Design of manufacturing execution system (MES) in assembly shop
The concept of ystem (ManufacturingE xecutionS, MES) was formed in the late 1980s, and gradually improved and developed rapidly in 90s. The United States advanced manufacturing research institutions AMR MES will be defined as: "management information system for workshop layer between the industrial control plan management system and the bottom is located on the top of it, for the implementation of the plan and track all resources (people, equipment and materials) the current state of. Based on the design and development of the MES system of the large automobile transmission assembly line, this paper introduces the architecture, function structure and related technologies of the MES system.
Assembly line configuration analysis
The assembly workshop equipment system mainly includes the following four categories: assembly line, assembly line material rack, material warehouse and feeding system.
According to the design target of the system determined by the enterprise, tracking the current development trend of technology, assembly workshop construction of a high degree of automation, the relevant equipment selection assembly production line, advanced intelligent rack, intelligent warehouse and intelligent feeding trolley, and the manufacturing execution system combine the various types of equipment and system integration, height to achieve the production process automation.
1 assembly line
Including car assembly line, assembly tools and equipment, assembly car with new rail guided vehicle (Rail Guided, Vehicles, RGV) and AGV (Automatic Guided Vehicles, AGV), to replace the conveyor system configuration is relatively complex and poor maneuverability.
2 assembly line rack
The use of intelligent material rack management, to achieve the main parts of each station on the material, materials, storage, automatic counting and other functions, in order to facilitate the application and distribution of materials, improve the level of automation.
3 parts warehouse
Storage of spare parts of the yard are: the main warehouse, parts assembly workshop, self-made parts warehouse. Among them, the main warehouse using intelligent three-dimensional warehouse, automatic discharge.
4 material distribution system
Laser guided car (Laser Guided Vehicles, LGV) for material distribution. The laser guided mode and electromagnetic, optics, inertial guidance mode, stop has high precision, strong autonomy, high intelligence, adaptability and flexibility, the path of expansion and change is more convenient, low installation cost, high reliability.
Two assembly production logistics, data flow analysis
1 main logistics system
In order to design a reasonable function structure of MES system, it is necessary to analyze the change of assembly workshop logistics:
1) develop assembly production plan: the planning department to make the assembly plan according to the market demand.
2) warehouse stock, stock: to ensure the implementation of assembly planning, sourcing and purchasing parts library.
3 warehouse material: according to assembly production tasks, from the intelligent warehouse in a certain rhythm to the distribution center.
4) car feeding: transport material LGV car parts from the distribution center to the corresponding assembly station, feeding rack.
5) assembly: each station according to the assembly process will be the corresponding parts assembly.
6) offline storage: assembly and testing of finished product assembly line, into the product cache.
7) sales out of the warehouse: according to production orders, will be related to the finished product shipped out of the production workshop.
2. The main data processing flow and the corresponding data processing flow of the system are shown in Figure 1
Three, MES system software function design
MES is used to assist the production manager to collect the field data, and to control the process of manufacturing process. It is a tool to improve the manufacturing process and improve the production efficiency.
1 basic principles of system design
In order to improve the design and development of MES system, the following basic principles:
1, in order to meet the needs of the user as the goal: the system design, fully understand the user needs, grasp the system business processes and resources;
2) to establish a global perspective, local adaptation of the overall, focusing on the coordination of the system;
3) pay attention to system security and reliability;
4) pay attention to the scalability of the system;
5) do not blindly pursue new technologies, try to be practical: a good system should first be an available system;
6 user interface is friendly, intuitive and clear, easy to operate.
2 software function module
MES has the following major functions, and the relationship between the enterprise's other systems as shown in figure 2.
3 software features
1 assembly planning management: including the assembly of the annual, monthly, three day rolling and assembly planning and adjustment of the day assembly; assembly rolling on the three day, the day of assembly planning, execution and tracking the progress of the plan. Assembly planning and ERP system interface.
2 assembly process management: including the assembly line production processes, assembly parts, assembly time management, as well as the assembly process improvement, the station assembly process browsing man-machine interface.
3) material distribution management: according to the assembly plan of the assembly day, the station intelligent material rack records the reasonable distribution of the material of each work station, and provides the material consumption and distribution batch tracking.
4 (quality) online management: according to the quality standards, the data collected automatically judge, exceed the situation alarm, to achieve the quality of online control and statistical analysis.
5) equipment maintenance management: assembly workshop equipment operation and maintenance records management; including the equipment fault information, equipment routine maintenance project and equipment routine maintenance (maintenance, maintenance, inspection and lubrication plan management) and generates maintenance requisitions and spare parts list.
6) Workshop Evaluation and management: according to the information of the assembly tracking process