PIETRO FIORENTINI HBC 975, Manual

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66
HBC 975
EN
Use, maintenance and warning manual
SLAM-SHUT VALVE | COMMISSIONING | REV. 00
8.5.2.2 - CALIBRATION PROCEDURE WITH MAIN REGULATOR
11
13
17
15
10
16
Fig. 8.13. Calibration of pressure switches Mod.100
SPRING CALIBRATION FOR MAXIMUM PRESSURE TRIP
Step Action
1
By acting on the main regulator, increase the downstream pressure up to the tripping value of the slam-shut
valve, to check for proper calibration.
NOTE!
Check the pressure referring to the pressure gauge (fig. 8.11, ref. 5) downstream of the main
regulator.
If the slam-shut valve:
• trips before the expected pressure value: screw in (clockwise) the adjustment ring nut (13)
so as to further compress the spring (11);
• does not trip at the expected pressure value: unscrew (anticlockwise) the adjustment ring
nut (13) so as to relieve the spring (11).
2
By opening the vent (fig.8.11, ref. 6), decrease the pressure in the downstream section to the calibration value
of the main regulator.
3 Close the vent (fig.8.11, ref. 6).
4 Trigger the slam-shut device by operating the lever in the 3/2 valve (fig. 4.1, ref. 8).
5
Repeat steps 2-3-4 at least three times.
NOTE!
The calibration value must comply with the operating limits specified on the plate.
Tab. 8.41.