Before you start working on to prepare spec for DP type flow transmitter few things you should keep in mind
Differential Pressure work on the principal of measuring the differential in pressure created due to the restriction in the flow of process or flowing liquid.
I) For Measuring flow this DP Type Transmitter can be used for the measuring DP across following Type of Instrument
Orifice Plate
Anuubar/Pitot Tube
Venturie Tube
Flow Tube /Nozzles etc
Basically it works on for all those device which creates restriction in flow path and thus leads to creation of differential head which could be measured to calculate flow.
It Uses the principal of flow is proportional Sq rt of DP
Generally Transmitter available in market catter to good range but special precaution needs to be given for operation in
Low temperature
Space constraint for Transmitter
( for space constraints
II) Pressure Transmitter for measuring pressure from single Tapping
Generally pressure transmitter used for this pupose is has one one inlet and is either closed at other end or sensing element is generally such that it is
For service with hydrogen it is advised to have Gold Plated SST for Diaphragm/Wetted material
Silicon is used as filled fluid for.