I recently had the opportunity to visit Toyota in Japan. While there, I learned several things that were new to me. These thoughts came from individuals so I don’t know how widespread they are. I am still considering the implications of these ideas.
Here are some of the ideas:
- The primary reason they do kaizen at the individual and team level is not for process improvement. In fact, they accept almost every suggestion from the individual and team even if the suggestion results in a slight process decrease. The primary reason to do kaizen is to allow the workers a sense of control over their workplace.
- Kaizen did not really catch on with the workers until Toyota guaranteed employment. Otherwise the workers could have been improving themselves out of their job.
- Suppliers are responsible for replacing any defective parts in assembled cars. Therefore, the cost of allowing a defect to escape is high. This is why they perform so many tests on their parts to ensure that they are within the specifications.
- Kanban cards are used at Toyota for two purposes – identifying boxes of parts and ordering. For the latter, they are muda (waste). When a worker starts using the items in a box, he or she pulls the Kanban card from the box and puts it in a card box that is emptied periodically by a passing worker. The cards are then fed into a computer and transmitted to the corresponding vendors. The vendors print out the cards and use them as a physical indication to construct those parts. As part identifiers, the cards work fine. For ordering purposes, Kanban cards are redundant. Every car has an electronic tag and a list of components down to the number of screws needed to fasten a part. This information is used to visually indicate to the assembler which parts to put onto the car. The components could be re-ordered or placed in a batch for reordering as soon as they are used.
- There is more to ordering than just Kanban cards. The just-in-time ordering is supplemented by three month production plans that allow vendors to level production and thus decrease costs.
- Taiichi Ohno, the father of the Toyota Production System, did not trust software. He even pulled a software application off the production floor after it was installed.