October 25, 2001
The number of opportunities to steer your company wrong during a move toward lean manufacturing are myriad. Knowing a few of the common ones may help you achieve your goals without a lot of headaches.
Shops trying to create a lean manufacturing environment within their businesses sometimes make common mistakes that could be avoided with forethought and a little knowledge of the pitfalls faced by lean pioneers past.
Job shops, make-to-order shops, and engineer-to-order operations need to maintain a level of flexibility that original equipment manufacturers (OEMs) such as Toyota seldom have to think about. Being able to turn on a dime, make a product from scratch, build a prototype, or fabricate an item that never will be made again takes a special attitude, a unique set of skills, and a nimble and flexible manufacturing system.
One-piece flow through hard-wired machines is not as viable an option in job shops as it might be in a pure assembly operation in which product lines are known and predictable. Does this rule out becoming lean for job shops? No. Hundreds of make-to-order shops have applied tools from the Toyota Production System toolbox to improve their performance dramatically while still maintaining flexibility.
Hooking machines together before they are capable and reliable is one of the most common mistakes shops make when working toward lean.
Departmentalization can hide problems for years. Two wrongs do not make a right, and two incapable machines do not get better just because you marry them into a cell. Make sure that you do not increase your chances for downtime and excessive setup time by welding machines together in a premature effort to achieve one-piece flow. It is tempting and romantic to show your customer a cellular manufacturing arrangement, but if your machines are in breakdown or setup mode 47 percent of the time, you cripple your ability to meet your customers' needs. Focus on the fundamentals.
Du Pont's famous Safety Training Observation Program (STOP) teaches that 96 percent of all accidents are behavior-related. Having lean initiatives come undone similarly can be traced back to failure to change behavior. Many companies fail to apply enough effort to changing their standard work procedures (behavior) when they implement changes. Modifying the work process is necessary to prevent lapsing into the old way of doing things and giving the new process a chance to become a habit.
If, on the other hand, you change only physical things, those things will get lost or broken or replaced when no one is looking. In no time you'll be back to the old condition.
Some teams take a shotgun approach to trimming down their organizations. The result: slow progress.
Getting to the obvious problems-the low-hanging fruit-is fine, especially if there is financial bleeding somewhere in the organization. However, teams need to realize that running without a clear vision with the kaizen approach actually can add to the overall time necessary to transform a company. Kaizen is just a tool, much like any other tool in the world-class manufacturer's toolbox.
Of course, the techniques of Kaizen should be used where appropriate, but Kaizen is not a one-size-fits-all tool. A better approach would be to drill to the bedrock and focus on the fundamental issues faced by a particular value stream within your business, preferably within a model line that represents a major business segment. Apply as many of the tools as possible in a controlled atmosphere. These tools include setup reduction, machine reliability, defined standard work, and balancing the work content among team members. Then you'll have a meaningful model, which you then can use to train other teams within the organization.
Toyota focuses on single-minute exchange of dies (SMED), and that company has taught industry by example never to accept setup times as a fixed amount. It can be very expensive for job shops to try to match Toyota's le