ASME MFC-10M pdf download.METHOD FOR ESTABLISHING INSTALLATION EFFECTS ON FLOWMETERS.
Under certain circumstances, flowmeter coefficient shifts and calibration errors caused by installation cffrcts (pipe flow phenomcna. i.e.. flow pattern, pulsations. etc.. can be significant. These changes can be most severe when a flowrneter is moved from an installation in which there are long lengths of straight pipe upstream and downstream of the meter. to an installation where the meter is mourned close to a disturbing pipeline element such as an elbow, valve, or pump. Because different types of flowmeters can be affected differently by the same flow pattern, it becomes important to know the flow pattern sensitivity of a given flowmeter in order to properly usc ii This pattern sensitivity is established by first determining the performance of a meter in a reference installation and then determining the variations in the meter’s performance caused by other installation conditions.
When preparing programs to test for installation effects, it should be realized that the purpose of the tests is to uncover effects that change the metering performance. These effects may be stated as a function of the flow profile at the meter, the pertinent parameters such as Reynolds number, relative roughness. etc.. and the type of disturbing element, the flow condition entering it. and the distance separating it from the meter.
When analyzing installation efkcts. the changes in the metering performance of a llowmeter are obtained by evaluating the signature (e.g., flow coefficient versus Reynolds number). bias. and precision of a meter when it is flow calibrated in reference and nonreference piping.
1 SCOPE
This Standard establishes methods for determining the influence of installation conditions or flow patterns on the performance of llowmeters in closed conduits (i.e.. pipe. ducts. etc.).
This Standard also addresses
NOTE: When the asailaNc space at a test lio facility ur held site is inasletiuate fur the estalshshnwni of a sLaislard reference condition. then the facility or site alone cannot be uscd to determine inta1lation c’fkcts (see Section 6.3). Huwecr. a meter can he calibrated in-situ br a given installation in that facility. hut its calitwation curse is valid only for that facility or br a geiine1ricaiIy scaled installation in which penIrnnt Iluid dynamic paramelcr’. are the sane.
6 METHOD FOR ESTABLISHING
INSTALLATION EFFECTS ON FLOWMETERS
6.1 Nonreference Conditions
Nonreference conditions are those thai do not satisfy the definitions for the Basic or Working Reference Conditions given in Section 5. These nonreference conditions may be generated by upstream and/or downstream piping geometry such as single or multiple elbows, by upstream equipment such as a parlially opened gale valve, pumps. etc., or by the entrance or exit of a pipe. The flow disturbance must he defined and recorded. This includes the piping upstream of the disturbance, any flow conditioner that is used, upstream fittings, and the onenlation of system components.
6.2 Method of Establishing the Effects of Nonreference Conditions for a Single Flowmeter in a Given Facility
‘The effect of these nonreference flow conditions on the pcrfonnancc of flowmctcrs can be evaluated by first establishing the flowmcter performance under reference conditions, and then testing the meter in nonreference conditions and comparing the results, This will identify deviations that occur between reference and nonreference conditions, The calibration tests should be conducted over approximately the same nondirnensionalized parameter range (such as Reynolds number range) using the same fluid, instrumentation, and flowmeter as used in the reference condition calibrations. Enough data should be taken to statistically establish the uncertainty and the precision of the llowmetcr. See Section 8 regarding interpolation and extrapolation of results to untested fluids or conditions.
6.3 Method of Establishing the Effects of Nonreference Conditions for a Single Flowmeter Using Different Facilities.
ASME MFC-10M pdf download
