Is this piping design reasonable (diameter calculation)?
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There is a hydrogen pipeline that contains other impurities, with a designed molecular weight of 5.9 (moles). The main pipeline has a diameter of DN200; the pressure before the control valve used in this pipeline is 0.456 MPAG, while the pressure after the valve is 0.455 MPAG. The bypass line serves as an emergency vent line, with a diameter of DN80; the pressure before the control valve used in this bypass line is 0.456 MPAG, whereas the pressure after the valve is 0.001 MPAG. Can the bypass line meet the design requirements when the flow rate is 14,000 NM? How to calculate it? Thank you for the advice!
First, it was felt that the pressure difference of the control valve was too low, at only 1 KPA. I asked the automation team whether such a low pressure difference could be achieved You need to check whether a pipe diameter of 200 is suitable; there’s only a marking, but no pressure – how can you proceed with the work?
Pressure should be the pressure before the control valve, right?
The flow rate of hydrogen must be less than 8 m/s; based on this flow rate, when the flow volume is 14,000 NM, the diameter of the pipe becomes much smaller.
I’ve started learning it too; I just got in and am learning*
I’ve started learning it too; I just got in and am learning*
A control valve with a pressure difference of only 1 KPA between the inlet and outlet is used solely for flow control; the pressure difference doesn’t matter. When the flow rate for the second device is set to 7000 NM, can the flow velocity be reduced?
Refer to the flow rate range of the medium; the flow rate of hydrogen should be less than 8 m/s, so that you can calculate the appropriate pipe diameter. Additionally, the selection of the bypass diameter for control valves can be referred to in the Installation of Control Valve Assemblies (Chemical Piping Manual).
When the design pressure of hydrogen is between 0.1 and 3 MPa, the maximum flow velocity in stainless steel is 25 m/s; therefore, the pipe diameter is appropriate
Learning*, there are so many experts around. :lol