Toyota Management In Six-sigma

History of Management and Quality (cont.):

Significant accountability for product performance was lost in mass production compared with craft production.
This follows because the people producing the product each saw only a very small part of its creation. Yet, benefits of mass production included permitting a huge diversity of untrained people to contribute in a coordinated manner to production. This in turn permitted impressive numbers of units to be produced per hour.
It is also important to note that both craft and mass production continue to this day and could conceivably constitute profitable modes of production for certain products and services.
Mass production concepts contributed to intense specialization in other industrial sectors besides manufacturing and other areas of the corporation besides production.
Many companies divided into departments of marketing, design engineering, process engineering, production, service, purchasing, accounting, and quality. In each of these departments people provide only a small contribution to the sale of each unit or service. The need to counteract the negative effects of specialization at an organizational level has led to a quality movement called “concurrent engineering” in which people from multiple disciplines share information.
The interaction among production, design engineering, and marketing is considered particularly important, because design engineering often largely determines the final success of the product. Therefore, design engineers need input about customer needs from marketing and production realities from production.

The Toyota management:

The Toyota production system invented in part by Toyoda and Ohno, also called “lean production” and “just-in-time” (JIT), built in part upon innovations in U.S. supermarkets.
The multiple further innovations that Toyota developed in turn influenced many areas of management and quality-related thinking including increased outsourcing in supply-chain management. In the widely read book The Machine that Changed the World, Womack et al. (1991) explained how Toyota, using its management approach, was able to transform quickly a failing GM plant to produce at least as many units per day with roughly one half the personnel operating expense and with greatly improved quality by almost any measure.
This further fueled the thirst in the U.S. to learn from all things Japanese.
JIT creates accountability by having workers follow products through multiple operations in “U”-shaped cells (i.e., machines laid out in the shape of a “U”) and by implementing several policies that greatly reduces work-in-process (WIP) inventory.
To the maximum extent possible, units are made in batches of size one, i.e., creating a single unit of one type and then switching over to a single of another type of unit and so on. This approach requires frequent equipment set-ups.
To compensate, the workers put much effort into reducing set-up costs, including the time required for set-ups. Previously, many enterprises had never put effort into reducing set-ups because they did not fully appreciate the importance. Also, the total inventory at each stage in the process is generally regulated using kanban cards. When the cards for a station are all used up, the process shuts down the upstream station, which can result in shutting down entire supply chains.
The benefit is increased attention to the problems causing stoppage and (hopefully) permanent resolution.

“Finally, lean production generally includes an extensive debugging process; when a plant starts up with several stoppages, many people focus on and eliminate the problems. With small batch sizes, “U” shaped cells, and reduced WIP, process problems are quickly discovered before nonconforming units accumulate”.