47
TROUBLESHOOTING
A: NO MEASURE AT ALL
1. Are you absolutely certain that the piping is
completely filled?
□
2. Can you exclude gas load on the medium?
Is a pump close by?
If there is gas load:
• Are the transducers installed at the 10 AM
or 2 PM position on the horizontal pipe?
• If there is gas load on the medium, is there
an option of mounting the transducers to a
vertical pipe? If yes, mount the transducers
to a vertical pipe.
□
3.
What is the solid particle content of the fluid? □
4.
Are you absolutely certain of the wall thick
-
ness? Check the piping for the presence
of engraved information that may be of
relevance. Hot water piping is subject to the
formation of lime deposits that may propagate
the deposit of solid particles of fluid with high
content. Use a wall thickness meter. You can
purchase a wall thickness meter from GPI.
Check the wall thickness entry on the device.
□
5. Did you enter the
outer diameter
of the pipe,
or its
circumference
? Check the correspond
-
ing values once again.
□
6.
Have you selected the correct piping mate
-
rial? Are you certain the
piping is not lined
?
When taking measurements on a pipe made
of concrete you must presume that this piping
does not have sound conducting properties.
Check the setup values once again.
□
7. Does the ultrasonic transducer match the
application with regard to pipe dimensions
and medium temperature? Is the temperature
of the fluid within permitted limits? Did you
select a suitable ultrasonic transducers for
the application with regard to the pipe dimen-
sions? Once again, verify that you selected
the correct ultrasonic transducer and that it
is setup.
□
8. Which transducer mounting mode did you se-
lect? Standard is the V-mode. If you selected
the W-mode, you should firs
t try the V-mode.
□
9.
Verify the proper transducer distance. Take
the measurements at the transducer faces.
When using a spacer bar, check the number
of holes between the transducer mounting
positions.
□
TROUBLESHOOTING
A: NO MEASURE AT ALL
10.
Does the piping have a thick paint coating?
If yes, try to remove the paint at the position
where you are planning to install the ultrasonic
transducers using sand paper. Never take any
measurements on piping insulation, no matter
what type of material is involved.
□
11.
Did you apply an appropriate film of acoustic
coupling gel (Magnalube) to the transducer
faces? Small transducers (types QMP-F10 and
F21) need approximately 1.2 inches, whereas
the large transducer (QMP-F05) requires ap
-
proximately 2.4 inches of coupling gel.
□
12.
Do the transducers apply adequate pressure
on the piping?
□
13. Are the transducers that are mounted without
spacer bar precisely aligned along a common
axis on the piping?
□
14. Are there sources of strong disturbance such
as transformers,electrical drives, or sources of
vibration in the immediate area of measure-
ment?
□
15. Use the Z-mode for installation if all of your
efforts did not yield a satisfactory result. Setup
your device accordingly. You might also try to
test your equipment on a different piping sec
-
tion that is close by in order to find out whether
or not you can perform a measurement. Check
all measuring leads for damage.
□
B: IMPRECISE MEASUREMENT RESULTS
1. Did you observe the corresponding upstream
and downstream distances? The quality of
measurements will deteriorate in propor-
tion to shorter upstream and downstream
distances.
□
2 . Did you perform a zero calibration after
having closed a stop valve on piping?
□
3 . Check the setup values with regard to the:
• Pipe outer diameter
• Wall thickness
• Piping material
• Transducer distance
□