ASME MFC-6 pdf download

ASME MFC-6 pdf download.Measurement of Fluid Flow in Pipes Using Vortex Flowmeters.
(a) describes the use of vortex flowmeters, including their physical components, principle of operation, installation, performance, influence factors, and calibration in a closed conduit running full for the measurement of volumetric flow rate and volume flow total of single-phase liquids or gases, including vapors such as steam
(h) describes the use of vortex flowmeters in combination with one or more other process measurenwnts for the inferential measurement of mass flow rate, mass flow total, base volumetric flow rate, base volume total, and heat flow metering
Cc) is limited to lull-bore Ilowmeters and does not include the special case of insertion-type flowmeters
2 REFERENCES AND RELATED DOCUMENTS
Unless otherwise indicated, the latest issue of a referenced standard shall apply.
ASME MFC-IM, Gbssary of Terms Used in the Measurement of Fluid flow in Pipes
Publisher: The American Society of Mechanical Engineers
(ASME), Two Park Avenue, New York, NY 10016-
5990; Order Department 22 t.aw Drive, P.O. Box 2900,
Fairfield, NJ 07007.29(a) (www.asnw.org)
EEC 60529, Degrees of Protection Provided by Enclosures (lPCode)
Publisher: International Electrotechnical Commission (IEC), 3, rue de Varembé, Case Postalc 131, CH-1211 Genève 20, Switzerland /Suisse (www.iec.ch)
3 TERMINOLOGY AND SYMBOLS
3.1 Definitions From ASME MFC-IM Used In This Standard
For the purposes of this Standard, the following definitions are particularly useful in describing the characteristics of vortex shedding flowmeters. ASME MFC-1M provides a more extensive collection of definitions and symbols pertaining to the measurement of fluid flow in closed conduits.
(c) Gaskets shall not protrude inside the pipe.
(d) The flowmeter should be mounted with straight runs of pipe upstream and downstream. The straight runs should be free of changes in pipe size or schedule, and of pipe fittings, valves, and other internal obstructions. The minimum lengths of straight pipe required to obtain the specified accuracy at operating conditions differ depending on flowmeter construction and the nature of the piping configuration.
(e) II more than one pipe section is used within the minimum length of straight pipe, the joined pipe should be straight, with minimal misalignment. Welding rings should be avoided within the required number of straight pipe lengths.
(f) The required length of straight pipe may be reduced through the use of an appropriate flow conditioner or acceptance of higher uncertainties. The meter manufacturer should be consulted regarding the use of flow conditioners or their effect on meter uncertainty. This includes the type of flow conditioner, its sizing, and its location relative to the tlowmeter.
(g) The location of additional process measurements external to the meter, such as pressure, temperature, or densitv may impact the performance of a vortex flow- meter, and hence, these measurement points should be located downstream from the flowmeter.
(h) To satisfy the minimum measurable flow requirement, a meter size smaller than the pipe size may have to 1w used. Pipe reducers may be used upstream and downstream to install such flowmeters, When pipe reducers are installed without sufficient straight length of pipe, adjustment of the K factor or the uncertainty, or both, shall be made.
(i) In some applications it may be desirable to periodically inspect or clean the flownwter. If a bypass is installed to facilitate this, the fittings shall be ahead of the upstream straight length of pipe or flow conditioner and beyond the downstream straight section. The valve(s) used to shut of f main flow should be positive closing.
(j) When a particular meter installation is expected to deviate from the manufacturer’s recommendations, the user may desire to perform in situ calibration.
7.2 Flowmeter Orientation
Proper orientation of the flowmeter in the pipe may depend on the nature of the fluid. Flowmeters should be installed with the orientation recommended by the manufacturer. The orientation of the meter should take into consideration the temperature of the stream being measured and its effect on the transmitter.