Programmable Automation Technologies. Daniel Kandray
formula, reducing it increases productivity. In fact, from a productivity viewpoint it is difficult to distinguish reducing labor cost from increasing labor output because the net effect is the same. However, it is listed as separate to emphasize that some automation strategies focus on improving the amount of output produced from the current number of workers whereas others specifically target reducing labor costs. Examples of labor cost reduction include any type of automation that reduces the number of workers or the time each worker spends in production.
Reduce or eliminate effects of labor shortages
Depending on the state of the local economy, a plant may have an abundance of available workers or a severe shortage. If the manufacturing process is particularly labor intensive, lack of workers can result in machine down time, less product, and overtime for the current workforce, each of which can have a detrimental effect on productivity. Making the process less labor intensive through automation allows it to better withstand periods of labor shortages. Thus, automation strategies geared to increase labor productivity and/or reduce labor costs should be considered.
Reduce or eliminate routine manual and clerical tasks
Reduction or elimination of routine tasks is often the first avenue to improving a process’s productivity. Automating these types of tasks, once again, frees up the worker to perform more value-added tasks. This inevitably leads to productivity improvements through reduced labor costs and/or improved worker productivity. A good example is the automation of the engineering drawing process with computer-aided drafting (CAD).
Improve worker safety
Any opportunity to provide a safer worker environment is a worthwhile investment in any process, not only from the obvious benefit of worker protection—management’s ethical responsibility—but also from a productivity standpoint. Down time due to accidents also decreases productivity by limiting output from the process. Yet, physical safeguards intended to protect the worker might also hamper output. A better approach would be to utilize automation and completely remove the worker from the dangerous work environment. This should be attempted even if a productivity gain is realized or not. An example of such precautionary automation might be utilization of a robot to remove parts from an injection press. For a worker to remove parts from the mold, the press door must be opened, which activates mechanical interlocks that prevent the mold from closing as the worker removes the parts. But, if a robot removes the parts, the worker is no longer required to reach in the press, thus removing him from the dangerous environment. Additionally, the press cycle time improves because opening and closing the door is removed from the process since the robot typically accesses the mold from the top of the machine.
Improve product quality
Improving a product’s quality yields many benefits to the manufacturer, including reduced waste—a plus for both the business and the environment, which makes for better brand image and higher sales. The impact on productivity is equally impressive. Reduced waste reduces material costs, which decreases inputs to the process, thus increasing productivity.
Reduce manufacturing lead time
Manufacturing lead time is a measure of how long it takes to create a product from the time the order is received by a manufacturer until the product is shipped. If through automation the manufacturing lead time is reduced for a process or a series of processes, output will increase over a given time period. If all other inputs remain unchanged, productivity will increase.
Some other reasons for automation often referenced in the literature, which are tied indirectly to productivity, include: (1) the high cost of not automating and (2) the existence of processes that simply cannot be done manually. The first is a somewhat obvious statement, regarding which the above list makes a strong case. In today’s economy productivity improvements are perhaps the only way to remain competitive. If a company is not competitive, it will not survive. Therefore, the cost of not automating will be in terms of lost customers and profits.
Consider the second of these, performing processes that cannot be done manually. Some processes may require too high of a degree of precision or be too small for the human hand to effect or have too complex a geometry. Ponder the manufacture of computer chips. Arun Radhakrishnan, writing in http://blogs.techrepublic.com.com/tech-news/?p=2050), pointed out that in 2008 Intel announced a new computer chip containing 2 billion transistors. Obviously, this can only be produced with the aid of automated machines; without the automation to manufacture it, the product could not be made and thus productivity would be zero.
Thus, there may be many reasons to automate, but the primary benefit to automating is improved productivity. When a company continuously improves productivity it is better able to absorb raw material cost increases, labor cost increases, increased energy prices, and other inflationary types of cost pressures—without passing those increases along to the customer. Thus, by improving productivity the company may realize other benefits including higher sales, better customer relations, and a larger market share. Although automation is not the only method to improve productivity, it is often a very effective method and should therefore be strongly investigated.
The why and where of automation are listed in the preceding section. We now turn to the how of automation. Typically, how a plant would automate is one of the more challenging aspects of the automation implementation process. One example was given already, that of employing a robot to perform material handling or adding a PLC to control the process. It is the intent of this section to provide some strategies that can be used to determine how a particular process might be automated.
In the aforementioned Automation, Production Systems, and Computer-Aided Manufacturing, 2nd ed. Groover introduced 10 strategies concerning how automation can be applied to manufacturing processes. Based on this list, five condensed “how to” strategies, geared specifically for programmable automation, are given here:
Minimize manufacturing process steps
As explained, a series of manufacturing process steps convert raw materials into some other higher value form. This strategy seeks to minimize the number of process steps. It does so by combining process steps, as might be done by the performance of more than one process on a single machine. Once operations are combined, it may then be possible to perform processes simultaneously. If processes cannot be combined, it may be possible to integrate several processes into a single machine or work cell. The integration could be in the form of several machines linked together with automated material handling devices. Thus, the cell will have the appearance of a single machine. Whichever method is used the result is the same: manufacturing process steps are minimized. Minimizing process steps can lead to large productivity gains by reducing input to the process and perhaps improving output rates from the minimized process.
Increase process flexibility
Improving process flexibility enables a machine or operation to process more product variety. The flexibility is achieved by minimizing or eliminating setup time typically required in changing a machine over to another product line. This is the essence of flexible automation systems. When a particular machine is able to process more product variety, the machine’s utilization increases, manufacturing lead time decreases and work in process is reduced. This can result in a substantial increase in productivity because inputs (time, labor, ...) are reduced, assuming of course that system output remains the same or increases. This strategy will also likely involve use of the all three programmable automation technologies.
Optimize material handling
Material handling is a non-value-added component of the material conversion process and thus should be optimized. Machines can often move material more consistently, accurately, and reliably than manual labor. Additionally, labor, freed up from performing material handling tasks can be displaced to perform value-added