Foreword: In order to improve the maintainability of the electrostatic precipitator monitoring system and the visibility of the human-machine interface, an electrostatic precipitator host computer monitoring system based on the industrial control configuration software Kingview 6.55 was designed. The configuration software Kingview 6.55, the overall system structure, related software design and device driver preparation are introduced. This system has been applied in multiple electrostatic precipitator new construction or renovation projects, and the on-site equipment and systems are operating well. Practice has proven that the system has high stability, short development time, and a more vivid interface.
The electrostatic precipitator is the most effective dust removal equipment for treating flue gases from thermal power plants, steel plants, etc. and controlling air pollution. Because of its simple structure and easy maintenance, the electrostatic precipitator requires a one-time cost investment. Advantages such as small follow-up investment occupy most of the dust removal market of domestic coal-fired units. With the continuous deepening of industrial automation and the continuous development of network and Internet technology, the electrostatic precipitator monitoring system no longer exists in the form of an isolated system, but in the integrated production management and control system. Indivisible subsystem. therefore. It puts forward higher requirements on the reliability and maintainability of the electrostatic precipitator monitoring system and the visibility of the human-machine interface. Traditional host computer monitoring systems are mostly programmed in high-level languages such as Visual Basic or Visual C/C. Since this method is developed from the bottom level, it has greater flexibility. But it also has the disadvantages of long development cycle and not beautiful pictures. In industrial automation SCADA systems, configuration software is commonly used software for data acquisition and process control. Compared with other high-level languages. The configuration software has good openness, strong practicality, short development cycle, and intuitive and vivid interface. Therefore, our unit has developed a new type of electrostatic precipitator host computer monitoring system. The system is constructed based on Kingview, a domestic configuration software.
1. Introduction to Kingview
Kin~view is a product of Beijing Asia Control Technology based on the current development trend of automation technology. Facing the automation market and applications. A set of products developed with the goal of achieving enterprise integration. It is a general industrial monitoring software. Its purpose is to achieve optimal management of various production systems and applications as well as information exchange within the enterprise. The highlights of Kingview are mainly reflected in four aspects: ①Visual operation interface; ②Automatic establishment of I/O sites; ⑧Distributed storage of alarms and historical data; (Basic) Powerful equipment integration capabilities, which can connect most industrial equipment . Kingview also provides a rich configuration interface, including a large number of graphic elements and library elves. The abstract graphic images can vividly simulate and display the three-dimensional dynamic operating conditions of the site. Kingview supports common smart instruments, PLCs, data acquisition boards, smart modules, frequency converters, etc. on the market, and uses conventional communication interfaces for data communication.
2. Overall structural design
This article takes the electrostatic precipitator renovation project of a 6x350MW unit in a power plant in Shanxi as an example. The six furnaces in this project are units #1 to #6. Each furnace is equipped with two double-chamber five-electric field dust collectors. The high-voltage part of each furnace is equipped with a high-frequency power supply produced by a company in Hangzhou. The low-pressure part (including rapping, heating, and material level) is controlled by Siemens S7-300. The two furnaces share one upper computer and the lower computer uses Modbus TCP/IP for communication in the high-voltage part. Modbus communication protocol is an open fieldbus communication protocol. It has complete functions, is easy to use, and has an open protocol. It has been supported by many manufacturers and instrument manufacturers, and is becoming an industrial standard for instruments and intelligent terminals. The low-voltage part of the lower computer S7-300 is equipped with its own Ethernet communication module CP343-1. The communication protocol is S7-300 Ethernet, taking into account the long distance between the field equipment and the host computer. First, configure a communication box at the bottom of each dust collector. Connect the high-frequency power supply on the top of the dust collector to the communication box with a network cable. Because the distance between the top communication box and the electrostatic precipitator distribution room exceeds 100m. The maximum transmission distance of ordinary twisted pair is 100m, taking into account the problem of communication stability. Our company uses optical fiber to connect the communication box and S7-300 control cabinet. The distance between the S7-300 control cabinet and the host computer is relatively short. Using network cable connection, the system architecture is shown in Figure 1.
3. Kingview monitoring system design
The host computer monitoring system is designed using Kingview6.55 of Beijing Asia Control Company under Kingview’s WindowsMaker environment. When completing the entire project, changes will occur due to heat sources such as cutting and friction, and deformation will occur due to heat. For example, the workpiece will expand due to the influence of cutting heat during the machining process, which will lead to errors in the size and shape of the workpiece and greatly affect the accuracy. To this end, the incoming heat to the workpiece can be effectively controlled by selectively selecting tools and appropriately adjusting cutting parameters; in addition, cooling cutting fluid can also reduce the occurrence of thermal deformation to a certain extent: when clamped, it should Ensure the end of the workpiece. Especially large or long workpieces can be expanded and contracted arbitrarily.
Errors caused by internal stress in the workpiece and methods to reduce them
When cutting the workpiece, certain cutting forces and friction forces will inevitably occur. Under its influence, the inner structure of the workpiece will produce a hindrance, that is, a tensile stress will occur, which will cause the metal on the surface to produce a corresponding compressive stress and cause plastic deformation; the metal on the surface will undergo plastic deformation under the influence of cutting heat. Thermoplastic deformation occurs. But because its surface temperature dropped rapidly. The cooling shrinkage is much larger than that of the inner layer, so when the temperature drops to within the elastic deformation range. Due to the hindrance of the inner layer, a tensile stress will be generated on the surface layer.At this time, the inner layer will also produce a corresponding compressive stress to achieve a balanced effect. Reasonable design of the part structure, aging treatment and other methods can reduce the internal stress to a minimum.
Conclusie
This article briefly explains the composition and working principle of CNC lathes, studies the different ways to reflect machining errors during the machining process, and conducts a detailed analysis to first reduce the errors of the 2Y-art system to improve the machining accuracy of CNC lathes. In order to enhance competitiveness, machinery manufacturing companies have widely used advanced CNC technology. Drive industrialization through informatization, and promote informatization through industrialization. As a high-precision, high-efficiency automated machine tool, CNC lathes have played a good economic role in the mass production of complex parts.