Sakui – A story about abnormalities not listed on the inspection form:

In this post, I would like to discuss a story I read in the book “Total Quality Control for Management” by Masao Nemoto, a Toyota veteran.

The story was under the section “Discovery of Abnormalities and Quick Reporting”. The incident took place at Toyota Gosei’s Inazawa plant. There is a component called “fan shroud” made of plastic. This component is needed to adjust air flow and is situated near the engine fan. The operator, who was an older woman, was going to process the component as part of her routine work. She stopped and exclaimed “Sakui”, which means “soft to touch” in Japanese. She immediately called her squad leader who in turn stopped the production of the component to examine the component. Everything was checked, and everything was found to be working as expected except for the material. Another lot was used as the interim corrective action, and the components were determined to be as before. The suspect lot was sent back to the supplier and it was later found that the material was at fault. The resin was produced by “mixing of different size grains”. Since the discovery was early, the loss was minimal. As Nemoto notes, this was made possible by the older woman’s action, by reporting what felt “different” to her. She was not trained to look for this issue. The section chief wrote a letter of commendation to her and utilized this example as an opportunity for training.

A while back, I discussed the importance of fast feedback to increase the value of inspection. This story demonstrates an interesting point. If the abnormality or non-conformance is not listed on the inspection form, what should the worker do?

I liked this story since it points out many aspects of Toyota Production System. This also reminds me of Canon Production System, which is quite similar to Toyota Production System. Their mantra was TSS (Tomete – stop, Sugu – right away, and Shochi o toru – take measures to correct). Stopping the line is shunned in the traditional Taylor style production system. In the example above, the squad leader stopped the production to grasp the current condition, and took the right steps to continue production. Stopping the line when problems occur eliminates the need to stop the line for a longer time in the future. The operator has the right and responsibility to stop the line when there is a problem. This is also an opportunity for training. Stopping the line is one of the many counter-intuitive principles in Toyota Production System. The time spent stopping the line is tremendously decreased as days go by. This also encourages the operators to bring the problems to the surface. This encourages the operator to look for ways to improve the process as well.

Next time when your operator says “sakui”, heed to him/her.

Always keep on learning…