How to measure the flow on PIBCV valve?

[Diego_Ramirez]

Hello all,

Could someone indicate me please how do I measure the flow on the PIBCV valves using the PT ports?

[Ted_Roman]

@Diego_Ramirez 

Should be able to use ports if required to verify flow the same as balancing valve. 

https://www.contractingbusiness.com/service/article/20870767/service-clinic-how-to-measure-flow-thro... 

Flow setpoint is set with dial on actuator.

Best regards,

Ted

[Simon_Firth · Accepted solution]

Hi, Measuring the flow is a relatively complex topic using the P-T ports and actually varies depending on which type (size/design) of valve we are using.

Document: F-28105 describes in detail the exact process for verifying the pressure and flow through all the DN10-250 valves.

F-27984 is the equivalent document for the 1/2" to 10" valves in the US with units of measurement in PSI and GPM

Basically, on the smaller valves, DN10 to DN32 (3/8" to 1-1/4") then the two P-T ports available are only used to verify the working pressure supplied to the valve is at the needed minimum level for the differential pressure regulator to work effectively.  If you do have the needed working pressure available, then you can be assured that the flow for any percentage setting scale on the valve is accurate and according to a document F-28130. This  F-28130 document declares the flow for any stroke limit (ie. flow setting considering the valve stroke limit is dependant on the set point setting).

For the larger valves with three test ports  where we are able to measure the full pressure drop across both the pressure regulator and the control valve portion of the valve as well as at the point in-between these components, then these pressures tapping's / readings are used alongside a table of effective Kvs to calculate the flow.. The comprehensive document guides: F-28105 Metric units / F-27984 - US units have these tables of effective Kvs/Cvs but there is also a simpler doc F-28088 available for just the DN40-250 valves.

[Anonymous user]

Mathematically it is easy to see how, as the authority of a control valve is defined as: N = DPv / (DPv + DPc). Where: DPv = Pressure drop across a fully open control valve DPc = Pressure drop across the remainder of the circuit.

[Alfred69]

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@mcdvoice survey wrote: 

Hello all,

Could someone indicate me please how do I measure the flow on the PIBCV valves using the PT ports?

---

The smaller valves, DN10 to DN32 (3/8" to 1-1/4") then the two P-T ports available are only used to verify the working pressure supplied to the valve is at the needed minimum level for the differential pressure regulator to work effectively. If you do have the needed working pressure available, then you can be assured that the flow for any percentage setting scale on the valve is accurate and according to a document F-28130.

[greg_peterson_s · Accepted solution]

Please refer to SmartX PIBCV Pressure and Flow Verification F-27984 which you can be used with your commission/balancing agency. Here is the link.

https://ecoxpert.se.com/search?documentUUID=010b9c88-9c29-426b-a372-877c6fa54af2&title=PIBCV%20Smart...

Best Regards,

Greg Peterson