FIXED BATCH KANBAN SYSTEM AND LEAD TIME CONTROL

FIXED BATCH KANBAN SYSTEM AND LEAD TIME CONTROL Alain Prioul JUNE 2010

FIXED BATCH KANBAN SYSTEM AND Property of Faurecia - Duplication prohibited LEAD TIME CONTROL 2

PULL SYSTEM - MIFA Demand : forecast/firm PC & L d pa rts A B C Leveling board Pu rc ha se Batch building Process 2 A B C Process 1 Customer TPA Property of Faurecia - Duplication prohibited F. G. Shopstock Process Stagnation Production Lead Time NO LEAD TIME CONTROL NO CONTROL OF THE FLOW 3

BATCH PRODUCTION Demand : forecast/firm PC & L d pa rts A B C Leveling board Pu rc ha se Batch building Property of Faurecia - Duplication prohibited Process 2 A B C Process 1 A B Stock A = Lead time of A Customer TPA C A time 4

FIXED BATCH CONCEPT A B C A Fixed ? Property of Faurecia - Duplication prohibited Fixed duration Fixed quantity ? Nb of Kb in one lot vary with Production Cycle Time of A or B or C Packaging of A or B or C 5

FIXED QUANTITY BATCH : LEAD TIME VARIATION Batch is longer than standard Stock A A B B Property of Faurecia - Duplication prohibited Lead Time A C C A A Stock Shortage A l If production duration of B or C is longer, Lead Time of A is longer. Same for B and C. l Same consequence if tool change time is longer than standard. 6

POOR LEVELING ALSO IMPACTS LEAD TIME A B C B A Lead Time A Unleveled Withdrawals A B C Property of Faurecia - Duplication prohibited PIK WK Schedule change C B A Shopstock 7

Property of Faurecia - Duplication prohibited CAUSES OF LEAD TIME VARIATION l Production time longer than standard l Tool change longer than standard l Unleveled withdrawals l Stagnation of information Even when we fix the quantity of Kanban in a batch, we do not control the Lead Time 8

PRODUCTION PATTERN A 8 h B 10 h Property of Faurecia - Duplication prohibited 12 h B A 8 h C 10 h A 14 h C 12 h B 16 h A 14 h 16 h Schedule is pre-define Changeovers are planned LEAD TIME IS UNDER CONTROL 9

PRODUCTION PATTERN Production pattern A B C A B A PIK A B B C Daily demand C Property of Faurecia - Duplication prohibited Pre-requisites Demand stability Line reliability OPR control 10

Production pattern Advantages l Good visualization of future changeover l Synchronization with preceding or next process is possible Property of Faurecia - Duplication prohibited l Strong incentive for beeing lean Disadvantages l Becomes difficult when law runners are not predictable l No adaptation to demand variations 11

TO REMEMBER Property of Faurecia - Duplication prohibited Fixed batch Kanban system do not ensure systematically stability of Lead Time Control is key to control plant performance 12

Property of Faurecia - Duplication prohibited 13