Ellipse® Pitot Tube Meter AHS Annular Threaded Hot Tap Steam Meter PTT-UM-00513-EN-02 (April 2014) User Manual
Ellipse® Pitot Tube Meter, AHS Annular Threaded Hot Tap Steam Meter CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
User Manual 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.
Ellipse® Pitot Tube Meter, AHS Annular Threaded Hot Tap Steam Meter PIPE ORIENTATION AND SENSOR MOUNTING FLOW Field Weld Preferred installation Allowable plane of installation Figure 2: Horizontal pipe installation 5° Max. 5° Max. OR F L O W W F L O Field Weld NNOTE: Preferred flow direction for steam is upward. Illustration represents installation for upward flow.
User Manual INSTALLATION INSTRUCTIONS, SINGLE SUPPORT 1. Choose the proper location to install the AHS Ellipse using AGA/ASME standards (or equivalent). See “Preso Ellipse Location Instructions” on page 7. 2. Grind the surface of the pipe where the AHS Ellipse is to be inserted to provide a clean area for welding. 3. Weld the supplied weld-o-let to the pipe using standard codes for your application (1/16" weld gap recommended). Take care to protect the threads during the welding process. 4.
Ellipse® Pitot Tube Meter, AHS Annular Threaded Hot Tap Steam Meter INSTALLATION INSTRUCTIONS, DOUBLE SUPPORT 1. Follow steps 1 through 7 in “Installation Instructions, Single Support” on page 5. At 180° from and on the same plane as the previously drilled hole, grind the surface of the pipe to provide a clean area for welding. Drill a hole and deburr, especially on the inside of the pipe. The hole used for the double support should be sized according to Table 3 on page 6. 2.
User Manual LOCATION INSTRUCTIONS Straight pipe requirements: Accuracy is affected by the piping configurations due to the disturbances of the flow profile. A fully developed symmetrical flow profile is achieved with the minimum upstream and downstream recommended lengths.
5 6 78 91 0 0 0 0 0 4 3 2 USGPM NOTE: 2" THRU 10" CURVES ARE FOR SCH. 40 PIPE 12" AND ABOVE ARE FOR SCH. STD. PIPE 2 2 1 .2 .3 1 .9 .8 .7 .6 .5 .4 3 2 4 3 4 6 5 10 9 8 7 5 6 7 8 91 0 20 IN S 2 O 90 80 70 60 50 40 30 ∆P – CH E OF H ANNULAR ELLIPSE 100 3 4 5 6 78 9 1 0 0 2 2" 2.5" 3 4 3" 3.5" 4" 5 6 78 9 1 0 0 0 5" 6" 2 3 8" 4 10" 5 6 7 8 91 0 0 0 0 12" 16" 20" 14" 18" 24" 30" WATER 60° F FLOW CURVE Figure 8: Flow curve Control. Manage. Optimize.
