A Value Stream Map (VSM) is a process map that gives insights into the value creation process from order to delivery. It focuses on the process to the customer and is an ideal format to show relevant data at the place where they appear, e.g. the time and effort needed. Thereby, a VSM helps to challenge the existing production system, makes it easy to identify all sorts of waste, and shows stock levels (capital and cash which is bound up in the process). The information gathered is used for pinpointing opportunities for process improvements and to create the “Future State Map” of the process.
Step-by-step approach to map the current state (usually not all steps needed)
- Define the process: Customer and Process Mission (goal), value, start and stop point
- List activities, actors, systems and information flow
- Add inputs and outputs
- Add inventories
- Note process times, in-between times (average plus max, min and range if possible)
- Add basic process data (volumes, resources, batch sizes)
- Differentiate value-added and non-value added activities
- Establish how the process prioritizes work
- Identify the eight types of waste
- Calculate process cycle efficiency
- Helicopter view: What are the 2-3 key issues?
Questions to ask to get to the future state:
- What is the Takt Time of the downstream processes that are closest to the customer?
- Will you produce to a finished goods supermarket or directly to customer order?
- Where can you implement continuous flow processing?
- Where will you need to use supermarket pull systems or FIFO lanes to control production upstream?
- Which step is the pacemaker?
- How will you level the production mix at the pacemaker?
- How will you level the production volume at the pacemaker?
- What process improvements will be necessary to accomplish the future state?