83
DIV
AL 600
Use, maintenance and warning instructions
MEDIUM PRESSURE REGULATOR
|
COMMISSIONING
|
REV. A
EN
SPRING CALIBRATION FOR MAXIMUM PRESSURE TRIP
Step
Action
1
Increase the downstream pressure to the tripping value of the slam-shut valve, connecting an external pres-
sure source to the bleed cock (fig. 8.16, ref. 6) placed on the downstream pipe, making sure to open an addi-
tional bleed cock (fig. 8.21, ref. 18).
NOTICE!
Check the pressure referring to the downstream pressure gauge (fig. 8.16, ref. 5).
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 (anti-clockwise) the adjustment ring
nut (13) so as to relieve the spring (11).
2
Decrease the pressure of the downstream section by opening the additional bleed cock (21, ref. 18) to bring it
up to the calibration value of the main regulator.
3
Close the additional bleed cock (fig. 8.21, ref. 18).
4
Resetting the slam-shut valve by turning the reset knob (16).
5
Repeat steps 1-2-3-4 at least three times, observing the operating limits indicated on the nameplate.
6
Disconnect the external pressure source from the bleed cock (fig. 8.16, ref. 6).
Tab. 8.48
Summary of Contents for Dival 600
Page 156: ...TM0023ENG...
