Value Stream Mapping: A Tool for Process Improvement
Value stream mapping is a useful visualization tool for improving manufacturing processes.
Continuous improvement is at the top of the to-do list for manufacturers in process and discrete manufacturing companies. Industries continually look for ways to improve quality, increase output, meet customer demand, and provide innovations to set their products and processes apart from the competition.
More recently, the concept of lean has been used as a critical management strategy. As the Lean Enterprise Institute points out, the core of lean is the importance of the idea to maximize customer value while minimizing waste. Waste reduction is critical to any continuous improvement effort. Simply put, lean means creating more value for customers with fewer required internal resources.
Streamlining Your Process
A valuable tool for continuous improvement and waste reduction is value stream mapping (VSM), which is used to analyze and design the flow of materials and information required to bring a product to the customer. The concept is thought to have originated at Toyota and was originally known as “material and information flow mapping.” VSM can be applied to nearly any chain of manufacturing activities in glass and ceramics.
At a high level, a value stream map is a visualization tool for recording all of the processes that touch the product as it proceeds to the market or point of delivery (see Figure 1). A number of sources provide a definition, but one that truly provides a clear understanding of the concept is as follows:
A value stream map is typically created as a one-page flow chart depicting the current production path or design path of a product from the customer’s request to delivery. An important goal of value stream mapping is to identify processes that do not provide value so they can be improved. In lean production, value can be thought of as anything the customer is willing to pay for. Processes that do not provide value are called waste. Value stream maps document the current state of the value stream as well as the future state of the value stream and define any gaps between the two.1
Benefits of Value Stream Mapping
Valuestreamguru.com, a resource that aims to provide information, tools, and support on the business value stream, stresses that VSM can be used at the outset of a lean program to understand and identify the current process within a manufacturing organization. Though it is used to map information and materials through a production process, it also has several benefits:2
• Quick and easy to learn
• Helps portray the production process from the start to the end
• Finds bottlenecks and waste within the process
• Builds team synergy; it is a group exercise and can therefore involve the workforce as part of the lean improvement program
• When completed, a value stream map can be used as a visual improvement aid to document the transitions from current to a future state.
• Inexpensive (no software required); the only requirement is a large sheet of paper and a pencil (or a whiteboard and a marker)
• Can be easily critiqued and refined (e.g., with sticky notes) by the workforce to highlight existing problems
• Though extensively used in manufacturing, it can also be applied in the office processes that support manufacturing
In short, VSM is straightforward and easy to understand. Resources on the topic are readily available, and a number of online tutorials are available to get you started. Once you’re acquainted with the VSM icons, it is simple to create maps that depict the process and provide a simple pictorial view.
From a bottom-line perspective, VSM is a tool for reducing waste. As Taiichi Ohno, one of the originators of the concept, points out, “All we are doing is looking at the timeline from the moment the customer gives us an order to the point when we collect the cash. And we are reducing that timeline by removing the non-value-added wastes.”3 A recent user of value stream mapping affirms the benefits:
Where we found the most value in value stream mapping was being able to see and understand the whole process (value stream) where previously no one person ever did. We only knew our little sections of the process. This helped us look at optimizing the whole value stream instead of improving our sections, usually at the expense of the whole. We also started focusing on lead times as opposed to cost reduction. The maps also helped us prioritize our Kaizen efforts aimed at making a bigger impact for our customer instead of just a shotgun approach. We now see our Kaizen events as ‘strategic Kaizen.’ Finally, value stream maps helped us all agree on our current state and what our future state vision looks like. With this shared vision, we began to move forward as a team.4
A number of resources are available to help you get started (see Value Stream Mapping Resources sidebar). The first steps should involve some fundamentals, as highlighted by James Womack, a prominent lean expert:5
• The first step in any mapping activity is to identify a product family. This is the group of similar items that proceed through the same basic steps and equipment within the organization.
• The second step is to determine the current problem with the value stream for this product from the standpoint of the customer and from the standpoint of the organization. For example, your customers may be demanding a price reduction, the production organization may be producing a product that has a margin unacceptable to the business, or a quality problem may exist.
• Third, whatever the problem, it’s critical to have an agreement with the customer and within the organization on just what that problem is prior to the start of mapping. Otherwise, you risk focusing effort on the wrong problem, and it’s likely that mapping will fail to address the real issues. Or, equally likely, mapping will fail to spur any improvement in the process at all.
A number of books and training resources are available on this topic, but the focus here is not to recreate the wheel. To help you get started, following is a condensed step-by-step set of guidelines.6
Step 1: Gather Preliminary Information
- Examples of the required information might include product mix, volume, sales, quality issues, etc.
Step 2: Create a Product Quantity Routing Analysis
- This includes listing all of your customers and the products you supply for each.
Step 3: Group Customers and Sort Materials
- Group your customers and identify the products you provide for each.
Step 4: Sort Product Families by Process Sequence
- Identify product families according to a similar process sequence. This will help with mapping through the flow of your operations.
Step 5: Choose One Value Stream
- Map one value stream at a time to keep things simple. In order to decide where to start, consider things such as the highest percent of sales volume, a quality issue you are trying to solve, or market changes affecting demand.
Step 6: Create an Operations Flow Chart
- Create a flow chart of all of the operations in your value stream.
Step 7: Walk the Shop Floor
- The team needs to walk through the steps of your value stream where the work is being done, beginning to end. You will not be able to see wasted time or steps from the office.
Step 8: Collect the Data
- Data such as time should be collected. Conduct time studies where applicable, and involve the operators; they can be the best source for information when the data is unavailable.
Step 9: Construct the VSM
- On your sheet of paper (or whiteboard), construct the VSM using symbols to indicate what is happening at each process (refer to the symbols chart).
Step 10: Summarize the Data and Get the Big Picture
- As Chris Hoff points out, “When you have identified all the steps in your value stream and have filled in all the data applicable to your VSM, it’s time to put it all together. Remember, the point [is] to use your VSM to see where the value is being created and identify where wasteful activity occurs. In addition, looking at your VSM, take the list of Kaizen opportunities you identified in this process and begin prioritizing them by the level of impact an improvement will make to the flow of your value stream. This will give your team an organized plan of action from which to start making improvements to your value stream.”7
Improvement is a never-ending journey for all phases of the ceramic and glass industries. Price pressures will not let up in a global manufacturing environment. Applying VSM is a great tool to better understand the total process and plan improvements.
As Frank Garcia points out, “The use of value stream mapping can provide the ‘30,000 ft. view’ of the manufacturing operation … and sets the stage for the development of a coordinated implementation plan [that involves] a cross-functional team.”8 As a result, VSM can also be used to help develop the workforce in the application of other lean concepts for future improvements.
For additional information, contact the author at (607) 974-8179 or firstname.lastname@example.org.
1. “Value Stream Mapping,” http://searchmanufacturingerp.techtarget.com/definition/value-stream-mapping.
2. Lean Six Sigma Academy – “Let’s Create a Current State Value Stream Map!” http://lssacademy.com/2008/02/24/lets-create-a-current-state-value-stream-map/.
3. “Value Stream Mapping” http://courses.washington.edu/ie337/Value_Stream_Mapping.pdf.
4. Rother, Mike, Shook, John, Learning to See: Value Stream Mapping to Add Value and Eliminate MUDA, [Spiral-bound].
5. Womack, J. P., “Value Stream Mapping,” www.sme.org/Tertiary.aspx?id=30192&terms=value%20stream%20mapping%20%2bwomack
6. Hoff, Chris, “10 Steps to Successful Value Stream Mapping,” www.thefabricator.com/article/shopstrategies/10-steps-to-successful-value-stream-mapping.
8. Garcia, F.C., “Using Value Stream Mapping as a Strategic Planning and Implementation Tool,” www.lean-automation.com/pdf/Using%20Value%20White%20Paper.pdf.
Value Stream Mapping Resources
• Value Stream Guru, www.valuestreamguru.com/?p=60.
• Ohno, Taiichi, Toyota Production System–Beyond Large Scale Production, New York, Productivity Press, 1988, p. ix.
• Wroblewski, Mike, “There is Value in Value Stream Mapping,” www.reliableplant.com/Read/12819/value-stream-mapping.
• Rother, Mike, Shook, John, “Learning to See: Value Stream Mapping to Add Value and Eliminate MUDA,” Cambridge, Mass., The Lean Enterprise Institute, 2003.