Value Stream Mapping (VSM) is the “sharp tool” for optimizing production processes.
Written by | Banble Consulting
Image | AI Generated
Value Stream Mapping (VSM) is a visual tool used to analyze and improve production processes. In simple terms, it is like taking a “snapshot” of the production process, illustrating all the steps from raw materials entering the factory to finished products leaving the factory. Through it, one can clearly see which steps create value and which steps involve waste, such as inventory backlog and production waiting times. This allows companies to optimize processes, improve efficiency, and reduce costs.
In traditional manufacturing, Value Stream Mapping (VSM) acts like an “X-ray” of the production process, helping us see where the flow is smooth and where there are “traffic jams” from raw materials entering the factory to finished products leaving. Today, we will guide you step-by-step on how to draw a Value Stream Map, providing a basis for improving production processes.
1. First, understand why you need to draw a VSM
Identify waste: The production process hides a lot of waste, such as inventory backlog, production waiting, and over-processing. Once the VSM is drawn, the areas of waste become apparent, allowing us to pinpoint and eliminate them.
Promote collaboration: Production is not just the responsibility of one department; procurement, sales, and warehousing must all be interconnected. The VSM links various departments, helping everyone understand their roles in the process and facilitating smoother collaboration.
Set benchmarks: After drawing the current production process, it allows for the establishment of an ideal future process based on this benchmark, leading to continuous improvements in production efficiency and effectiveness.
2. Preparation before drawing
Assemble a team: Gather frontline workers, team leaders, workshop managers, and relevant personnel from procurement and logistics. These individuals interact with production daily and know best where the process flows smoothly and where it does not. Bringing them together ensures comprehensive information.
Collect data: Walk around the workshop to gather production layout diagrams, process flow charts, equipment parameter sheets, shift schedules, and material lists. These are the “resources” needed to draw the VSM; having them ensures confidence in the process.
Prepare tools: Get a large whiteboard, colorful sticky notes, markers, a ruler, and a camera (for capturing the process on-site). With the right tools, the work will proceed smoothly.
3. Officially start drawing the VSM (Current State Map)
Draw the product flow route: Start from the production starting point and locate the raw material warehouse. Use a blue sticky note to write “Raw Material Warehouse” and place it in the upper left corner of the whiteboard. Then, follow the flow of raw materials out of the warehouse to the processing equipment in the production workshop. For example, in a machining factory, raw steel plates are transported from the warehouse to the punching workshop.
Outline the processes: In the punching workshop, mark the punching equipment with a green sticky note labeled “Punching Process”. The finished parts then flow to the welding workshop; similarly, use a green sticky note to write “Welding Process” and place it appropriately, then draw an arrow connecting the “Punching Process” and the “Welding Process”.
Continue following the product through machining, painting, assembly, etc. At each process, place sticky notes and draw arrows until the product is completed and flows into the finished goods warehouse. In the lower right corner of the whiteboard, place a “Finished Goods Warehouse” sticky note and draw an arrow pointing to it, outlining the product flow route.
Supplement logistics and information flow: Logistics details include not only the path of the product itself but also how semi-finished and finished products are transported between processes. If forklifts are used for transportation, annotate “Forklift Transport” on the corresponding material path arrow. If there is a temporary storage area, such as a section in the welding workshop for temporarily storing punched parts, find the corresponding position on the whiteboard, place a sticky note labeled “Temporary Storage Area”, and draw an arrow connecting the punching workshop and the temporary storage area, indicating the storage duration, such as “Stored for 2 hours”.
Information flow: Information is the “nerve” that directs production. Starting from the sales order, this is the source that initiates production.
In the upper left corner of the whiteboard, write “Sales Order” and draw an arrow pointing to the workshop dispatch order. How is the workshop dispatch order communicated to each process? Is it verbally communicated by the workshop manager or distributed through a production management system? Clearly annotate the information flow arrows. If there is a malfunction in the equipment on the production line, how is the repair information communicated? Draw arrows at the corresponding positions and label them with terms like “Fault Reporting” and “Repair Instructions”, illustrating the back-and-forth flow of information.
Fill in data: Production cycle times should be written next to each process, indicating the processing time for that process. For example, the punching process takes an average of 10 minutes to punch one part, and the welding process takes 15 minutes to weld one component; these time data can be obtained from equipment parameter sheets or on-site observations. Also, calculate the transportation and waiting times between processes, such as 5 minutes to transport from the punching workshop to the welding workshop, and an average wait of 10 minutes after the punching process is completed before transportation; these should be noted on the corresponding arrows.
Inventory levels should be indicated at the raw material warehouse, temporary storage area, and finished goods warehouse. For instance, the raw material warehouse typically holds 1000 tons of steel plates, and the temporary storage area can stack a maximum of 200 punched parts; these numbers should be clearly written on the corresponding sticky notes to visually reflect inventory backlog situations.
Calculate time: Add up all the time from raw materials to finished products, including processing, transportation, and waiting times; this is the total production cycle. Calculate the actual value-added time (the time that truly changes the shape and performance of the product) as a percentage of the total time, with the remaining time being non-value-added time (wasted time). Keeping this in mind will provide direction for improvements.
4. Analyze problems based on the current state map
Identify bottleneck processes: Following the product flow chart, look for processes where the processing time significantly exceeds that of other processes or where there are frequent blockages in subsequent processes. For example, in the assembly process, it can only proceed once all preceding components are ready; if there are frequent issues in earlier processes, the assembly process will be “starving” and waiting. This process is the bottleneck and should be prioritized for improvement.
Identify major waste sources: Look for areas with severe inventory backlog, such as raw material warehouses that are constantly piled up with unused goods or temporary storage areas overflowing with parts; these are inventory wastes. Additionally, if products wait too long between processes before transportation, or if transportation is slow, these are waiting wastes. By comparing the data marked on the VSM, it becomes clear who the major waste “culprits” are.
Streamline information bottlenecks: Focus on the information flow arrows to see which segments have slow or erroneous information transmission. If the sales order information is frequently miscommunicated to the workshop, leading to production based on incorrect quantities or specifications, that is unproductive. If repair information for equipment is not communicated promptly, resulting in equipment breakdowns and halting the entire production line, these information bottlenecks must be addressed.
5. Draw the future state map (Target VSM)
Set improvement goals: Based on current issues, establish future targets to achieve. For example, reduce the total production cycle by 30%, lower inventory by 40%, and decrease bottleneck process processing time by 50%. These goals should align with the actual situation of the company and not be unrealistic.
Rearrange processes: For bottleneck processes, consider whether it is possible to increase equipment or optimize processes. If assembly is the bottleneck, can additional equipment be allocated to the assembly process, or can the assembly process be adjusted to increase speed? For inventory backlog, analyze whether just-in-time (JIT) production can be adopted, with raw materials delivered in smaller batches and more frequently, and temporary storage parts delivered precisely according to actual needs to reduce inventory. In terms of information flow, introduce a production management system (MES) to ensure that sales orders are synchronized in real-time with each process, and equipment faults can be reported with one click, making information transmission efficient and accurate. Rearrange the processes on the whiteboard, using sticky notes and arrows to indicate the new process layout, logistics, and information flow directions.
Calculate new time and costs: Estimate the new production cycle and inventory costs based on the future process. Compare the current and future states to see if the improvement goals can be achieved; if not ideal, adjust the process layout until the future state map meets the goals and is feasible.
6. Implement improvements to bring the future state map to life
Advance according to the map: Distribute the future state map to all departments; procurement should adjust raw material purchases according to the new plan, production departments should schedule production according to the new process and adjust equipment layout, and logistics departments should optimize transportation methods. Each department should follow the map step by step to turn the future process into reality.
Training and communication: Provide training for employees, explaining how the future process will operate, what changes exist compared to the old process, and emphasizing the significant changes to help employees become familiar with the new process and understand how to work according to the new requirements.
Supervise and adjust: During the implementation of improvements, minor issues are inevitable. Assign dedicated personnel to supervise and check whether each department is executing according to the future state map. If any problems arise in the new process, such as poor connections between processes or new equipment failures, promptly adjust and optimize to ensure smooth progress of improvements.
Case Study: A Machining Company Drawing VSM to Improve Production
A machining company in Ningbo, Zhejiang, previously faced frequent production issues, delayed deliveries, and inventory backlogs. They used our method to draw the VSM. First, they assembled a team to collect data and draw the current state map. Upon analysis, they found that the punching process was the bottleneck, with the temporary storage area behind it filled with punched parts, leading to slow inventory turnover. Information transmission relied on manual processes, which often resulted in errors. They set goals, drew the future state map, increased punching equipment, adopted kanban management to control inventory, and introduced an MES system for information management. They advanced according to the map, trained employees, and supervised adjustments. After a few months, the production cycle was reduced by 25%, inventory decreased by 35%, on-time delivery rates soared from 70% to 90%, and customer satisfaction increased significantly, leading to more orders.
In traditional manufacturing, Value Stream Mapping (VSM) is the “sharp tool” for optimizing production processes. As long as you diligently follow this practical tutorial to draw and utilize the VSM effectively, the production processes of your company will surely undergo significant changes, improving efficiency, reducing costs, and enhancing market competitiveness. Manufacturing partners, give it a try and let VSM lead your company to new heights.
