Xylem TX80-Series TURBINE INSERTION FLOW METERS - Manual (Page 4)

INSTALLATION
Page 2
Faster flow causes
meter to read high
FLOW
Distorted flow
profile
BEST
Okay, if no air in pipe
Okay, if no sediment in pipe.
Fitting Installation. TX80-Series meters require special fit-
tings. The meter fitting must first be installed in the pipeline.
Straight pipe of at least ten times the diameter upstream of
the meter and five diameters downstream is strongly recom-
mended in order to achieve proper accuracy. These are
minimum values. As the diagrams on the the next page will
show, you may need more straight run under specific adverse
circumstances.
If you can’t provide enough run to smooth out the turbulence
caused by valves, fittings, and changes in direction, some
decrease in accuracy may result. This does not mean that
the flow meter’s reading is meaningless, however. In some
applications (for instance, where the flow meter is part of a
control system, operating a valve or controlling chemical ad-
dition), a repeatable reading may be more important than a
highly accurate one.
TX80-Series PVC meter tees are supplied with some up-
stream straight pipe. The length provided may be less
than ten diameters upstream and five downstream. It
is not advisable to connect directly to the end of these
fittings with a flow-disturbing device such as a valve or
elbow. If possible, straight pipe should be added to the up-
stream end of these fittings.
A PVC fitting is usually installed by solvent welding. The stain-
less steel and brass meter fittings have female pipe threads,
requiring the appropriate male threaded fittings. Saddle fit-
Caution: Never remove the u-clip retainer
when the pipe is under pressure. Always
remove pressure from the pipe before you
attempt to remove the meter. Removal un-
der pressure may result in damage or serious injury.
tings (size 3” and above) require a hole to be cut in the pipe.
The recommended hole size is 1-3/4”.
Meter Installation. After the meter fitting is installed in the
pipeline, the meter can be installed in the fitting. Press the
meter into the fitting as far as it will go. Retain the meter in
place by inserting the u-pin. The pin can be installed from
either side. It may be necessary to rotate the probe back and
forth slightly to start the pin into the slots on the probe. Slide
the pin in as far as it will go.
DISTORTED FLOWS
POSITIONING THE METER
10X
Diameter Minimum
(See Below)