Due to different on-site processes, there are many influencing factors. Nowadays, the principle of the instrument is as many as 10 kinds and the type is not less than 200. In the industrial automation system, the quantity accounts for only one-fifth of the system automation instrument, but the price accounts for about one-third; in the scientific evaluation of energy saving, pollution emission, accounting for more than half of the monitoring instrument. Therefore, it has an important position in the national economy.
First, market assessment
1. Foreign markets
According to Flowresearch's online survey, the average annual growth rate (CAGR) of the world market for flow meters has reached 2.6% over the past five years. The sales growth has increased from 3.1 billion U.S. dollars in 2002 to 2007. US$3.5 billion, of which traditional instruments (throttle, volume, turbines, rotor flowmeters, etc.) are negative growth, CAGR is -2.2%, from 1.643 billion US dollars in 2002 (53% of the total) to 1.505 billion in 2007 The US dollar (43%), while the new meter (electromagnetic, ultrasonic, Coriolis flowmeter, etc.) average annual growth rate of 6.2%, from 1.457 billion US dollars in 2002 increased to 2.019 billion US dollars in 2007. The electromagnetic flowmeter's CAGR is less than 2% due to its large base and mature technology.
The survey believes that turbine flowmeters are commonly used in many countries in the world to measure gases or liquids with low viscosity. Due to the rotating parts in the meters, the maintenance workload is large. The CAGR for the past 5 years is -3.2%, and the sales amount is from 2002. The 410 million U.S. dollars fell to 348 million U.S. dollars in 2007. Experts believe that although ultrasound has been growing aggressively in recent years, turbines are much cheaper than ultrasound and have price advantages. Compared with throttling devices, the range ratio can be as high as 10:1, and it is more accurate. In trade settlement, it is still small and medium-sized. Customers are happy to choose. Volumetric flowmeters are non-velocity instruments. Installation requires no straight pipe sections. Accuracy can generally reach ±0.5%, but it is cumbersome. The caliber is generally less than 0.2m. In the past five years, sales fell from 520 million U.S. dollars in 2002 to 452 million U.S. dollars in 2007, and the CAGR was -2.7%. Experts believe that new instruments replace conventional instruments in many fields and are an overall development trend, but the process will be long. Please visit: Power Transmission and Distribution Equipment Network for more information
2. Domestic market
According to statistics, in the domestic automated instrument market in 2005, the annual sales flow meter expressed 2.3 billion yuan; the pressure transmitter is about 1.8 billion yuan (of which about 500 million yuan differential pressure transmitter and differential pressure flow meter ); temperature instrument 1.2 billion; level, level instrument 1 billion. From the point of view of the type of flow meter, because the throttling device is relatively heavy and the technical content is relatively low, foreign manufacturers have not basically involved in the Chinese market for this type of product. The selection of such instruments in China's projects is mainly based on domestic products, and the annual sales volume. Not less than 200,000 units, about 600 million yuan or more.
China's efforts to develop and develop flow meters have a large gap with foreign countries and are more satisfied with imitation. This issue can be seen from the well-known instrumentation show MICONEX2006. At this exhibition, Chinese and foreign manufacturers exhibited a total of 297 flow meters with more than 10 principles. Of the 16 items classified, a total of 204 exhibitors of the first 6 items accounted for 69% of the total, indicating that they are currently at home and abroad. Instrument manufacturers are concerned about the hot spots, and Coriolis flow meters, foreign exhibitors have 17 accounts for 68% of the total, only 8 domestic, whether to explain this accurate measurement of the mass flow of the instrument, whether domestic attention is insufficient; and the inner cone flow The total number of domestic exhibitors reached 30, accounting for 91% of the total; there are only three foreign countries. Is the domestic market overheated?
• Electromagnetic flowmeters are still hot spots in flow meters and they are in the first place. China's major instrument manufacturers have listed it as a major product, including Dalian Yuke. According to the assessment of the US ARC Consulting Company, due to the special emphasis on environmental protection in recent years, China has depended on the rapid development of Sheung Shui/Sewer, metallurgy, mining, pulp and pharmaceutical industries. In the next five years, the electromagnetic flowmeter in China's CAGR will reach 10.7%. In 2003, the increase from 380 million yuan to 640 million yuan in 2008.
• Ultrasound has many advantages, including accuracy, low pressure loss, and is particularly suitable for the trade measurement of precious fluids. It is highly valued at home and abroad. However, domestic exhibits are mostly fluids, and there are several gas sensors that are used in the field. Especially for trade settlement there are still some problems.
• Thermoelectric exhibits are also many, because it can measure the mass flow, and the sensitivity is high, the industry's attention, but its plug-in form can only measure dry, pure gas, accuracy is not advertised by the manufacturers High, it's still a long way from practicality.
Second, the development trend
1. The structure is becoming simpler and lighter
Early flow meters are purely mechanical on-site displays, such as positive displacement flow meters. Not only is the structure complex and bulky, the weight/aperture ratio is large; and the rotating parts therein require frequent maintenance due to wear. With the increasing diameter of industrial pipelines, plug-in meters are increasingly favored by users due to their simple structure, light weight, and easy assembly and disassembly. In the past decade, the fastest-developing electromagnetic and ultrasonic flow meters have no rotating parts. , Resistance parts, the structure is more concise, and the pressure loss is small, high accuracy, is the most potential flow meter.
2. Function to improve and diversity
Early flow meters were used for on-site display (such as volume and rotor). With the continuous improvement of the industrial level, it has been unable to meet the technical requirements of dozens of meters to display, adjust and control. It is necessary to separate the sensor (also known as a table, orifice, nozzle, cone) from the transmitter (also known as the secondary meter). The flow parameters are converted into electrical parameters and transmitted to the central control room. With the expansion of industrial scale, analog signals can no longer be adapted, and output signals need to be converted into digital signals to meet the requirements of field bus systems and SCADA systems.
In order to increase the reliability of the instrument, many instruments have added more than 10 kinds of self-diagnosis functions. Such as excellent instrument electromagnetic flowmeter, self-diagnosis such as air bubbles, electrode corrosion, fouling, electrode short circuit, fluid conductivity, non-full pipe, lining damage, external magnetic field and other aspects of the instrument status.
The diversification of instrument functions is also a trend of development. For example, in addition to measuring flow, ultrasound can also measure fluid composition and sound velocity. In addition to measuring flow, Coriolis can measure fluid density.
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