Fast Lane

The concept of numerical control was developed through a U.S. Air Force contract given to the Massachusetts Institute of Technology and Giddings and Lewis in 1958 that involved driving a boring mill with a program punched into paper tape.

The Air Force needed a way to bring down the cost of production for aircraft parts and thus sought to automate rigid low volume production methods. They needed flexible manufacturing.

Independently, Kearney and Trecker came up with the automatic tool changer and manufacturing changed for all time. CNC driven coordinate measuring machines, robots and new families of machine tools and process control all evolved from those two seminal events.
 
Today, of course, CNC figures in low and high volume parts production but we were off to the races. The word flexibility trips from the lips of manufacturing executives around the globe. It could be their only way out.

Some 270 different model cars and light trucks with myriad versions, options and trim levels were sold in the U.S. last year and only 50 of them sold more than 100,000 units. The average light vehicle model was good for 62,000 sales, with the average automobile at 51,000 and the average truck at 75,000, which is also pretty interesting to ponder. Most important, though, these numbers will only shrink going forward.

Ford alone talks about launching 65 new products over the next five years and everyone is also sold on shortened product cycles — all of which augers for a more flexible approach.

So does tooling cost. Announcing Ford’s new Duratec 35, a 3.5L V-6 gasoline engine, Roman Krygier, group vice president of global manufacturing and quality, says Ford expects to save as much as $2 billion over the next decade through flexible manufacturing.

Engine plants at Lima and Cleveland, Ohio, Essex and Dagenham, the U.K., and Romeo, Mich., are all in the process of being converted to flexible CNC machining for major components.

Speed to market and shortened retooling times are other attractions of the approach. You don’t retool so much as you reprogram. Flexible plants are also less likely to drop into the overcapacity category whereas investments in hard tooling easily slip into the category of stranded assets.

I’ve been in at least two lean assembly plants this year that produce more than five different models on the same production line — Mitsubishi’s Normal, Ill., plant and the Sevelnord joint venture factory for PSA/Fiat in France. This is clearly a trend with most automakers clambering onboard.

Even the paint shop is being tackled. At some of its plants, Toyota can now produce any sequence of colors it wishes by arming its Kawasaki robots with paint canisters instead of paint supply lines — no purge, no cleanup. Just think of colors as tools. And change them at will. Now that’s flexibility.