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Lean Manufacturing Tools and TechniquesMs. Maryam FarooqLean ManufacturingA systematic approach to identifying and eliminating waste (non-value-added activities) through continuous improvement by flowing the product at the pull of the customer in pursuit of perfection.Use Lean Manufacturing models to identify wasteful practices, reduce costs, and increase quality.lean means creating more value for customers with fewer resources.

Defining ValueValue Added Activity Any activity that changes the form, fit, or function of materials orinformation to meet customer requirements OR Something customers are willing to pay for

Non-Value-Added Activity All other actions and unwanted features are by definition WASTEadding no value to the customer simply raise costs in our business3TimeValue Added WorkAfterBeforeNon-Value Added WorkTime Eliminate Non-Value-Added Activity3Nancy Anderson: AE has found that for transactional processes approximately 95% of the time spent on a process is waste.

Questions:What if we have necessary steps in our process that do change the form, fit or function but the customer is NOT willing to pay for it? For example, time spent heating a component in the oven

Value Added

Non-Value Added

MachiningStampingAssemblingDesigningCustomer ServiceAnalysisPaintingSealing/WeldingTransportationInventoryDefective materialWait TimeInspectingTestingCorrectingBatchingSetup

7 WastesShigeo Shingo identified 7 main wastes (Muda) common to factoriesTransportation Unnecessary movement of items between processes and inventory Caused, by poor layout and / or process design and planning, unstructured or not understood Value Stream. Inventory Any raw material, Work in Process (WIP) or finished goods which are being stored i.e. no longer having value added to them Caused by overproduction inventory builds up between processes Motion Unnecessary worker movement within a Process Caused by poor workplace layout, poor process planning, poor housekeeping, no Standard Operating Procedures.7 Wastes ContinuedWaiting People or Parts that are waiting for a work cycle to be completed Caused by unreliable Supply Chain, bottlenecks, down time Over-production Production of items sooner or in greater quantities than required for customer demand Often caused by poor planning or incorrect bottleneck assumptionsOver-processing Processing beyond the value required by the Customer Caused by lack of customer focus, Always done it this way attitude, lack of understandingDefects A defect is when the Customer believes they did not get what they paid for.Can have many causes including process variation, customer requirements not understood correctly, mistakesStop @ AbnormalityTakt Time ProductionSingle Piece FlowPull ProductionAutonomationSequencingLevelingTHE HOUSE OF TOYOTA

TPS(Toyota Production System)The house of Toyota is built on two pillars, JIT (Just in Time) and Jidoka, and the foundation of Heijunka.7Heijunka8There are two main elements of HeijunkaLeveling: Overall leveling in the production schedule of the variety and volume of items produced in a given time period. Sequencing: The order in which the parts on the line or in the cell are processed.What is Heijunka ? Heijunka is the process of level loading and sequencing the timing of production.

8What is Jidoka?Automation with a human touch."First used by Sakichi Toyoda at the beginning of the 20th centuryThe word traces its roots to the automatic loom invented by the founder of the Toyota GroupA pillar of the Toyota Production System

JITJIT philosophy means getting the right quantity of goods at the right place and the right timeJIT exceeds the concept of inventory reduction; it is an all-encompassing philosophy geared to eliminate waste, anything that does not add valueTraditional manufacturing systems use push production; JIT uses pull production. Push systems anticipate future demand and produce in advance in order to have products in place when demand occurs. Pull systems work backwards. The last workstation in the production line requests the precise amounts of materials required.

The Key Difference Between Push and PullPush Systems: schedule work releases based on planning.

inherently forecast drivencontrol release rate, observe WIP level

Pull Systems: authorize work releases based on system status (Kanban).

inherently inventory-level drivencontrol WIP level, observe throughput

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Push vs. Pull Mechanics(Exogenous)ScheduleProduction ProcessPUSHPULL(Endogenous)Stock VoidProduction ProcessJobJobPush systems do not limitWIP in the system.Pull systems deliberately establish a limit on WIP.Takt TimeAn important concept in pacing operationsThe heartbeat of a lean systemTakt time = tk (available production time) (rate of customer demand)

Example: Customer demand is eight widgets per day. The plant operates 16 hours per day. Takt time is two hours (16/8 = 2).

One Piece FlowOne-piece flow is the state that exists when products move through a manufacturing process one unit at a time, at a rate determined by the needs of the customerThe opposite of one-piece flow is large-lot productionGoods produced in large lots build delays into the processNo items can move on to the next process until all items in the lot have been processed The larger the lot, the longer the items sit and wait between stepsOne-piece flow is an ideal stateIn daily operation, it is not always possible or desirable to process items just one at a timeThe important thing is to promote continuous flow of products, with the least amount of delay and waiting

KaizenKaizenJapanese wordfor continuous improvement" or "change for the best", refers to philosophy or practices that focus uponcontinuous improvementof processes in manufacturing, engineering, and business management.When used in the business sense and applied to the workplace, kaizen refers to activities that continually improve all functions, and involves all employees from theCEO to theassembly lineworkers.It also applies to processes, such as purchasing andlogistics, that cross organizational boundaries into thesupply chain.It has been applied in healthcare, psychotherapy, life-coaching, government, banking, and other industries.

Andon (Visual Management)A system of flashing lights used to indicate production status in one or more work centers Red - line stoppage Yellow - call for helpGreen - normal operation

16Poka YokePoka Yoke is a Japanese term that means "fail-safing" or "mistake-proofing".The concept was formalized, and the term adopted, by Shigeo Shingo as part of the Toyota Production System.A poka-yoke is any mechanism in a lean manufacturing process that helps an equipment operator avoid (yokeru) mistakes (poka). Its purpose is to eliminate product defects by preventing, correcting, or drawing attention to human errors as they occur.Shingo distinguishes between mistakes (which are inevitable) and defects (which result when a mistake reaches a customer.). The aim of poka yoke is to design devices which prevent mistakes becoming defects.17KanbanKanban literally means visual card, signboard, or billboard.Toyota originally used Kanban cards to limit the amount of inventory tied up in work in progress on a manufacturing floorNot only is excess inventory waste, time spent producing it is time that could be expended elsewhere Kanban cards act as a form of currency representing how WIP Work in Process or in-process inventory) is allowed in a system.18Part DescriptionPart NumberLocation parts will be consumed (customer)Area defining lot size and time allotted for runArea defines when product needs to be rescheduled for productionDefines which equipment product is dedicated to run onDate is hand written by consuming area when pulledWhat tool is used to produce this productTriangular Kanbanfreeleansite.com195S ProgramsSeiri (Sort) This means going through the work area and making sure only essential items are present. This is eliminating tools, materials, fixtures or any other items not used in the process. Everything else is stored or, preferably, discarded.Seiton (Straighten or set in order)Straighten focuses on setting the workplace in order to focus on efficiency. Seison (Sweep or Shine)Keeping the workplace clean as well as neat.Seiketsu (standardize)Standardizing the work practices means operating in a consistent and standardized fashion. Everyone knows their role and exactly what his or her responsibilities areShitsuke (sustain)This means more than just maintaining what has been established. when an issue arises a suggested improvement, a new tool becomes available, or a new output requirement the process is reviewed for improvement. 205S in OfficeBefore 5 S

After 5 S

21TPM = Total Productive Maintenance

Proactive (all employees involved)PreventivePredictivePlannedTotal Productive Maintenance (TPM)Breakdown maintenanceRepairs to make failed machine operationalPreventive maintenanceSystem of periodic inspection and maintenance to keep machines operatingTPM combines preventive maintenance and total quality conceptsQuick setup = Quick changeoverReducing setup cost reducing setup timeSetup reduction time is a prerequisite to lot size reductionSMED (Single Minute Exchange of Dies) methodThe method has been developed by Toyota and then expanded by Dr. Shigeo Shingo (a consultant to Toyota), and has proven its effectiveness in many companies by reducing changeover times (non-value added times) from hours to a less than 10 minutes24Setup Components Internal Setup: consists of setup activities that must be performed while the machine is stopped. External Setup: consists of setup activities that can be carried out while the machine is still operating.It is desirable to:Convert as much internal setup to external setupImprove the setup procedure

25SMED four-step procedureObserve and analyze how the setup is currently performedSeparate internal from external setup activitiesConvert internal to external setup activitiesSimplify and streamline activitiesOverall Equipment EfficiencyOverall Equipment EffectivenessBreak-downsSetup and changeoverIdling and minor stoppagesReduced speedDefects and reworkStarting lossesTo improve the productivity of production equipment, there are three main time losses for equipment based on the value of three activities.27Overall Equipment EfficiencyThe previous grouped losses define three basic indicator.Availability, performance and quality.Overall Equipment Efficiency (OEE) = A P Q

28OEE-Example(Availability)A given Work Center is scheduled to run for an 8-hour (480 minute) shift with a 30-minute scheduled break.Unscheduled downtime = 60 mins Operating Time = (480 30) 60 = 390 mins Availability = *uptime/ **available time Availability 390 minutes / 450 minutes = 86.6%

(*Uptime/Operating time=Scheduled time Unscheduled downtime)**Available time=Total time Scheduled downtime =Scheduled timeOEE-ExampleCont(Performance/Productivity)The Standard Rate for the part being produced is 40 Units/Hour or 1.5 Minutes/UnitThe Work Center produces 242 Total Units during the shift.Time to Produce Parts = 242 Units x 1.5 Minutes/Unit = 363 MinutesPerformance (Productivity) = 363/ 390 = 93.0%

Note: The basis is Total Units, not Good Units. The Performance metric does not penalize for Quality.OEE-ExampleCont(Quality)Total units produced = 242 Defective units = 21Good units = 242 21 = 221

Quality = (Units produced - defective units) / (Units produced) = (242 21 ) / 242 total units produced = 91.32%

Good unitsOEE-ExampleContOEE is calculated with the formula = (Availability)*(Performance)*(Quality)= 86.6% x 93% x 91.32%= 73.55%What Is Cellular Manufacturing?A lean manufacturing approach that helps companies build a variety of products with as little waste as possibleEquipment and workstations arranged in a sequence that supports smooth material flow through the process, with minimal transport or delayDerived from the word CellA Manufacturing Cell consists of people and machines or workstations required for performing the process stepsFor example - if a process for a product requires cutting, followed by drilling and finishing, the cell would include the equipment for performing those steps, arranged in that orderHelps companies achieve two important goals of lean:One-piece flowHigh-variety production

Value Stream Mapping (VSM)Special type of flow chart that uses symbols known as "the language of Lean" to depict and improve the flow of inventory and information. Value Stream Map Symbols Spot weldABCplatingC/T = 30 secC/O = 10 min3 shifts2% scrap rateProcessFinishedgoodsVendorData box3,000 units= 1 dayInventoryPushSupermarket: the location of a predetermined standard inventoryPhysical pullMonandWedShipmentC/T = Cycle TimeC/O = Change over or setup time36Present VSM

Future VSM