Installation; Fitting Installation, Distorted Flows, Meter Installation, Orienting The Meter; Distorted Flows, Orienting The Meter - Seametrics TX800 Series Instructions Manual

INSTALLATION

Fitting Installation
TX800-Series meters require special fittings. 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 recommended 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
addition), a repeatable reading may be more important than
a highly accurate one.
TX800-Series PVC meter tees are supplied with some
upstream 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 upstream end of these
fittings.
Faster flow causes
meter to read high
Distorted flow
profile
FLOW
10X
Diameter Minimum
Distorted Flows
A PVC fitting is usually installed by solvent welding. The
stainless steel and brass meter fittings have female pipe
threads, requiring the appropriate male threaded fittings.
Saddle fittings (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. After noting the direction of the
flow arrow, press the meter into the fitting as far as it will go.
Retain the meter in place by inserting the U-clip. 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.
Horizontal (3 o'clock or 9 o'clock position) is the preferred
installation orientation, since it improves low-flow performance
and avoids problems with trapped air and sediment. (See
Orienting the Meter diagram below.) Bottom (6 o'clock), top
(12 o'clock), and vertical pipe installations are all acceptable if
required by the piping layout.
5X
Diameter Minimum
Sea m e tr i cs • 2 5 3. 872 . 0 2 8 4 • w w w . s e a me t r i c s .c o m
TX800 SERIES INSTRUCTIONS
Fair
Unacceptable if pipe
contains air
Fair
Unacceptable if pipe
contains sediment
Orienting the Meter
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 under pressure
may result in damage or serious injury.
Best
Position
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