Figure 3.3.1 Mounting Procedure for Union Joint Type
(sizes: 2.5 to 10 mm (0.1 to 0.4 in.))
3.3.2 Nominal Diameter 2.5 mm (0.1 in.) to
40 mm (1.5 in.), Wafer Type
IMPORTANT
Useboltsandnutsincompliancewiththeange
ratings. When stud-type through-bolts are used, be
sure the outside diameter of the shank is smaller than
that of the thread ridge. Be sure to choose a gasket
with inner and outer diameters that does not protrude
inside the piping (refer to Table 3.3.16). If the inner
diameter of the gasket is too large, or outer diameter
ofthegasketistoosmall,uidleakagemayresult.
(1) Mounting Direction
Mounttheowmetersothattheowdirectionoftheuid
to be measured is in line with the direction of the arrow
markontheowmeter.
IMPORTANT
If it is impossible to match the direction of the arrow
mark, the direction of the electrical connection can
be changed. Refer to the applicable user’s manuals
which can be downloaded from our website.
Incasetheuidbeingmeasuredowsagainstthe
arrowdirection,changethevaluefrom“Forward”to
“Reverse”attheparameter[J20:FlowDirection]
(refer to Chapter 8).
(2) Mounting Centering Devices
Tomaintainconcentricityoftheowmeterwiththe
pipes,installcenteringdevicesontheMini-angesof
theowmeter.Usetheappropriatecenteringdevices
accordingtothenominaldiameterandtheangeratings.
(3) Positioning the Flowmeter
Pass two through-bolts through the adjacent holes of
bothangesandpositiontheowmetersothattheMini-
angesandthecenteringdevicescomeinclosecontact
with each other. Pass the other through-bolts through
the other holes (refer to Figure 3.3.2 and Figure 3.3.3).
In case stud-type through-bolts are used, position them
in such a way that the centering devices come in contact
with the bolt threads.
(4) Tightening Nuts
Tighten the nuts according to the torque values for metal
piping in Table 3.3.4. For PVC piping, select an optional
code of GA, GC, or GD, use rubber gaskets and tighten
the nuts to the torque values for PVC piping in Table
3.3.5.
Forpermeableuids(suchasnitricacid,hydrouoric
acid, or sodium hydrate at high temperatures), tighten the
nuts according to the torque values in Table 3.3.6.
CAUTION
ForaowmeterwithuorocarbonPFAlining,itis
possible that the nuts may loosen as time passes,
so tighten them regularly. Be sure to tighten the nuts
according to the prescribed torque values. Tighten
them diagonally with the same torque values, step by
step up to the prescribed torque value.