ASME MFC-11M:2003 pdf download

ASME MFC-11M:2003 pdf download.MEASUREMENTOF FLUID FLOWBY MEANS OFCORIOLIS MASS FLOWMETERS
1 SCOPE
This Standard, ASME MFC-11M, gives guidelines for the selection, installation, calibration, and operation of Coriolis meters for the determination of mass flow, den- sity, volume flow, and other related parameters of flow- ing fluids. It also gives appropriate considerations re- garding the fluids to be measured. The content of this Standard is primarily applied to the metering of liquids. This Standard also gives guidance, within specified lim- its, to the metering of other fluids, mixtures of solids or gas inliquids, andmixtures ofliquids. AlthoughCoriolis meters may be used for gas measurement, specific guid- ance for gas measurement is not within the scope of this Standard.
2 TERMS AND DEFINITIONS
The terminology and symbols (Table 1) used in this Standard are in accordance with ASME MFC-1M. Terminology not defined in ASME MFC-1M but used in ASME MFC-11M are also defined in this paragraph. Some items from ASME MFC-1M are also listed in this paragraph for easier reference. accuracy ofmeasurement: the degree of freedom from er- ror; the degree of conformity of the indicated value to the true value of the measured quantity (see ASME MFC-1M). calibration: for the purpose of this Standard, calibration strictly refers to the procedure by which the flowmeter is checked against a traceable reference and does not include adjustment to the calibration factors. calibration factor(s): numerical factor(s), also called flow calibration factors, unique to each primary device and determined by flow calibration, which when pro- grammed into the transmitter, enables the meter to per- form to its stated specification (see the note in para. A1 of Appendix A for a definition of calibration). density calibration factor(s): calibration factor(s) asso- ciated with density measurement.Coriolis meter: a device consisting of a flow sensor (pri- mary device) and a transmitter (secondary device), which measures the mass flow by means of the Coriolis force generated by flowing fluid through oscillating tube(s); it may also provide measurements of density and temperature. cross-talk: if two or more Coriolis meters are to be mounted close together, interference through mechani- cal coupling may occur. This is often referred to as cross- talk. The manufacturer should be consulted for methods of avoiding cross-talk. elemental error: the bias and/or precision error associated with a single source or process in a chain of sources or processes (see ASME MFC-1M). flashing: the formation ofvapor bubbles in a liquid when the line pressure falls to or below the vapor pressure of the liquid, often due to local lowering of pressure be- cause of an increase in the liquid velocity (see ASME MFC-1M). flow rate: the quantity of fluid flowing though a cross section of a pipe per unit of time (see ASME MFC-1M). mass flow rate (q m ): the rate of flow of fluid mass through a cross section of a pipe (see ASME MFC-1M). volume flow rate (q v ): the rate of flow of fluid volume through a cross section of a pipe (see ASME MFC-1M). flow sensor (primary device): a mechanical assembly con- sisting of an oscillating tube(s), drive system, measure- ment sensor(s), supporting structure, flanges/fittings, and housing. drive system: means for inducing the oscillation of the tube(s). housing: environmental protection of the flow sensor. measurement sensor: sensor to detect the Coriolis ef- fect and to measure the frequency of the tube oscilla- tions. oscillating tube(s): tube(s) through which the fluid to be measured flows.transmitter (secondary device): electronic system provid- ing the drive and transforming the signals from the flow sensor to give output(s) of measured and inferred parameters; it also provides corrections derived from parameters such as temperature. uncertainty of measurement: the range within which the true value of the measured quantity can be expected to lie with a suitable highprobability (see ASME MFC-1M). zero offset: flow measurement indicated under zero flow conditions. zero stability: maximumexpected magnitude ofthe meter output at zero flow after the zero adjustment procedure has been completed, expressed by the manufacturer as an absolute value in mass per unit time.