PIETRO FIORENTINI HBC 975, Руководство пользователя

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67
HBC 975
Use, maintenance and warning manual
SLAM-SHUT VALVE | COMMISSIONING | REV. 00
EN
SPRING CALIBRATION FOR MINIMUM PRESSURE TRIP (IF ANY)
Step Action
1
Open the vent (fig.8.11, ref. 6) to the atmosphere and keep it open for the next steps.
2
Decrease the downstream pressure to the minimum tripping pressure of the slam-shut device by adjusting the
pilot.
NOTE!
Check the pressure referring to the downstream pressure gauge (fig. 8.11, ref. 5).
If the slam-shut valve:
• trips before the expected pressure value: unscrew (anticlockwise) the adjustment ring nut
(15) so as to relieve the spring (17);
• does not trip before the expected pressure value, screw in (clockwise) the adjustment ring
nut (15) so as to further compress the spring (17).
3
Close the vent (fig.8.11, ref. 6).
4
Balance the upstream and downstream pressure of the slam-shut valve using the HP2/2 bypass valve (fig.8.4,
ref. 7.1).
5 Open the vent again (fig. 8.11, ref. 6).
6 Increase the downstream pressure up to the set value by acting on the main regulator.
7 Trigger the slam-shut device by operating the lever in the 3/2 valve (fig. 4.1, ref. 8).
8
Check the correct calibration of the main regulator.
NOTE!
The calibration value must comply with the operating limits specified on the plate.
9 Check the minimum pressure spring for proper calibration by repeating steps 2-3-4 at least three times.
10 Close the vent (fig.8.11, ref. 6).
11
Check the maximum pressure spring for proper calibration by repeating steps 2-3-4 of table 8.41 at least three
times.
Tab. 8.42.