3.3 Maintenance of Piping
(1) Cleaning Inside Piping
• Periodically clean and remove any incrustation
and sludge sticking to the inside surface of the
body and shedder bar.
• Be sure to remove any welding scraps, scale
and sludge after welding.
• A chemical reaction sometimes occurs and
causes the measured fluid to harden when
it accumulates in the piping. So, periodically
clean the piping and remove any deposit.
(2) Bypass Piping for Improving Maintainability
Installation of bypass piping is recommended
as shown in the figure below for inspection
and cleaning of the shedder bar and
other parts inside the vortex flowmeter.
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Flow
Bypass shut-off valve
Upstream shut-off valve
Downstream shut-off valve
Vortex flowmeter
3.4 Thermal Insulation of
Cryogenic Type and High
Temperature Type
When the high temperature type and cryogenic type
are used (type of shedder bar: C, D, E), perform
heat insulation by following the precautions below.
■ Installing the Cryogenic Type
Installation of the flowmeter is the same as the
standard type, except that stainless steel nuts and
bolts (ordered separately from Yokogawa) should
be used as a countermeasure for brittleness in low-
temperature applications.
To maintain the vortex flowmeter at an ultra-low
temperature, embed it in cold insulation material
from the body up to the mounting bracket.
■ Maintaining the Cryogenic Type
The cryogenic type uses a shedder bar made of
materials different to those used on a standard
type as a countermeasure for brittleness in low-
temperature applications.
When replacing parts, specify the cryogenic type.
■ Preventing Condensation on the Cryogenic
type
To prevent condensation inside the terminal boxes,
sufficiently seal cable entries.
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<3. Installation>
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IM 01F07A01-01EN
