Definition
A cell is a group of workstations, machines or equipment arranged such that a product can be processed progressively from one workstation to another without having to wait for a batch to be completed or requiring additional handling between operations. Cells may be dedicated to a process, a sub-component, or an entire product. Cells are conducive to single-piece and one-touch manufacturing methods and are often found as part of lean manufacturing applications. Cells may be designed for the office as well as the factory.
Group technology or families-of-parts concepts are often used in cellular design. Group technology is the process of studying a large population of different workpieces and then dividing them into groups of items having similar characteristics. The process may be executed with the aid of a computer, and has been used to divide parts into groups for use with CAD/CAM processing. Family of parts is the process of grouping workpieces into logical families so that they can be produced by the same group of machines, tooling, and people with only minor changes on procedure or setup.
Both group technology and family of parts processes are used in designing fast factories. When parts are grouped together, using similar geometries makes CAD/CAM faster since electronic configurations developed previously can be used for new similar parts to cut time out of design engineering. In production, setups and changeovers are faster because the same tools and fixtures can be used for similar parts. With group technology the workpieces and machining operations have to be classified. Once coded into classifications, processing information can be retrieved quickly.
In a cell, parts are produced by successive operations. By separating them into families according to size and shape (small round, large rectangular), so that similar parts can be produced across the same machines. A cell may also be designed to be a single flexible multi-operation machine, such as a machining center.
A cell is configured normally for speed and minimal material handling and can reap substantial benefits in cost saving, time compression, and inventory reduction. In families-of-parts applications, a component may or may not move across all pieces of equipment. One part may be processed on all machines, but the next part may be processed on one or two. A cell may include sub-assembly or assembly processes depending on the product. In contrast a sub-assembly operation or assembly can be configured in a cellular arrangement.
Cellular configurations can be in several forms: straight line, u-shape, but equipment contained with the cell, or workstations, are normally configured in closely promimity to compress time and space. Quick changeover from one product to the next is paramount for inducing cell velocity. Material handling within a cell may be by robot, conveyor, or it can be manual. When robotic applications or automated conveyance are used, a cell supervisory computer is requred to control movement between the individual pieces of equipment and the automated conveyance.
The Issues
Cells are not new as one might believe. However with the trend in the U.S. for higher productivity and short manufacturing lead times, cells have become popular. Some companies assign certain machines located in their original places across the factory from each other to a "virtual cell" and anoint it cellular manufacturing. This is as practical as flying from New York to Cincinnati to Chicago to Denver to San Francisco and calling it a direct flight.
Other companies simply move equipment around in a closer proximity and call it a cell, which is the same as moving furniture around a room. The reason for this is that more often that not, cellular solutions demand a level of capitalization that managers may not be willing to commit. However, if the man-to-machine ratio remains the same, then all you have accomplished is closing the distance for material handling.
Just like anything else, cellular manufacturing is no panacea, nor should it be embraced as a religion. It is an operational strategy that, if implemented properly, will provide a new dimension to competing: quickly introducing new customerized high quality products and delivering them with unprecedented lead times, swift decisions, and manufacturing products with high velocity.
Pragmatic Applications
Cells can have a substantial impact on a company's productivity and throughput. Flexible cells can be very effective when applied in an environment with a product characteristic of low volume and wide breadth. However very careful analysis is essential since the solutions may require a high level of capitalization.
Our Approach: Tools from a Toolchest
Rockford Consulting Group applies concepts and technologies as the situation warrants, that will result in the ultimate benefit to our clients. We treat strategies, technologies, and methodologies as tools in a toolchest, and use them when they offer practical solutions and achievable results. We believe that each client situation is unique, with its own unique set of solutions. (Please see our cellular manufacturing consulting services Cellular Manufacturing Consulting Services)
Why Us?
Rockford Consulting Group can provide long-term assistance to many companies in a variety of industries. The firm has a cadre of the best supply chain consultants in the world today, providing high quality professionalism through the use of experience and innovation.
We subscribe to the Institute of Management Consultants Code of Professional Conduct. All consultants engaged on projects adhere to its principles. Whenever possible we will use consultants certified in their particular specialty area. Certification assures that consultants have substantial prior experience in their specialty, and their competencies have been tested by the IMC, and verified by a number of clients. This assures our clients that we are assigning the highest qualified consultants in the profession.
We provide technical expertise, team facilitation, leadership, and direction in deciding how you will meet the challenge. We refer you to our Qualification Statement for further details on our background, areas of specialization, concepts and technologies applied, staffing, operating policy, approach, companies and industries served, case studies and references. Equally as important, we train our clients to sustain new methods of manufacturing and the consequential benefits over time. Your company will benefit directly from this training.
We have achieved an efficiency in our approach to assignments that allows us to provide high quality technical and managerial advice in a much shorter amount of time than could be accomplished years ago. We are able to do this because of the extensive consulting experience that each of our specialists has.
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