Introduction to FMS of the hottest flexible manufa

2022-08-13
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Introduction to FMS

since the 1980s, in industrialized countries, flexible 5. Accumulator: some electro-hydraulic servo experimental machines are equipped with an accumulator based manufacturing system, which has been applied practically as the first step towards factory automation. Its application successfully solves the contradiction between high automation and high flexibility in mechanical manufacturing

first, the rise of flexible automation

with the development of science and technology, human society has higher and higher requirements for the function and quality of products, the cycle of product upgrading is shorter and shorter, the complexity of products is also increased, and the traditional mass production mode is challenged. This challenge not only poses a threat to small and medium-sized enterprises, but also puzzles large and medium-sized state-owned enterprises. Because in mass production, flexibility and productivity are contradictory. As we all know, only a single variety, large batch, special equipment, stable process and high efficiency can constitute economies of scale; On the contrary, in the case of multi variety and small batch production, the specificity of the equipment is low. In the case of similar processing forms, frequent adjustment of jigs and fixtures will increase the difficulty of process stability, and the production efficiency is bound to be affected. In order to improve the flexibility and production efficiency of manufacturing industry at the same time, shorten the production cycle and reduce the cost of products on the premise of ensuring product quality, and finally make small and medium-sized batch production compete with mass production, flexible automation system came into being

since the birth of the first numerically controlled milling machine at MIT in 1954, flexible automation entered the practical stage of production in the early 1970s. For decades, from the application of single NC machine tool to machining center, flexible manufacturing unit, flexible manufacturing system and computer integrated manufacturing system, flexible automation has developed rapidly

second, the type and composition of flexible manufacturing system

the type of flexible manufacturing system

flexible manufacturing refers to a manufacturing system that can adapt to the changes of processing objects with the support of computers. Flexible manufacturing system has the following three types:

flexible manufacturing unit

flexible manufacturing unit is a processing unit composed of one or more CNC machine tools or machining centers. The unit can automatically change tools and fixtures as needed to process different workpieces. Flexible manufacturing cells are suitable for processing parts with complex shapes, simple processing procedures, long processing hours and small batches. It has large flexibility of equipment, but low flexibility of personnel and processing

flexible manufacturing system

flexible manufacturing system is a production system based on CNC machine tools or machining centers and equipped with material conveying devices. The system is automatically controlled by an electronic computer, which can meet the processing of multiple varieties without stopping the machine. Flexible manufacturing system is suitable for processing parts with complex shape, many processing procedures and large batch. Its processing and material transfer flexibility is large, but personnel flexibility is still low

flexible automatic production line

flexible automatic production line is a production line composed of multiple adjustable machine tools (mostly special machine tools) and equipped with automatic conveying devices. The production line can process parts of different specifications in large batches. The flexible automatic production line with low flexibility is close to the automatic production line for mass production in performance; The flexible automatic production line with high flexibility is close to the flexible manufacturing system for small batch and multi variety production

composition of flexible manufacturing system

as for the flexible manufacturing system of mechanical manufacturing industry, its basic components are:

automatic processing system

automatic processing system, which refers to taking group technology as the basis, putting the overall dimensions (the shape does not have to be completely consistent), the weight is roughly similar, and the materials are the same, After the experiment of parts with similar process is completed, the experimental curve can be recalled and processed on one or several CNC machine tools or special machine tools

logistics system

logistics system refers to a system composed of a variety of transportation devices, such as conveyor belt, track turntable and manipulator, to complete the supply and transmission of workpieces, cutting tools, etc. it is the main component of flexible manufacturing system

information system

information system refers to a system that collects, processes and feeds back all kinds of information required in the process of processing and transportation, and implements hierarchical control of machine tools or transportation equipment through electronic computers or other control devices (hydraulic, pneumatic devices, etc.)

software system

software system refers to an indispensable part to ensure the effective management of flexible manufacturing system with electronic computer. It includes software for design, planning, production control and system supervision. Flexible manufacturing system is suitable for medium and small batch production with annual output of 1000 ~ 100000 pieces

III. advantages and development trend of flexible manufacturing system

advantages of flexible manufacturing system

flexible manufacturing system is a system with complex technology and high automation. It organically combines microelectronics, computer and system engineering, and ideally and successfully solves the contradiction between high automation and high flexibility of mechanical manufacturing. The specific advantages are as follows

first, the equipment utilization rate is high. After a group of machine tools are programmed into the flexible manufacturing system, the output of this group of machine tools is several times higher than that of this group of machine tools in decentralized single machine operation

second, WIP decreased by about 80%

third, the production capacity is relatively stable. The automatic processing system is composed of one or more machine tools. In case of failure, it has the ability to degrade the operation, and the material transfer system also has the ability to bypass the failed machine tools by itself

fourth, high product quality. During the processing of parts, loading and unloading are completed at one time, with high processing accuracy and stable processing form

fifth, flexible operation. The inspection, card loading and maintenance of some flexible manufacturing systems can be completed in the first shift, and the second and third shifts can be normally produced unattended. In an ideal flexible manufacturing system, its monitoring system can also deal with unexpected problems in the operation process, such as tool wear and replacement, logistics congestion and dredging

sixth, the product has great adaptability. The cutting tools, fixtures and material transportation devices are adjustable, and the plane layout of the system is reasonable, which is convenient for adding or removing equipment and meets the needs of the market

the development trend of flexible manufacturing system

the development trend of flexible manufacturing system has two aspects. On the one hand, it combines with computer-aided design and manufacturing system, and uses the typical process data of the original product series to combine and design different modules to form various forms of modular flexible systems with material flow and information flow. The other is to realize the automation of the whole production process from product decision-making, product design, production to sales, especially the computer integrated manufacturing system with automatic management level. In this large system, flexible manufacturing - other formulas: can be used for vinyl, colorant, cross-linked PVDF and fep/PVDF chemical foaming additive system is only a part of it

modular flexible manufacturing system

in order to ensure the reliability and economy of the system, its main components can be standardized and modularized. The conveying module of machined parts includes induction line guide rail trolley conveying and rail trolley conveying; The tool conveying and exchange module includes a tool exchange robot and a tool box conveying mode that shares a conveying trolley with the workpiece. Using different module combinations, different forms of flexible manufacturing systems with material flow and information flow are formed to automatically complete all processing processes with different requirements. Figure 1 is the characteristic diagram of a typical modular flexible manufacturing system. It can be seen from Figure 1 that the supply mode of cutting tools and the transportation, storage and exchange mode of workpieces are the biggest factors affecting the complexity of the system

Computer Integrated Manufacturing System

according to statistics, in the 100 years from 1870 to 1970, the efficiency of processing process has increased by 2000%, while the efficiency of production management has only increased by 80%, and the efficiency of product design has only increased by about 20%. Obviously, the efficiency of the latter two has become a constraint to the further development of production. Therefore, the development of manufacturing technology cannot be limited to the automation of workshop manufacturing process, but to fully realize the automation of the whole production process from production decision-making, product design to sales. Xinda group, especially founded in 1985, is the automation of management level work. Such an integrated production system is computer integrated manufacturing system (CIMS)

The main characteristics of CIMS are integration and intelligence. Integration is the breadth of automation, which extends the space of the system to the whole process of market, product design, processing and manufacturing, inspection, sales and service for users; Intelligent automation is deepening, including not only the automation of material flow, but also the automation of information flow

Figure 2 is the model of CIMS. The decision-making level is the leading organization of the enterprise, which grasps and connects the information of all departments through the management information system. In the virtual box is the information flow of the product manufacturing process. The information source of production activities comes from the production object - product ordering. According to users' requirements for product functions, CAD (Computer Aided Design) system provides all information and data about products. Product raw data is the initial information source of enterprise production activities. Therefore, intelligent CAD system is the basis of CIMS. CAPP (Computer Aided Process Planning) system should not only prepare process procedures, design tools and fixtures, and determine man hours and process costs, but also connect with cam (Computer Aided Manufacturing) system to provide process data for CNC machine tools, production planning, job scheduling, quality management and cost accounting, and feed back information such as manufacturing possibility and cost to CAD system, The production planning and control system is the production command hub of the whole plant. In order to make the production proceed in an orderly way, we must establish a production data collection system accordingly, so as to form an information feedback system that can reflect the real situation of the production process

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