Experts, could anyone please explain to me the relationship between the CV value of a control valve, its nominal diameter, and the seat valve?
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Experts, could anyone please explain to me the relationship between the CV value of a control valve, its nominal diameter, and the seat valve? Since the selected CV value is 70 and the pipe diameter is DN50, what should be the nominal diameter of the pipeline and the diameter of the valve seat?
How to answer this kind of question. . Let’s first understand the definition.
The nominal diameter has little impact on the CV value; it only determines the maximum CV value for that valve. There is a one-to-one relationship between the seat diameter and the CV value.
There is a connection, but it’s not absolute. A 70CV value roughly corresponds to a valve seat size of SQRT(70/10) = 2.6 inches; therefore, valve body sizes of 2.5/3/4 INCH can be selected. 6-inch valves rarely come with 2.5 valve seats.
Do you have any academic materials on this topic that you could send me for reference?
Is it correct to understand that the effective diameter of a valve determines its CV value, and the CV value in turn determines the diameter of the valve seat? Do you have a reference value for the maximum CV of the valve?
Cv/ X: Earlier I assumed that X=10 (referring to a single-seat valve). X is related to the valve type/FL/size; see the data highlighted in red in the diagram. This method can only estimate the valve seat size (inches)