Badger Meter ASF - Steam (2 to 48")" - Manual (Page 3)

INTRODUCTION
The patented Preso 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 ASF comes
with instrument shutoff valves with provisions to accept a transmitter or direct
indicating meter .
True static
sensing holes
Impact velocity
sensing holes
Figure 1: ASF pressure sensing holes
SPECIFICATIONS
Applications Steam
Pipe Sizes 2…48 inches (50…1220 mm)
Pressure Vary per flange ratings
Temperature Vary per flange ratings
Accuracy ±0 .75% of reading
Turndown Ratio 17:1 with no vacuum effect
Standard Components T-type head, 316 SS 1/2" FNPT connection
CS compression fitting with SS ferrule
CS 3000 lb weld fitting, ASTM A105
316/316L SS Ellipse sensor
316 SS ID tag with wire
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 per ASME PTC 19 .3 .
Table 1: ASF specifications
User Manual
Page 3 April 2014