Lean Manufacturing

Platypus?
by Sal Ganino

While thinking about this newsletter my mind wandered to the “Duck-billed Platypus”. Most of us are familiar with the anomaly of nature with its duck-bill and webbed feet, its body and tail resembling that of a beaver, but having the denser fur of an otter. It has several reptilian characteristics and even though the platypus’ body temperature is about five Celsius degrees below that of most mammals it is much more mammalian than reptilian.

Why bring this up for discussion? Because most manufacturing operations are a platypus, not totally a product environment (low variety, high volume) nor totally a process environment or job shop (low volume, high variety), yet they tend to gravitate toward the newest manufacturing management technique as if they were purely fowl, reptile, or mammal, and not easy to look at, but yet we continue to look for a single solution for all production woes.

In the early 1950’s Manufacturing Resource Planning was introduced to the manufacturing community offering a way to control inventory and production in a process environment; MRP excels in a job shop environment. A job shop environment is that of a Make-to-Order environment. Job shops don’t sell product they actual sell time on the equipment they own. Raw material is very limited in variety; a furniture maker’s raw material was wood. Yet the furniture maker could make anything and everything from that wood; tables and chairs, rocking horses, dressers, cradles, cribs you can add to this list, it goes on into the dead of night. Hershey and the other hand had to have cocoa, sugar, milk, aluminum foil and those little paper ribbons and yet he had only one product; milk chocolate (yes maybe two shapes the Hershey bar and the candy kiss, but still only one product).

In the 1970 the American manufacturing community heard about Just-In-Time (JIT) JIT was going to eliminate the need for us the carry inventory. But in the bearing industry of the 70’s the lead-time for steel bar and tube used in the manufacture of bearings, was twenty-six weeks (26) and increasing and the manufacture of a ball bearing took thirteen (13) weeks. Customer expected delivery of their bearing in three days. Bearing manufacturing is not a Make-to-Order environment, customers’ order-lead-time is far less than manufacturing-lead-time; inventory is mandatory. I had the pleasure several years ago to visit a local manufacturer of home vaporizers and humidifiers. These products are very seasonal; being required only in the cold, dry winter months. They worked through the summer and fall making vaporizers and humidifiers because when K-mart or Target, or CVS called and said send 1500 units here and 2000 units there, they wanted them there in three days.

In the 1980’s many of went through forty hours worth of brain numbing TQM training; you remember TQM (Total Quality Management); another good program where misunderstanding led to IDS (infant dead syndrome). In the late 1990’s we were bombarded with LEAN manufacturing and LEAN enterprise with prevaricators advocating LEAN means pull, one piece flow, kanban, and cellular manufacturing. Then came Six Sigma; each wanted to replace its predecessor.

MRP works quite effectively in a process or job shop environment, LEAN works exceptionally well in a product, or high volume limited variety environment. Therefore it is imperative that we not try to use one system to answers all production and manufacturing problems. MRP, LEAN and Six Sigma; each being nothing more than a bag of specialized tools; it is management’s responsibility to provide both the tools and the education and training that goes along of the selection of the proper tool and its effective use. A carpenter might have three different hammers in his tools bag; one 20 oz straight clawed hammer for forming, one 16 oz. curved clawed hammer for framing. And one 12 oz. curved clawed hammer for trim work.

Both MRP and LEAN are tools fro managing the operation; inventory and production. Six-Sigma is the bag of tools for solving production problems: product quality and process quality.