11
Dival SQD-1 - MT 234-E - 02-2020
EN
INSTALLATION
The installation of a multiple plug on a plant has its aim in in taking from a single point all the pressure impulse signals
that go to the different reduction- safety devices and to their accessories.
The regulator must be installed in the line with the arrow on the body pointing in the gas flow direction.
It is indispensable for good regulation for the position of the downstream pressure take-offs and the speed of the gas
at the take-off point respect the value given.
The regulator, when used in gas pressure reduction stations, has to be installed at least according to the requirements
set forth by the standards EN 12186 or EN 12279. All points for possible gas relief due to possible breaks of sensors/
diaphragms are to be conveyed according to standards EN 12186 or EN 12279.
The following is recommended so as to prevent the accumulation of impurities and condensate in the lines of the
pressure take-off.
a)
The lines themselves must slope down towards the downstream piping with a slope of about 5-10%;
b)
The connectors on the piping must always be welded on the top of the piping itself and there must be o burr
or inward protrusions in the hole in the piping.
The speed of the gas must not exceed the following values in the piping down-stream from the regulator:
Vmax = 15 m/s
ATTENTION!
2.3
DOWNSTREAM VOLUME REQUIRED FOR INSTALLATION
In the case of a service regulator of the ON-OFF type (stopping or starting of burners), you should remember that
though the SQD- 100 apparatus is classified as being of the fast reaction type, it requires an appropriately dimensioned
volume of gas between the apparatus itself and the burner so as to partly absorb the pressure swings caused by fast
flow rate variations.
3.0 MODULARITY
The modular-type conception of SQD-1 regulators means that it is also possible to fit the slam-shut incorporated with
the body itself even after the installation of the regulator.
3.1
LA/.. INCORPORATED SLAM SHUT
This is a device (fig. 7 and 8) which immediately blocks the gas flow if, because of some failure, the downstream pres
-
sure reaches the point set for its intervention, or if it is actuated manually.
Wait the SQD-1 pressure regulator, the slam-shut be incorporated on both the service regulator or on the in-line mo
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nitor. Three versions (LA/BP, LA/MP and LA/TR) are available depending on the intervention pressure ranges
The main features of the slam-shut device are as follows:
•
Design pressure PS: up to 20 bar;
•
Intervention for pressure increase and/or decrease;
•
Intervention accuracy AG: ± 5% of the set point for pressure increase (based on setting-pressure); ± 15% of
the set point for pressure drop (based on setting-pressure);
•
internal by-pass device;
•
manual button-operated actuating device.
N.B. WE RECOMMEND NOT TO PUT ON/OFF VALVES ON THE IMPULSE TAKE-OFFS
ATTENTION!
