Abstract : Based on a detailed analysis of the characteristics of automotive mold production and the current status of information technology application, this paper proposes an architecture for a Manufacturing Execution System (MES) for the automotive mold industry. The functions of each module are elaborated, and key technologies and development trends of MES are further discussed. Keywords : MES, Mold Industry Architecture 1 Introduction With increasingly fierce competition in the manufacturing industry, many enterprises have implemented MRP II/ERP systems to strengthen production management. However, due to a lack of sufficient shop floor control information, they cannot meet the requirements of the randomness and dynamism of production, and cannot achieve close connection with the shop floor environment, thus failing to effectively guide the execution of shop floor production plans. With the continuous promotion of enterprise information technology applications and the gradual improvement of enterprise information technology application levels, enterprises increasingly need management information systems at the shop floor execution level. Currently, most automotive mold enterprises rely mainly on manual management for shop floor production, with the planning and control layers disconnected, unable to adapt to the dynamic changes in the production process, greatly restricting further improvement in production management. The emergence of Manufacturing Execution System (MES) fills the gap in shop floor management. MES takes job scheduling as its core and aims to reduce production costs and improve production efficiency. It collects real-time information in the production process and processes real-time events in a timely manner. At the same time, it maintains two-way communication with the planning and control layers, receives relevant information from the upper and lower layers and feeds back processing results and production instructions, thereby optimizing the entire production process. This paper proposes the construction and application of MES for automobile molds based on the production characteristics and information management status of the automobile mold industry. 2 Characteristics of automobile mold production and current status of information application 2.1 Characteristics of automobile mold production As an important process equipment in the automobile industry, molds are the process foundation of automobile manufacturing. Due to the complexity of the products themselves and their typical single-piece order production mode, their production is different from that of general products. The characteristics are as follows: (1) Order-oriented production. Due to the large changes in order specifications, quantity and delivery time, each product has its own particularity. From product ordering decision to the entire manufacturing process, each mold has a certain degree of independence. Enterprises must organize production according to orders. (2) Production progress is difficult to control. Since the products are produced individually, almost every product needs to be redesigned, reprocessed, and technically prepared. Therefore, it is often impossible to keep track of changes in production progress in a timely manner and it is difficult to control the entire production process. (3) The plans are often changeable. Due to the wide variety of products, there are many uncertain factors affecting the production process. Urgent orders, equipment failures, and rework and repair of parts often occur, which makes the plans change frequently and even the plans cannot keep up with the changes and are out of sync with the actual production. (4) Production management is difficult. The mold manufacturing process is complex and there are many uncertain factors in the production process. It is impossible to ensure the coordination of the entire production process by relying on experience scheduling. The process control is difficult and the management is difficult. 2.2 Current Status of Information Application in the Automotive Mold Industry At present, the information construction of my country's automotive mold industry has just started. The level of networking and information development is still relatively low. After detailed research, the following problems were found: (1) Workshop management mainly relies on manual labor, which cannot achieve effective management of massive data in the production process. It is difficult to ensure that the information required by each production activity is accurate and consistent, and it is difficult to respond to dynamic changes in production in a timely and rapid manner. (2) Most automotive mold enterprises have a low degree of networking and prominent "information silos". Data from various departments cannot be shared in real time, which affects the consistency and accuracy of enterprise data and seriously hinders the development efficiency of mold products. (3) The mold production process lacks effective monitoring, making it impossible to realize timely feedback of manufacturing process information, making it difficult to grasp production progress and production capacity in a timely manner, and making it difficult to effectively track work-in-process. The existence of the above problems is not conducive to the integration and sharing of workshop production process information, seriously hindering the improvement of the enterprise's informatization development level, thus affecting the further improvement of the enterprise's production efficiency and competitiveness. 3 MES for the automotive mold industry 3.1 Architecture Based on large relational database technology, using object-oriented technology and soft bus technology, an open and agile manufacturing execution system is established to realize the monitoring and control of production information and the optimized management of the production process. Figure 1 shows the architecture of automotive mold MES. [align=center] Figure 1 Automotive mold MES architecture[/align] The top planning layer is the MRPⅡ/ERP system, which is responsible for managing various production resources in the enterprise, formulating plant-level production plans, etc., and is mainly responsible for the planning and production decisions of enterprise activities. The middle layer is the MES execution layer, which is mainly responsible for the execution and control of production plans. The production control layer includes computer control systems such as DCS (Distributed Control System), PLC (Programmable Logic Controller) and DNC (Distributed Numerical Control Equipment), which are mainly used to control the production process and equipment. MES provides a way to systematically integrate planning, material tracking, production scheduling and other functions on a unified platform. By integrating with the planning layer's management system (ERP) and the underlying control system, planning, production and control are closely linked, thus establishing a communication bridge and link between the planning layer and the control layer. 3.2 Functions of each module The MES system mainly includes planning and scheduling, workstation electronic Kanban, material tracking, production cost management, production statistics and analysis and system management. The functions of each module are as follows: (1) Planning and scheduling module The planning and scheduling module is the core of the automotive mold MES. Based on effective integration with other MES modules and the ERP system, the processing sequence of all workpieces on the equipment and the start and end times of each process of the equipment are determined through limited capacity scheduling. When there are urgent orders, equipment failures, rework and repairs, or production delays on the production site, reasonable optimization techniques and methods are used to schedule production, adjust the work plan and scheduling resources to adapt to the actual production conditions, thereby improving the continuity of the production process and ensuring efficient production operation. (2) Workstation Electronic Kanban Module The electronic kanban is a visual kanban for workshop operation stations built on the basis of computer networks. The workstation electronic kanban module presents the production task list and related process information on the kanban of the operation station in a timely manner through the workshop computer network, issues production instructions to the operators, thereby realizing network dispatching, and providing them with operation guidance information such as operating procedures, equipment, tools, materials, and auxiliary materials. (3) Material Tracking Module The material tracking module uses barcode technology to track the entire mold production process, collects information on the flow of work-in-process, material consumption, product rework and repair, and scrap in real time, obtains detailed historical records of each mold, thereby making the product production process transparent and realizing the traceability of the production process of each mold. (4) The production cost management module classifies, collects, and allocates costs according to different activities using the dynamic activity costing method. It correctly distinguishes between variable costs and fixed costs, controllable costs and uncontrollable costs. Based on the processing and assembly process described in the product BOM and combined with real-time data collection information, it accumulates costs layer by layer from the lower level to the higher level to calculate the workshop production cost. It reflects the actual process of dynamic value-added of products and can realize accurate cost statistics in real time. (5) The production statistics and analysis module will realize the statistics and analysis of information such as production plan, production execution progress, quality inspection, and resource utilization rate on the basis of effective integration with other modules of MES and ERP system. It will provide support for better optimization of production process, improvement of product quality, and maintenance of optimal production status. (6) The system management module manages system users by role, manages their departments, positions, personnel, permissions and other information, saves system login records, ensures the security and confidentiality of product information, provides system data backup and data recovery functions, and ensures the safe operation of the system. 3.3 Key Technologies MES is the key to the informatization construction of the automotive mold industry workshop. Whether it is successfully developed and applied is related to the success or failure of the informatization construction of automotive mold enterprises. Its key technologies mainly include: (1) Job sequencing optimization technology Job sequencing optimization is the core function of production planning and job scheduling, which determines the best processing order of workpieces on equipment or work centers. The priority scheduling rule method of heuristic algorithm is used to optimize job sequencing. The predefined priority rules are used as heuristic conditions to select the highest priority job from the waiting jobs for processing. In setting the processing priority, the delivery date, parts and equipment are considered comprehensively. The priority of mold is set according to the order of delivery date; the priority of parts is set manually according to the actual situation and experience; and the priority of equipment is set according to the principle of the least number of scheduled tasks. This method is easy to implement, has low computational complexity, and the processing priority can be adjusted manually, so that the scheduled job order is more in line with the actual production. (2) Barcode data acquisition technology Barcode data acquisition technology is a comprehensive science and technology based on computer technology, optoelectronic technology and communication technology. It is an important method and means of information identification and acquisition. It has the advantages of high speed, high accuracy, simple operation and large amount of information collected. Using barcode automatic identification technology to collect and track logistics information in the production process, the entire production process can be monitored in real time, and a large amount of data in production can be recorded and processed to realize data traceability, reverse lookup, reporting and other functions, thereby improving management efficiency and quality. (3) System integration technology In order to realize the sharing and exchange of product information in heterogeneous systems, XML (Extensible Markup Language) neutral files are used to realize the integration of MES with ERP system and control system. XML technology has the characteristics of openness and easy extensibility, and can exchange and share data between different programs. The information integrated between MES and ERP system includes production plan, BOM information, process information and material information. This integration method can not only improve the correctness and consistency of data transmission between systems, but also improve the information feedback speed, which is conducive to information sharing. 4 MES development trend MES is an information management system oriented to the workshop level. Its application has brought huge economic benefits to enterprises. With the development of information technology and the competitive needs of manufacturing enterprises, enterprises have put forward higher requirements for MES application technology. Meeting the requirements of integrability, adaptability, openness and collaboration is the development trend of MES. Specifically, the following aspects are reflected: (1) XML technology is used to solve the data heterogeneity problem between MES, ERP and the underlying control system, making the system more open, integrable and more closely integrated; (2) Based on the research on automotive mold MES software products, a general solution for discrete industries is established to adapt to various specific practical needs of discrete industries; (3) Management technologies and concepts such as data mining, knowledge management, optimization technology and lean thinking will be widely used in MES, promoting the development of MES theory; (4) With the development of information and network technology, collaborative MES has become a research hotspot. 5 Conclusion By analyzing the characteristics of automotive mold production and the current status of information application, the system architecture and functions of the manufacturing execution system with production planning and operation scheduling as the core are proposed, and the key technologies and future development trends of the system implementation are further elaborated. Through the construction of automotive mold MES, a mechanism and platform for production information sharing are established, the digital management and control of production resources and production processes are strengthened, and a communication bridge is built between the planning layer and the control layer, thereby realizing the "integrated management and control" of production. [References] [1] Liu Dezhong, Fei Renyuan, Wu Guowei. Manufacturing Engineering Histology. Science Press, 2005. [2] Gao Xuejin, Wang Pu, et al. Research on MES for the Pharmaceutical Industry. Enterprise Informationization, 2005.