Developer Notes Client Query/Notes Field instruments Various field instruments are used in T&I applications: Level Measurement As per clause 7.11 (ii) of OISD 244, following instrumentation is to be provided for above ground tanks: a) Two numbers of independent level instruments should be provided. One shall be radar gauge type and other one shall be servo type or Radar type b) Over fill hard wired level switch like vibrating fork etc. shall be provided for actuating ROSOV Pressure Measurement In general, Pressure Transmitter are to be provided at station suction & station discharge headers, suction & discharge arms of mainline pumps, suction & discharge arms of booster pumps, before and after of the control valve, inlet & outlet exchange manifold at tank farm locations, inlet and outlet booster manifold, before/after station limit valves (towards previous/next station), tank delivery pressure, station inlet & outlet pressure near SRB/SLB, pressure monitoring of fire water network, air vessels and other locations as per P&ID Pressure Switch In general, Pressure Switch are to be provided at station inlet on the mainline, station outlet on the mainline, suction and discharge headers of MLPUs, suction & discharge arms of mainline pumps, suction arms of booster pumps, tank delivery line, and other locations as per P&ID Differential Pressure Measurement Differential Pressure Transmitter to be provided for continuous remote monitoring of differential pressure Temperature Measurement For measurement of process temperature measurement of the process fluid, temperature transmitter with RTD inserted in thermo-well to be installed. Thermo-well is to be inserted in the pipeline to be in direct contact with process fluid For measurement of temperature in piggable section of the pipe (i.e. at RCP/MOV locations, before/after station limit valve etc.), temperature transmitter with surface mounted weld pad welded to the main pipeline to be installed. In such case the RTD shall be inserted inside the weld pad welded on the main pipe Scrapper Detector Scrapper detector is to be installed at each inlet and outlet section of the pipeline before the station limit valve (towards station) Density Measurement Density measurement to be provided at all mother stations, product delivery stations, tank farm locations and terminal stations of petroleum product pipelines to monitor density Density measurement is the primary means of identifying the product flowing in the pipeline Viscosity cum Density Measurement Viscosity plays a critical part in establishing the flow condition in pipeline especially for crude oil pipeline where viscosity of the crude changes drastically along with density Viscosity cum Density measurement to be provided at all mother stations, refinery delivery stations, tank farm locations and terminal stations of crude oil pipelines to monitor density & viscosity Flow Switch Flow Switch to be provided at the sump pump discharge / transmix pump discharge to indicate low flow and in the surge relief line to indicate flow in surge line and other locations as per P&ID Flow switch in sump pump/ transmix pump discharge should be set for falling flow (which is to be based on the pump flow capacity) Flow switch in surge relief line should be set for rising flow to detect minimum possible flow in the surge line Click on each tab to know more