Manufacturing Systems Design

Manufacturing Systems Design is the art and science of developing, building, and implementing the methods by which products are manufactured. Manufacturing Systems Design is a broad field that involves a variety of different disciplines, including engineering, design, technology development, labor relations, organizational behavior, marketing, and business development. The history of modern Manufacturing Systems Design has its roots in the quest to develop a system for manufacturing guns using a series of interchangeable parts that was pursued by Eli Whitney and other American inventors and manufacturers in the late 1700s and early 1800s. In the early 1900s, the American engineer Frederick Winslow Taylor developed and promoted a popular theory of Manufacturing Systems Design called Scientific Management. The Scientific Management system sought to maximize productivity and profitability in factories by using scientific methods to determine how each step in the manufacturing process could be performed at maximum efficiency. Modern-day Manufacturing Systems Design continues to employ some of the theories developed by Taylor, but more frequently focuses on the development and implementation of Lean Manufacturing Techniques, “greener” methods which emphasize speed, versatility, and the elimination of all waste in the production process. Lean Manufacturing methods were primarily developed and refined by the Toyota Motor Company in Japan. The recent application of Lean methods to American-based industries has helped to strengthen and diversify the country's manufacturing base, and has paid dividends in both economic and environmental terms.

Keywords: American System of Manufacture; Interchangeable Parts; Just-In-Time Production; Lean Manufacturing; Scientific Management; Toyota Production System; Value Stream Mapping

Manufacturing > Manufacturing Systems Design

Overview

Eli Whitney, John Hall, & the American System of Manufacture

Up until the beginning of the 19th century, most products were made on a small scale by skilled craftsmen following their own individual systems and standards. This method of manufacturing called for specialized workers who were often trained through apprenticeships with accomplished craftsmen. It was not a system that was designed to manufacture products on a large scale, or to a consistent standard.

Since individual goods were handmade, the craftsmen system made it difficult to repair broken products, as replacement pieces had to be hand-crafted specifically to match the piece that was broken. This was an expensive, difficult and time-consuming process.

The history of modern Manufacturing Systems Design is often linked to efforts of American inventor Eli Whitney and other industrialists to create a system of manufacturing guns using interchangeable parts in the late 1700s and early 1800s. The thinking of Whitney and others was that if guns were all made to the same set of standards, then it would be possible to produce identical replacement parts, thus making it easier to repair a broken gun.

Most historians agree that the idea of creating products with interchangeable parts dates far back beyond Whitney, however. The French gunsmith Honoré Leblanc is credited with presenting the same idea to the French court years before Whitney brought the idea to American government officials. In fact, it is thought that Thomas Jefferson saw a presentation by Leblanc while he was in France and brought the idea back with him to the United States.

Though Whitney was attempting to build guns with a standardized process as early as 1798, his early attempts produced mixed results. The inventor John H. Hall is credited with creating the first truly successful interchangeable system at the Harper's Ferry armory in Virginia between 1820 and 1840. Over this 20-year period, Hall developed a series of machines that were able to create metal parts to match exact specifications.

The advances that Hall, Whitney, and other manufacturers made in the early 1800s helped to usher in the American System of Manufacture, a system in which most products went from being made by hand in small, individual batches to being made in larger batches by using a series of machines.

The Industrial Revolution & the Rise of the Machine

The Industrial Revolution of the 1800s and early 1900s produced another significant change in the manufacturing process, in which products went from being produced by machines on a relatively small scale to being produced by machines on a much larger scale using large machines powered by new sources of energy such as iron, steel, electricity, coal, and gasoline.

According to an article by Gerhard Rempel on the Ecology.com website, the Industrial Revolution also led to new developments in transportation and communication, including the invention and use of the steam locomotive, the steamship, and later the automobile, airplane, telegraph, and radio.

The Industrial Revolution created changes in the social fabric as well. According to Rempel, it helped to usher in the development of new cities, created a new middle class of factory workers, devalued the skilled work of artisans, and led to the creation of large industrial complexes around large centers of resources.

Frederick Taylor & Scientific Management

Perhaps the first prominent thinker to approach the manufacturing process as a science was Frederick Winslow Taylor, who published his theories in the book Principles of Scientific Management in 1911. In this book, Taylor set out to prove that the country's workplaces were suffering a great loss through worker inefficiency (both intentional and unintentional) in almost every daily task. Taylor also argued that the remedy for this inefficiency could be found in the systematic or scientific management of workers, rather than trying to locate or create workers with superhuman abilities.

As outlined by Taylor in his book, the theory of Scientific Management contends that there is a scientifically correct method to perform nearly any task to the greatest level of efficiency, and that this method can be determined through careful scientific analysis of worker practices. The theory further states that these scientifically determined methods should be used to replace the traditional "rule of thumb" work methods that employees have learned through on-the-job training and observing their co-workers.

Taylor claimed that his principles of Scientific Management would be able to significantly increase worker output while at the same time make workers happier. This idea is based on the assumption that working more efficiently will lead to an increase in production, which will in turn make the factory more profitable. With production and profitability up, factory managers can afford to pay workers more money, which makes them happier, and helps to encourage them to continue working at maximum efficiency.

Taylor felt that such a large improvement in productivity was possible due to the "systematic soldiering" that he identified as endemic among American workers. Taylor defined soldiering as the practice of doing just enough work to get by, without actually working anywhere near full capacity. It is a practice, Taylor wrote, that is heavily encouraged by peer-pressure from co-workers.

When it comes to sporting events such as baseball or cricket, Taylor noted, it is fully expected for a man to give his best effort at all times. If he gave only a half-hearted effort, Taylor noted, then he would likely be criticized by his teammates.

Taylor said that when a man is working, however, he does as little as he possibly can over the course of the day. If he tried too hard, he would be abused by his fellow workers for making them look bad, and he would also be worried that his increase in productivity might lead to others losing their jobs.

To correct this practice of soldiering, Taylor's theory called for a harmonious relationship between workers and management, one where managers select and train the right workers for the right jobs, and then help them achieve their goals by setting out tasks for them to complete each day, and directing them to use scientifically proven methods to complete the work at each step in the process.

In an effort to validate his theories on Scientific Management, Taylor spent time working with the pig iron handlers at the Bethlehem Steel Company in Bethlehem, Penn. He writes about his experiences in his book.

When Taylor and his team first arrived at the steel company, he writes, they found a gang of 75 workers who were loading 90 pound pieces of pig iron at a rate of 12 tons per man per day.

Taylor attempted to prove through his theories of scientific management that a first-class pig iron handler should be able to handle much more than that — between 47 and 48 tons of iron per day — without becoming exhausted or burnt out.

Taylor arrived at this ideal loading rate through an extensive series of tests that were designed to determine how long a man could reasonably be expected to bear weight during the course of the workday. The Taylor team determined that it was possible for men to increase their lifting capacity if they correctly balanced periods of rest with periods of exertion.

Taylor's first step was to observe the workmen in action to determine which of the crew members were physically capable of increasing their workload to 47-48 tons per day. Then he talked to each man separately.

The first subject was told that he would earn more money if he did exactly what he was told to do by one of Taylor's team members, exactly when he was told to do it.

A member of Taylor's team then directed the man through a day's work, telling him when to work and when to rest. The result was that the man was able to lift 47 1/2 tons per day. Several other members of the team were subsequently approached by the Taylor team, and they each agreed to unquestionably follow direction in return for higher pay. Each of the men was in turn able to subsequently increase his workload.

While Taylor's book paints a rosy picture of factory life under the Scientific Management system, he also acknowledges that it will not always work as planned. "It is not here claimed that any single panacea exists for all of the troubles of the working-people or of employers. As long as some people are born lazy or inefficient, and others are born greedy and brutal, as long as vice and crime are with us, just so long will a certain amount of poverty, misery, and unhappiness be with us also."

Taylor can also be fairly criticized for taking a dim view of the laboring class, a view which may have resulted from his own clashes with workers as a factory manager. Taylor assumes that workers are dumb, dull people who will be motivated to work harder solely by the possibility of making more money. He also assumes that workers are not bright enough to grasp the principles of scientific management on their own, and thus have to mindlessly follow orders from managers of superior intellect.

In their book A Perfect Mess, authors Eric Abrahamson and David Freedman note that strict Taylorism was discredited in 1920 by a series of studies at the Hawthorne Electrical Plant. The so-called Hawthorne Effect said that work tended to improve no matter what changes were made so long as the workers were being observed by management.

The Hawthorne studies determined that a change as innocuous as adjusting the intensity of the lights could increase worker productivity if managers were seen to be observing workers in action, thereby calling into question Taylor's assertions that his "scientifically correct" methods of performing tasks were responsible for the increase in productivity.

Nevertheless, Taylor's theories about the importance of finding efficient ways to perform tasks, and of doing things faster, neater, and more efficiently continues to play a major part in modern systems of Manufacturing Design.

Lean Manufacturing

The Lean Manufacturing System (also known as the Toyota Production System or Just-In-Time Manufacturing) differs from Scientific Management in that the focus is not to produce as much product as possible using the most efficient methods, but to produce only what is needed, when it is needed; in other words, making only what has been ordered by customers in order to reduce the amount of capital that is tied up (or lost) in unnecessary labor, material, storage, or transportation costs.

The Lean Manufacturing System emphasizes a proactive, ever-evolving approach to manufacturing design, where workers and management are always looking for ways to improve the process and to eliminate problems as they occur. These efforts help to significantly reduce the number of faulty products that are created due to errors in the production process. The goal is to produce a high-quality product, when— and only when — it is needed.

The company that has been most responsible for developing and codifying Lean Production Techniques is Toyota Motors. According to the Toyota Motors website, the Toyota Production System, or TPS, is based on the identification and elimination of all waste and requires all aspects of the production process to concentrate on achieving this goal.

The system was developed in the 1920s and 30s. Kiichiro Toyodasecond president of the Toyota Motor Corporation, believedthat the ideal conditions for making things are created when "machines, facilities, and people work together to add value without generating any waste."The principles of the Toyota Production System have since been adopted by many Western European and American companies. However, says Marc Helmond in Supply Chain Europe, “In many companies only 20-30% of activity actually adds value. In reality, a large number of businesses have already introduced such principles but have yet to apply this concept to their suppliers.” (Helmond, 2011)

In the United States, there are a number of government agencies at the state and federal level that work to encourage lean manufacturing growth. The Environmental Protection Agency (EPA), an advocate of lean production methods for their environmental benefits, defines Lean Manufacturing as "a business model and collection of methods that help to eliminate waste while delivering quality products on time and at least cost."

While cutting down on costs makes sense from a business perspective, it also makes sense environmentally, the EPA points out, as Lean techniques help to make the manufacturing process as efficient as possible, cutting down on the amount of natural resources used, energy expended and waste created by the production process.

The Toyota Production System identifies two main principles of lean manufacturing systems.

Jidoka

The first principle is called jidoka, or "the human touch." Jidoka calls for active human oversight over every step of the production process in order to establish and maintain quality control. When a problem with the production process occurs, factory workers are expected to immediately detect the problem and shut down the system until the problem is resolved.

That way, only products that meet the correct quality standards are passed on to the next level of the production process. To avoid unnecessary delays, a lean production system will typically divide production into a series of multi-functional u-shaped cells, rather than one large, linear assembly line. The machines themselves are typically multi-functional units that can be quickly modified to perform different tasks.

Thus if a problem occurs at one point in the process, there is typically another machine that can be quickly adjusted to perform the required task, or an identical work station at another cell that can be used.

Just-In-Time Manufacturing

The second major principal of a Lean production system, according to the Toyota website, is the idea of "Just-in-Time" production. The Just-in-Time system is designed to produce just enough products to fulfill the need that exists at the next step of the production process. This system is commonly referred to as the pull system, where the level of customer demand acts to pull the production process forward.

Waste Elimination

Another major component of the Lean Manufacturing System is the elimination of all waste.

In his article on Lean Principles, Jerry Kilpatrick lists a number of commonly identified areas of waste. These include:

• Overproduction/Excess Inventory: Producing more products or parts than are needed for any step in the manufacturing process is viewed as waste in the lean production system. Overproduction requires unnecessary labor, ties up materials and capital that could be used for other, more crucial production functions, creates logistical problems and takes up space in the factory or the warehouse.

Value Stream Mapping (VSM) has emerged as a tool for identifying areas of waste. After specific processes are mapped, VSM can determine the sources of waste and ways to eliminate it. (Ocak, 2011)

• Waiting: The key to Just-In-Time production is that the products arrive exactly when they are needed in the assembly process. If the products arrive too early, as is the case in overproduction, then they sit around taking up space and cluttering the workplace. If the products do not arrive by the time they are needed, this can bring the entire cycle to a halt. Reconfiguring a production system so that it works on a Just-in-Time production is often one of the biggest challenges of implementing a Lean system.
• Transportation: Just as waiting unnecessarily delays the production process and decreases efficiency, so does the unnecessary transportation of products and materials. The Just-In-Time production system calls for materials to arrive just at the moment that they are needed, and right to the place where they are going to be used. Any time spent transporting materials from storage to the point of use is viewed as waste in the Lean System.
• Defective Materials/Non-Value Added Processing: Non-value added processing is any work that is done to a product that is not an inherent part of the production process. This includes reworking products that were built incorrectly and modifying or trimming products that were built with imperfections. This extra work does not add value to the process, because it is merely expending time, resources and effort to get products to match the standards that they should have been built to in the first place. Under an ideal lean manufacturing system, non-value added processing should be eliminated, because quality control is built into every step of the process.
• Poor Workflow/Underused Employees: Like Frederick Taylor's theories on Scientific Management, the Lean Manufacturing system views poor workflow, poor training and the failure to use the most efficient work methods as waste. Unlike Scientific Management, the Lean system views employees as resources of creativity and talent that can be tapped into in order to improve the production process. With quality control built into every step of the production process by way of human oversight, it is important that factory workers take a proactive approach to detecting and solving problems.

Case Studies in Lean Manufacturing

The EPA website features several success stories from companies that have recently implemented lean techniques. One example is Apollo Hardwoods, a Pennsylvania-based company that employed lean techniques upon startup in 2003 in order to create a more efficient method for manufacturing cherry plywood veneer.

In taking a lean approach to manufacturing systems design, Apollo was hoping to avoid some of the problems that are experienced by typical, large-scale veneer manufacturers.

In particular, veneer manufacturers typically have to invest a great deal of capital into large-scale pieces of equipment. Not only do these machines represent a significant financial investment, they also use a tremendous amount of energy, and by nature have to be used on a large-scale basis in order for the owner to derive maximum benefit.

The traditional veneer process also creates a significant amount of scrap and waste, primarily because the process is designed to produce 12-foot slices of veneer, while the typical size of a finished piece of veneer is less than six feet. The Apollo design team regarded the extra work that it took to trim the veneer down to size as non-value added processing. It would be much easier, they reasoned, to create veneer in slices closer to six feet.

Since the type of equipment needed to operate on a six-foot basis was not available on the market, the Apollo team decided to develop its own equipment in house. The equipment created ended up costing less than half of traditional veneer processing equipment, according to the EPA case study.

The Apollo team also designed its factory to operate in a series of small, self-contained cells. Unlike a traditional linear assembly line system where the overall capacity is determined by the capacity of each machine in the assembly line, the cell-oriented system allowed the company to replicate cells in order to increase production to meet customer demand.

The smaller, leaner production techniques also provided environmental benefits, as six-foot pieces of veneer could be made from younger cherry trees, which were easier to find and replace than the larger, old growth trees that were needed to create the 12-foot slices.

Another EPA case study details the successful application of lean manufacturing techniques to an existing factory.

From October 2006 to March 2007, the Columbia Paint and Coatings factory in Spokane, Washington, embarked on a pilot program with the Washington State Department of Ecology and Washington Manufacturing Services to apply lean techniques to the factory's current practices in order to save money and reduce the factory's environmental impact.

The project activities included a Lean 101 Workshop to introduce workers and managers to the lean manufacturing process, a Value Stream Mapping workshop that identified areas of possible savings, and three "get 'r' done" employee action events that were designed to implement new lean operating methods.

The goals of the project were to develop a production schedule that was driven by customer demand, to streamline the quality control process, and to improve the organization and flow of materials through the factory. Factory workers also made changes to the plant layout and made improvements to the oil decanting and shrink-wrapping process.

On the economic side, the new lean techniques helped to reduce production times, material loss, damaged products, operator travel time and overall downtime throughout the factory.

From an organizational standpoint, the project resulted in the creation of a new, dedicated layout for materials and supplies. Rather than storing raw materials in the first available space, factory workers created an organizational system that was based on the frequency of use and likely product pairings. The team also established an easily understandable signal system for managing inventory.

Environmentally, the process helped to reduce raw material waste, wastewater discharge, volatile organic compound (VOC) emissions, and hazardous waste. One major environmental success was that the team discovered that wash water from white paints could be absorbed into other paints, rather than being disposed of. This not only cut down on the amount of waste water created by the factory, but also saved $17,000 in disposal costs, and reduced the amount of time that employees had to spend handling wastewater.

Conclusion

Updates to manufacturing systems and ways of thinking about them are, at least in part, driven by consumers. “The desire among consumers, whether retailers or end-users, for greener solutions is real and growing. Lean began as a way to reduce inventory, save factory floor space, and help cash flow. Today it points the way towards more sustainable manufacturing.” (Joyappa, 2012)

Terms & Concepts

American System of Manufacture: A system for producing products using small machines to create identical, interchangeable parts.

Lean Manufacturing: An approach to manufacturing that emphasizes flexibility, versatility, and the complete elimination of all waste. Lean manufacturing is also known as Just-In-Time Manufacturing and the Toyota Production System.

Rule of Thumb: The process of handing down the best practices for completing a task from generation to generation. Many of the laborers studied by Frederick Taylor used rule of thumb techniques prior to the introduction of his scientifically-determined techniques.

Scientific Management: An approach to manufacturing, first advanced by Frederick Taylor, in which scientific methods are used to determine the ways in which work tasks can be performed to peak efficiency.

Soldiering: A term used by Frederick Taylor to describe the practice of working just hard enough to get by, without putting in a full day's worth of effort.

Value Stream Mapping: A visual representation of the entire manufacturing process, used as a way to identify areas of waste, as well as areas for possible improvement

Bibliography

Eli Whitney Museum and Workshop. (n.d.). The factory. Retrieved October 22, 2007, from http://www.eliwhitney.org/factory.htm

Environmental Protection Agency. (n.d.). Apollo hardwoods. Retrieved December 2, 2007, from http://www.epa.gov/lean/studies/apollo.htm

Grimshaw, D. (n.d.). From interchangeable parts to visual basic, a brief history. Retrieved November 14, 2007, from http://www.ryerson.ca/~dgrimsha/courses/cps841/Interchangeable.html

Helmold, M. (2011). Lean principles: driving value in upstream supply chain management. Supply Chain Europe, 20, 48-49. Retrieved November 13, 2013, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=69714791&site=ehost-live

Joyappa, P. (2012). Lean and green manufacturing. Flexible Packaging, 14, 42-45. Retrieved November 13, 2013, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=84528142&site=ehost-live

Kilpatrick, J. (2003). Lean principles. Retrieved November 5, 2007, from http://www.mep.org/textfiles/LeanPrinciples.pdf

National Parks Service. (n.d.). John H. Hall at Harpers Ferry. Retrieved November 24, 2007, from http://www.nps.gov/archive/hafe/hall.htm

Ocak, Z. (2011). Streamlining waste. Industrial Engineer: IE, 43, 38-40. Retrieved November 13, 2013, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=60501243&site=ehost-live

Rempel, G. (n.d.). The Industrial Revolution. Retrieved December 2, 2007, from http://www.ecology.com/archived-links/industrial-revolution/index.html

Ross & Associates Environmental Consulting, Ltd. (2007). Lean & environmental case study: Columbia Paint & Coatings. Retrieved November 9, 2007, from http://www.epa.gov/lean/studies/Columbia.pdf

Taylor, F. W. (1911). Principles of scientific management. New York, NY: Harper & Bros.

Suggested Reading

Brewer, J.C. (2004). Do I have to be flexible? Automotive Industries, 184, 42-43. Retrieved December 3, 2007, from EBSCO Online Database Business Source Premier. http://search.ebscohost.com/login.aspx?direct=true&db=buh&AN=15515777&site=ehost-live

Dahlgaard-Park, S., Chen, C., Jang, J., & Dahlgaard, J. J. (2013). Diagnosing and prognosticating the quality movement – a review on the 25 years quality literature (1987–2011). Total Quality Management & Business Excellence, 24(1/2), 1-18. Retrieved November 13, 2013, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=85408678&site=ehost-live

Trebilcock, B. (2006). Leading manufacturing trends. Modern Materials Handling, 61, 47-51. Retrieved December 3, 2007, from EBSCO Online Database Business Source Premier. http://search.ebscohost.com/login.aspx?direct=true&db=buh&AN=20811582&site=ehost-live

Wenbin, Z., Juangi, Y., Dengzhe, M., Ye, J. & Xiumin, F. (2006). Production engineering-oriented virtual factory: A planning cell-based approach to manufacturing systems design. International Journal of Advanced Manufacturing Technology, 28(9/10), 957-965. Retrieved December 3, 2007, from EBSCO Online Database Academic Search Complete. http://search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=20535643&site=ehost-live