AMES KAN BAN CARDS
We designed our kanban cards to be uniquely identified, controlled tools, which would identify the product and the number to be produced. These cards are used in place of traditional paperwork orders. Control programs were created to track the cards and audit the production process. If a kanban card shows an "OPEN" status, it is considered to be WIP, and no changes to the card are allowed until the work order it created is completed and closed.
Each card contains the following:
• Four-digit kanban control number
• Part number and description
• Run quantity
• Next sequence number—this is added to the end of
the kanban control number to make a unique work
order number in the ERP system
• Last routing operation—when this operation is com
plete, the work order will be automatically closed.
• The last user, date, and time the kanban control
record was modified
• Work order "OPEN" or "CLOSED" flag
• The current work order (if status = OPEN) or the last
work order to be completed (if status = CLOSED)
• The last date and time a work order was issued and
the user who issued it
• The last operation completed
• The date, rime and user who completed the last opera
tion. If the work order status = "CLOSED", this would
be the date and rime the work order was completed.
Because we were eliminating paperwork orders, the
other information on the work order (bill of material and routing information) would have to be communicated by a different method. We developed "methods books" for each work center. The methods books identify the material required in that work center and what routing operations needed to be performed. Work centers are also provided with a daily schedule, which is based on due dates.
Batch items were easier to deal with than serialized items, so we did them first. All we needed to ensure was that the quantity called for on the kanban card was produced and reported. Additional software was created to automatically release, report, and close standard work orders for the quantity required by the kanban card. The original programs from our ERP system are actually used to post this information. What our new programs did was collect only the data we really needed to report. All other data required by our ERP was set to default values.
Because of the database controls set up for kanban card usage, the only thing shop floor personnel need to enter to activate any particular card is its control number. A work order is created in the ERP system for the appropriate quantity. As operations are completed, the user needs to let the computer know the card number and the sequence completed. If this was the last operation, the work order will be closed. In order to eliminate the problem of different quantities being reported at various operations, inventory movement is not recorded until the work order has be completed and closed.
Reporting is only done when the entire quantity called for on the kanban card is finished. If the kanban card is for 40 units, we expect 40 units, not 41, not 38. If units are scrapped, new parts must be produced to bring the completed quantity back to kanban card quantity. In our example, if I am down to 38 pieces, rather than the 40 called for, I need to make two more pieces.
To Be Continued