1. MES system solutions for the steel manufacturing industry
In the iron and steel industry, the five-level architecture of the information system has been generally recognized. They are the first-level basic automation system (BAS), the second-level process control system (PCS), the third-level workshop-level manufacturing execution system (MES), and the fourth-level Enterprise resource planning system (ERP), and five-level inter-enterprise management system and decision support system (DSS).
For iron and steel production enterprises, MES is responsible for the generation of production plans, the issuance of production orders, the collection of operational performance, material tracking, quality management, material management, and transportation management. Through the advanced and optimized production scheduling system, production line sequencing system, and manufacturing execution system in MES, it provides manufacturing execution solutions that can meet different production requirements for the entire steel production process. If ERP focuses on value and results, then MES focuses on the entire process of producing results.
2. Problems to be solved urgently by MES in iron and steel enterprises
In the on-site construction service, I found that the problems that iron and steel enterprises need to solve are as follows:
(1) The introduction of advanced management concepts
my country’s iron and steel industry has a history of more than 60 years since Anshan Iron and Steel was established in 1948. The iron and steel industry has formed a set of deep-rooted and effective management models. However, with the upgrading of equipment, the improvement of automation level, and the introduction of information technology, the original management mode can no longer adapt to the current stage of operation and management of the enterprise.
Iron and steel enterprises need to introduce domestic and foreign advanced management concepts suitable for iron and steel enterprises, sort out and optimize their own business processes through MES, and realize the close connection and flat management among enterprises through business process reorganization, so as to make the upstream and downstream of the supply chain an organic whole, to achieve real-time information communication and collaboration.
(2) Data collection
At present, domestic large-scale iron and steel enterprises have realized production management through MES in the main process, and the future MES market of small and medium-sized iron and steel enterprises cannot be ignored. However, the information obtained from the field found that the automation level of small and medium-sized enterprises is relatively low, and many processes do not have a secondary PCS. Repeated and complicated human input causes personnel to resist the system, which provides obstacles to the implementation of MES and achieving the expected results.
The MES system can directly grasp the real-time information of the site through data collection and reduce human operations. Part of the process can be controlled, and operators can operate on-site in the operating room, reducing response time and realizing flat management.
(3) Introduction of new information technology and equipment
MES system is different from PCS. There are many departments and personnel involved in this system, and the process is relatively long. How to improve MES participants to obtain relevant and valuable information in real time has become a concern of iron and steel enterprises. MES not only focuses on production control but also cares about the management of raw materials, fuels, spare parts, work-in-progress, and finished product warehouses. The effect of such huge material management is not particularly satisfactory if it is only solved by manual and information technology.
Therefore, the MES system can introduce system instant messaging tools, handheld terminals, SMS, WAP, etc. to improve the timeliness of participants to obtain information. MES can also obtain information on the location and quantity of materials in the material warehouse area by collecting barcode data, RFID data, and data from handheld terminals, so as to avoid errors caused by human input and make it more accurate to manage materials.
(4) System Simulation
MES receives orders and related standard systems from ERP, formulates production plans and operation plans according to the production capacity of on-site equipment, and ensures smooth production through production control and adjustment of production when on-site equipment fails. However, the situation on site is more complicated, and the result of production scheduling often does not reach the optimal scheduling effect.
In the automotive industry, because its production line has high requirements for flexible production, the CATIA system simulates the logistics supply and production rhythm after arranging the production operation plan to ensure that the products can be produced on time with quality and quantity.
The iron and steel industry also needs system simulation. After the operation plan is formulated, the simulation is used to test whether the process is balanced, whether the energy supply is sufficient, and whether the production rhythm is appropriate.
(5) Introduction of crane positioning technology
Crane positioning technology has been applied in many domestic iron and steel enterprises, but most of them are used in finished product warehouses to manage the storage area of finished products. The applied technologies are mostly laser positioning, linear code ruler, absolute value encoder, RFID technology, Proximity switch, etc.
From the perspective of positioning technology comparison, laser positioning is greatly affected by the environment and is not suitable for the relatively harsh environment of the steelmaking workshop; the positioning accuracy of the linear code ruler is high, but the cost is high, and the crane is in the process of lifting finished products or iron ladles The strong gravity makes the crane shake and cause the phenomenon of collision with the ruler, and the maintenance cost of replacing the code ruler is too high; the cost of the absolute encoder is relatively low, but the signal is mostly DP line and PLC and other equipment need to be installed on the crane, which increases the overall cost virtually. The cost of the system and the slipping of the crane needs to install magnetic proximity switches for correction at key route points, making it difficult to implement the system.
RFID has been widely used in the positioning of cranes in recent years. It is low in cost and easy to maintain. It mainly installs RFID card readers and antennas on the cranes and installs RFID cards at the track stations of the cranes. According to different recognition distances, Depending on the positioning accuracy of the crane, an RFID card with a frequency of 13.56M or 900M is used.
Crane positioning technology can be applied in many processes in iron and steel enterprises. For example, in the steelmaking workshop, the introduction of the crane positioning technology can effectively track iron and steel ladles through the storage area divided by the steelmaking workshop. The change of the weight signal can judge whether the ladle is being hoisted, and can match the working conditions of each process of ladle steelmaking production with the collected weight, temperature, and work position, providing a “one-button” steelmaking basic information.
For example, in the steel rolling workshop, in the shearing line and heat treatment line, the storage area is divided into storage areas, and the position information and weight data fed back by the crane positioning can track the online and offline conditions of the steel plate. The steel-making workshop can realize online and offline without human intervention. full track. Compared with installing the crane terminal on the crane in the rolling workshop, this solution has relatively greater advantages in terms of cost, maintainability, and labor participation.
(6) Energy management
EMS is a management system that runs through the first, second, and third levels. Domestic large and medium-sized iron and steel enterprises have successively started the construction of energy management and control center systems.
Whether the energy management and control center system can be successfully applied in iron and steel enterprises firstly depends on the combing, optimization, and reorganization of business processes to truly realize flat management and realize collaborative operation in the process of energy dispatching in emergencies; secondly, it depends on the transformation of on-site instruments. Most of the energy management and control systems of enterprises are transformation projects, which require the transformation of on-site watt-hour meters and measuring instruments to realize data collection; followed by a set of management systems suitable for iron and steel enterprises, including spot inspection systems for unattended stations, emergency accident plan, etc.
(7) Equipment management
The reliability of the equipment and the shutdown maintenance plan directly affect the preparation of the MES operation plan, so they also occupy an equally important position in the MES. According to the experience of on-site construction services, equipment management is divided into three parts according to the equipment operation status: pre-event management, in-event management, and post-event management.
Pre-management is to formulate an equipment point inspection plan, maintenance plan, and grease supply plan, which are pre-plans formulated for preventive maintenance; in-event management is to analyze the reliability of equipment by collecting equipment-related data (such as temperature data, and vibration data), formulate the maintenance plan and grease supply plan in advance; post-event management mainly includes point inspection performance management, maintenance performance management, equipment failure performance management, etc., completes the establishment of equipment operation files through the collection of post-event performance for data analysis, and formulates through the PDCA cycle More consistent with equipment preventive maintenance programs.
At present, the domestic iron and steel industry does not pay enough attention to the equipment management system, but its benefits cannot be ignored. Improve the reliability of equipment through equipment management (the loss of unplanned shutdown of steel plants due to equipment failure cannot be counted), reduce the working capital occupied by spare parts (steel plant spare parts occupy hundreds of millions of funds), and reduce the time for fault maintenance, can create hundreds of millions of benefits for iron and steel enterprises.
(8) Knowledge management
The production of many processes in iron and steel enterprises has not yet achieved standardization in the true sense. Some processes rely on the furnace chief and operators for years of work experience for production; the maintenance of some equipment and the replacement of spare parts completely rely on some experienced staff; After the steel grades of some specifications have not been produced for many years, restarting production will require repeated tests and so on.
Therefore, iron and steel enterprises have gradually begun to pay attention to the sharing of explicit and tacit knowledge through informatization. As a three-level management system, MES has a large amount of valuable data. By organizing this valuable information to establish a knowledge base, using the knowledge base to guide production can make MES production control more in line with the on-site situation.
(9) Interface with ERP
As a three-level system connecting the previous and the next, whether MES can realize the data interface with the existing ERP interface is a technical issue that many iron and steel enterprises are very concerned about. At present, most large and medium-sized iron and steel enterprises have used ERP systems, and the brands are mostly SAP, ORACLE, Kingdee, etc., and some steel mills have adopted joint development or self-customized ERP systems. How to achieve tight coupling or loose coupling between MES and ERP systems The interface is also a key issue for the smooth operation of the system.
(10) Interface with other systems
Traditional MES usually interfaces with secondary systems of each process to grasp production process data in a timely manner to realize production control. However, during the construction service process, it was found that some domestic MES manufacturers interfaced the MES system with the inspection and testing system, measurement management system, quality management system, transportation management system, etc., thus enriching the reference ability of MES production control data and providing decision-makers Making more accurate decisions provides a basis, making iron and steel enterprises more dependent on the use of MES systems.
In the iron and steel industry, the level of equipment and automation of domestic large and medium-sized iron and steel enterprises is comparable to that of foreign iron and steel enterprises, and some domestic iron and steel enterprises have advanced equipment and automation levels in the world, but why first-class equipment cannot produce first-class steel products is a problem that troubles the managers of iron and steel enterprises. Experts point out that it is caused by the extensive management mode of my country’s iron and steel enterprises, so MES as a production management system has a broad market in China.
While introducing foreign advanced management models, MES digs deep into the problems that arise in the production process of domestic iron and steel enterprises, makes it combines advanced management models with enterprise management models, and uses advanced technology to effectively solve problems in enterprise production management, which can make MES reflects greater benefits in iron and steel enterprises.