Advanced Computer Integrated Manufacturing - Essay Example

Advanced Computer Integrated Manufacturing WHAT IS COMPUTER INTEGRATED MANUFACTURING (CIM) Computer integrated manufacturing (CIM) is a system in which individual engineering, production and marketing are organized into a computer-integrated system. The computer is linked with all the procedural steps such as design, analysis, planning, purchasing, cost accounting, inventory control and distribution along with materials handling and management. CIM may also be viewed as a tool which links different computer related technologies, such as computer-aided manufacturing (CAM), computer-aided design (CAD), numerically controlled machine tools (NCMT), automatic storage and retrieval systems (AS/RS), flexible manufacturing systems (FMS), robotics and other computer-based manufacturing technology. CIM is also known as integrated computer aided manufacturing (ICAM). Different definitions of CIM exist according to expertise of individuals in varied fields. For example, Johansen (Johansen, Karmarkar, Nanda, Seidmann, 1995) defines CIM to include the following: 1. "Factory communication hardware and software. 2. Data management, including collection, storage, and retrieval. 3. Applications software and hardware, including material planning and control, quality systems, inspection and vision, computer-aided design/computer-aided manufacturing (CAD/CAM), and computer aided process planning/computer-aided engineering (CAPP/CAE)." Weston (1994) suggests that CIM comprises of three different dimensions: 1. "Engineering scope involving CAD/CAM and CAPP activities. 2. Network and systems dimension. 3. Continuous improvement dimension including fields such as MRP II, TQM, JIT and Theory of Constraints (TOC)." Another scholar described CIM as an "integration tool which uses information and automation hardware and software for production control and management" (Gould, 1989). A different perspective of CIM is that it is a "management technology that makes feasible the fully-automated factory-of-the-future" (Zachary, Volume 25). GROUP TECHNOLOGY (GT) AND CELLULAR MANUFACTURING SYSTEM (CMS) GT is a manufacturing philosophy in which the parts having similarities are grouped together to achieve higher level of integration between the design and manufacturing functions of a firm (Girdhar). The aim is to reduce work and improve performance by reducing lead times. GT emphasizes the principle that many problems are similar to each other and by grouping similar problems together; we can find a single solution to a set of problems. The group of similar problems is known as part family and the group of machineries used to process an individual part family is known as machine cell. This type of manufacturing in which a part family is produced by a machine cell is known as 'Cellular Manufacturing'. Group Technology can: Enable Cellular Manufacturing Reduce Engineering Cost Accelerate Product Development Improve Costing Accuracy Simplify Process Planning Reduce Tooling Cost Simplify Purchasing Help With Value Stream Mapping BENEFITS OF GT GT benefits manufacturing in many ways. It reduces the number and variety of parts. Computer Aided Process Planning (CAPP) is an important tool for this. It uses the coded similarities to plan consistently, standardize and accurately estimate costs. It then assigns the part to a GT manufacturing cell. It also reduces throughput time and Work-In-Process. They simplify schedules, reduce transportation and ease supervision. Some of the more dramatic and tangible savings come from improved setups and tooling cost. Setup time reductions bring smaller lot sizes and smaller queues which mean faster throughput, shorter lead times and decreased inventory. Moreover, GT sometimes eliminates the need for expensive NC equipment. Combined with NC, GT simplifies programming, fixturing and tooling. FLEXIBLE MANUFACTURING SYSTEM (FMS) "A system that consists of numerous programmable machine tools connected by an automated material handling system" (Russell). FMS has following layouts: Progressive Layout: Best for producing a variety of parts Closed Loop Layout: Parts can skip stations for flexibility Used for large part sizes Best for long process times Ladder Layout: Parts can be sent to any machine in any sequence Parts not limited to particular part families Open Field Layout: Most complex FMS layout Includes several support stations. INTEGRATION OF FMS INDUSTRIAL ROBOTS Robots are "programmable manipulators that can tolerate hostile environments, work much longer hours than humans and can perform redundant jobs more consistently (Fosters). Common uses of robots include the following: Loading and unloading Spray painting Welding Material handling Inspection Machine Assembly AUTOMATED HANDLING SYSTEM (AHS) AHS is the use of computers to control the moving and positioning of materials in a warehouse or factory. Automated handling may involve the use of robots. AUTOMATED STORAGE/ RETRIEVABLE SYSTEM (AS/RS) An automated storage and retrieval system (ASRS or AS/RS) consists of a variety of computer-controlled methods for automatically placing and retrieving loads from specific storage locations. AS/RS are typically used in applications where there is a very high volume of loads being moved into and out of storage where storage density is important because of space constraints. Automated storage and retrieval systems do require considerable investments of a company's resources. The cost of purchasing and implementing an effective automated storage/retrieval system is significant as well, encompassing everything from pre-purchases analysis of supply chain and inventory management needs to the actual purchase price of AS/RS equipment and software. In addition, experts in the use and maintenance of AS/RS systems note that companies often experience significant ongoing costs for maintenance and updating of various subsystems. These capital expenses can tempt some business owners to cut financial corners, buying "bargain" systems that are ill-equipped for extensive, long-term use. In many cases, such decisions can end up costing far more in the long run. "A long and reliable service life [for an AS/RS system] begins with procurement, not maintenance" (Wigington). Light-duty storage systems are particularly vulnerable by failing to deliver well-engineered equipment and software. These systems require a high level of upkeep and experience a sticky, entangled web of mechanical, electrical, and software problems. When such disruptions occur, the impact can be devastating to small and mid-sized businesses. As a result, businesses are urged to examine the long-term implications of their choices when they incorporate an automated storage and retrieval system into their operations. References Johansen, J., Karmarkar, U., Nanda, D., Seidmann, A., "Computer Integrated Manufacturing: Empirical Implications for Industrial Information Systems," Journal of Management Information Systems, Volume 12, Issue 2 (Fall 1995) pp. 59-70. Weston, F.C., "Three Dimensions of CIM," Production and Inventory Management Journal," Volume 35, Issue 1, First Quarter, (1994) pp. 59-64. Gould, L., "CIM is Easier than Ever," Systems Integration, (December, 1989) pp: 54-59. Zachary, W., Richman, E., "Building an Operations Management Foundation That Will Last," IIE Solutions, Volume 25, Issue 8; pp: 39-46. Girdhar, Anupan. Expansion of group technology par coding based on functionality. Read More