EFA Technologies

MassPack™ is included with each LEAKNET™ system.

MassPack™  is a mass balance system incorporating dynamic correction for changes in line pack.

MassPack™  monitors all flow into and out of a pipeline segment. Once each minute the mass flow balance and the change in the fluid packed within the line are computed and accumulated in four accumulators operating over different time periods. The first accumulator looks at the line-pack-corrected mass balance over a user-selected interval of 1 to 99 minutes. The second accumulator monitors the previous hour.  The third accumulator watches the previous 24 hours. The fourth accumulator can be user-set to watch either the entire proceeding month, or it can totalize the inflow volume until manually reset. This last option is useful for batch transfers and during loading or unloading of ships or tanks.

MassPack™ is tolerant of measurement inaccuracy. You may use custody transfer meters or the simplest of flow meters. Sensitivity, however, depends directly on the accuracy of the meters.

MassPack™  is a simple and reliable supplementary method for Stand-Alone use or as an effective partner with PPA™.

MassPack™ is a fully independent leak detection module designed to complement and work synergistically with Pressure Point Analysis™ (PPA™). MassPack™ is included in every LEAKNET™ system.

MassPack™provides sensitive mass balance leak detection and incorporates dynamic compensation for changes in line pack.

Principle of Operation

All flows into and out of a protected segment are monitored.  Once each minute the mass flow error is computed and accumulated.  When the accumulated error indicates fluid is being lost and when the amount lost exceeds a warning or alarm setting, the operator is alerted.  All warning and alarm limits are user configurable.

Pressure changes affect the quantity of fluid packed into the line. Pressure at each end of the protected segment is monitored and used to compute the corresponding changes in the line pack.  These changes are used to adjust the mass balance errors so warnings and alarms are issued only as a result of an actual loss of fluid

MassPack™ is fault tolerant.  If pressure readings for pack compensation are unavailable, it reverts to simple, uncompensated mass balance.


Each LEAKNET™ system includes the capability shown:



(PPA)™. Points

MassPack™ Segments

Meters per Segment

















Flow Metering Equipment

MassPack™ works with any reasonable metering system.  For maximum performance, flow should be measured to custody transfer accuracy and presented to MassPack™ as either mass flow rate or standard volumetric flow rate (e.g. 60 ° F barrels per hour).

Metered flows should be corrected for temperature by an external flow computer.  MassPack™ does not include temperature compensation.  The user may include a meter factor for each meter.

Pressure Measuring Equipment

Pressure should be measured to custody transfer accuarcy. (e.g. to the nearest 0.1 psi) using industrial quality pressure transmitters (e.g. Rosemount 3051).

Sensitivity and Detection Time

All mass balance leak detection relies on accumulating differences among inflow and outflow meters.  The higher the meter accuracy the faster and more sensitive MassPack™ can be.  MassPack™ is tolerant of low performance meters, but directly benefits from higher accuracy flow measurement.

Leak Detection Accumulators

MassPack™ includes four accumulators for each segment.  These accumulators compute the net flow imbalance over different intervals of time.



1 1 to 99 Minutes, user selectable
2 Previous Hour
3 Previous Day
4 Previous Month, or total to date until manually reset


MassPack™ is easily tuned to a specific  pipeline. This is done by online measurements and without extensive research or calculations.  Tuning values for 30 different operating configurations can be maintained online.

MassPack™ is a simple and reliable method for stand alone use or as an effective partner with PPA™