PIETRO FIORENTINI HBC 975, Руководство пользователя

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65
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 Disconnect the sensing line between pressure switch and line.
2
Use an external pressure source connected to the pressure switch sensing line to inject pressure into the
pressure switch head.
NOTE!
Increase the pressure up to the slam-shut device reset value.
3 Trigger the slam-shut device by operating the lever in the 3/2 valve (fig. 4.1, ref. 8).
4
Release the pressure from the pressure switch up to the tripping value of the slam-shut valve.
NOTE!
The calibration value must comply with the operating limits specified on the plate.
5
NOTE!
Check the pressure by referring to the additional pressure gauge on the external source used
for calibration.
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).
6
Check the minimum pressure spring for proper calibration by repeating steps 2-3-4 at least three times.
NOTE!
The calibration value must comply with the operating limits specified on the plate.
7
Check the maximum pressure spring for proper calibration by repeating steps 2-3-4 of table 8.39 at least three
times.
NOTE!
The calibration value must comply with the operating limits specified on the plate.
8 Disconnect the external pressure source from the pressure switch sensing line.
9 Reconnect the sensing line between pressure switch and line.
Tab. 8.40.