Hello everyone. Last time, I wrote about “business process analysis”, which is one of the methods used in “internal research”.
This time, it will be Lean Six Sigma again, but I would like to write about “Value stream mapping (VSM)” which is the methods used in “Measure” phase in Lean Six Sigma, which is equal to “internal research” phase. This is familiar to problem solvers in the Lean Six Sigma world:), but other problem solvers may not have heard of it.
1. What is “Value Stream Mapping (VSM)”?
“Value stream mapping” is literally the map to draw the flow of “value”. The value here means “added value for the customer”. It is often abbreviated as “VSM” among lean six sigma practitioners.
Seeing is believing, let’s see what it’s like.
In short, it is almost the same as “business process analysis”, but there are some unique elements.
Element1: Width of scope (incl. customers)
Since this is to map the “flow of value (to the customer)”, this often includes customers and also suppliers on the other side. As a sense of level, it is about the same as “SIPOC” posted before. In fact, in many cases, VSM is written after making SIPOC.
Depending on the way of thinking, but this can be written in narrower scope by taking customers as “internal customers”. But in general, this is often written by including “external customers”.
Element2: “Information flow” and “Material flow”
In general business process analysis, “information flow” and “material flow” are not strictly separated, but VSM has a fixed format. In Fig1 above, the upper part is the “information flow” and the lower part is the “material flow”.
In addition, there are some other unique ones in detail format.
Black and white striped arrow: Push production
Bumpy line (Lead time ladder): Process time. I wrote about this in the previous post, “Business Process Analysis”, right?
If you need to express these elements strictly, I think it’s a good idea to follow these formats. However, personally, from the problem solver’s viewpoint, I believe that it is enough to clarify the flow of work to find out issues, rather than sticking to the detailed format. I think that “simplified version (see the figure below)” like this is enough. When it comes to this, there is no difference from normal business process analysis, right?
Yellow post-its: Process steps
Red circle: Wastes (see below)
Pink post-its: Issues
Bumpy line (Lead time ladder)
I think it’s easier to discuss at this level.
2. “7 wastes” or “8 wastes”?
As mentioned earlier, VSM is to map the “flow of value (to the customer)”. Each process step in VSM should be “value-adding activity” for the customer, but of course there are usually process steps that are not. It is called “Muda (wastes in Japanese)”.
In Lean Six Sigma, the basic idea is to increase “value add activities” to customers by creating VSM to identify and reduce “wastes” as much as possible.
There is a framework called “7 wastes” to extract wastes. It’s easier to remember if you take the first letter of them and remember as “Wide Tom”.
Waiting: Waste of wating
Inventory: Waste of inventory
Defects: Waste of defects
Excessive Processing: Waste of excessive processing
Transportation: Waste of transportation
Over production: Waste of over productio
Motion: Waste of motion
When discussing “What kind of wastes are there?” on VSM, rather than just thinking about it, it is convenient to discuss with this framework in mind, as it will allow you to efficiently identify any omissions. For example, you can use it like this:
The origin of Lean, the Toyota Production System, has “7 wastes”, but there is also “8 wastes” in the world. The difference is that in addition to the “7 wastes”, there is one more, “Non-utilized talent: the waste of unutilized talent”. Including this, it is said to be “DOWN TIME” by rearranging English.
I think it is ok to choose either one which is easier to remember. It is important to identify waste efficiently without omissions, rather than identifying the types of waste.
By the way, increasing the number of “frameworks” was important for problem solvers. Do you remember? (MECE)
3. Key points for “how to create” VSM: Be efficient in “workshop format”!
If you google how to make VSM, you will find a lot, so let me put only one link here.
The point of how to make “VSM” is the same as the “Business process analysis” I posted last time, I think that it is good to hold workshops that bring together relevant stakeholders and identify the process on the spot (I would like to write it on this blog). With this method, you can proceed while confirming with the people involved on the spot, so there is little rework and it is efficient in the end.
That’s all for this time, and I would like to continue from the next time onwards. Thank you for reading until the end.