ASME MFC-22:2007 pdf download

ASME MFC-22:2007 pdf download.Measurement of Liquid by Turbine Flowmeters
1 SCOPE
This Standard describes the criteria for the application of a turbine flowmeter with a rotating blade for the measurement of liquid flows through closed conduit running full. The standard discusses the following: (a) considerations regarding the liquids to be measured (b) turbine flowmeter system (c) installation requirements (d) design specifications (e) the maintenance, operation, and performance (f) measurement uncertainties This Standard does not address the details of the installation of accessory equipment used to measure pressure, temperature, and/or density for the accurate determinationofmass orbase volumes,or thoseaccesso- ries used to automatically compute mass or base volumes.
3 DEFINITIONS AND SYMBOLS
Much of the vocabulary and many of the symbols used in this Standard are defined in ASME MFC-1M. Others that are unique in the field under consideration, or with special technical meanings are given in para. 3.1. Where a term has been adequately defined in the main text, reference is made to the appropriate paragraph. 3.1 Definitions base flow rate: flow rate converted from flowing condi- tions to base conditions of pressure and temperature, generally expressed in units of base volume per unit time (e.g., gpm, m 3 /h, etc.). base pressure: a specified reference pressure to which a fluid volume at flowing conditions is reduced for the purpose ofbillingand transfer accounting. Itis generally taken as 14.73 psia (101.560 kPa) by the gas industry in the U.S. base temperature: a specified reference temperature to which a fluid volume at flowing conditions is reduced for the purpose of billing and transfer accounting. It is generally taken as 60°F (15.56°C) by the gas industry in the U.S. base volume: volume of the fluid at base pressure and temperature. flowing pressure: static pressure ofthe fluid at the flowing condition. flowing temperature: the temperature of the fluid at the flowing condition. linearity: linearity refers to the constancy of K factor over a specified range, defined by either the pipe Reynolds number or the flow rate. A typical liquid turbine meter performance curve is shown in Fig. 1. The linear range of the turbine meter is usually specified by a band defined by maximum and minimum K factors, within which the K factor for the meter is assumed to be K mean . The upper and lower limits ofthis range can be specified by the manufacturer as a function of maximum and minimum Reynolds number ranges, a flow rate range of a specified fluid, or other meter design limitations such as pressure, temperature, or installation effects.rangeability or turndown: flowmeter rangeability is the ratio of the maximum to minimum flow rates or Reynolds number in the range over which the meter meets a specified uncertainty and/or accuracy. repeatability ofmeasurements (qualitative): the closeness of agreement among a series of results obtained with the same method on identical test material, under the same conditions (i.e., same operator, same apparatus, same laboratory, and short intervals of time). reproducibility: the closeness of agreement between results obtained when the conditions of measurement differ; for example, with respect to different test appara- tus, operators, facilities, time intervals, etc. Reynolds number: a dimensionless parameter expressing the ratio between inertia and viscous forces. turbine meter: a flow measuring device with a rotor that responds to the velocity of flowing fluid in closed con- duit. The flowing fluid causes the rotor to move with a tangential velocity that is directly linearly proportional to the volumetric flow rate.