Emerson 8600 Gas Heater User Manual


 
95
Reference Manual
00809-0100-4860, Rev BC
Appendix A: Reference Data
January 2013
Specifications and Reference Data
Permanent pressure loss
The approximate permanent pressure loss (PPL) from the Rosemount 8600D flowmeter is
calculated for each application in the Vortex sizing software available from your local
Rosemount representative. The PPL is determined using the equation:
where:
Minimum upstream pressure (Liquids)
Flow metering conditions that would allow cavitation, the release of vapor from a liquid, should
be avoided. This flow condition can be avoided by remaining within the proper flow range of the
meter and by following appropriate system design.
For some liquid applications, incorporation of a back pressure valve should be considered. To
prevent cavitation, the minimum upstream pressure should be:
PPL = Permanent Pressure loss (psi or kPa)
Where:
f
=
Density at operating conditions (lb/ft
3
or
kg/m
3
)
Q =
Actual volumetric flow rate (Gas = ft
3
/min or
m
3
/hr; Liquid = gal/min or l/min)
D = Flowmeter bore diameter (in. or mm)
A = Constant depending on meter style, fluid type
and flow units. Determined per following table:
Table A-4. Determining the PPL
Meter
Style
English Units SI Units
A
Liquid
A
Gas
A
Liquid
A
Gas
8600DF 3.4 ϫ 10
-5
1.9 ϫ 10
-3
0.425 118
P = 2.9P + 1.3p
v
or P = 2.9P + p
v
+ 0.5 psia
(3.45 kPa) (use the smaller of the two results)
P = Line pressure five pipe diameters downstream of
the meter (psia or kPa abs)
P = Pressure loss across the meter (psi or kPa)
p
v
= Liquid vapor pressure at operating conditions
(psia or kPa abs)
PPL
A
f
Q
2
D
4
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