"You get more for less, this is lean. In practice, lean means creating more value for your customers with less resources."
Lean manufacturing applies to more than manufacturing or business economics with its costs of good sold metrics. Cooking can be lean when a gourmet dinner is prepared with everything perfectly thought out, with passion. Lean manufacturing is similar. It's a process of utilizing the available resources to their capacity. Lean design also utilizes a minimum number of components nearly to their capacity, but not beyond a reasonable factor of safety. In other words, a lean design is simple, where all parts interact with each other with a natural progression of contact forces, smooth distribution of thermal and mechanical stresses. A lean design naturally lends itself to lean manufacturing.
Orders of our custom engineered sight glasses have one common requirement: Short lead time. How fast can the product be delivered is the key in the competitive market. Rather than increasing the price and running on overtime, we remove all the wastes in productivity.
Overproduction: Do not produce more parts than the customer needs right now. In other words there is a balance between overproduction and avoiding long set-ups, batch manufacturing, or aggressive sales forecasts.
Over-processing: Overly tight tolerances should be avoided at the design stage, but there is no reason for multiple washes of the part or polishing it just one more time. Perfectionism is good to a point.
Over-movement: Moving the parts between operations sometimes cannot be avoided, sometimes it can be. Movement of people looking for tools or information can definitely be avoided.
Waiting: This is the biggest deal breaker. How many times did you look for some missing information on a drawing and then waited for answers from the design engineer? This is idle time, pure waste that can be avoided with better document control.
Under-inventory of raw materials: We are talking about relatively cheap inventory, such as raw materials on hand. This is a balancing act between sales forecasts and taking the financial risk of purchasing raw materials. Materials can be used for other projects. This minimizes the financial risk of carrying raw materials on the books. Common metals in bar stock, such as 6061 Aluminum, 304, 316 Stainless, 1018, 4043 Carbon steel, are some of the examples of stocking up on inventoried materials. The same goes with window materials such as Quartz, Borosilicate glass or Sapphire precut to sizes.
Re-work: Defects are expensive, they cost time and money to set up the part in the tool all over again. The saying "measure seven times, cut once" has never been more true in lean manufacturing.
Lean is good.
