5 Selection of the Measuring Point FLUXUS G60x
UMFLUXUS_G6V4-2EN, 2011-03-29 23
The following requirements must be met at the measuring point:
• no material deposits in the pipe
• no accumulation of liquid (condensate), e.g. before orifice plates or at pipe sections lo-
cated at lower levels
5.2 Undisturbed Flow Profile
Some flow elements (elbows, slide valves, valves, control valves, pumps, reducers, dif-
fusers, etc.) distort the flow profile in their vicinity. The axisymmetrical flow profile needed
for correct measurement is no longer given. A careful selection of the measuring point
helps to reduce the impact of disturbance sources.
It is most important that the measuring point is chosen at a sufficient distance from any
disturbance sources. Only then it can be assumed that the flow profile in the pipe is fully
developed. However, measuring results can be obtained even if the recommended dis-
tance to disturbance sources can not be observed for practical reasons.
Tab. 5.1: Recommended transducer mounting position
horizontal pipe
Select a measuring point where the transducers can be mounted on the side of the
pipe, allowing the sound waves to propagate in the pipe horizontally. Thus, solid or liq-
uid deposits on the bottom of the pipe will not influence the propagation of the signal.
correct : disadvantageous: