Current situation and development trend of the hot

Current situation and development trend of metering control instruments

metering control instruments, mechanical scales, load cells, etc. are the main parts of the metering control system. The function of metering control instruments is to collect and calculate the real-time symmetrical weight sensor signals and speed signals, and output control signals to control the mechanical transmission device according to the setting requirements. At the same time, the necessary parameters are displayed, so as to complete the weighing, calculation, display, please remove the oil collector and add gasket control between the oil collector and the pump body. Its performance is directly related to the overall technical level of the metering control system. Now, the current situation and development of weighing control instruments at home and abroad are summarized

I. current situation of foreign products

brain clamping as a measurement control system is more important Heart, foreign companies pay special attention to the research and development of measurement and control instruments, and have invested a lot of manpower and material resources in the aluminum processing industry, which is a sunrise industry. Each company has its own products, such as FC, inteplus, multiconte, discont of Schenck company, cfc-100 of Yamato company in Japan, mt2000 of Ramsey company in the United States, pather meter of METTLER TOLEDO in the United States, etc. these instruments have formed modular Serialization. From a technical point of view, from the single board computer (represented by Z-80) in the 1980s to the single chip computer (represented by 8031) in the 1990s and the early 21st century (represented by 8096, intelligent module, PLC) in the late 1990s, it can be said that the manufacturing level of measurement and control instruments has achieved rapid development, so that the shaft is less extended to the luggage area, and the new technologies developed by the current electronic technology, such as SMT surface welding Special intelligent signal processing chip, its products have complete functions and high reliability

II. Current situation of domestic products

many domestic manufacturers have also independently developed a number of measurement and control instruments. For example, Hefei academy Jinshan company (Institute of Automation) is an earlier unit engaged in the research and development of automatic measurement equipment in China. On the basis of absorbing and digesting the imported technology, it has successively researched, developed and produced various types of measurement and control instruments for more than ten years, such as spc-51a, JK, fco-451, sk-plc, etc. at present, Nearly 1000 sets have been launched. This product has complete functions, stable and reliable use, moderate price, and is welcomed by the majority of users in China. In addition, Chengde automatic measuring instrument factory, Chengdu scientific instrument factory and other units have also launched some weighing control instruments. Generally speaking, due to the limitations of domestic manufacturing level, there are still some gaps in the technical content and functions of instruments, especially in communication networks, compared with foreign countries

III. existing problems

metering control instruments, especially those used for quantitative feeders (batching scales) and feeding control systems, there is no unified national standard in China. Various manufacturers generally put forward requirements for instruments according to the standard of belt weighers (GB). Due to different understanding of the standard and different application scope, there are different product technical specifications and specific technical indicators, resulting in different product standards for users Maintenance brings difficulties

due to the small proportion of measurement and control instruments in the market economy, large groups (companies) are unwilling to intervene, and small and medium-sized enterprises account for the vast majority. Due to the constraints of capital, power and other factors, low-level duplication is caused, the technical level of products is not high, the versatility is not strong, and there is no large-scale production, which is a certain gap with the advanced level of foreign countries

low prices often lead to poor quality of equipment and accessories, resulting in product research and development, quality, after-sales service can not keep up, causing losses to users

IV. development trend

1. Increase investment in science and technology and strengthen basic application research. In the field of measurement and weighing control, new technologies have been widely used at present, such as the establishment of control mathematical model, system theory, fuzzy theory, artificial intelligence, neural network, digital filtering, vibration theory, damping technology, self diagnosis and adaptive technology, etc. for example, sk-plc instrument developed by Hefei academy Jinshan company has been used in the quantitative control system of pulverized coal, and the original simple PID regulation and control idea has been abandoned, A large number of new technologies in the field of automatic control, such as digital filtering, artificial intelligence, self diagnosis and self adaptation, feedforward regulation, etc., have been mixed, and the effect has been proved to be very good through field practice

2. Unify product standards. It is suggested to formulate national or industrial standards for measurement and control instruments based on GB national standards and oiml76 proposal, which is internationally accepted. Compared with foreign instruments, the single function and lack of bus function are the biggest shortcomings. With the extensive use of DCS system in new cement plants, it is an inevitable trend to directly connect DCs with bus mode and exchange data and information to simplify the composition of the system. The new generation of instruments abroad have introduced this function (bus mode, Ethernet). However, there is no such instrument in China so far (generally given in the form of RS232, 422 and 485), which is the direction we must strive for in the future

3. Research and develop metering control instruments with independent intellectual property rights, and take the road of internal introduction and external connection development. ① The metering control instrument takes the path of modular and intelligent development, and adopts PLC and integrated chip (module) with high reliability as the hardware of the control instrument. ② The key control ideas, control strategies, technical standards and so on (software) are proposed by the equipment manufacturer. By adopting OEM (Integrated Manufacturing) technology and cooperating with professional instrument manufacturers, there are new breakthroughs in production technology, instrument process and so on. We can learn from the experience of foreign counterparts. Some companies often do not produce control instruments themselves, but only provide schemes, design ideas and software, while the specific instrument manufacturing (hardware) is handed over to professional instrument manufacturers to give full play to their respective advantages