LEAN: Values Stream Mapping Basics

If you’ve read the post about SIPOC (in case not, read it here: https://www.lazyauditor.com/2018/02/09/lean-start-lean-journey-from-sipoc/), the next step to take is to start mapping out the important processes. This is called Value Stream Mapping (VSM).

Wikipedia defines VSM the following way: “Value-stream mapping is a lean-management method for analyzing the current state and designing a future state for the series of events that take a product or service from its beginning through to the customer. A value stream focuses on areas of a firm that add value to a product or service, whereas a value chain refers to all of the activities within a company.”

One important distinction to make in the beginning is that process mapping and value stream mapping are not the same thing:

  • Process maps are a fundamental part of standard work and are used to document specific tasks, roles and responsibilities;  the who, what, when, and how of detailed process steps. In the picture below, process map is the one on the left.
  • A value stream map is used to highlight and improve process timing and efficiency in the process, versus simply documenting the steps and owners.  VSM is shown on the right below.

VSM exercise is by no means one-day activity, but in my experience takes at least full work week, if counting also the prework.

STEP1: PREWORK

As mentioned in the beginning, the starting step usually is determine the value streams and processes that have the most impact on customer satisfaction and business needs.  SIPOC is excellent tool for this! Additionally, prework typically includes creating a project charter, defining the product family, assembling all necessary process data, and walking and documenting the current process. The extent and quality of the team preparation will directly impact the success of the value stream mapping event.

STEP2: MAPPING THE CURRENT STATE

the current state map is created using the information gathered during process walks and observation. An effective current state map is one that reflects what is really happening in the process, not what the team desire or expect to happen. The current state value stream map includes three key elements: an information flow, a material flow, and a lead time ladder.

  • Information flows from the external customer, into the process, and out to external suppliers.  Information flow may take the form of paper, electronic, or verbal instruction, and each will be identified by a unique icon on the map.
  • Material flow can be a part, document, or service that is being produced by the value stream. The process steps and details related to process time, quality, staffing and other key process indicators will be captured in this area.  Delay, wait, and inventory in the process will also be documented here.  Inventory could be parts or product in a manufacturing value stream or documents in a business or service value stream.
  • The lead time ladder captures the time required at and in between each process step.  These times will be summed and used to calculate the total lead time. Important aspect is to different show process time (i.e. time when something is being done) and time between actions (i.e. usually waste). Sum of the two is total lead time.

Using standard icons is highly suggested as it promotes common understanding and even the people outside of your organization will understand what’s going on in your value stream

STEP3: APPLY 9 LEAN GUIDELINES TO APPROACH FUTURE STATE

Once the current state is clearly described, you are ready to apply lean guidelines. The ultimate purpose of the below 9 lean guidelines is to have as little waste as possible in the value stream. It may not be possible to use every guideline, but each one should be considered and rationale should be documented for why a guideline was not used.

I will do a separate posting of each of them to discuss them in depth.

9 Lean Guidelines are then applied to desired future state (also called as Kaizen Burst) to show where homework needs to be done. E.g. it might be that there is some re-organization in the different teams to be done in order to achieve Single point initialization or FIFO -flow.

STEP4: IMPLEMENTATION PLAN

In the previous step, the kaizen bursts were identified (in the picture above you see 8, but in reality the number is much higher). Each kaizen burst should be specific enough that required tasks and due dates can be assigned.  One good way to follow up the progress of implementation is to use Kaizen newspaper (See a post about it here: https://www.lazyauditor.com/2018/02/03/quick-tips-kaizen-newspaper-template-to-follow-up-implementation-project/)

Value stream mapping is really effective tool to bring different teams together and provide rapid improvement for the value streams. It’s not the lightest -tool available, but once teams are familiar with it, the pull-effect usually to have more of them, is there.

In summary the steps in VSM are:

 

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Note of the Day

  • Consider starting your CIA certification journey from the Part 3. It's the longest, hardest and most difficult one. Everything after that is like a walk in a park :)