(This is the seventh in a series of deeper dives into the 8 lean wastes.)
The lean waste known as excess motion is exactly that – having to move more often, over a greater distance, with greater effort than might be truly necessary.
In our set of daily operations we all have to move. The process of creating value for customers all but necessitates our physical moving of something – raw materials, finished product, even keys on the computer keyboard – but while we can’t completely eliminate it from our processes it is certainly worth our while to reduce the time and effort we devote to it.
While we previously covered transportation as a lean waste, excess motion is geared toward how we transport ourselves. What are some examples of how we are excessively transporting ourselves?
The more time we spend walking, the more time we are spending time not creating value.
There are two components that comprise the measured impact of “transporting ourselves” – the time/distance we consume by moving, and the frequency in which we must complete this motion. Another way to look at it…
Excessive Motion Waste = (time or distance consumed by moving in one cycle) x (frequency in which process is completed)
So to reduce the impact of excess motion, we have to look at the time or distance consumed by a cycle AND how often this occurs! We can help prevent some of this from happening by moving process steps closer together (maybe copier users have the copier more centrally located or each person has their own individual desktop-based printer) and optimizing work cell layout so that process step order is also the order of the layout.
This first part has only been about moving ourselves over measurable distances. Another thing we need to look for is excessive motion when we are not transporting ourselves – excessive effort or process steps that are reversed or undone.
The opening photo for this post is of an operator reaching far above his head to complete a task. The time devoted to reaching AND the effort/strain for this operator could facilitate wasted time (especially if back problems affect the operator’s availability to work).
Reaching down to pick up cups frequently can create ergonomic hazards. What if the cups were kept at the proper level of use (operator arm level) and at a closer location to where they’d be used (beside soda fountain instead of below)?
A lean tool used to facilitate this time recovery is a lean tool called point-of-use-storage (POUS). This tool necessitates that tools/components are stored right where they are needed or used. Special tools are easily within arm’s slight reach to pick up. In this photo, the trays contain components needed by the operator while using the fixture and tool in the center of the work bench.
As was just indicated, another excess motion is where something is reversed or undone. What if, during the normal course of assembly, the operator must put down the components and reverse a fixture each time the process is completed? For example, what if the operator that affixes hardware (screws) to a substrate (large plastic cover) sets the cover on the fixture to complete some steps before picking up the cover and turning it around or over to work on more hardware installations? What if files in a filing cabinet are incorrectly ordered – now the user has to fix the problem and consume more time.
So where can excess motion be reduced? Here are some things to consider: