API MPMS 12.2 -2021 pdf free download

API MPMS 12.2 -2021 pdf free download.Manual of Petroleum Measurement Standards Chapter 12.2.
3.1.16 Net standard volume NSV The gross standard volume (GSV) corrected to exclude non-merchantable components such as sediment and water (S&W). 3.1.17 nominal k factor NKF The number of pulses generated or electronically manufactured by the meter per indicated unit volume. 3.1.18 pass A single movement of the displacer in a displacement prover that activates the start-stop detectors. 3.1.19 proving report A document showing all the meter and prover data together with all the other parameters used to calculate the reported meter factor. 3.1.20 proving report number A number that is uniquely assigned to a proving report. 3.1.21 quantity calculation period The period of time over which the calculated total quantity is to be integrated. 3.1.22 round trip The combination of a single pass of the displacer in one direction (e.g. forward) followed by a single pass of the displacer in the opposite direction (e.g. back) in a bi-directional displacement prover. 3.1.23 run One pass of the displacer between detectors on a unidirectional prover; one round trip of the displacer between detectors on a bi-directional prover; one flling or emptying of an atmospheric tank prover between the upper neck scale level reading and the lower neck scale level reading or zero reference on an open tank prover; or a single start and stop proving test run with a master meter in series with a line meter. 3.1.24 sampling period The time between the retrieval of live input variables. 3.1.25 weighted average An average in which each incremental component of the average is weighted according to its impact upon the whole. 3.2? Symbols? and? Abbreviations For the purposes of this document the following symbols and abbreviations apply.
6.2 Register Precision and Rounding 6.2.1 Precision The physical property standard will specify the minimum precision of the device used to calculate densities and volume correction factors. The minimum foating-point precision for calculating fow-weighted averages shall be 32bit IEEE foating point precision. Electronic accumulator volume registers (stored result of fnal total volume quantity) used in continuous calculations shall be a minimum 64bit IEEE foating point precision or a scaled 32bit integer equivalent. Mechanical registers are only used in the Discrete Method and shall be used at the discrimination of the mechanical register up to the discrimination of Table 8. Measurement tickets using calculations from an ofsite calculation program, such as SCADA or DCS, may be used. When transmitting data to an ofsite location, the potential arises to obtain a diferent result than the fow computer. To prevent this diference, the minimum precision outlined in this document shall be followed, regardless of the location of the calculation. The user should also ensure that the selected communication protocol does not alter the data from the onsite to ofsite device. 6.2.2 Rounding Specifc rules apply for when and where to round. When rounding is performed on input feld data and output calculations, it shall be done in strict accordance with the discrimination levels in Section 7 of this document. When a number is to be rounded to a specifc number of decimals, it shall always be rounded of in one step to the number of fgures that are to be recorded and shall not be rounded in two or more steps of successive rounding. The rounding procedure shall be in accordance with the following: a) When the fgure to the right of the last place to be retained is 5 or greater, the fgure in the last place to be retained should be increased by 1 . b) If the fgure to the right of the last place to be retained is less than 5, the fgure in the last place retained should be unchanged.
6.3? Averaging 6.3.1 General Correction factors are derived using process input data such as density, temperature, and pressure. Process variables used to calculate correction factors for measurement tickets for custody transfers shall be averaged on a quantity weighted basis. Process variables and intermediate factors used to calculate a meter factor shall be averaged on an arithmetic mean basis. 6.3.2? Flow-weighted? Averaging? (FWA) For ticketing, all input and output calculation variables that are used to calculate gross standard volume (GSV) shall be Flow-weighted averages (FWA) which can be applied to calculation variables such as temperatures (TWA), pressures (PWA), and densities (RHObWA, RHOobsWA). It is essential that the calculation variables be sampled and weighted in a fow proportional manner so that high fow rates are not undersampled and low fow rates are not oversampled.