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Keywords: petrochemical; valve device; on-line detection technology 1 Introduction In mechanical products, valves are a commonly used device. The safety of valves has a profound impact on the quality and safety of mechanical products. Therefore, the safety of valve use has been widely used in various sectors of society. s concern. From the point of view of use, the valve acts as a control element of the fluid piping system, and by effectively isolating the equipment and the piping system, the control of the system backflow and the adjustment of the pressure can be realized. Valve is an indispensable component in petrochemical refining equipment, which is of great significance for improving the refinery performance of petrochemical industry. However, from the actual situation, the valve will have different degrees of leakage during the process of use, which seriously harms the valve. Petrochemical refining operations are safe and have an adverse effect on the surrounding environment after valve leakage. This article explores the application of valve detection technology in petrochemical plants.
2 Types and causes of valve leakage in petrochemical plants 2.1 Types of valve leakage in petrochemical plants Valve leakage in petrochemical plants is mainly divided into two types, namely valve leakage and valve leakage. The leakage of the valve mainly means that the medium leaks from the inside to the outside under the action of a certain joint surface. Or the medium leaks from the inside to the outside between the stem and the packing. The internal leakage of the valve mainly refers to the leakage of the medium inside due to the tight sealing operation of the valve disc, the valve core and the like.
2.2 Causes of valve leakage in petrochemical plants 2.2.1 Causes of leakage of valves in petrochemical plants Combined with the connotation of leakage of valves in petrochemical plants, relevant personnel may infer the leakage of valves according to the specific position of the leakage of valves in the inspection work. specific reason. First, the cause of leakage of the valve occurring at the valve body. The main reason for the leakage of the valve occurring in the valve body is that the quality of the valve body itself does not meet the relevant standards. From the actual application situation, the valve body is a kind of component formed by human processing and casting, and some quality defects are easily caused by various factors in the process of casting and processing. For example, because the valve body itself is uneven in texture and the presence of a gap may cause leakage due to damage of the valve body. For the reason of valve body leakage, relevant personnel need to strengthen the inspection of product quality during the process of valve body casting. Second, the valve leaks because of the poor quality of the valve body. In order to fully exert the role of the valve in petrochemical production and processing, it is necessary to ensure the flexibility of the valve stem. In the specific operation, if the quality of the valve stem is not closed, the valve leakage problem is easy to occur. To this end, relevant personnel are required to strengthen the strict inspection of the quality of the valve stem to ensure the scientific and effective construction of the sealing packing. Third, the valve leakage problem caused by poor sealing of the valve stem connection. During the sealing operation of the valve body and the bonnet, some quality safety hazards are likely to occur, causing valve leakage problems. For this reason, relevant personnel are required to strengthen the inspection of the sealing property of the valve stem connection part during construction.
2.2.2 Causes of internal leakage of petrochemical plant valves First, valve leakage problems caused by unqualified valve sealing surfaces are produced. In practical applications, the surface roughness of the valve sealing surface and the application of the sealing material profoundly affect the quality of the valve. If the requirements of the relevant standards are not met, different degrees of valve leakage may occur. Second, the internal leakage of the valve caused by improper operation. In actual operation, if the operator uses too much force or operates too fast when applying the valve at the construction site, it will damage some parts of the valve, and even damage the sealing surface of the valve, accelerate the consumption of parts and cause endoleak problems. Third, the valve leakage problem caused by the tight connection between the valve ring and the valve seat. Due to the deformation of the valve stem and the influence of some component errors, the valve sealing surface can not be tightly fitted together, thereby failing to exert the sealing protection effect of the valve sealing surface, resulting in the leakage problem of the valve.
3 Application of online detection technology for petrochemical plant valves 3.1 Common detection methods for valve leakage of petrochemical plants The common detection methods for valve leakage of petrochemical plants are divided into two types, direct detection method and indirect detection method. When the direct detection method is applied, the detector is installed outside the valve to directly detect whether the valve has leaked oil and gas resources. Common direct detection methods are light detection method and gas leak detection method. The indirect detection method mainly detects whether the detector leaks through the operating parameters of the valve. Common indirect detection methods include model method and running pressure method.
3.2 On-line detection technology for petrochemical plant valves 3.2.1 Negative pressure wave method When the oil and gas valve leaks, the pressure at the valve leakage position will decrease instantaneously. The reason for the instantaneous decrease in pressure is that the material inside the pipe leaks, and the density of the local liquid decreases after the leak. If the pressure of the valve is lowered, the fluid medium will propagate from the inside to the outside, accelerating the occurrence of leakage. In response to this problem, the application of negative pressure wave measurement method can accurately locate the leaking valve, and timely discover the subtle changes of the fluid medium and reduce the loss.
3.2.2 Acoustic emission method In the process of detecting the oil and gas pipeline valve, if the sealing performance of the valve is poor, the oil and gas pipeline valve is prone to leakage during the process of use. The fluid medium produced by this leakage will have an impact on the sealing surface, which is accompanied by an acoustic signal. In order to detect the valve leakage problem in time, relevant personnel are required to install the corresponding elastic wave by installing an acoustic emission sensor on the outer wall of the valve, and then convert these elastic waves into an electrical signal to improve the accuracy of the valve leakage detection result.
In the actual detection operation, the advantage of the acoustic emission method is that the detection operation is convenient, and the detection result is convenient for observation. At the same time, the application of this detection method can achieve effective disassembly of the valve, thereby improving the performance of the valve. The acoustic emission method has low requirements on the detection environment in the specific detection operation, and it is difficult to judge some objects that are flammable, explosive, toxic and harmful.
3.2.3 Mass balance method The mass balance method can detect the medium quality of the valve and the quality of the outflow valve medium during use, and judge whether the valve leaks through scientific and reasonable calculation. However, from the actual application situation, this method is only suitable for valves that you dare to use in the medium flow. For valves with large media flow, it is impossible to effectively detect, so the problem of internal leakage of the valve cannot be found in time.
3.2.4 Direct observation method The direct observation method mainly refers to the problem that the relevant personnel judge whether there is leakage in the process of using the oil and gas valve by observing and hearing according to years of work experience. The main operating principle of the direct observation method is human. In actual operation, it is impossible to ensure that the valve is observed all the time, and it is difficult to find and solve the valve leakage problem in the first time.
3.3 Future application prospects of on-line detection methods for petrochemical plant valves From the actual development situation, the leakage of petrochemical plant valves will bring unpredictable losses to the development of oil companies and also harm the construction of a harmonious society. The development of social economy and science and technology puts higher requirements on the detection of valves in petrochemical plants. Traditional human-based periodic inspections cannot ensure the effectiveness of testing and safety of testing. To this end, relevant personnel need to use the latest technology form to find new detection methods, and take effective measures to solve the problem of oil pipeline leakage at the first time, thereby effectively improving the effectiveness of valve leakage detection and avoiding waste of resources to the maximum extent. The emergence of the environment to reduce pollution.
4 Conclusion In summary, under the in-depth development of the scientific concept of development, people have put forward higher requirements for the detection of petrochemical plant valves. In order to achieve the goal of environmental protection development, relevant personnel need to strengthen the valve leakage problem of petrochemical plants. Concerned, combined with the type and cause of valve leakage in petrochemical plants, adopt the corresponding on-line monitoring technology of petrochemical plant valves, such as negative pressure wave detection technology, mass balance detection technology, direct observation detection technology, acoustic emission detection technology, etc. The application of various technologies ensures the safe use of valves in petrochemical plants and promotes the long-term development of petrochemical enterprises.
references:
[1] Chen Qun. Application Research of Valve On-line Detection Technology in Petrochemical Plants[J]. Tax, 2017(33): 194.
[2] Chen Xiaoli. Analysis of valve sealing and leakage problems in petrochemical plants [J]. Biochemical, 2016(6).
[3] Su You. Research on valve sealing and leakage of petrochemical plant[J].Industrial,2016(8):79.
[4] Li Dean. Common causes of damage and treatment measures for safety valves in petrochemical plants [J]. Enterprise Technology Development, 2016(15): 110.
[5] Su Xiang, Li Qiang, Guo Jin. Research on valve sealing and leakage of petrochemical plants [J]. China New Technology and New Products, 2016(4): 186.
Research on on-line detection technology of petrochemical plant valves
Abstract: Under the rapid development of social economy, people's demand for oil and gas has increased accordingly. However, oil and gas resources are a kind of non-renewable resources. Therefore, in the process of use, it is necessary to realize the rational use of oil and gas resources, strengthen the detection of valves of oil and gas chemical plants, and avoid the occurrence of oil and gas resources waste. This paper combines the types and causes of oil and gas valve leakage in petrochemical plants, and explores the application of on-line detection technology for petrochemical plant valves.