The 18th century manufacturing enterprises face increasingly fierce international competition, to win the market, winning users must comprehensively improve the T, Q, C, S, E of enterprises. Many companies enhance management by implementing MRPII / ERP. However, the upper production plan management is getting bigger and larger, obviously
Feel the plan to keep up. In the face of the harsh requirements of the customer, in the face of more products, the continuous adjustment of the order, the company decision makers recognize that the planned formulation is dependent on the state of the market and the actual operation, and cannot be fully material And stock returns to control production. At the same time, MRPII / ERP software is mainly for resource programs. These systems typically handle things that have happened yesterday (historical analysis), and can also expect and handle events that will happen tomorrow, but the incidents that are happening today are often left. Unregulated gap. The traditional production site management is just a black box, which can't meet the complex and variable competition needs today. Therefore, how to transpareize this black box to find any problems that affect product quality and cost, improve the real-time and flexibility of the plan, and improve the operational efficiency of the production line has become a concern for each company.
Manufacturing Execution System (MES) can fill this gap. MES is an executive layer between the plan and the workshop operation control system SFC, mainly responsible for production management and scheduling execution. It improves manufacturing competitiveness by controlling all factory resources including materials, equipment, personnel, process instructions, and facilities, providing a systematically integrating functions such as quality control, document management, production scheduling on a unified platform. . Thereby realizing the real-time ERP / MES / SFC system. MES is a new concept proposed by the American Management Direct 90s. Advanced Manufacturing Research AMR (Advanced Manufacturing Research), through the survey of large numbers, existing enterprise production management systems generally managed by ERP / MRPII, represented by SCADA, HMI (HUMAN MACHINE INTEFACE). Production process monitoring software and to achieve operational process automation, support enterprise-integrated MES software group consisting. According to the results of the survey, AMR proposed in 1992 (Figure 1). Since MES emphasizes control and coordination, it is not only a good plan system, but also enables the implementation of the implementation system. Therefore, in just a few years, MES quickly promoted in foreign countries, and brought huge economic benefits to enterprises. The company realizes that only the data information is taken out from the product level (basic automation level), through the operation control level, delivery management level, through continuous information flow, to achieve enterprise information, enabled enterprises to be unbeaten in increasing competition place.
As the company's production model gradually advances to agile manufacturing, the company's business process restructuring (BPR) is implemented, the isomerization of corporate environment, and the establishment of the company's dynamic alliance, the traditional MES is solved. The solution is difficult to adapt to agile manufacturing requirements, but aggregated Mes not only cost reasonable and more adaptability, reconfigurable, integratable, therefore, many organizations and research abroad Institutions began to study Mes for agile manufacturing. However, the study of MES concepts and applications in China is not much, and there is no mature software product. With the continuous promotion of enterprise computer applications, corporate information application levels are gradually improved, and companies are increasingly needed to manage information systems for workshop execution. Therefore, how to understand MES connotation, grasp the development trend, develop and apply MES in my country's enterprises, and reduce business competitiveness, narrowing the gap between enterprises and developed countries is imminent, and will be deeply promoted by corporate informationization. need.
1, manufacturing execution system (MES)
1) Mes Connotation MES's demand is produced by changes in production in more than a decade, so it has a short history than MIS, MRP, CAD / CAM, but people have a very good research and application Rapid, Mesa International (MES International Federation) is a trade franchise in promoting MES thinking and product as a tenet, in order to help its membership organizations have developed a series of research, analysis and development plans in the business world promotion MES. The MES is the following definitions of MES as follows: MES optimizes management through information transfer to achieve the entire production process that meets the product from orders. When a real-time event occurs in a factory, MES can respond, report, and guide them with current accurate data. This rapid response to state changes allows MES to reduce no added value within the company, effectively guide the production process of the factory, so that it can improve the timely delivery capacity of the factory, improve the circulation performance of materials, and improve Production return rate. MES also provides critical task information about product behavior in the interior of the enterprise and the entire product supply chain through two-way direct communications.
It can be seen from the above definition that MES is to emphasize the optimization of the entire production process, which requires a large number of real-time data in the production process, and dealing with real-time events. At the same time, the two-way communication capability is maintained with the plan layer and the control layer, and the corresponding data is received from the upper and lower layers and feedback processing results and production instructions. Therefore, MES is different from the traditional workshop controller characterized by the production management and auxiliary material stream in the form of dispatched work orders, and is also different from the unit controller that is mainly focused on the operation and equipment scheduling, but should use MES as a one. The production mode is integrated with the planning and progress arrangement, tracking, monitoring and control, material flow, quality management, control of material, and computer integrated manufacturing interface (CIM) to finally implement the manufacturing automation strategy. Figure 2 reflects the data flow map and the status of MES in enterprise production management.
Figure 2 MES data flow map in the enterprise
2) MES framework model
