Diaphragm Seals - ABB 2600T-Serie Bedienungsanleitung

6 Diaphragm seals

6.1 Seals handling
— Diaphragm seals equipped transmitters require a
particular attention during handling and installation to
avoid damaging the device.
— For capillary equipped transmitters (gauge or differential)
avoid lifting the device by gripping the capillary.
— Avoid excessively bending the capillary, the maximum
bending radius is12,5 cm (5 inches).
— The diaphragm surface is delicate and could be damaged.
Therefore, leave the diapgragm protection covers in place until
the final installation and when the ptotection has been
removed, avoid placing the seal with the diaphragm in contact
with a hard surface.
6.2 Seals installation
Before proceeding with the installation be sure that the
diaphragm seal MWP (Maximum Working Pressure limit) is in
compliance with the mating process connection.
The diaphragm seal MWP is written on the transmitter main
nameplate (MWP for differential pressure transmitters, OVP for
gauge and absolute pressure transmitters). Check that the fill
fluid type and temperature limit is in compliance with your
environmental/process conditions. The transmiiter has been
delivered with wetted materials according to the model numer
specified on the nameplate. Before proceeding with the
installation consider wetted material process compatibility.
If you are installing a diaphragm seal which requires a gasket
(S26CN, S26F, S26J, S26M, S26P, S26R, S26S, S26U, S26V,
S26W ) be sure to use a suitable gasket for your processfluid,
check that the temperature and pressure limit are compatible
with your application.
Properly position the gasket so that it does not tpress down
the diaphragm. A gasket not properly installed may affect the
transmitter measurement. When installing flushing rings make
sure that the gasket is properly aligned on the gasket sealing
surface.
6.3 Bolt torquing
During the installation of flanged or wafer type seals the bolts
have to be torqued to the specific flange and gasket
requirements. The torque requirement is a function of the
gasket and bolts material.
6.4 Vacuum application consideration
When installing remote diaphragm seals in application working
below the atmospheric pressure, check that the fill fluid curves
are in compliance with your application. The transmitter must
be located below or at the bottom process tap. In case of
doubts please refer to the integral instruction manual that can
be downloaded at www.abb.com/pressure or refer to your ABB
Instrumentation dealer.
16 SOI/266-XC Rev. D | 2600T Series Pressure transmitters
6.5 Wafer (pancake) seals (model S26W)
Wafer seals installation requires the user to apply a blind flange
to connect the seal to the process, the type, size and material
of the blind flange must be in compliance with the mating
process connection counterflange.
6.6 Off-line threaded and flanged seals
(models S26T and S26M)
The upper and lower housing is preassembled at the factory.
When connecting the S26T off-line threaded seal to the
process pipe, do not overtighten the seal. Torque value should
be in compliance with ANSI B1.20.1 or applicable torque
requirements for pipe connections.
In case the lower housing needs to be disassembled from the
upper housing, when riassembling be sure to replace the
gasket with a new gasket of the same tipe (see spare part list
for part number).
The bolts should be thighten to 25 Nm.
6.7 Saddle and Socket seals (model S26V)
Saddle and Socket seals are delivered with all the parts
necessary to perform a correct installation.
The lower housing has to be welded to the process pipe.
When welding the lower housing to the process pipe, the upper
housing has to be removed.
The upper housing can be installed on the lower housing whe it
has cooled down.
Before positioning the upper housing be sure that the gasket
has been properly placed in its seat.
Bolts torque value for socket and saddle seal is 20 Nm.
6.8 Sanitary seals (model S26S)
ABB sanitary seals may be supplied with a 3A symbol which is
printed on the seal body. To properly install 3A approved seals
please refer to the integral version of the instruction manual that
can be downloaded from www.abb.com/pressure.
6.9 Threaded seals for Pulp&Paper (model S26K)
Threaded seals for Pulp&Paper should be installed considering
the proper torquing value which is a function of the thread type
6 Diaphragm seals