Badger Meter AHR - Wet Tap, Low Pressure (2 to 36")" - Manual (Page 3)

INTRODUCTION
The Preso patented elliptical design outperforms and provides greater
accuracy than traditional differential pressure flow measurement devices . This
differential pressure flow meter is designed with a series of ports facing the
upstream velocity pressures, as well as flow sensing ports strategically located
ahead of the trailing edge flow separation .
The multi-ported, self-averaging flow element consists of an elliptical shape
with two independent flow sensing chambers . The impact velocity sensing
holes (high pressure) are located along the leading edge and the true static
sensing holes (low pressure) are on the exterior probe side . Model AHR comes
with instrument shutoff valves with provisions to accept a transmitter or
direct indicating meter .
Impact Velocity
Sensing Holes
True Static
Sensing Holes
Figure 1: AHR pressure sensing holes
SPECIFICATIONS
Applications Liquid (without system shutdown), air, gas
Pipe Sizes 2…48 inches (50…1220 mm)
Pressure 150 psi (1034 kPa) maximum
Temperature 150° F (66° C) maximum
Accuracy ±0 .75% of reading
Turndown Ratio 17:1 with no vacuum effect
Standard Components T-type head, 316 SS 1/4" or 1/2" FNPT connection
CS compression fitting with SS ferrule
316 SS isolation ball valve, NPT
CD reducer coupling
CS 3000 lb weld fitting, ASTM A105
CS nipples, schedule 40
316 SS Ellipse sensor
316 SS ID tag with wire
Instrument valves (2 per sensor) 1/4" or 1/2", CS
Reynolds Number Greater than 75,000 maintains most accurate flow measurements
Less than 75,000 consult factory for estimated results
Resonance If greater than 0 .8, use double support .
Table 1: Specifications
User Manual
Page 3 April 2014