For Clean, Low Viscosity Liquids, Gases, and Steam
Valves Included as Standard
The FPT-6000 series has been discontinued. Please see the FPT-3000 series as a possible alternative or contact our Flow Engineering department.
The FPT-6000 is a highly accurate averaging pitot tube which generates a pressure differential between its
upstream (stagnation) ports and its downstream (static) ports that is proportional to the flowrate squared (Q2 ).
The differential pressure can then be measured by a differential pressure transducer (PX760 Series)
to provide a 4-20 mA output which is proportional to the flowrate squared. This can then be read out as flowrate
by devices with square root extraction, such as OMEGA’s DPF64-SQRT meter or FC-20 mass flow computer. The FPT-6000
can be used to measure clean, low viscosity liquids, gases and steam in a variety of piping systems and pipe sizes
(to 72" and above on special order).
The FPT-6000 offers the following advantages over orifice plates: easy, low-cost installation (weld 1 small coupling
into place vs. 2 large flanges); much lower permanent pressure loss; low maintenance (occasionally forcing gas through the
pressure ports clears the sensing ports when dirt is a problem); and good resistance to wear. Bi-directional flow
measurement capability is standard. And, with special double-mount construction, the flow ranges listed can be extended
by to up to 4 times
SPECIFICATIONS Accuracy: Up to 1% of rate (see sizing). (Accuracy stated is for use in schedule 40 pipe. If used in schedule 80 pipe, add 1% to accuracy or request special construction) Repeatability: ±0.1% of rate Max Temperature: FPT-6100: 93°C(200°F) FPT-6200: 204°C (400°F) Max Pressure: FPT-6100: 150 psig
FPT-6200: 1500 psig Unrecoverable Pressure Drop (inches H2O): = DP x (CP/D)
where: DP = generated differential pressure (inches H2O)
CP = pressure loss coefficient
= 0.296 for 3⁄8" diameter probe
= 0.387 for ½"
= 0.757 for ¾"
= 0.945 for 1"
D = inside pipe diameter (inches) Wetted Parts: FPT-6100: 316SS shaft, brass packing and head, carbon steel weld coupling, ¼" SAE flair brass valve; FPT-6200: 316SS shaft, packing and head, carbon steel weld coupling, ½ FNPT Carbon Steel block valves Dimensions For Model FPT-6100: Add 47⁄8" to line size to determine overall length without valves. Add 7½" to line size to determine clearance required to install unit. For Model FPT-6300: Add 8¼" to line size to determine overall length without valves. Add 11½" to line size to determine clearance required to install unit
Sizing Equations 1. Any Liquid: ΔP (in. H2O) = Q2(GPM) x Sf / K2 x D41 x 32.14 2. Steam or Any Gas (steam requires min ΔP of 10" H2O): ΔP (in. H2O) = Q2(lb/hr) / K2 x D41 x ρ x 128,900 3. Any Gas: ΔP (in.H2O)= Q2 (scfm) x SS x (T + 460) / K2 x D41 x P x 16,590
ΔP = differential pressure (in inches H2O)
Q = flowrate
K = flow coefficient (see “how to order”)
D1 = inside diameter of line size (in inches for square and rectangular ducts use): D1 = √(4 x height x width / Π)
P = static line pressure (psia)
T = temperature (in °F)
ρ = density of medium (in pounds per cubic foot)
Sf = Sp. Gr. at flowing conditions
Ss = Sp. Gr. at 15°C (60°F)
NOTE: Use of these equations for liquids yields an accuracy of ±2% of rate. When used for steam, accuracy is ±10% of rate (when steam tables are used). Gas equation yields ±2% of rate accuracy from 21 to 204°C (70 to 400°F) and 0 to 150 psig (when gas is not near its critical point). A ±1% of rate accuracy requires the use of more precise equations which account for shift in K with change in flowrate, gas compressibility, etc. Request a precision flow calibration sheet and please supply the following data: name of fluid, specific gravity, pressure, temperature, inside pipe diameter, viscosity, steam quality, degrees superheat, and ratio of specific heat at constant pressure to that at constant volume (for gas velocities approaching 500 fps).
注: Max. differential pressure shown is for up to 150°C (300°F). Above 150°C (300°F), reduce value by 4% per 56°C (100°F). † Please call Flow Department for questionnaire to size the Pitot tube for your application. Comes with complete operator's manual.