What is ‘Mizu Sumashi’?
Mizu sumashi means Literally: whirligig (an object that spins or whirls)
Mizu Sumashi lost in Translation…
Mizu sumashi usually is translated as ‘water strider‘ (or ‘water skeeter‘) which then again should be translated as AMENBO in Japanese.
To make it worse: It seems that mr. Ohno once has made a minor mistake (Yes even he was not perfect…) and translated it as a water spider (a name you can find in many companies now…). The purist (like at Boeing) would call it a ‘water strider’.
However, a long story short;
Pull logistics
A Mizu Sumashi is a logistic function in a pull system; the person who delivers materials to the line and picks up its completed products.
In essence, the Mizu Sumashi rotates constantly from upstream (‘raw material’) to downstream (‘produced product’) and back again. In this way he has a perfect overview of the state of the process.
Highly qualified job
You would probably expect it to be a low-qualified job… nothing is less true! A real Mizu Sumashi ‘water strider’ is a very skilled person, who has a broad knowledge about the process that he/she is ‘feeding’.
Since there is only very limited material present at the line in a pull system (because there is a constant flow), the water strider immediately stops skeeting when there is a problem somewhere; this person then has the task to help get things going again, a kind of first aid so to say.