Lean Manufacturing Methods for Process Improvement

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056

Volume: 09 Issue: 12 | Dec 2022 www.irjet.net p-ISSN: 2395-0072

Lean Manufacturing Methods for Process Improvement

Sneha Hariharan1

1Postgraduate Student, College of Engineering Guindy, Anna University, Chennai, Tami, Nadu ***

Abstract - The business environment of today is dynamic, and various businesses are figuring out how to become more skilled and adapt to consumer demands. The necessity for ongoing production process and overall management enhancement is becoming important as a result of the competitiveness's requirement for survival. The study aims to identify wastes in a production process and propose recommendation for improvements. The purpose is also to evaluate the usefulness of various Lean Management tools A singlecasestudy wasselectedastheresearchmethodologyfor the study. The approach of value stream mapping has been used to generate the process's present state. Following the mapping, wastes were analyzed and suggestions for improvement were offered.

Keywords: Value Stream, Lean Tools, Waste, Visual Management, Business

1. INTRODUCTION

For businesses to succeed in today's rapidly expanding industrial sector, maintaining their competitiveness is crucial. Companies must therefore increase their commitment to resource and process optimization if they want to remain as competitive as feasible. Businesses concentrate more on identifying new opportunities and globaltrendsthatenableoptimizationtobemosteffective with fewer resources in order to satisfy client demands. They must concentrate on devising new strategies to withstandthegrowingcompetitivepressurebroughtonby globalization and innovation. Companies must meet or exceed client expectations while maintaining the lowest pricingiftheywanttoremaincompetitiveinthebusiness world.

Companieswithahighlycompetitiveedgearethosethatcan produce products quickly and precisely. The goal is to completetheworkwithperfection,minimizingwaste,and operating accurately in order to meet client demand and deliver the product on schedule. The value stream is a valuabletoolsincespeedisitsessentialcomponent.Given therestrictedsupplyoftime,deliveringsoonergivesyoua significantadvantageoveryourcompetitors.

Oneofthemostpopulartechniquesforcuttingexpensesand wasteisleanmanagement.Itaidsinenhancingproductivity, whichhelpsbusinessessurviveintheincreasinglycutthroat business environment and so aids in their own growth. Knowingthehistoryandkeytraitsofleanmanagementis essential to comprehending its fundamental aspects. Lean

implementationentailsunderstandingthebeststrategiesto utilizegivenaparticularcompany'sfeaturesandhowtodo sointhemostpracticalandstraightforwardwaypossible.

2. LEAN MANUFACURING

2.1 History of Lean

TaiichiOhnohasdefinedtheLeanProductionas:

“All we are doing is looking at the timeline from the movement thecustomergivesusanordertothepointwhenwecollectthe cash. And we are reducing that timeline by removing all the non-value-added wastes.”

Goingbacktothestartofmassmanufacturingiscrucialto comprehendingwhereLeanManagementtechniquescame from. In particular, Henry Ford's American factory introducedthefirstconveyor-styleproductionlinein1913. "Flowproduction,"hegaveitthename.Itwasasignificant advancementfortheentireindustrialworld.HenryFordhad totakecareofalotofthingsbeforehandtogetthere.Allof the products and assemblies of those that would be producedontheconveyorhadtobestandardizedforthat. Additionally, it was crucial to guarantee that product assemblywouldgosmoothlyandbeachievablewithoutthe needforanyadditionalassemblyattheline.Allthetoolsand measurementdeviceshavetobestandardized.Calculating the time, it takes to complete each production step in accordancewiththeregulatedpace.Finally,itwascrucialto teach employees so they could carry out precise and standardizedlabour processes.Theintroduction ofFord's conveyor-lineisregardedasthestartofthehistoryofmass production.

Prior to Ford's introduction of mass production, craft manufacturing practices were the norm. Workers with a varietyofskillswereusedtocreateproductsfromstartto finish.Boththeproductsandthetoolsthatwereemployed lackedanykindofstandardization.Sinceeachproductwas madespecificallyforthecustomer,theproductionprocess tookanunknownamountoftime.

EijiToyota,theCEOofToyotaMotorCompany,paidavisitto theFordmanufacturingfacilityintheUnitedStatesin1950. The goal was to observe the resource use throughout productionandthemanufacturingprocessforthousandsof carsthatwerecomparable.Atthesight,heknewrightaway that it is not possible to make vehicles in Japan with the samelevelofresourcesasinAmerica.

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056

Volume: 09 Issue: 12 | Dec 2022 www.irjet.net p-ISSN: 2395-0072

Japan's economy was in a dire state after being recently decimated by two nuclear bombs. The nation lacked both resources and foreign money. The industries experienced issueswithmaterialsupply,alackoffunding,andascarcity ofpersonnel.Additionally,theJapaneseinternalmarketwas far smaller than the American one. American companies produced thousands of the same goods in a single day, leadingtotheconclusionthatJapanshouldconcentrateon producing much smaller patches. Despite this, Toyota nevertheless chose to adopt the conveyor-line production methodaftermakingminormodificationstoit.Severalnew approacheswereincorporatedwhilesomeofFord'sguiding conceptsweremodified(Kanbansystem,5Setc.).

Toyotahadtomakeconsiderablemodificationsinorderto survive in the cutthroat business industry. Toyota had to concentrate on doing the right thing and only delivering what the consumer desired because they were short on money and resources. It involved picking the appropriate technology and making the appropriate material investments. Producing items that are based on order becamecrucial.Productiondidnotbeginbeforeaconsumer placedanorder.Toyotadividedtheneedsofthecustomers intothreecategoriesinordertoimplementthoseproduction procedures.

1.What(Whatkindofproduct)doesthecustomerwant?

2.Whendoesthecustomerwanttheproduct?

3.Whatquantitydoesthecustomerwant?

Toyotacreateda"pullsystem"todothis,whereproduction onlybeganinresponsetoacustomerrequest.Thevarious stages of the production were regarded as one flow throughouttheentireprocess.Itwasestablishedinsidethe processwhenandhowmuchareneededinordertoensure the best possible utilization and flow of resources. The "ToyotaProductionSystem"isthetermToyotagavetothis newproductionphilosophy.

2.2 Principles of Lean Manufacturing

JonesandWomackhavedefinedLeanProductionasafivestepprocess:

1.Definingcustomervalue-Determiningthevaluethatthe businessprovideswithitsproductsfromtheviewpointof theenduseristhefirststage.

2.Definingthewholevaluestream-Thetasksrequiredto deliverthatvaluemustallbemapped,whichcomessecond. Asitiscrucialtorecognizethestepsintheprocessfromthe start of production to the point at which it reaches the customer.basedonthevalueaddedataspecificpointinthe product'sdevelopment.

3. Making it “Flow” - Thirdly, in order to ensure that the productreachestheconsumerasquicklyaspossibleandat the lowest possible cost, it is crucial to ensure that all operations are running properly along the whole value stream. The value stream's waiting time for the customer should be eliminated or minimized to the greatest extent practicable.

4.“Pulling”fromthecustomerback-Thefourthphaseisto setupapullsystem,inwhichtheproductisconnectedtothe final consumer whose desire initiates manufacturing. In other words, the business should begin producing the requested product as the client requests it. For pull production,themanagementtool“Just-in-time”(JIT)isused toavoidover-production.Themainideaofpullproductionis to reduce unnecessary production and unnecessary inventoriestominimizetheamountofwasteproduction.

5. Striving for “Perfection” - The process of continuous improvementintheprocessofproductionaimstoachieve perfectionintheprocessandtheproduct.Itmeanstodeliver aproducttothecustomersaccordingtohis/herexpectations anddemandswithinthescheduleandwithoutanydefectsor mistakes.Theonlysolutiontoachieveperfectionistohave close communication with customers, managers, and the employeesthatareattachedtotheproductionprocess

2.3 Lean Manufacturing Tools

Leanmanagementtechniquesareimplementedusingawide varietyofeffectiveinstruments.Whatsituationneedstobe analyzeddetermineswhichimplementationmethodshould be used. Therefore, understanding how a certain process functionsasawholeiscrucial.WhilemanyLeanpractices canbeusedalone,many of themare more effective when combined,andhencetheysupportoneanother.It'scritical toestablishtheobjectiveandtherequirementsforsuccess beforeselectingthebeststrategyforimprovement.

2.3.1 Value Stream Mapping

The value stream is the basic building block of lean, so mapping it is the first step in beginning to adopt lean managementintoaproduction.Thepurposeofmappingisto focusonandperceivethebroaderpicture.Itincludesboth value-adding and non-value-adding activities since it includes all the steps necessary to deliver a product. It is crucialtobeginmappingthefullvaluestreamofachosen product in order to make improvements. By mapping the currentstateofaproduction,itispossibletoseeandreview howthevalueflowswithinaprocess.

Term “value stream” refers to all the activities that a companymustdotodesign,order,produceanddeliverthe products or services to a customer. Therefore, there is alwaysavaluestreamwhenthereisaproductbeingmade.

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056

Volume: 09 Issue: 12 | Dec 2022 www.irjet.net p-ISSN: 2395-0072

Thevaluestreamhastwomainflows: 

Theproductionflow,fromtherawmaterialtothe customer. 

Thedesignflow,fromtheconcepttolaunch.

Production flow includes two flows, the information and materialflowthatareequallyimportant.Thetwoflowsare connectedtoeachotherandinordertomakeimprovements it is important to map both of them. As to the production flowisthemovementofmaterialthroughthefactoryandthe informationflowtellseachprocesswhattodonext.

2.3.2 Just – in – Time (JIT)

Oneoftheessentialelementsofleanmanufacturingisthe useofthepullapproach.Thepullstrategyisconsideredto be the most important and fundamental way to improve work flow. Just-in-time (JIT) production is one of the techniques connected to the pull approach in order to producewhatisnecessary, whenitisrequired,andinthe quantitythatisrequired.Withapullsystemthatreactsto actualclientdemand,inventory,materialwaste,andstorage problemsareallreduced.

Itisregardedasthemostadvancedandfrequentlyutilised lean construction technique for eliminating non-valueaddingtasks.Itisfoundedontheideathatwebsiteinventory thatdoesnotprovidevaluetocustomersisviewedaswaste. Itimpliesthattheappropriatetoolsandmaterialsmustbe madeavailableforthemanufacturingasneeded.

2.3.3 Layout

Layout refers to the manner that supplies and tools are organized throughout production. According to Hales (1984), the layout is an arrangement of the operations, machines,andplaces,aswellastherelationshipsthatexist betweenthem.

Thearrangementofmaterialsandequipmentiscrucialfor achieving a successful and effective Lean manufacturing facility.Theoutputwilleventuallybehamperedwhetherthe materialsareproperlypreservedortheplacementsarenot wellthoughtout.

When modifying or upgrading the layout, it is crucial to considerthe positionsand motionsofbothpersonnel and materials.Lesseningthetimespentonthemovesorstorages ofthesemi-finishedgoodsthattakeplacebetweenmachines is one way to do. As a result, they ought to be arranged logicallyorwhereveritispossibletolinkthemtogether.The ideabehindthisisthatamachine'sinputshouldbeclosetoa warehouseforrawmaterialsanditsoutputshouldbeclose to one for finished goods. Additionally, there should be a minimum number of backward movements and transportation path crossings. Every transportation route

consumes precious resources because building space is expensiveandmovingtimeaddsnobenefit.Theidealwould be that there should be as few transportation paths and crossingaspossible.Themaingoalthatthelayouthasinthe Leanproduction,istoincreasetheoverallefficiency.

2.3.4 5S

Thesimplestandmostpopularinstrumentforimplementing leanmanagementisthe5Stechnique.The5Sisasystemthat organises the workplace and encourages the culture of continuous improvement. "A place for everything and everything in its place" is the guiding principle of the 5S technique. The process of creating a clean, efficient, and productive workplace is utilized to minimize waste and increaseproductivity.

Thefivephasesof5Sincludeanoverviewoftheworkplace's objects, the removal of anything unnecessary, arranging them,cleaning,conductingmaintenance,andensuringthat theaforementionedactionsbecomehabits.Byimplementing 5S, the workplace becomes more organized, making it simplertospotissuesandimprovingmaterialflow.The5S togethercreateacontinuousprocessforimprovingthework environment.

The5Sare:

Seiri(Sort)

Seiton(Setinorder)

Seiso(Shine)

Seiketsu(Standardize)

Shitsuke(Sustain)

Sortistheinitialphaseintheprocess,wheretheobjectiveis tocleartheworkspaceorroomofanysuperfluousmaterials so that the spaces can then be arranged. Additionally, it suggestsacleanslateonwhichtoconstructandcarryout thenextfourprocesses.Everythingthatisunnecessarywill betakenoutofthetargetareaatthebeginningoftheSort process. Even if it merely involves moving stuff from one location to another and piling useless items on top of one other. Choosing between objects that are still needed or utilizedandthosethatarenolongerneededorusedismade easierbydoingthis.

The second step of the 5S process, "Set in Order," concentrates on returning the products that were determinedtobevitalintheSortparttotheworkspaces,but in a precise and well-organized manner. Finding the most practical and effective locations for those goods in that region is the aim of this stage. This phase can be put into practice in a workspace using a variety of methods and strategies.

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056

Volume: 09 Issue: 12 | Dec 2022 www.irjet.net p-ISSN: 2395-0072

Shine,thethirdstage,isintendedtocleanorsanitize.This processinvolvesthoroughcleaningoftheentireworkplace. Workerssweep,vacuum,dust,andpolishtheentirearea.An organized workstation equates to a secure one. The likelihoodoftripping,slipping,andfallingwillbedecreased if the floors are clean. Additionally, when workplaces are tidy and clean, there is less risk of contracting various diseases or other health risks. These cleanings are to be carriedoutoftenandaccordingtoaschedule.

Thefourthphaseofthe5Sprocessis"Standardize,"where the tips that were encountered in step one is directly applied.Theconceptofregularlyinspectingandreviewing the5Sactivitieswillbedevelopedinthislevel.Itfunctionsas alinkbetweenthe"Shine"andthefifth5Sstage.Therefore, by standardizing the 5S method, it helps to assure that organizationaleffortswillbesustainedoverthelongterm. Poorstandardizationcancausethetasktobecomesloppy overtime,whichwillreduceitsefficiency.Itiscriticaltogo beyond an oral agreement in order to standardize 5S processes.Allpartiesmustbecertainofwhateachpersonis required to perform through a clear, understandable approach.Implementing5Saudits,wherethereisalistthat mustbecoveredandcheckedonaregularbasis,isoneway todothis.Specificquestionsaboutthespecifiedworkarea shouldbeincludedonthechecklisttohelpensurethatthe procedureiscarriedoutasintended.Makingguidelinesis crucial in this step since everyone needs to know exactly howandwhenaspecificactivityistobecompleted.

The final and most challenging phase of the 5S process is "Sustain,"whichfocusesonturningalloftheprecedingsteps into continuing routines to assure their continuous improvement.

In order to get the most benefits out of this step it is importanttofollowfoursteps:



Demonstration–everythingthatisrequiredfrom theworkersshouldbedemonstratedcorrectlybya person who has the right skills, training and knowledge. Thus, workers will gain the understandingofwhatisactuallyneededfromthem todo.

mighthavevariousconsequencesthusleadtofaulty systems.

Overall,the5Sapproachisanelementofleanmanagement and is used to reduce waste in order to increase quality standards.Itismostfrequentlyutilisedbecauseitdoesn't demandsignificantinvestmentfrombusinesses,whichwill increaseproductivity.Thestrategyhastheaddedbenefitof increasing the workers' excitement and punctuality throughout the procedure, creating a safer working environment.

2.3.5 Heijunka

LevelingisthemeaningoftheJapanesewordheijunka.Itisa leanapproachtoloweringthepossibilityofoverburdenand reducingvarianceorunevennessintheproductionprocess. It aids in managing fluctuations in consumer demand and makingthemostuseofavailablemanpowerandresources. Heijunkaimplementationassistsintransitioningfrombatch productiontoproductioninresponsetocustomerdemand, which lowers inventory costs associated with retaining resources and goods while demand is low. Even when demand is great, Heijunka is required to complete the processorflowofworkatatakt-time.Takt-time“istheunit oftimewithinwhichaproductmustbeproduced(Supply rate)tomatchtherateatwhichitisrequired(Demandrate).

2.3.6 Kanban

Theword"sign"or"visualsign"istranslatedas"kanban"in Japanese.Inthewest,itiscommonlyreferredtoasa"card," which indicates that something needs to be delivered or produced.Avisiblegoalandanunseengoalarebothpartof theKanbansystem.

TheovertgoalofKanbanistoprovideamethodtocontrol productionbetweenprocesses,resultingintheproductionof onlywhatisrequiredandwhenitisrequired.

The system's hidden goal is to facilitate process improvementbyestablishingthedesirablesystemiclinkages between processes, hence revealing areas that require improvement.EventhoughKanbanhastwoobjectives,they areinterdependent.



Supervisedundertakings–forworkertoknowwhat is expected they need to work with closely. Monitoringworkersthroughtheveryfirststepsin ordertoensurethatthedailyused5Smethodsare beingformedintoexpectedandde-siredhabits.



Periodic check-ins – regularly checking if those techniquesthatwereobtainedinthestandardizing steparerunningsmoothly.

Kanban aids in maintaining control over product and component stockpiles as well as inventory levels. In rare circumstances, it can also be applied to the most effective management of raw material inventories. By utilizing the Kanbansystem,itispossibletomanageproductandstock levels such that they are constantly present in the productionunit.Additionally,itverifiesthattherearen'ttoo manyofthoseitemsormaterialspresent.



Makechangesasnecessary –havingacontinuous undesired behaviours and un-desired result that

Thismethodofschedulinghasthebenefitofeliminatingthe daily scheduling tasks required to run the production

International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056

Volume: 09 Issue: 12 | Dec 2022 www.irjet.net p-ISSN: 2395-0072

operations.Additionally,thestrategyeliminatestheneedfor ongoingschedulestatusandchangeovertimemonitoring.

The flow of materials or pieces during manufacturing is triggeredorcontrolledbytheKanbansystemusingcardsas avisualindicator,synchronizingbothinternalorganizational activitiesandexternalsupplier-relatedprocedures.

The movement of components and materials across productionprocessesisgovernedbycardsthatareutilized asaKanbansystem.Theproductionlineismovedusingthe same material the entire time. The card serves as a work order,sowhenmoresuppliesorpartsarerequired,itsends thenecessaryKanbantothesupplier.

Typically,aKanbancardcontainsthefollowinginformation abouttheproductionofitems:

•Whattoproduce

•Howtoproduceit

•Whentoproduceit

•Howmuchtoproduce

•Howtotransportit

•Wheretostoreit

Production and withdrawal Kanban cards are the two varieties now in use. a creation Kanban is a term used to definethequantityofanitemthatmustbeproduced.When the Kanban card is held in the hand, production of that particular item begins. To retrieve objects from earlier processes or storages, the second type is employed. The Kanbancardmustbeaffixedtotheactualitemsothatitcan travelwiththem.

3. CONCLUSIONS

Thepurposeofthisstudywastoidentifythecategoriesof waste in the chosen manufacturing process using fundamental Lean Management principles, analyze the causes of their occurrence, and offer solutions to prevent them.Thisiscrucialsince,inordertocompeteeffectively, production processes and productivity must always be improved.

By limiting tasks that do not boost profitability, lean management aims to maximise the cost- and timeeffectiveness of each process. Maximizing customer value creationwhilereducingwasteisLean'skeyobjective.Simply defined,thegoalistoincreasecustomervaluewhileusing the least number of resources. a business that adheres to lean concepts, comprehends how to add value for clients, andconcentratesoncrucialprocedures

REFERENCES

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