Orifice Plate-Water
Orifice Plate-Water
(OP)
Hi all.
I need a white paper showing some calculations for sizing an orifice plate with flange taps. Round bore, through hole (no taper). My application is as follows: 10" ID pipe, 200 inH20 pressure drop. 80 psia line pressure. 300 gpm flow rate. Flange taps (1" up and down stream).
Thanks,
-Chris
I need a white paper showing some calculations for sizing an orifice plate with flange taps. Round bore, through hole (no taper). My application is as follows: 10" ID pipe, 200 inH20 pressure drop. 80 psia line pressure. 300 gpm flow rate. Flange taps (1" up and down stream).
Thanks,
-Chris





RE: Orifice Plate-Water
M777182
RE: Orifice Plate-Water
Pressure 65.000 psig(79.696 psia )
Temperature 80.0 Deg F
Ambient Pressure 14.696 psia
Liquid Gravity (Gf) 0.998
Viscosity 0.878 cP
normal | maximum
Flow 300.0 | 400.0 Gpm (flowing)
Pipe Reynolds No. (Rd) 107740 | 143653
Mean Fluid Vel. (Pipe) 1.2 | 1.6 ft/Sec
Line Loss 0.02 | 0.04 (psi)/100 ft
Friction Factor (f) 0.0187| 0.0187
Meter Loss(Installed) 3.59 | 6.38 psi
Meter Bore (d) 2.8810 @ 20 Deg C
Pipe i.d. (D) 10.0000 Inches
Beta Ratio (d/D) 0.2881 Inches/Inch
Metal Expansion (Fa) 1.0002 (316 Stainless)
Expansion Factor (Y1) 1.0000
Reynolds Factor (Fc) 0.9960
Drain/Vent Corr. (Fh) 1.0000
Discharge Coef. (Cd) 0.59850
Spinks Factor (S) 0.05005
normal | maximum
Meter Differential (h) 112.5 | 200.0 in w.c.
Flow Rate 300.0 | 400.0 Gpm (flowing)
Q (Gpm) = 5.667*S*D^2*Fa*Fc*Fh*sqrt( h / Gf )
RE: Orifice Plate-Water
RE: Orifice Plate-Water
5167-2 has specific correlation equations for the discharge coefficient (Cd) of orifice-plate meters.
You'll probably want to get both. Mine are also on white paper, because that's what my printer has loaded in it...
BTW, 5167-3 shows correlations for nozzles and truncated nozzles.
RE: Orifice Plate-Water
good luck,
RE: Orifice Plate-Water
Review the API Manual of Petroleum Measurement Stnadards Chapter 14, Natural Gas Flow Measurement, Section 3 for Concentric Square Edged Orifice Meters.
Also look at ASME MFC-3M-1989 section 4.2 Method of Sizing the Bore of the Selected Primary Element.
Perhaps you can find an old book called something like Flow Meter Engineering by Spink that provides an easy method for calculatin an orifice plate. The technology has advanced lots since the book was published. However, if you need something easy to use for a PE exam, consider using Spink. It is close enough for multiple choice.
John
RE: Orifice Plate-Water
RE: Orifice Plate-Water
Have I over-simplified or over-complicated this? My numbers are very close to that calculated above, within a 1%.
RE: Orifice Plate-Water
RE: Orifice Plate-Water
your reynolds no. correction is at the 0.4% level