Calibration
Part No.: 44200004 - Revision 2
SVP Controller Operation Manual
4-19
4.5 Calculations
Volumetric Water Draw Calculations
Water draw volume corrections taken from API Manual of Petroleum
Measurement Standards API chapters,: 4.2, 4.9 and 12.2.4. and Appendix
B.4 F2.a, 11.2.3.5.
Symbols and Calculations from API 12.2.4:
Given:
RHOtm
= Density of liquid (water) in test measure. (API 12.2.4)
RHOp
= Density of liquid (water) in prover. (API 12.2.4)
CPL
=
Correction for the compressibility of liquid. (For water 3.2E-6)
T
b
= Base calibration temperature. (60 deg. F. in US)
G
a
= Area coefficient of expansion for flow tube. (API 12.2.1.11.2.1)
G
l
= Linear coefficient of expansion for detector. (API 12.2.1.11.2.1)
G
c
= Coefficient of expansion for the test measure
(from calibration certificate)
E
= Modulus of elasticity for flow tube material (from API 12.2 Appendix A)
WT
= Thickness of flow tube wall. (inches)
ID
= Diameter of flow tube. (inches)
Calculate:
BMVa = Base Measured Volume adjusted for scale reading.
= BMV + SR
CTDW = Correction for prover/test measure liquid temperature difference.
= RHOtm ÷ RHOp
CTStm = Correction for effect of temperature on test measure.
= 1 + (Ttm - 60) × (Gc)
CTSp = Correction for effect of temperature on prover.
= {(1+[(Tp-Tb)*Ga]) * (1+[(Td-Tb)*Gl])}
CCTs = Correction for prover/test measure steel temperature difference
= (CTStm)/(CTSp)
WD
= Adjusted Base Volume of Draw
= BMVa*CTDW*CCTs
CPSp = Correction for the effect of pressure on prover
= 1 + [(Pp*ID)/(E*WT)]