Detroit — A new approach to manufacturing now is making inroads in the US automobile industry. If this system is as successful as expected, a new breed of higher-quality and possibly less-costly cars will result. The system is widely credited for the high-quality cars built in Japan today.
Known as ''the Deming approach to statistical quality control,'' it consists of carefully monitoring the manufacturing process as each part is produced.
This approach differs greatly from the conventional manufacturing system in the auto industry and most other American industries, whereby the companies make several hundred, or even several thousand, parts, which are then inspected and the bad parts thrown away.
Dr. W. Edwards Deming, an 81-year-old American statistician and former college instructor, created the system in the 1940s. It's a modern variation of the statistical quality-control method developed by Dr. Walter A. Shewhart, a Bell Laboratories physicist, 50 years ago.
An important and fundamental difference between the two systems is that Dr. Deming insists, and with almost unanimous support, that management is responsible for at least 85 percent of all poor-quality parts, while the workers are to blame for only 15 percent.
In some manufacturing plants this might not be absolutely true, of course. But it's a very practical assumption, since it fixes responsibility for any poor-quality parts firmly on one person, the boss.
Many factors - poor machines, poor maintenance, poor material, poor engineering, poor environment, or poor workers - can cause the production of defective parts. But the boss has the ultimate responsibility for the defects, because he usually puts these elements into the system and only he can change them if poor parts result.
An important byproduct of the Deming system, and one that makes it popular with the auto companies even when sales are down, is that it also substantially raises productivity.
This, of course, reduces costs and potentially increases profits.
Statistical quality control can improve productivity several ways. But two important things it does is to reduce the number of parts scrapped and the number of parts that must be reworked before they're acceptable.
Thus far, the auto companies are taking to the Deming idea in varying degrees of enthusiasm. Ford Motor Company and the Pontiac Division of General Motors are most enthusiastic. Chrysler Corporation and the other GM divisions largely agree that statistical quality control is the way to go, although they disagree somewhat with Deming's exact approach.
Statistical quality control, stimulated by Drs. Shewhart and Deming, got its first real test during World War II. The US government used it to help defense contractors make high-quality military products.
The American auto companies, impressed with the statistical system's effectiveness during the war, began using it in the late 1940s. But for a variety of reasons, including the huge demand for cars, the system was gradually abandoned.
Professor Deming updated it and tried to interest the US manufacturers in the process, but they largely rebuffed him. Then, in July 1950, he made a milestone speech for no fee on the subject to 45 top Japanese executives at the Industry Club of Japan in Tokyo.
The result was - and this is largely acknowledged by the Japanese - Japan was transformed from a country that produced some of the poorest-quality products in the world to a country that's now renowned for its high quality.
Deming, in fact, is referred to in Japan as the ''father of Japanese quality.'' A measure of his esteem is the award given annually for the Japanese person or group that has made the greatest contribution to improving quality in the past year. It's simply known as the Deming Award.
In the summer of 1980, NBC-TV televised a white-paper program in which Deming was lavishly and apparently properly praised for the big improvement in Japanese manufacturing quality.
Suddenly, executives from GM and Ford began appearing at his seminars and a good relationship soon developed between Deming and the US auto companies. This was difficult for both sides. Deming had to remember his earlier rebuffs. And the auto executives, widely considered the world leaders in automobile manufacturing, now had humbly to revive a system adopted by their competitors and one they had earlier abandoned.
Nevertheless, Deming and three of his supporters - statisticians steeped in the Deming approach - now meet regularly with Ford and GM officials. In addition , meetings are also starting with members of the United Automobile Workers union and with suppliers.
Ford Motor Company recently had Deming explain his methods to the senior executives of 250 Ford suppliers. Since suppliers produce 50 to 65 percent of each car's parts, depending on the manufacturer, their participation is just as important as the basic car producer's.
Many of these larger suppliers are diversified into other US industries. So chances are good that the seeds of statistical quality now being dropped by Deming will spread throughout the entire US manufacturing complex.
Most important, if this renaissance succeeds, it's going to result in much-improved American-built cars.