GE ApexPro T9, Руководство по установке

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Model T9 Ultrasonic Flow Transducer Installation Guide 5
Chapter 2. Installing Pipe Nozzles
2.3 Selecting and Marking the First Nozzle Location
CAUTION! Correct nozzle alignment is critical to the successful operation of the flowmeter; therefore, all
marking, positioning and welding operations must be carried out with the utmost attention to
accuracy. Unless otherwise stated, dimensional positioning of the nozzles must be held to a
tolerance of

1/16 in. (1.6 mm) relative to each other and with respect to the pipe centerline. the
angular tolerance must be held to

1 O
.
All hole cutting in process piping must be performed using hot tapping equipment.
1. For optimum performance, you should select a location that has undisturbed straight run pipeline at least 10 pipe
diameters upstream and 5 pipe diameters downstream from the point of measurement. Undisturbed pipe means
avoiding sources of turbulence such as valves, flanges, elbows; avoiding swirl; and avoiding disturbed flow
profiles.
2. We recommend that you install the nozzles on a diameter as near as possible to the horizontal plane (i.e., 3 o’clock
and 9 o’clock) as shown below.
10D 5D
D
Flow
End View