Solartron Mobrey 7828, Техническое руководство

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Calculated parameters 7828 Density Transmitter Technical Manual
B-4
78285000_AA
For refined products the values of K
0
and K
1
are automatically selected according to the
corrected density:
Hydrocarbon
Group
Density Range
(kg/m³)
K
0
K
1
Gasolines 654 to 779 346.42278 0.43884
Jet Fuels 779 to 839 594.54180 0.0000
Fuel Oils 839 to 1075 186.9696 0.48618
For Crude Oil the API factors are:
Product K
0
K
1
Crude oil 613.972226 0.0000
User defined factors can be entered as any sensible value.
Density / Pressure Relationship
Isothermal secant compressibility can be defined by the simplified equation:-
β
δ
=






1
0
1
1
V
V
P
t
where liquid volume changes from V
0
to V
1
as the gauge pressure changes from zero
(atmospheric) to P
1
where
β
= Isothermal secant compressibility at temperature t
δ
V
1
= Change of volume from V
0
to V
1
P
1
= Gauge pressure reading (P - 1.013) bars
hence
ρ
ρ
β
0
1
1
1
= −
P
where
ρ
0
= Corrected density at zero (atmospheric) gauge.
ρ
1
= Uncorrected density
P
1
= (P - 1.013) where P is pressure in bars (P - base)