Problems Existing in Power Station Valves

1. Introduction
As we all know, valves play an important role in various systems and are of great significance in the operation and production of the system. If there is a problem in the performance or quality of valves, it will bring a lot of economic losses to the enterprise. Therefore, it is necessary to strengthen the maintenance of the valve. In the operation of the power system, the importance of the valve is self-evident. Once a problem occurs, it will bring losses to the power industry. Among them, as the important device in the power station equipment and system, a power station valve is very important in the operation of the system. Therefore, it is necessary to effectively analyze and study the problems and defects existing in the power station valves, and find corresponding solutions to solve them to provide support for the normal use of the power station valves, thereby ensuring the high efficiency of the power station valves.
 
2. The overview of power station valves
A valve is a commonly used device to control the flow direction, open and close pipelines, and adjust and control the parameters of the conveying medium. Valves have functions such as regulation, diversion, and pressure regulation, and are widely used in various industries. A valve is an important fluid control device in the power station system, and has a direct impact on the normal operation of various pipeline systems. In order to ensure the safety and reliability of the valve in the operation of the unit, it is necessary to strengthen the supervision of each stage of the valve such as purchasing stages, manufacturing stages, packaging stages and transportation stages, ensuring the quality of the valve, and then providing a guarantee for the effective operation of various pipelines.
 
3. Problems existing in power station valves
As far as the quality of power station valves is concerned, the parameters for evaluating whether they are qualified include strength, stiffness, reliability, sealing, and service life. In the whole power system, the power station valve is an indispensable and important device, so when choosing the power station valve, valves with stable performance and high quality should be selected. Although a better valve is selected, there will still be some problems or failures in the actual application process, and the following aspects should be paid attention to:
 
3.1 Damage to the wedge
As an important part of the gate valve, the good performance of the wedge directly affects the operation of the gate valve. Therefore, it is necessary to pay attention to the wedge, ensure the sealing, and make them have good performance to play a real role. In the actual application process of the wedge, the tensile force, the compression force, and the scouring caused by the fluid are all important sources of its force. Regarding the sealing surface, the pressure mainly comes from friction and extrusion force, while the pressure of the wedge static pressure and residual stress. The static pressure is mainly caused by manufacturing factors such as liquid and valve seats. It can be seen from the above force analysis that complexity and diversity are important characteristics of the wedge. When the external load is great, it is likely to cause damage to the wedge. In addition, under the action of various forces, the liquid will be further strengthened, which will bring a certain corrosion effect to the sealing part of the wedge, which will reduce the sealing of the wedge, thereby causing damage to the wedge.
 
3.2 Failures of systems
The relevant investigation shows that the accident caused by the failure of the valve control system accounts for a large proportion of valve accidents. After a lot of research and analysis, it is known that the unreasonable opening of the valve and the lack of flexibility of the rotating structure are the main causes of the system and are the direct factor in failures in the valve control system. Among them, the opening of the valve directly affects orderly production, so we should pay attention to it. At this stage, there is more related research on the opening. It has gradually become the main direction and problem for the research. In terms of transmission mechanisms, under the background of continuous progress and development of science and technology, valves are gradually becoming digital and intelligent. Intelligent valves can be automatically adjusted according to different working conditions. To a certain extent, the flexibility of the valve is increased. In addition, the core part of the intelligent valve is the digital positioner. Through the application of the microprocessor, the positioning accuracy of the valve actuator can be improved, and the related data of the valve actuator can be effectively monitored and recorded.
 
3.3 Strength and service life
In addition to the above two problems, there are also problems with the strength of valves. The number of the unit's starting time determines the strength and service life of the valve, and the speed regulation of the regulating valve is an important factor. Therefore, it is necessary to ensure the strength and tightness of the valve so as to obtain high efficiency of the valve. Under normal circumstances, when the unit starts frequently, it is often difficult for the valve to meet the operating requirements. The main reason for this situation is that the strength of the valve is not enough, so it is necessary to strengthen the valve to ensure normal and effective operation of the valve. A valve should be designed according to the basic load in the process of valve design. Meanwhile, various factors such as temperatures, creep and static pressure should be fully considered. In addition, fatigue life should also be considered. If this problem is not taken into account, the valve design quality will be low and it will be difficult to meet the actual operational needs. Paying attention to fatigue life can make the design conditions consistent with the operating conditions, thereby prolonging the service life of the valve.