The power station valve is the main part in the safe operation of the power station, and its importance is self-evident. When it is used, external leakage is often prone to occur. If it is not handled properly, once leakage occurs, it will not only affect industrial production to a certain extent, but also endanger the safety of people's lives and properties; sometimes, it even affects the harmony and stability of society. The power station valve is connected to the main and auxiliary equipment and systems of the power station, and its importance is beyond question.
The external leakages of power station valves mainly include the following types:
The external leakages of power station valves mainly include the following types:
(1) Leakages of valve packing
The valve stem and packing will form a state of movement between each other, which will be reflected in the use of the valve. The more times the valve is opened and closed, the more movement there will be. In addition, the effects of temperatures and pressure will greatly increase the possibility of leakages of valve packing. During this time, the pressure of the packing will gradually decrease, resulting in aging and elasticity. The pressure medium will leak from the contact gap between the packing and the valve stem. If this problem is not properly solved, as time goes by, the packing will be blown away and the valve stem will be separated from the groove, making the leakage area bigger and bigger.
(2) Leakages of flanges
There are often more than one reasons for leakages of flanges, such as insufficient compression force of the gasket, roughness of the joint surface not meeting the requirements and deformation of gaskets. As a result, the gasket and the flange are not fully contacted; a gap appears, and leakage occurs. Meanwhile, the reasons for the poor sealing of the flange surface are the deformation or elongation of the bolt, the aging of the gasket, the decrease in the resilience, and the cracking, which can also cause leakages. Human factors are also the cause of leakages of flanges that require special attention. In addition, the leakage also occurs for the valve body due to the limitation of space.
(2) Leakages of flanges
There are often more than one reasons for leakages of flanges, such as insufficient compression force of the gasket, roughness of the joint surface not meeting the requirements and deformation of gaskets. As a result, the gasket and the flange are not fully contacted; a gap appears, and leakage occurs. Meanwhile, the reasons for the poor sealing of the flange surface are the deformation or elongation of the bolt, the aging of the gasket, the decrease in the resilience, and the cracking, which can also cause leakages. Human factors are also the cause of leakages of flanges that require special attention. In addition, the leakage also occurs for the valve body due to the limitation of space.
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