American Petroleum Institute

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 2-Measurement Tickets - THIRD EDITION
 N MPMS 12.2.2

Annotation

This document provides standardized calculation methods for the quanti?cation of liquids and the determination of base prover volumes under de?ned conditions, regardless of the point of origin or destination or the units of measure required by governmental customs or statute. The criteria contained in this document allow different entities using various computer languages on different computer hardware (or manual calculations) to arrive at identical results using the same standardized input data.

The publication rigorously speci?es the equations for computing correction factors, rules for rounding, calculational sequence, and discrimination levels to be employed in the calculations. No deviations from these speci?cations are permitted since the intent of this document is to serve as a rigorous standard.

Purpose

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 ?gures 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 metering petroleum liquids using turbine or displacement meters and clari?es terms and expressions by eliminating local variations of such terms. The purpose of standardizing calculations is to produce the same unbiased answer from the given data. So that different operators can obtain identical results from the same data, the rules for sequence, rounding, and discrimination of ?gures (or decimal places) have been de?ned.