J. Wincel, 2004]

2. Seiri, Seiton, Seiso, Seiketsu, Shitsuke – 5S – tool used in LeanManufacturing

2.1. SEIRI – Sorting and Filtering

If you doubt, throw!Sorting is a method of freeing de space at the workplace and the elimination of all

the unnecessary objects, like programs, test pieces, drawings, old or defective tools,accessories, unused materials, etc. The sorting process has an impact on the mentality atthe workplace and removes the syndrome “it works like this”.

The sorting implies the clear differentiation of the elements that are necessaryand must be kept from the elements that aren’t necessary and have to be eliminated.[A. Scotchmer, 2000]

Surprisingly, this concept is misunderstood. In the beginning can be difficult todistinguish between the necessary and the unnecessary elements, therefore in such casesthe recommendation is: “if you doubt, throw”.

People tend to link to the parts having the impression that they will use them on afuture order, and if they see a dismantled machine they think that they will use itsometimes. Meantime, the stocks and the unused machines begin to get in the way of thedaily manufacturing activities. This leads to large losses for the entire plant.

The need of sorting and filtering is determined by the losses recorded by thecompany that result in errors and defects. Between the losses that can be encounter we canenumerate:- useless stocks lead to additional costs of storage;- unnecessary materials require additional spaces in warehouses and on the workplace;- there are used more cabinets and shelving to store unnecessary items;- it is required more manpower to manage the growing stock;- it is increasingly difficult to separate the necessary from the unnecessary stocks because

of their large volume;- the quality of products decreases because of defects that occurs following the stocks

existing on the production line and the equipment failures;- useless stocks and defective equipment requires financial resources to be maintained.

For the easier identification of losses in the sorting is used the strategy of applyingred labels.

The strategy of applying red labelsThe strategy of applying red labels is a method of implementation of the sorting by

marking the useless objects with highly visible red labels.The criterion by which are assigned red labels differs from factory to factory. In

factories stricter in this regard, the period for which these objects are needed relates to theproduction schedule of next week.

Stages of implementation of the strategy: [H. Hirano, 1990]a) Launching of red labeling projects

- Members: employees in production, supply, management and accounting departments.- Period: 1-2 months.- Key element for JIT consultant: the determination of the factory employees to identify

the useless objects.b) Identification of the targets for the application of red labels

- Stocks: raw materials, parts, stocks on the production flow and products.- Equipment: equipment, miscellaneous equipment, tools, transport vehicles, desks, etc.- Location: floor and shelves.

c) Setting the criteria for applying the red labels- It is established the criteria for what is needed and what not.- Example: We will not label the objects that are necessary for the next month production

program, otherwise will be labeled on all other objects.d) Achievement of red labels

- To be easily observed, the red labels should be as large as a standard paper sheet.- For stocks, the labeling teams should write down the name, the quantity, the retain

period and the reason of retain.e) Assignment of red labels

- Related departments staff comes to workshop listen to the description of current statusand are objective in awarding red labels for useless objects.

- The search is made with a critical eye.- The workshop workers won’t be let to decide where to put the red tags. They are too

subjective.- You must act without mercy when assigning the red labels.- If you doubt, assign a red label!- The red labeling must be done intensively for a short period.

f) Assessing targets for the implementation of red labels

- Stocks Dividing the labels into two types: "dead stocks" and "retained stocks". Creation and execution of the program to remove dead stocks; it should include the

quantity, the value, the period. Making a list of useless stocks for easier understanding and to be used in

accounting department.- Equipment

The basic principle: anything stands in the way during the improvement activitieswould be or moved, or removed.

Pursuit of the company's instructions regarding the abandonment procedures ofuseless equipment.

After applying the steps of this strategy you may move from sorting to thestabilization strategy, which uses the information panels.

2.2. SEITON – Stabilization (Systematization of objects location)

Arranging the necessary objects so that everyone can use them easily!Stabilization means setting the locations (boundaries). The second step of 5S refers

to arranging in order the useful objects at the workplace, so these can be easilyfind/identified and in a logical order to facilitate their use. You must establish fixedlocations, like recipients, modular shelves, cabinets with transparent doors, panels,markings on the floor for the access paths, containers or dumpsters for all the usualmaterials and tools, their storage being according the frequency of their utilization. As longas the location is easy to understand for everybody, abnormal situations will be seenimmediately.

Stabilization involves organizing the way how necessary items are kept, sothat anyone can use them easily.

Stabilization always accompanies sorting. Once all is organized and only thenecessary objects remains, their locations are determined.

Generally we could say that the stabilization is actually the standardization.Stabilization in this context, as the basis for standardization, is arranging things so thateveryone can understand where there are held, can use them easily and then return them tothe place from which were taken.

There are three basic requirements for Stabilization: what, where and how much.The signs and labels must clearly display all three elements, so that we can determine whattype of objects is held there, their exact location and the number of objects in that location.

In the stabilization phase there are used many strategies, such as the paintingstrategy, which makes:- Separation lines – mark travel routes within the factory and separate them from the work

areas.- Demarcation lines for the sense of opening doors and corridors marking.- Demarcation lines for the spaces reserved to stocks on the flow.

Stabilization has destinations like:- Warehouses:

FIFO method for stock management – the last stored item is the one given toconsumption.

Efficient use of domestic vehicles – stocks on the production flow must betransported, in this respect is used the promptitude index of transport means which

compares the promptitude of transport means for different types of objects usingvarious storage methods.

Setting storage spaces closer the production line.- Tools and Devices:

Information panels. Color codes.

Knowing the locations of objects (in one sight) lead us to the concept of visualcontrol. An important tool for the stabilization phase is the information panels strategy.

The information panels strategyThis is a method which clearly states where (location), what (object name) and

how much (quantity), is a particular object, as stabilization is achieved.Stages of implementation of the strategy: [H. Hirano, 1990]

a) Determining locations- Deciding the location of objects left behind sorting to be as close to the place of

performance of operations.b) Preparation of the locations

- Organizing the shelves and cabinets.c) Designation of the locations

- Creating and sticking the information plates that clearly indicate where each objectbelongs.

d) Pointing the name of the objects- Creating and sticking the information plates that clearly indicate the name/number of

the shelf or cabinet which will hold the objects.- Indication of the quantities.- Indication of the number of items of stock on each information plate.

e) Transforming the stabilization into a habit.- Transforming the stabilization into a habit so the workplace doesn’t become messy

again.

2.3. SEISO – Shining (Shining and cleanliness)

Everything must be clean and swept!

Shining means initial cleanliness and the cleanliness of everything represents theworkplace: floor, machines, cabinets, etc. It’s imperative to detect the sources of dirt, thesources of leakage must be corrected and it must be provided enough material to performcleaning at any workplace. This is the only way to improve the products quality and thepeople’s safety.

Shining means sweeping the floors and keeping things in order.Shining means inspection, and when we think of cleanliness and brightness we

should imagine someone who has a broom in a hand and a cleaning solution in the other.Phases to achieve the cleanliness and shining: [H. Hirano, 1990]

a) Daily cleaning – Things become clean- Cleaning must become part of daily activities; cleaning and removing the dirt from the

floor, access paths, shelves, cabinets.- Rubbing the surfaces so everything shines.

b) Cleaning inspections – Using the observations

- Once the cleanliness is implemented as daily practice, we can contribute at themaintenance of the conditions by using the practical sense to see defects or otherabnormalities in the various equipment used.

c) Maintaining the cleanliness – Making improvements- As soon as an employee sees a defect, the operator who works on that machine must be

the first who attempt to repair or improve the situation.- If the operator can’t do the repair, it must be called a maintenance technician.- If the operator succeeds to fix the problem, this will be part of his activities for

“inspection of cleanliness”.In the stage of Daily Cleaning the following steps are distinguished:

- Determining the target points to achieve the cleanliness.- Determining the tasks to achieve the cleanliness.- Determining the methods to achieve the cleanliness.- Preparing the tools to achieve the cleanliness.- Implementing the cleaning.

Inspections in achieving the cleanliness involve:- Determining the target points to achieve the cleanliness.- Assigning takes to achieve the cleanliness.- Determining the methods to achieve the cleanliness.- Implementing the inspection.- Implementing the maintenance of the cleanliness.

2.4. SEIKETSU – Standardization

The status resulted from the maintenance of the 3S.

Standardization means maintaining the status obtained by setting rules, habits andstandard procedures. Standardized work is obtained by finding the best working methodfrom different people, on the same machine or workbench; using the standard equipmentas recipients, various color files, etc.; displaying standard procedures on panels (visualmanagement); using check lists.

Standardization assumes that Sorting, Stabilization and Brightness aremaintained.1. Assigning the responsibilities for the 3S

- It is essential to assign to the employees tasks based on the activities they do at theworkplace. It’s imperative to set clear instructions to not create confusion.

2. Integrating the tasks 3S in regular work tasks- If people achieve 3S tasks only when these deviate form their normal course, it is

obvious that 3S system is not enough outlined. These tasks are learned gradually, untilthey became automatisms.

- These can be obtained by visual 5S and 5S maintenance, as parts of current activities.3. Checking the level of maintenance of 3S

- This can be done by using checklists which evaluates the levels of implementing the 3S.For obtaining an impenetrable standardization system there are necessary measures

to:a) Prevent the accumulation of useless objects.b) Prevent the necessity to put things back to specific locations.

2.5. SHITSUKE – Support for change

Creating a habit of maintaining the correct procedures.

Support follows to ensure discipline and commitment of all to keep the obtainedresults. Without the support for change everything can return quickly to a similar situation.For the successful implementation of the 3S method, it is necessary not to startsimultaneously with all the improvements. First it must be developed an environmentwhere the culture of continuous improvement represents the standard. The initiatives mustbe stimulated and rewarded. Time must be allocated for involving in improvement,because this is possible only with the collaboration of all the employees involved in thepilot project implementation.

Support for change always requires that specific procedures be followed (andstandardized).

The management must be committed, should encourage the training actions for theparticipation of the employees in 5S and communicate all the actions and results of the 5Saudit. To do the audit is better to set up audit teams from different departments, whichconduct regular checks (the foreman makes daily checks, head of section makes weekly ormonthly checks and the top management makes quaterly checks).

To realise the Support for change must be used: [H. Hirano, 1990]1. Visual 5S

- There are many things to observe in a factory and anyone maust be capable to do it.2. Correcting the others

- Use positive criticism to make people understand where they was wrong and to acceptthe advices.

3. Lessons to Build the Discipline- Company managers should use their experience to teach the subordinates to make

things better.4. Promotion in the whole company.5. Use of Promotion Tools.

BibliographyWomack J., Jones D.T. (1990) The machine that changed the world, Ross.Womack J., Jones D.T. (1996) Lean Thinking, New York: Simon&Schuster.Marchwinski, C., Shook, J. (2007) Lean Lexicon – a graphical glossary for Lean Thinkers,Third Edition.Wincel, Jeffrey (2004) Lean Supply Chain Management – A handbook for strategicprocurement, Productivity Press.Monden, Yasuhiro (1998) Toyota Production Systems, Productivity Press.Scotchmer, Andrew (2000) 5S Kaizen in 90 minutes, Management Books.Hirano, Hiroyuki (1990) 5 Pillars of the Visual Workplace: The Sourcebook for 5SImplementation, Productivity Press.