by Kevin J. Duggan
Creating Mixed Model Value Streams: Practical Lean Techniques for Building to Demand provides a step-by-step approach to extend beyond the basics of value stream mapping and create future states. The approach is illustrated through a case study of Electro-Motion Control (EMC) Supply Company, “a manufacturer of a variety of parts and products for the motion control and electronic industries”. The case study shows how to create future state maps in the real world where there are multiple products, varying cycle times, and fluctuating demand.
The book is written with the assumption that the readers have a basic knowledge of value stream mapping. The book is organized in the sequence of implementing mixed model value streams. Each part provides the concepts necessary for implementation along with examples, graphs, and calculations using the EMC case study. The focus is applying lean into high-mix environments to eliminate waste. The implementation of lean value stream starts by creating a pacemaker (the single point of scheduling) that can respond to the customer.
The first part is an introduction to lean and eliminating waste. The challenges of the real factory are presented including high product mix, shared resources, and information flows. The book then covers how to see and address these challenges using value stream mapping and where to start this process. The Electro-Motion Control (EMC) Supply Company is then introduced with an overview of the business and its challenges.
Part two discusses product families and the pacemaker. There are four key questions to ask:
The third part is flow at the pacemaker. The concept of operator balance charts is introduced to balance cycle time close to the takt time. Balancing flow for the mix is explained with several options when work content exceeds the takt time. Next, the topic of creating standard work for the mix is discussed as a key element to achieve flow in a high-mix environment.
Part four discusses pitch and scheduling. In particular, this chapter covers how to create pitch at the pacemaker and how to schedule the mix at the pacemaker.
The next part covers handling changes in customer demand. A method to manage changes in demand presented is smoothing demand with dynamic supermarkets.
Part six of the book ties all of the concepts together to transform the complex environment with mixed models and changing demands into a lean environment. This final section presents the future state for the EMC case study and what steps the improvement team will focus on next.
A CD-ROM is also included which contains spreadsheets for sorting products into families and calculating equipment needs.
Creating Mixed Model Value Streams is a very easy to read and follow workbook. The writing is clear and concise. The concepts are easy to follow through the illustration of the EMC case study.