© 2019 Department of Petroleum Resources. All rights reserved Department of Petroleum Resources (DPR) PROCEDURE GUIDE

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b) After the ball has passed the second micro-switch, it moves into rest within the
housing tee. The ball has now completed a proving trip. This trip is equivalent to a
proving run if the uni-directional Prover loop is used. With the bi-directional type, the
ball is again launched, and the movement of fluid is reversed in order to obtain a
complete run.
c) The duration of each run is obtained in seconds by using a stop watch. The
electronic counter registration and the duration for the complete run are recorded.
d) Proving inlet and outlet pressure and temperature readings are recorded as each
proving run is in progress. Upon completion of each complete run and when all the
data obtained have been recorded, the electronic counter is reset to zero and
additional proving runs are made.
e) Sufficient runs shall be made to verify the repeatability of the system. However, a
set of five consecutive runs, which checks within 0.020% (2 counts per 10,000
counts), should be obtained before a proving exercise is regarded as successful and
acceptable. The gravity of the fluid flow during proving must also be determined.
f) When proving manifolds are not equipped with automatic samplers, it is desirable
that samples be collected from a sampling point located on the prover loop until
such a time that automatic samplers are installed on such metering manifolds.
Sampling should be done when a set of five acceptable runs have been made.
Ambient temperature reading for each sample shall also recorded.
2.6.4 Meter Proving Report
A Standard Meter Proving Report Sheet is divided into “Meter Volume Data” and “Prover
Volume Data”. All the data obtained during meter proving shall be properly entered in the
Meter Proving Report Sheet and this shall form the basis for Meter Factor calculation.
2.6.4.1 Meter Factor Calculation
The known volume of Prover was calibrated at 60oF at atmospheric pressure. The Prover
and metered volumes shall be corrected to the same standard using the under listed
correction factors. When calculating meter factors or measurement tickets for the effect of
temperature and pressure, use valid tables of values. When two or more correction factors
enter a calculation, multiply them together in a set sequence.

a) Temperature Correction Factor for Steel (CTS)
This shall be computed from the following formula:
CTS ={1 + (𝑇−60°𝐹) ∗𝐺𝐶}
Where T = observed temperature in oF
GC = mean coefficient of cubical expansion per oF for the material of which the
container is made between T and 60°F.

b) Temperature Correction Factor for Liquid (CTL)
This is the volume correction factor obtained from API MPMS Chapters 11.1 and 12.