Pipe Problems - GE UTX878 Ultrasonic User Manual

Pipe Problems

Error Codes and Diagnostics
Pipe-related problems may result either from a failure to observe the
installation instructions, as described in Chapter 1, Installation, or
from improper programming of the meter. By far, the most common
pipe problems are the following:
1. The collection of material at the transducer location(s).
Accumulated debris at the transducer location(s) will interfere
with transmission of the ultrasound signals. As a result, accurate
flow rate measurements are not possible. Realignment of the
measurement point or transducers often cures such problems.
Refer to Chapter 1, Installation, for more details on proper
installation practices.
2. Inaccurate pipe measurements.
The accuracy of the flow rate measurements is no better than the
accuracy of the programmed pipe dimensions. Measure the pipe
wall thickness and diameter with the same accuracy desired in the
flow rate readings. Also, check the pipe for dents, eccentricity,
weld deformity, straightness and other factors that may cause
inaccurate readings. Refer to Chapter 2, Programming Site Data,
for instructions on programming the pipe data.
3. The inside of the pipe must be relatively clean. Excessive build up
of scale, rust or debris will interfere with flow measurement.
Generally, a thin coating or a solid well-adhered build up on the
pipe wall will not cause problems. Loose scale and thick coatings
(such as tar or oil) will interfere with ultrasound transmission and
may result in incorrect or unreliable measurements.
March 2004
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