API - MPMS 12.2.4
Manual of Petroleum Measurement Standards Chapter 12—Calculation of Petroleum Quantities Section 2—Calculation of Petroleum Quantities Using Dynamic Measurement Methods and Volumetric Correction Factors Part 4—Calculation of Base Prover Volumes by the Waterdraw Method
|Publication Date:||1 December 1997|
This document provides standardized calculation methods for the quantification of liquids and the determination of base prover volumes under defined conditions, regardless of the point of origin or destination or units of measure required by governmental organizations. The criteria contained in this document allows different individuals, using various computer languages on different computer hardware (or manual calculations), to arrive at identical results using the same standardized input data.
This publication rigorously specifies the equations for computing correction factors, rules for rounding, the sequence of the calculations, and the discrimination levels of all numbers to be used in these calculations. No deviations from these specifications are permitted since the intent of this document is to serve as a rigorous standard.
When most of the older standards were written, mechanical desk calculators were widely used for calculating measurement documentation, and tabulated values were used more widely than is the case today. Rules for rounding and the choice of how many figures to enter in each calculation step were often made on the spot. As a result, different operators obtained different results from the same data.
This five-part publication consolidates and standardizes calculations pertaining to the metering of petroleum liquids, using turbine or displacement meters, and clarifies terms and expressions by eliminating local variations of such terms. The purpose of standardizing the calculations is that all parties will produce the same unbiased answer from the given data. To obtain identical results from the same data, the rules for rounding, sequence, and discrimination of numbers (decimal places) have all been defined.