JIT Scheduling, KANBAN, JIT Services
Przemyslaw Nawrot, Louis SchmidtJIT Scheduling Schedules have to be communicated inside and outside of a companyInventory is low Reduction of workOrdering big amount makes your costs lower
Lower Setup costs Lower Total costs
fluent way of producing -> lower setup costs and plummeting odering and holding costs
JIT exists only when a supplier and purchaserwork together
prefer small batches than a large batch
Jelly bean scheduling
exactly schedule can improve performance improve performance and you only produce what your demand is!KANBANJapanese word = Card
authorization for next container of materialsmall lot sizes move inventory only as neededrather than pushing it whether the next workstation is ready for it or not
Different sorts of signals are used, but the system is still called Kanban (CARD)cardsflagsempty positions on the floor
important = authorization of the card pulled from the producing department/ supplier
KANBAN - no visual contact / visual contact
signal markerPart numbersmark collection
no visual contactvisual contactcardselectronic signals (computer, lights, internet)
empty positions on the floorflags
move when its needed = PULL-SYSTEM
arrivals in work center to match processing timereduce inventory pull only when needed
how kanban works, pulling units as needed from production.e.g. similar to the resupply that occurs in your neighborhood supermarket
customer buysstock clerk observes the shelf or receives notice from the end-of-day sales list and restockslimited supply in the stores storage is depleted, a pull signal is sent to the warehouse, distributor, or manufacturer for resupply, usually that night.the complicating factor in a manufacturing firm is the time needed for the actual manufacturing to take place.Kanban - more informationeach card = responsible specific parts or quantitypossible that a multiple card system is usedKanban system limit on the amount of work-in-process between cellsKanban doesnt has to be FORMAL.Example of KANBAN + JIT(fast-food restaurant)KANBAN:
6 cars in line informal kanban signal is5 will order french fries and 3 Big Mac chef should start cooking
Cooking french fries and BigMacs in a JIT - way!
Example of JIT McD's
Number of Kanban Containersinformation needed:lead time to produce a container of partsamount of safety stock needed
Number of KanbansDaily demandProduction lead time(Wait time + Material handling time + Processing time)Safety stockContainer size= 500 cakes= 2 daysaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa= day demand= 250 cakes Demand during lead time = 2 days x 500 cakes = 1.000
Number of Kanbans = (1.000 + 250)/250 = 5Advantages of KanbanReduced amount of faulty or delayed materialproblems are immediately evidentPuts downward pressure on bad aspects of inventorystandardized containers reduce weight, disposal costs, wasted space + laborKanban final statement MRP system JIT schedule as a build authorization and the kanban as a type of pull system that initiatives the actual production
JIT in services JIT techniques used in services: suppliers
Suppliersrestaurant deals with supplier on JIT basis
otherwise problems with customers occur
Layout conditions must be adapted to needs - e.g. McDrive
new selling channels and faster process
Inventorystockbrokers drivingdown inventory = occurs at McDonalds
preparing only the food, which is already ordered
Scheduling based on forecasted demanddifferent Examples:Airline ticket Counter(consider flights)McDonald (5 min)Salon (elaborate,seasonal, weekly)
ExerciseCompany SuperCar is trying to reduce inventory and wants to install a kanban system for compressors on one of its assembly lines. Determine the number of kanbans (containers) needed. Given Setup cost = $10Annual holding cost per compressor = $100Annual usage = 25.000 (50 weeks x 5 days each x daily usage of 100 compressors)Size of one Container = 100Lead time = 3 daysSafety stock = days production of compressors
Determination the number of kanbansDemand during lead time = 300 ( =3 days x daily usage 100)Safety stock = 100 (= x daily production of 200)
Quiz 1What are the positive aspects of JIT-Scheduling ?
a) The ability to meet customer ordersb) Drives down inventory by allowing smaller lot sizesc) Reduces work-in-processd) All of them abovecorrect answer = d)Quiz 2What kind of System is the KANBAN - System?
a) Push-Systemb) Pull-Systemc) Horizontal - Systemd) Vertical - Systemcorrect answer = b)Quiz 3Where does the Kanban come from?
a) Germanyb) Chinac) Japan d) US c) JapanTrue or False?Inventory has only one positive aspect, which is availability; inventory has several negatives, including increased material handling, obsolescence, and damage.