Baker Hughes Panametrics AquaTrans AT600, Руководство пользователя

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AquaTrans™ AT600 User’s manual 7
Chapter 1. General installation instructions
1.7 Choosing a clamp-on fixture/transducer location
For a given fluid and pipe, the accuracy of AT600 depends on the location and alignment of the transducers. In
addition to accessibility, when choosing a transducer location, follow these guidelines:
• Position the clamp-on fixture(s) and transducer system so that there are at least 10 pipe diameters of straight,
undisturbed flow upstream and 5 pipe diameters of straight, undisturbed flow downstream from the
measurement point (see figure 7 below). Undisturbed flow means avoiding sources of turbulence in the fluid
such as valves, flanges, expansion joints, elbows, swirl, and cavitation.
• Locate the transducers on a common axial plane along the pipe (see figure 8 below). The transducers should
be mounted on the side of the pipe, rather than the top or bottom, because the top of the pipe tends to
accumulate gases and the bottom tends to accumulate sediment. Either condition may cause excessive
attenuation of the ultrasonic signal. There is no similar restriction with vertical pipes, as long as the flow
direction is upward to prevent free falling of the fluid in a partially filled pipe.
Figure 7: AT600 clamp-on fixture/transducer location
Figure 8: Good and bad transducer locations7
Flow direction
DOWNSTREAM
5 X D (min)
UPSTREAM
10 X D (in.)
D
Good
Bad
Good
Good
Flow
Flow
Flow
Bad