Overview of Proposed Book
The main concept of this book—Lean Work Design—comes directly from our view that lean operations result from how the work is designed. To have lean operations we must have a lean work design. Lean Work Design uses three existing theories of work design to study lean operations and to identify the principles involved in realizing lean operations. First, it relies on systems theory to conceptualize how lean operations differ from other work designs. Second, it uses Hopp and Spearman’s (2004) definition of lean as a system that buffers throughput against variance using minimal buffering costs, where these buffering costs are the cost of having an inventory buffer, a capacity buffer, and a lead time buffer. Third, it uses organizational information processing theory to understand how the lean work design allows different types of information to be processed. So, lean work design is viewed in this book as a work design that attempts to maximize system productivity and effectiveness while minimizing the costs of the system buffers. It does this by achieving tighter integration of its system components, which in turn is accomplished by using work design methods that incorporate a systems view of the organization. So, work design methods not only create specialized tasks to perform an operation but also integrate tasks, which seek to coordinate performance of these operational tasks to accomplish effective, efficient delivery of the service and product. We attempt to demonstrate that appropriate work design methods consciously seek to incorporate a systems view and coordination into the design of a production or service process.
Taiichi Ohno states that the Toyota Production System (TPS) was developed to address the needs of making multiple products in small quantities for a wide variety of customers. To do this TPS had to eliminate “waste” or muda, which refers to all work accomplished that does not add value to the customer. In this way, the TPS system recognizes the resource constraints faced by companies in today’s environment. Lean operations emerged at Toyota in response to the need to meet a low and varied demand with restricted resources and it evolved as Toyota responded to the competitive global automobile manufacturing market. Lean uses techniques common in many production systems, but it adapted them to the unique situation facing Toyota at that time. One example of a business studied by managers at Toyota was Ford Motor Company. Henry Ford’s (2003) book is often cited for its insights into work design.
Ford suggested that managers view all inventory and time as units of human labor so that everyone would recognize the waste involved in materials sitting or being scrapped or reworked. Ford said:
The time element in manufacturing stretches from the moment the raw material is separated from the earth to the moment when the finished product is delivered to the ultimate consumer. (Ford 2002, p. 99)
Ford further recognized the need for planning and coordination to avoid waste stating that:
Time waste differs from material waste in that there can be no salvage. The easiest of all wastes, and the hardest to correct, is this waste of time, because wasted time does not litter the floor like wasted material. (Ford 2002, p. 101)
Since Henry Ford wrote his book, managers and researchers have recognized that work design must include not only consideration of how particular tasks are performed but also the context within which these tasks are to be performed. This requires managers to learn about the process—taking a system or process view—and let this knowledge guide the process design. It is increasingly apparent that knowledge is a critical input into production processes and that many production processes require the application of multiple types of specialized knowledge. Knowledge here not only refers to knowledge of the latest manufacturing technology but also knowledge of how to coordinate operations. So an important role of the firm is the integration of the different kinds of knowledge. For example, Galbraith (1977) established that the appropriate choice of an organization design depends on the amount of uncertainty in its environment and in its system and consequently how much information processing it must do to complete and coordinate its tasks. Tushman and Nadler (1978) further developed this understanding by explaining that an organization designer had to find an appropriate match between the information processing requirements to complete and coordinate a set of tasks and the information processing capacity available in the company to do that. This is a consequence of the law of requisite variety (Ashby 1956), which states that the variability (or flexibility) of any control solution must be equal to or greater than the variability of the system being controlled. Similarly, the responsiveness of any control solution should be appropriate for the level of uncertainty inherent to the system being controlled.
Lean work designs were originally created by trial and error on the shop floor using general principles. The inventors of lean work design used all the existing principles of work design that they found valuable. To do this, they intently studied the work designs of many other businesses to obtain ideas. For example, Taiichi Ohno describes how in the 1960s as vice-president of Toyota he led the improvement of Ford’s workflow system to create the “Toyota production system, [which] however, is not just a production system. … [but is] a management system adapted to today’s era of global markets and high-level computerized information systems” (Ohno 1988, p. xv). Currently, we know much more about how to achieve a lean work design. The tools and practices to accomplish this are examined in this book.
Structure of Proposed Book
This book introduces the standard practices and tools of Lean operations which are a key to creating a Lean Work Design. Chapter 1 covers visible control and 5S before Chapter 2 extends the principle of visible control to Total Productive Maintenance. Chapter 3 addresses set-up time reduction through Single-Minute-Exchange-of-Die. Facility layout is discussed in Chapter 4. How visual signaling is used to create visible control is discussed in Chapter 5 before Chapter 6 explores how pull systems use both visible control and visual signaling. Value stream mapping and how to make the production process visible is discussed in Chapter 7. Chapter 8 then outlines Total Quality Management before the principles of continuous improvement are explored in Chapter 9. How standardization helps to maintain improvements and to create a work structure is then explained in Chapter 10. Finally the book closes with an introduction to Hoshin Kanri, a concept for coordinating the different principles and tools discussed in this book in Chapter 11. A final summary is provided in Chapter 12.
This book is an attempt to show that we can postulate a very small number of assumptions and utilize them to explain a very large spectrum of industrial phenomena. You the reader can judge whether or not the logic of the book’s derivation from its assumptions to the phenomena we see daily in our plants is so flawless that you call it common sense. Incidentally, common sense is not so common and is the highest praise we give to a chain of logical conclusions. If you do, you basically have taken science from the ivory tower of academia and put it where it belongs, within the reach of every one of us and made it applicable to what we see around us. (Goldratt and Cox 2004, p. 2)
References
Ashby, W.R. 1956. An Introduction to Cybernetics. London: Chapman & Hall, Ltd.
Ford, H. 2002. Today and Tomorrow: Commemorative Edition of Ford’s 1926 Classic. Originally Published by Doubleday, Page & Company, Reprinted Boca Raton, FL: Taylor & Francis Group, LLC, CRC Press.
Galbraith, J.R. 1977. Organization Design. 1st ed. Reading, MA: Addison-Wesley Publishing Company.
Goldratt, E.M., and J. Cox. 2004. The Goal: A Process of Ongoing Improvement. 3rd revised ed. Great Barrington, MA: North River Press.
Hopp, W.J., and M.L. Spearman. 2004. “To Pull or Not to Pull: What Is the Question?” Manufacturing & Service Operations Management 6, no. 2, pp. 133–48.
Ohno, T. 1988. Toyota Production System: Beyond Large-Scale Production. Published in Japanese by Diamond, Inc., Tokyo, Japan, 1978. Translation into English by Productivity Press, Boca Raton, FL: Taylor & Francis Group, LLC, CRC Press.
Shingo, S. 1989. A Study of the Toyota Production System from and Industrial Engineering Viewpoint. 1st revised ed. Cambridge, MA: Productivity Press.
Tushman, M.L., and D.A. Nadler. 1978. “Information Processing as an Integrating Concept in Organizational Design.” The Academy of Management Review 3, no. 3, pp. 613–24.