Value Stream Mapping (VSM) is a proven tool. Suitable for a wide range of industries and processes, VSM is ideal for creating positive organizational changes, developing effective future conditions and producing whole-system benefits in cost, quality and flexibility. In short, it helps eliminate waste.
However, like any tool, VSM must be used correctly. This means avoiding the common mistakes that cancel the mapping process. Below are tips for developing an accurate VSM. Not only do these tips improve the accuracy of your map and facilitate the mapping process, they will also help you reap its benefits throughout the system.
But first, we need to define a value stream. It includes all the activities required to bring a product from “raw materials” into the hands of the customer or to provide service to a target audience. Michael Porter, author of Competitive Advantage: Creating and Sustain Superior Performance, was among the first to talk about value chains and value streams. In his definition of a value stream, he includes primary activities, such as inbound logistics, and support activities, such as procurement. Porter relates these activities to gain a competitive advantage.
One key to the value of power mapping suggested by Porter’s definition is to define the product or service to be mapped. In other words, make sure you have a value stream that needs to be mapped out before entering the process, as the goal is to identify system-wide waste and then remove it. Unfortunately, some VSM apply in situations where there is no product or control part, such as in product development processes. Make sure that there is a repeatable action or control part to follow before creating a value stream map. Otherwise, you’re just wasting time and resources.
Another key to developing a VAM is to observe performance first hand. While many value streams are simple, many are also complex. In some cases, the production process or service delivery efforts are long and tedious. In other cases, it may take a few days or a couple of weeks or the person developing the process to fill out the card quickly. All this makes it difficult to develop a value stream map.
In addition, not much of what goes on in the day-to-day running of a business – phone calls, interruptions, work priorities – is not stored on a computer or in a person’s memory. So depending on technical standards to fill in the information fields and determine potential savings, it will not work, nor will it try to develop a card while sitting in your office. While the map may be technically correct, you will miss many of the activities that actually happen on the floor.
Unfortunately, these activities affect production time and the value of the product. Therefore, you must observe the product as it is produced or the service while it is being delivered to determine which activities add value and which do not. While sometimes difficult to do, it is important to gather accurate data for your VSM. Otherwise, create a process card, not a value stream card.
Also, make sure you follow the product that is in production or the service provided throughout. Sometimes an observer follows the employee through a long drawn out production process. When he or she stops trading the product, the observer follows the employee instead of the control part. This can spell disaster.
Let’s say, for example, that the product is a patient in a medical office. When the physician finishes his examination, the observer should follow the patient, not the nurse updating the patient’s chart. If the observer is following the nurse, he or she will map out the nurse’s work, not the work done on the control section, which stopped when the patient left home.
Also, be aware of product families when developing a VSM. Most companies produce more than one product family. Sometimes it gets complicated after a single product family because the observer did a poor job of identifying the key product family before hand. By not identifying the product family, the observer risks being distracted and following the wrong treatment path.
Two common problem areas in value stream mapping ignore shared resources and double counting time. These pitfalls can cancel the accuracy of a value stream card.
Most companies have shared resources. These resources – which can be people, assembly lines or equipment – often support multiple product families. If the observer forgets to identify these shared resources when developing a value stream map, the map will be incorrect. Identify the shared resources in a value stream ahead of time. Forgetting to do this gives wrong estimates for things like cycle times. And that in turn will affect the end product of the card.
Also, make sure you understand exactly what goes into an information box and what is a processing step. Usually changed in an information box, but what about the travel time. The key is to separate the actual work involved in completing the product or service from the things that make up the inventory. Long shifts cause the bearing to build, but what about long-distance travel? Both activities could possibly be removed because they both cause the inventory to build.
These tips will help you develop accurate value cards. The cards, in turn, will help cut waste from your production processes or services in delivering sequence, streamlining operations, cutting costs and improving customer service. More importantly, they help you reap the benefits that VSM provides, making your efforts both productive and profitable.