Waiting Time – The 7 Types of Waste
What is Waiting Time?
Just imagine an operator interacting with a robot. Automatically you have to take care of the interface between man and machine – and the waiting time of both. Quite common the operator has to push and hold a two-hand button. Sure we have to take care of safety and do respect everything we can do to prevent the operator from taking any damage but there are tons of other solutions available without holding two buttons – preventing the operator from adding any value.
We like to use the term micro-stoppage: Micro-stroppages are often hard to identify. They are hidden in the process and often delay or interrupt processes not at the origin of the reason but more behind. For instance, in an assembly line of several operators. Once an operator is interrupted by any reason he will not forward the part to the next process on time. It will be obvious that the following process step will face waiting time as the part is not moved forward yet. More often micro-stops move along your process chain like a wave. Moving forward and backward, faster and slower frequently.
Lean Toolbox418 MB download
Thank you for subscribing.
Waiting Time – How to prevent?
In order to prevent waiting time several approaches seem suitable. In case of our operator on the picture above we can avoid a two hand button by implementing a plastic protection moving downwards once the part is moved to the robot and released mechanically once the robot stops. In case the operator has to wait for the machine to finish its cycle we can think of rebalance the station including also other stations around. Why not starting with the next part and move onwards the machined part once the robot finished.
In case of micro-stoppages visualization is the key term. The more you visualize the more waiting time (and waste in general) becomes obviously.