SEMINAR ON QUALITYMANAGEMENTTOPIC:- KANBANPresented by,Majida BJose BenjeminBijo JosephUniversity of Calicut
IntroductionDerived from the combination of two Japanese words, kan ("visual") and ban("card" or "board"), kanban roughly translates to sign board or signal board.In English it has developed a highly specialized meaning - kanban is a process ofmanufacturing or work space organization that relies upon visual signals to controlinventory. Kanban has become synonymous Just in Time production and "demandscheduling. Kanban, as a means of manufacturing, was developed by Toyota during thelate 1940s and early 1950s. During that period, the Toyota Corporation studied Americansupermarkets and their management techniques. Taiichi Ohno, the man credited withdeveloping JIT, saw the relationship between the supermarket and its customer as anefficient means of organizing production, because a supermarket assures future stockwhile only supplying what the consumer has immediately signaled that he or she needs.The premise behind this organization is a visual signal, a kanban. In the case of asupermarket it might be the level in a bin of oranges dipping below a certain marker. Thisvisual signal, in turn, tells the supermarket employee to stock more oranges. Ohno sawthe possibility to deploy this means of organization in Toyotas main machine shop, andhad done so by 1953. In the 1970s, with the economy worsening, kanban made its wayacross the Pacific Ocean to the United States. Since 1977 it has become the principlemeans of implementing Just in Time (JIT) production and is used in all manner of workingenvironments.
Kanban, also spelt kamban, is a Japanese term for “signboard” or “Billboard” that indicates“available capacity (to work)”. Kanban is a concept related to lean and just-in-time (JIT)production. Kanban is a scheduling system that tells you what to produce, when toproduce it, and how much to produce. Between the 1940s and 50s, Taiichi Ohno of Toyotaapplied the Kanban logic in their Toyota Production System (TPS) to support non-centralized “pull” production control. In the post-depression era of 1970s, Kanban waspopularized in the manufacturing industry as a tool for Lean Manufacturing. Of late, manythought-leaders in various industries have found its applicability beyond themanufacturing industry as well. In simplified terms, Kanban is a visual system for managingwork moving through a process - the “value stream”. It is a system for visualizingwork, reducing waste by limiting work in-progress, and maximizing customer value
ContentKanban is a new technique for managing a software development process in a highlyefficient way. Kanban underpins Toyotas "just-in-time" (JIT) production system.Although producing software is a creative activity and therefore different to mass-producing cars, the underlying mechanism for managing the production line can still beapplied.A software development process can be thought of as a pipeline with feature requestsentering one end and improved software emerging from the other end. Inside thepipeline, there will be some kind of process which could range from an informal ad hocprocess to a highly formal phased process. In this article, well assume a simple phasedprocess of: (1) analyse the requirements, (2) develop the code, and (3) test it works.The Effect of BottlenecksA bottleneck in a pipeline restricts flow. The throughput of the pipeline as a whole islimited to the throughput of the bottleneck. Using our development pipeline as anexample: if the testers are only able to test 5 features per week whereas thedevelopers and analysts have the capacity to produce 10 features per week, thethroughput of the pipeline as a whole will only be 5 features per week because thetesters are acting as a bottleneck. If the analysts and developers arent aware that thetesters are the bottleneck, then a backlog of work will begin to pile up in front of thetesters.
The effect is that lead times go up. And, like warehouse stock, work sitting in the pipelineties up investment, creates distance from the market, and drops in value as time goes by.Inevitably, quality suffers. To keep up, the testers start to cut corners. The resulting bugsreleased into production cause problems for the users and waste future pipeline capacity.If, on the other hand, we knew where the bottleneck was, we could redeploy resources tohelp relieve it. For example, the analysts could help with testing and the developers couldwork on test automation. But how do we know where the bottleneck is in any givenprocess? And what happens when it moves?Kanban reveals bottlenecks dynamicallyKanban is incredibly simple, but at the same time incredibly powerful. In its simplestincarnation, a kanban system consists of a big board on the wall with cards or sticky notesplaced in columns with numbers at the top. Limiting work-in-progress reveals thebottlenecks so you can address them. The cards represent work items as they flowthrough the development process represented by the columns. The numbers at the top ofeach column are limits on the number of cards allowed in each column.The limits are the critical difference between a kanban board and any other visualstoryboard. Limiting the amount of work-in-progress (WIP), at each step in theprocess, prevents overproduction and reveals bottlenecks dynamically so that you canaddress them before they get out of hand.
Worked ExampleThe board below shows a situation where the developers and analysts are being preventedfrom taking on any more work until the testers free up a slot and pull in the next work item.At this point the developers and analysts should be looking at ways they can help relievethe burden on the testers.Notice that weve split some of the columns in two, to indicate items being worked on andthose finished and ready to be pulled by the downstream process. There are severaldifferent ways you can layout out the board. This is a fairly simple way. The limits at the topof the split columns cover both the "doing" and "done" columns. Once the testers havefinished testing a feature, they move the card and free up a slot in the "Test" column.
Now the empty slot in the "Test" column can be filled by one of the cards inthe development "done" column. That frees up a slot under "Development"and the next card can be pulled from the "Analysis" column and so on.
A more realistic example would probably involve at least two pallets. The widgetassembler would start working from the second pallet while new stem-bolts were beingmade to refill the first pallet. If this was a high volume widget manufacturingfacility, each widget assembly station might empty a pallet of stem-bolts in just a fewminutes, and there could be 15 or 20 widget assembly stations. Thus there would be acontinual flow of cards going back to the stem-bolt manufacturing area that would causea continual flow of pallets of stem-bolts to be sent to the widget assembly stations.Kanban is Pull (Demand)This is called a "pull" type of production system. The number of stem-bolts that aremade depends on the customer demand--in other words the number of cards receivedby the stem-bolt manufacturing area. Systems other than cards may be used. Forexample, the empty pallets may be returned to the stem-bolt manufacturing area. Eachempty pallet received indicates a need to manufacture 100 more stem-bolts. For othertypes of components, bins, boxes or cages might be used instead of pallets. Orcomponents might be stored on shelves in the widget assembly area. When a shelfbecame empty that signals that more components need to be manufactured and theshelf refilled. In Kanban the method of handling the components is flexible, and dependson the needs of the manufacturing process.
Functions of kanban• Controls the amounts of raw material amounts and of material in Work In Process• Smooth out flow, if sized properly• Tells when and where there is a problem in the process• Assures there is always just enough material on hand to make what is neededTypes of Kanban• Raw Material Kanban – tells suppliers when to send how much of a particular item to aparticular place.• In-Process Kanban – determines the amount of WIP (Work In Process) that can be keptbetween any two operations in a process• Finished Goods Kanban – determines the amount of a product to be kept on hand atany given time. Removal of material from the Finished Goods Kanban acts as a signal formore of that product to be manufactured.Types of Kanban Signals:• A calculated amount of material kept in a designated space, such as a bin or betweenlines on a workbench or on the floor• A card that is used to tell the amount of material to be made or ordered• The markings on a bin that determine when more material needs to be ordered ormade• Any other clear visual signal that indicates it is time to get more material
How Kanbans Work:Material Resupply Kanban:1. All of the parts used to manufacture a particular product are identified as well as thenumber used in each product.2. Lead time is calculated, that is the amount of time it takes for the parts to beordered and delivered.3. The demand for the product over a specific length of time is then determined.4. The number of parts used in the product is multiplied by the number of the productsdemanded over the length of time that it takes to order and receive the parts.5. The goal is to order parts at the point when the number of parts on hand reach theamount that will be used up during the time it takes to order and get the needed partsdelivered. Usually, because of variability in lead time, the amount of reordered partsoccurs is usually a bit more than the amount of parts needed to cover order lead time.Common signals used as kanbans include two bin resupply systems and card systemsKanban has 8 things you need to know. They are broken down into three basicprinciples (how you need to think) and five for properties (what you need to do).
Three Basic PrinciplesStart with what you do nowThe Kanban method does not prescribe a certain setup or procedure. You can overlayKanban properties on top of your existing workflow or process to bring your issues tolight so that you can introduce positive change over time. This makes it very easy tobegin a Kanban implementation as you do not have to make sweeping changes.Agree to pursue incremental, evolutionary changeThe Kanban method is an approach to change management that is designed to meetminimal resistance. Therefore it encourages continuous small incremental andevolutionary changes to your current system. Sweeping changes are discouragedbecause they generally encounter increased resistance due to fear or uncertainty. I callit “baby steps to awesomeness!”Respect the current process, roles, responsibilities & titlesKanban recognizes that there may be value in the existingprocess, roles, responsibilities, & titles. You have existing pieces in they way you dowhat you do that are working properly and worth preserving. Kanban doesn’t prohibitchange, but it doesn’t prescribe it either. If you do make changes, Kanban encouragesincremental change. Incremental change doesn’t create the level of fear that impedesprogress, which allows you to be broader support for your Kanban implementation. Italso makes it easier to implement Kanban. Small course corrections are also justinherently easier than altering the comple
Five Core PropertiesIn his book, Kanban – Successful Evolutionary Change for your Technology Business, DavidAnderson identified five core properties that he consistently observed in successfulimplementations of the Kanban method.Visualize the workflowYou have to understand what it takes to get an item from request to completion. The goalof Kanban is to make positive change to optimize the flow of work through the system.Only after understanding how the workflow currently functions can you aspire to improveit by making the correct adjustments. Making changes before you understand yourworkflow is putting the proverbial cart before the horse and can cause you to makechoices that are, at best, unhelpful and, at worst, harmful.The most common way to visualize your workflow is to use card walls with cards andcolumns. Each column on the wall represents steps in your workflow.Limit WIPLimiting work-in-progress implies that a pull system is implemented on parts or all of theworkflow. The critical elements are that work-in-progress at each state in the workflow islimited and that new work is “pulled” into the next step when there is available capacitywithin the local WIP limit. These constraints will quickly illuminate problem areas in yourflow so you can identify and resolve them. Limiting WIP is the cornerstone of Kanban.
Manage flowThe whole point of implementing a Kanban system is to create positive change. Before youcan create that change you have to know what to change. You figure that out by looking athow things are currently flowing through the system, analyzing problem areas anddefining changes (and, obviously, ultimately implementing them). Then, you repeat thecycle to see what effect your changes had on the system because you need to know if thechange you made had a positive or negative impact on the things you were attempting tochange. You are never finished. To use a cliché, it’s a journey. Something I read recentlysaid that when you fix your first issue, your second one gets a promotion. I think that’s anawesome reminder that we should always strive to make progress.Make Process Policies ExplicitAs I noted in “Visualize your workflow” above, you can’t improve something you don’tunderstand. The process needs to be defined, published and socialized — explicitly andsuccinctly. Without an explicit understanding of how things work and how work is actuallydone, any discussion of problems tends to be emotional, anecdotal and subjective (AKA aknee-jerk reaction). When everyone really understands what you are doing now and whatyour goals are, then you can begin to make decisions regarding change that will move youin a positive direction. The choices will be more rational, empirical, objective discussion ofissues. This is more likely to facilitate consensus around improvement suggestions.
Improve Collaboratively (using models & the scientific method)As discussed, the Kanban method encourages small continuous, incremental andevolutionary changes that stick. When teams have a shared understanding oftheories about work, workflow, process, and risk, they are more likely to be ableto build a shared comprehension of a problem and suggest improvement actionswhich can be agreed by consensus.Benefits of Kanban:Shorter cycle times can deliver features faster.Responsiveness to Change:When priorities change very frequently, Kanban is ideal.Balancing demand against throughput guarantees that most the customer-centricfeatures are always being worked.Requires fewer organization / room set-up changes to get startedReducing waste and removing activities that don’t add value to theteam/department/organizationRapid feedback loops improve the chances of more motivated, empowered andhigher-performing team members
ConclusionAs we have mentioned, establishing a Kanban system in your workplace is very useful in termsof waste reduction and effective utilization of resources. Kan ban is used in material handlingand it is flexible and can be changed according to the situations. Kanban helps to smooth theflow of work to maximize “throughput” and achieve high product quality. Unlike manymethodologies which bring about disruptive changes in an organizations processes, Kanban isan evolutionary system that prefers to gradually improve an organizations current processes.This makes implementing Kanban far easier than other approaches, making it an increasinglypopular tool for managing any type of work, including agile software development.REFERENCEChandra,D,etel,Quality Circles,Tata McGraw Hill,New Delhi 1996.Wakhlu,Bharat,Total Quality,1 ed,Wheeler Publishing, New Delhi,1994http://en.wikipedia.org/wiki/Total quality management.