Valve flow coefficient
According to the structure of the principle of classification, is the country
Valve flow coefficient is a measure of the capacity of the valve flow indicators, flow values indicate the greater the fluid flow through the valve when
The smaller the pressure loss. Foreign industrial valve manufacturer in developed countries most of the different pressure levels, different types and
Different DN values flow valve included in the catalog for the design department and the use of selected units. Flow coefficient
Value with the valve size, form, structure and changes in different types and different specifications of the valves must be tested separately before
Able to determine the valve flow coefficient.
1. The definition of flow coefficient
Coefficient of fluid flow through the valve, said pressure-generating unit of the flow of fluid loss. Due to the different units, flow
There are several different capacity factors and the value of the code.
2. Valve flow coefficient calculation
3. The typical flow coefficient data and the factors that affect the discharge coefficient
DN DN50mm various types of typical valve flow coefficient table.
With the valve flow coefficient of the size, form, structure and change. Several typical flow valve with the diameter of the variable coefficient
And shown in Figure 1-9.
For the same structure of the valve, fluid flow through the valve in various directions. Flow values also change. Such a change
General is due to pressure caused by the restoration of different. If the fluid flow through the valve so that tends to open the valve, the valve and valve body to form the ring has been the proliferation of channels will enable the restoration of the pressure. When the fluid flow through the valve so that tends to close the valve, the valve seat of a great influence on the pressure recovery. When the valve opening is & # + or more hours, the proliferation of downstream valve angle allows the flow in two directions, there will be some pressure to resume.
As shown in Figure 1-11 for the high-pressure angle, when the flow of fluid so that tends to close the valve when a higher flow coefficient, when the proliferation of cone valve seat so that the restoration of fluid pressure. Internal valve geometry is different from the curve of flow coefficient are also different.
The restoration of the valve mechanism of internal pressure, and venturi contraction and proliferation of the pressure loss caused by the same mechanism. When
Valve pressure drop within the same pressure if the valve can be restored, the flow coefficient will be larger, the flow also will be greater.
Pressure recovery and the valve cavity geometry, but the more important depends on the valve, valve seat structure.
, The most commonly used international classification method.