Common use of Flow Elements Clause in Contracts

Flow Elements. Flow Nozzles and Venturis Venturi nozzles shall also be used for all flows used for primary control. Orifice plates may be used for other flow measurements. Flow transmitters will be the differential pressure type with the range matching (as closely as practical) the primary element. Linear scales and charts will be used for flow indication and recording. Critical steam and natural gas flow meters (if appli­cable) will be temperature and/or pressure compensated, and air flow measure­ments will be temperature compensated. Differential pressure type instruments shall normally be used for flow measurements where suitable for the application. Flow transmitters shall be the essentially zero volume displacement differential pressure type. Bodies shall normally be carbon steel with stainless steel internal trim, unless other materials are required for the particular services. Overrange protection equal to the body rating shall be provided. Wherever possible, the maximum differential range in inches of water shall not exceed the static absolute pressure in psia in a compressible fluid application. Span shall be continuously adjustable over at least a 5:1 ratio. Variable area flow meters may be used for small flow rates where local indication is required. They may also be used where rangeability, nonlinearity, viscosity, or the hazardous nature of the fluid makes the differential pressure-type instrument unsatisfactory. They shall normally be the armored type with magnetic pick-up, except for water and air below 200 psig and 1-inch-or-smaller lines where glass tubes may be used. All glass tube area meters shall have front and rear plastic guard plates. Positive displacement meters shall be used to measure those flows where a highly accurate integrated flowing quantity is desired.

Flow Elements. Flow Nozzles and Venturis The flow elements for feedwater flow to the HRSG will be laboratory-calibrated venturi flow nozzles. Venturi nozzles shall also be used for all flows used for primary controlcontrol of the HRSGs or steam turbine. Orifice plates may be used for other flow measurements. Flow transmitters will shall be the differential pressure type with the range matching (as closely as practical) the primary element. Linear scales and charts will shall be used for flow indication and recording. Critical In general, feedwater flow meters shall be temperature-compensated when the water temperature is greater than approximately 250oF; critical steam and natural gas flow meters (if appli­cableapplicable) will shall be temperature and/or pressure compensated, ; and air flow measure­ments will airflow measurements shall be temperature compensated. Differential pressure Differential-pressure-type instruments shall normally be used for flow measurements where suitable for the application. Flow transmitters shall be the essentially zero volume displacement differential pressure type. Bodies shall normally be carbon steel with stainless steel internal trim, unless other materials are required for the particular services. Overrange protection equal to the body rating shall be provided. Wherever possible, the maximum differential range in inches of water shall not exceed the static absolute pressure in psia in a compressible fluid application. Span shall be continuously adjustable over at least a 5:1 ratio. Variable area flow meters may be used for small flow rates where local indication is required. They may also be used where rangeability, nonlinearity, viscosity, or the hazardous nature of the fluid makes the differential differential-pressure-type instrument unsatisfactory. They shall normally be the armored type with magnetic pick-up, except for water and air below 200 psig and 1-inch-or-smaller lines where glass tubes may be used. All glass tube area meters shall have front and rear plastic guard plates. Positive displacement meters shall be used to measure those flows where a highly accurate integrated flowing quantity is desired.