Process selection, which determines how the product or service will be produced, involves four phases of technological decisions:
Major Technological choice: Does technology exist to produce the product? Are there competing technologies among which to choose? Should innovations be licensed from elsewhere, such as foreign countries, or should an internal effort be made to develop the needed technology? The importance of the major technological choice phase is highlighted by such recent developments as microchips and gene splicing. Although the major technological choice is largely the province of engineers, chemists, bio-geneticists, and other technical specialists, top managers should comprehend as fully as possible the technology, its likely evolution and the alternatives.
Minor Technological Choice: Once the major technological choice is made, there may be a number of minor technological process alternatives available. The operations manager is involved in evaluating alternative transformation processes for costs and for consistency with the desired product and capacity plans. Should the process be continuous? A continuous process, which is carried out 24 hours a day to avoid expensive start ups and shutdowns, is used by the steel and chemical industries, among others. An assembly line process follows the same series of steps to mass produce each item, but need not run 24 hours a day. Examples are the automobile and ready to wear clothing industries. Job shop processes produce items in small lots, perhaps custom made for a given market or customer. Examples are lumber yards and aircraft manufacturers.
Specific Component Choice: What type of equipment (and degree of automation) should be used? Should the equipment be dedicated (tied to a specific purpose) or general purpose (leaving open the possibility of using it to make other products)? To what degree should machines replace people in performing and controlling the work? Increasingly, human workers are being used to program and monitor automated equipment, rather than dong the work themselves.
This trend began in the early 1960s, when numerically controlled (NC) lathes, milling machines and drill presses began to show up on the shop floor. These were dedicated machines, meaning they performed a specific task according to instructions contained in a program written on plastic mylar tape. (There was no memory, as in a computer) The strength of NC machines is that they perform operations with a consistency and reliability that far exceeds those of the normal machinist. Their weakness is the downtime and expense involved in changing their setup – the tasks they are ready to perform.
This barrier was overcome, to some extent, when newly developed microcomputer chips were used to create computerized numerical control (CNC) machines. These machines are easier to reprogram and set up for another task, but they cost anywhere from $50,000 to $500,000 depending on their size and the complexity of the operations they can perform. Obviously such a capital investment cannot be taken lightly. It requires good planning and operations management. The same is true of flexible manufacturing systems (FMS), which combine CNC machines in flexible systems of production that can be easily and efficiently set up to produce batches of different products.
CAD/CAM (computer aided design and computer automated manufacturing) is an integrated approach in which the computer software that is used to design a product can be used to translate the design into a computer program that will operate the NC or CNC machine. Typically, only companies that have high volume production can afford to invest in such a system.
CIM (computer integrated manufacturing) is an even more integrated approach that incorporates CAD / CAM, robots and materials requirement planning (MRP) – a computerized approach to managing inventory.
Most industrial robots are basically computer controlled mechanical arms that can be equipped with grippers, vacuum cups, painting guns, welding torches, or other tools. As such they are good choices for moving and handling hazardous materials (hot ingots, radioactive rods) or for performing tasks that require precision under hazardous conditions (spray painting and welding). Robots, for example can paint for hours and never suffer ill effects from breathing the fumes. In the future, more sophisticated robots will be equipped with video imaging systems, allowing them to “see” their work, and on board computers, allowing them to perform certain tasks independently.
Process Flow Choice: How should the product or service flow through the operations system? This final process selection step determines how materials and products will move through the system. Assembly drawings, assembly charts, route sheets, and process flow charts are used to analyze process flow. Analysis may lead to re-sequencing, combining or eliminating operations to reduce materials handling and storage costs. In general, the less storage and delay involved in the process, the better.