Control of Manufacturing Systems

Effective functioning requires that manufacturers control their operations through careful monitoring on a consistent basis. This article describes eight operations intrinsic to manufacturing: The sales function, ordering function, inventory management, product tracking, labor tracking, quality control, distribution, and overall planning and control. It discusses how these affect the manufacturing process and examines two crucial elements for the control of manufacturing systems: Good communication and effective tools. Finally, the article defines terms and concepts that are relevant to the topic of the control of manufacturing systems.

Keywords Enterprise Resource Planning (ERP); Flexible Manufacturing System (FMS); Just-in-time (JIT); Kanban; Lean Manufacturing; Manufacture; Manufacturing Resource Planning (MRPII); Material Requirements Planning (MRP); Radio Frequency Identification (RFID); Remanufacturing; RFID Tag; Stochastic

Manufacturing > Control of Manufacturing Systems

Overview

Effective functioning requires that manufacturers control their operations through careful monitoring on a consistent basis. For purposes of this article, we will consider the control of the following eight operations that are intrinsic to manufacturing:

  • Sales Function
  • Ordering Function
  • Inventory Management
  • Product Tracking
  • Labor Tracking
  • Quality Control
  • Distribution
  • Overall Planning and Control.

In order to successfully control these eight operations in the manufacturing process (the "manufacturing systems"), a manufacturer needs to employ a control strategy that capitalizes on two crucial elements:

  • Good Communication
  • Appropriate Tools.

Note: Although manufacturing may involve the making of products by hand or by machine, this article will focus on manufacturing by machine.

Applications

This section briefly describes nine operations that are intrinsic to the manufacturing process and examines two crucial elements in the control of manufacturing systems.

Operations Intrinsic to the Manufacturing Process

Eight operations are intrinsic to the manufacturing process. Although there may be additional operations within a manufacturing company, such as a separate purchasing or marketing department, we will consider the control of manufacturing systems to encompass the control of the following eight operations:

  • Sales Function
  • Ordering Function
  • Inventory Management
  • Product Tracking
  • Labor Tracking
  • Quality Control
  • Distribution
  • Overall Planning and Control.

Sales Function

The first operation that is intrinsic to the manufacturing process is the sales function. Sales drive many subsequent functions in the manufacturing process including ordering, inventory management, product tracking, job control, distribution, and overall planning. A good sales team strikes the proper balance between selling a product and overselling. Overselling a product occurs when a salesperson promises a customer more than the manufacturer can comfortably deliver. For example, the customer agrees to purchase more products than can be produced or delivered within the agreed upon delivery date.

Ordering Function

The second operation that is intrinsic to the manufacturing process is the ordering function. The ordering of the manufactured product for customers usually originates from the sales team. The ordering of the supplies and parts necessary to manufacture products usually originates from employees with a specific purchasing role. As you might expect, it is essential that orders — whether for products or parts and supplies — are accurately placed and tracked.

Inventory Management

The third operation that is intrinsic to the manufacturing process is inventory management. Inventory management is central to controlling manufacturing systems. In fact, modern automation advances have resulted from lean manufacturing strategies for inventory management, such as Just-in-time (JIT) and kanban techniques.

Product Tracking

The fourth operation that is intrinsic to the manufacturing process is product tracking. Product tracking refers to methods for identifying the status and progression of all stages of a product from each step of manufacture to final distribution to the customer. The goal is to be able to quickly identify the product's stage at any time during the progression.

Labor Tracking

The fifth operation that is intrinsic to the manufacturing process is labor tracking. Labor tracking refers to procedures for quickly determining the number and identities of employees who are performing specific job functions, on specific products, at specific times. Labor costs constitute a large part of a manufacturer's budget and the availability of labor affects a manufacturer's production rate, so labor tracking is crucial to controlling manufacturing systems.

Quality Control

The sixth operation that is intrinsic to the manufacturing process is quality control. Quality control refers to the methods that ensure the product is being manufactured meets the customer's specifications at a satisfactory cost to the manufacturer. Quality control can be initiated before the manufacturing process even begins through a process known as "design for manufacturability (DFM)." DFM involves the tailoring of product designs to eliminate manufacturing difficulties and minimize costs (Rosen, 2007). Quality control can also be implemented by performing inspection and testing procedures during various stages of the manufacturing process. Manufacturers will usually employ more than one procedure for quality control.

Distribution

The seventh operation that is intrinsic to the manufacturing process is distribution. Distribution refers to delivery of the manufactured product from the manufacturing facility to the customer. Distribution might involve multiple distribution points. For example, the product may be moved by the manufacturer from the manufacturing facility to a warehouse. From there, an outside trucking company may move the product to a rail or airport terminal. After the rail or air journey, another truck may deliver the product to the customer.

Overall Planning & Control

The last operation that is intrinsic to the manufacturing process is overall planning and control. Overall planning and control is listed last not because it is the least important factor, but because it includes the previous seven operations. Overall planning and control constitutes the master plan for controlling all the manufacturing systems. Frequently, the computerized mechanism for creating and managing the overall plan is achieved by utilizing a system that is labeled as one of the following:

  • Enterprise Resource Planning (ERP)
  • Manufacturing Resource Planning (MRPII).

Enterprise Resource Planning (ERP)

An ERP system integrates information from all the departments in the manufacturing company and is used by all the departments ("Enterprise resource planning," 2007).

Manufacturing Resource Planning (MRPII)

MRPII is a system for planning, controlling, and integrating all the resources associated with manufacturing, including finance and distribution (Ralston, 1996). MRPII evolved from Material Requirements Planning (MRP), a system for planning all the material requirements in a company (Ralston, 1996).

Control of Manufacturing Systems: Two Crucial Elements

The control of manufacturing systems depends upon two crucial elements:

  • Good Communication
  • Effective Tools.

Good Communication

Good communication is the first crucial element for the control of manufacturing systems. We read and hear so much about the necessity for good communication in professional and personal situations that the phrase begins to sound trite. However, good communication within and across the departments of a company is absolutely essential to any strategy for effectively controlling manufacturing systems. So, what exactly are the characteristics of "good communication" in this scenario? Good communication will exhibit the following three characteristics:

  • Transparency
  • Customer Information Exchange
  • Suppliers Partnerships.

Transparency

Transparency is the first characteristic of good communication. The goals, strategies, and methods of individual departments and the company as a whole need to be established and clearly communicated in writing to all employees who affect or are affected by the manufacturing systems. Any changes will be communicated as soon as possible and employees need to know who to contact quickly for questions or clarification. For example, the sales team needs to be notified immediately if there will be a delay in production that will affect delivery dates to current or potential customers.

Customer Information Exchange

Customer information exchange is the second characteristic of good communication. Relevant information will flow continuously between the manufacturer and customers. Manufacturers who institute a mechanism whereby customers are able to check on orders, initiate queries, or report problems will reap the double benefit of cultivating better customer relationships, while also maintaining better control of manufacturing systems.

Supplier Partnerships

Supplier partnerships constitute the last characteristic of good communication. Relevant information will flow continuously between the manufacturer and suppliers. Manufacturers can encourage suppliers to be part of their success by freely exchanging suggestions and information about needs and problems as soon as they arise and if possible, before they arise.

Effective Tools

Effective tools constitute the second crucial element for the control of manufacturing systems. The tools will vary in number and complexity depending upon the manufacturer's goals, budget, market base, and type and variety of products manufactured. However, the most effective tools for controlling manufacturing systems are often classified into three categories:

  • Technology
  • Lean Manufacturing Techniques
  • Training.

Technology

The first category of effective tools is technology. Technology includes computer hardware and software, and other automated devices.

Here are examples of two technology tools that are widely used for the control of manufacturing systems:

  • Flexible manufacturing system (FMS)
  • Radio frequency identification (RFID)

Flexible Manufacturing System (FMS)

A flexible manufacturing system (FMS) is “a form of flexible automation in which several machine tools are linked together by a material-handling system, and all aspects of the system are controlled by a central computer. An FMS is distinguished from an automated production line by its ability to process more than one product style simultaneously. At any moment, each machine in the system may be processing a different part type. An FMS can also cope with changes in product mix and production schedule as demand patterns for the different products made on the system change over time” (“Flexible manufacturing systems,” 2007). Although FMS is well-suited for the manufacturing of multiple products simultaneously, or products that require changes, it is not appropriate for the manufacturing of single, repetitive items because simpler, less costly methods would be capable of handling that type of production.

Radio Frequency Identification (RFID)

Radio frequency identification (RFID) is "a method of identifying unique items using radio waves. Typically, a reader communicates with a tag, which holds digital information in a microchip. But there are chipless forms of RFID tags that use material to reflect back a portion of the radio waves beamed at them" ("Glossary," 2007). The advantage of RFID is that it allows manufacturers to track parts and items through the manufacturing process. However, according to Sparkes (2006), there are security flaws in RFID chips that allow breaches through a variety of methods including cloning, viruses, and attacks on encryption.

Lean Manufacturing Techniques

The second category of effective tools is lean manufacturing techniques. Lean manufacturing refers to an ongoing, systematic effort to eliminate the sources of waste in a production process (Mark, 2007).

Two of the most prevalent lean manufacturing techniques are strategies that were perfected by the Japanese:

  • Just-in-time (JIT)

• Kanban

Just-in-time (JIT)

In a JIT manufacturing strategy, production and delivery only take place as products are needed. Toyota Motor Company is generally considered to have spearheaded modern lean manufacturing by implementing the just-in-time (JIT) inventory system on a full-scale basis in 1938 ("Company history," 2007).

Kanban

Kanban is an integral part of the JIT production process; it is an information tool that specifies exactly which parts or items are needed during the production process and exactly when they are needed.

Lean manufacturing techniques are effective tools for controlling manufacturing systems because they depend upon careful planning and oversight of inventory and production operations.

Training

The last category of effective tools is training. The initial and ongoing training of employees in operations and goals is of course critical to any manufacturing operation. However, the cross-training of employees on more than one machine, process, or product, goes a step further: It improves the control of manufacturing systems by increasing employee versatility and usefulness and limiting their potential for downtime. For example, cross-training allows the flexibility of easily replacing employees who are on vacation or of using them to help with other processes during a crunch or emergency. Also, training employees to broaden their skills improves morale by lessening the potential for boredom.

Conclusion

Astute manufacturers employ a variety of methods and strategies for integrating and controlling the operations that make up their manufacturing systems, depending upon their budgets and the type and complexity of products they manufacture. At a minimum, most manufacturers will employ strategies to control inventory, quality control, and distribution; most will implement an overall control such as and ERP or MRPII system to integrate and control all their operations.

Terms & Concepts

Enterprise Resource Planning (ERP): "An integrated information system that serves all departments within an enterprise. Evolving out of the manufacturing industry, ERP implies the use of packaged software rather than proprietary software written by or for one customer. ERP modules may be able to interface with an organization's own software with varying degrees of effort, and, depending on the software, ERP modules may be alterable via the vendor's proprietary tools as well as proprietary or standard programming languages. An ERP system can include software for manufacturing, order entry, accounts receivable and payable, general ledger, purchasing, warehousing, transportation and human resources. The major ERP vendors are SAP, PeopleSoft, Oracle, Baan and J.D. Edwards. Lawson Software specializes in back-end processing that integrates with another vendor's manufacturing system" ("Enterprise resource planning," 2007, ¶1).

Flexible Manufacturing System (FMS): "A form of automation in which several machine tools are linked together by a material-handling system, and all aspects of the system are controlled by a central computer. A FMS has the ability to process more than one product style simultaneously. It can also cope with changes in product mix and production schedule as demand patterns for the different products made on the system change over time. New product styles can be introduced into production with an FMS, so long as they fall within the range of products that the system is designed to process. The components of an FMS are processing machines, which are usually computerized numerical control machine tools that perform machining operations, although other types of automated workstations such as inspection stations are also possible, a material-handling system, such as a conveyor system, which is capable of delivering work parts to any machine in the FMS, and a central computer system that is responsible for communicating numerical control part programs to each machine and for coordinating the activities of the machines and the material-handling system. In addition, a fourth component of an FMS is human labour. Although the flexible manufacturing system represents a high level of production automation, people are still needed to manage the system, load and unload parts, change tools, and maintain and repair the equipment" ("Flexible manufacturing systems," 2007).

Just-in-time (JIT): A manufacturing strategy wherein production and delivery only take place as products are needed. JIT can refer to parts or items that are supplied to the manufacturer for manufacturing a product, or to delivery of the final product to the customer.

Kanban: "A card, labeled container, computer order, or other device used to signal that more products or parts are needed from the previous process step. The kanban contain information on the exact product or component specifications that are needed for the subsequent process step. Kanban are used to control work-in-progress (WIP), production, and inventory flow. Different types of kanban exist including: Supplier kanban, which indicate orders given to outside parts suppliers when parts are needed for assembly lines; in-factory kanban, which are used between processes in a factory; and production kanban, which indicate operating instructions for processes within a line" ("Lean manufacturing and the environment," 2006).

Lean Manufacturing: An ongoing, systematic effort to eliminate the sources of waste in a production process.

Manufacture: To make a product from raw materials by hand or by machine (Merriam-Webster's collegiate dictionary, 2000).

Material Requirements Planning (MRP): A system for planning all the material requirements in a company (Ralston, 1996).

Manufacturing Resource Planning (MRPII): Evolved from MRP, a system for planning, controlling, and integrating all the resources associated with manufacturing, including finance and distribution (Ralston, 1996).

Radio Frequency Identification (RFID): "A method of identifying unique items using radio waves. Typically, a reader communicates with a tag, which holds digital information in a microchip. But there are chipless forms of RFID tags that use material to reflect back a portion of the radio waves beamed at them" ("Glossary," 2007).

RFID Tag: "A microchip attached to an antenna that is packaged in a way that allows it to be applied to an object. The RFID tag picks up signals from and sends signals to a reader. The tag contains a unique serial number, but may have other information, such as a customers' account number. Tags come in many forms, such as smart labels that can have a barcode printed on it, or the tag can simply be mounted inside a carton or embedded in plastic" ("Glossary," 2007).

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Suggested Reading

Chen, C.C., Yeh, T.M., & Yang, C.C. (2006). The establishment of project-oriented and cost-based NPD performance evaluation. Human Systems Management, 25, 185-196. Retrieved August 19, 2007, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=22420726&site=ehost-live

Henry, L.C. (1998). Applying world class manufacturing to make-to-order companies: Problems and solutions. International Journal of Operations & Production Management, 18(11/12), 1086-1100. Retrieved August 17, 2007, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=1388971&site=ehost-live

Lee, S.M., Harrison, R., & West, A.A. (2005). A component-based control system for agile manufacturing. Proceedings of the Institution of Mechanical Engineers — Part B — Engineering Manufacture, 219, 123-135. Retrieved August 17, 2007, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=15683658&site=ehost-live

Oakham, M. (2007). Taking control. Engineer, 293(7716), 35-36. Retrieved July 23, 2007, from EBSCO Online Database Business Source Complete. http://search.ebscohost.com/login.aspx?direct=true&db=bth&AN=24103962&site=ehost-live

Essay by Sue Ann Connaughton, MLS

Sue Ann Connaughton is a freelance writer and researcher. Formerly, she was the Manager of Intellectual Capital & Research at Silver Oak Solutions, a spend management solutions consulting firm that was acquired by CGI in 2005. Ms. Connaughton holds a Bachelor of Arts in English from Salem State College, a Master of Education from Boston University, and a Master of Library & Information Science from Florida State University.