ASME MFC-10M:2000 pdf free download

ASME MFC-10M:2000 pdf free download.METHOD FOR ESTABLISHING INSTALLATION EFFECTS ON FLOWMETERS.
Under certain circumslances, flowmcter coefficient shifts and calibration errors causcd by installation effects (pipe flow phenomena). i.e.. flow pattern, pulsations. etc.. can be significant. These changes can be most severe when a ilowmeter is moved froni an installation in which there are long lengths of straight pipe upstream and downstream of the meter. to an installation where the meter is mounted close to a disturbing pipeline element such as an elbow, valve, or pump. Because different types of flowmeters can be affected differently by the amc flow pattern, it becomes important to know the (low pattern sensitivity of a given flowmeter in order to properly use it. 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 perlirmance 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 perfonnance. 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 effects, the changes in the metering performance of a llowmeer are obtained by evaluating the signature (e.g., flow coefficient versus Reynolds number), bias, and precision of a meter when it is (low calibrated in reference and nonreference piping.
Step 2. Install thc flowmctcr rn the Lcst loop with any convenient upstream straight pipe length. but with at least four pipe diameter lengths of straight pipe downstream of the meter. If the manufacturer of the flowmeter specifIes minimum upstream and downstream lengths. then these are the minimum lengths to be used in this and subsequent steps.
Step 3. Make a full calibration of the flowmeter in this location. A full calibration is one that includcs calibrations at several flow rates, prcfcrably eight or more, spaced over the flow rate range of the meter.
Step 4. Repeal the full calibration in at least one additional orientation 45 deg or more from the first, provided this change is within the scope of the manufacturer’s specifications. Note that instead of rotating the tlowmeter. it is permissible to rotate only the disturbing elements for this test. Additional calibrations. each at new angular orientations that are up to ‘X) deg from previously used orientations. may be desirable. A sufficient number of these calibrations should be pcrtbrmcd to ensure that the uncertainty of the flowmeter can be reliably staled.
Step 5. Install the Ilowmeter with at least five additional pipe diameters of longer upstream piping and with the same downstream pipe.
Step 6. Repeat the full calibration in the same orientations as in Step 4.
Step 7. Repeat Steps 5 and 6 until an upstream length can be established beyond which the flowmeter’s signature. bias, and precision arc independent of location and orientation. This condition can be considered satisfied if the calibration data obtained at this and other downstream locutions agree within a 95* confidence interval as defined in NIST
1297. The location nearest to the disturbance at which the above condition is satisfied can he considered the shortest reference piping for the flowmeter.
Step 8. The shortest reference downstream piping for a flowmeter and for a given downstream piping disturbance can he established in a similar manner but, in this case, the upstream reference piping should remain unchanged.