Yokogawa EJX438B - Manual (Page 23)

<4. Installation>
4-5
IM 01C27H01-01EN
F0408.ai
Ring
Diaphragm
Pressure-detector
section
Gasket
Mating flange
Spiral gasket
Figure 4.8 Mounting to Process Flange
IMPORTANT
• Confirm that there is no gap between the ring
and the process-detector section after they
are mounted on the process flange. A gap
can lead to a sudden, explosive release of
process fluids.
• When mounting or removing the ring,
take care not to tilt the pressure detector
downward as the ring can slip off and cause
injury.
• When re-mounting the ring, use the new
spiral gasket as shown in below table.
Table 4.1 Spiral Gasket for Pressure Detector
Section Side*
Part number Size Description
F9350SV ш100Чш120Чt4.5 For 3-inch flange
F9970XF ш100Чш120Чt4.5 For 3-inch flange**
F9350ST ш70Чш90Чt4.5 For 2-inch flange
F9970XD ш70Чш90Чt4.5 For 2-inch flange**
F9346ZH ш60Чш75Чt4.5 For 1 1/2-inch flange
F9970XB ш60Чш75Чt4.5 For 1 1/2-inch flange**
*: Material; 316SST (Hoop), PTFE Teflon (Filler)
**: For oil-prohibited use (Option code: /K1, /K5)
4.5 Affixing the Teflon Film
The FEP Teflon option includes a teflon film and
fluorinated oil.
Before mounting the diaphragm seal to the process
flange, affix the teflon film as follows:
IMPORTANT
1) Position the diaphragm seal so that the
diaphragm is in a upward position.
2) Pour the fluorinated oil on the diaphragm
and gasket area covering it completely
and evenly. Be careful not to scratch the
diaphragm or change the its shape.
3) Affix the teflon film over the diaphragm and
gasket area.
4) Next, carefully inspect the cover and try
to identify any entrapped air between
the diaphragm and the teflon film. The
air must be removed to ensure optimum
performance. If air pockets are present, use
your fingers to remove the air by starting at
the center of the diaphragm and work your
way out.
5) Position the gasket on the Teflon film.
6) Mount the transmitter onto the process
flange.
Teflon film
Diaphragm
Fluorinated oil
[PART No.: F9145YN]
Gasket area
Diaphragm seal
PART No.
F9347XA
F9347YA
Process flange size
For 3inch (80 mm)
For 2inch (50 mm)
F0409.ai
Figure 4.9 Affixing the Teflon Film
4.6 Rotating Transmitter Section
WARNING
Intrinsic safe type transmitters must be, as a rule,
do not rotate transmitter section if it is powered.
In case you need to rotate when the transmitter
is powered, using gas detector and confirm no
existence of explosive gas before rotating.