API PUBL 1149

Abstract

1.4 SCOPE <br> Three general types of software-based leak detection methods are addressed in this study: (1) mass balance, (2) mass balance with linefill correction, and (3) transient flow analysis. The leak detection potential of these methods will be discussed based on hydraulics to the extent possible. Specific implementations of software-based methods will be avoided. <br> The liquids considered are crude oils and refined petroleum products such as gasoline, jet fuel, and fuel oil. <br> The pipeline configuration considered is a pipe segment with pressure, temperature, and volumetric flow measurements at each end. During steady-state flow, this configuration applies to pipelines with booster pumping stations where rates of flow are measured only at the inlet and the outlet of the entire system. <br> All variables affecting leak detection will be listed. General relationships between the variable uncertainties and leak detection potential will be analyzed. The methodology will be described and verified with field tests. The variables will be ranked according to their importance to leak detectability. A step-by-step method and a data base will be established to enable simple hand calculations for establishing leak detectability based on mass balance. The method and the data base will be verified with field data. The rationale and the procedure to establish leak detectability using mass balance with line pack correction and transient flow simulations will be given and illustrated with examples and field trial results.