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3.
INSTALLATION
CAUTION
This instrument must be installed by expert
engineer or skilled personnel. The procedures
described in this chapter are not permitted for
operators.
3.1 Piping Design Pre-
cautions
IMPORTANT
Please design the correct piping referring to the
followings to prevent damage for flow tube and
to keep correct measuring.
(1) Location
IMPORTANT
Please install the flow tube to the location where
it is not exposed to direct sunlight and ambient
temperature is –10 to + 60°C (14 to 140°F).
(2) Noise Rejection
IMPORTANT
The instrument should be installed away from
large electrical motors, transformers and other
power sources in order to avoid interference with
the measurement.
(3) Length of Straight Run
To keep accurate measuring, JIS B7554 "Electro
Magnetic Flow Tubes" explains about upstream piping
condition of Magnetic Flow Tubes.
We recommend to our customers about the piping
conditions shown in Figure 3.1.1 based on JIS B7554
and our piping condition test data.
Gate valve
Reducer pipe
fully open
5 D or more 2 D or more
Do not care to 0 D
Tee
90° degrees bent
5 D or more Do not care to 0 D
Figure 3.1.1
Minimum Length of Required Straight Run
NOTE
1. Nothing must be inserted or installed in the
metering pipe than may interfere with the
magnetic field, induced signal voltages, and
flow velocity distribution.
2. These straight runs may not be required on
the downstream side flowmeter. However, if
the downstream valve or other fittings cause
channeling on the upstream side, provide a
straight run of 2 D to 3 D on the downstream
side.
(4) Liquid Conductivity
IMPORTANT
Please avoid to install the flow tube at location
where liquid conductivity is likely to be non-
uniform. Because it is possible to have bad
influences to the flow indication by non-uniform
conductivity when a chemical liquid is injected
from upstream side close to the flow tube. When
this occurs, it is recommended that chemical
application ports are installed on the downstream
side of the flow tube. In case chemicals must be
added upstream side, please keep the pipe
length enough so that liquid is properly mixed.
(BAD)
Upstream side
Figure 3.1.2
Chemical Insertion
3-1
3. INSTALLATION
D: Nominal diameter of flow tube
Expander pipe
Do not care to 0 D
10 D or more
Various types of valves
5 D or more
Do not care to 0 D
10 D or more
(GOOD)
Downstream side
F030102.EPS
IM 1E6D0-01E
2 D or more
2 D or more
F030101.EPS
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