20
MT 235 – EN ed.2015 (Rev.A)
5.5
COMMISSIONING THE REGULATOR PLUS IN-LINE MONITOR DIVAL 500 WITH EMBEDDED
SLAM-SHUT
VALVE LA/…
If on the line there is a relief valve, refer to par. 4.1 to check it.
Figure 21: M Active Regulator Diagram (internal sensing line)
Figure 22: M Active Regulator Diagram (internal and external sensing line)
Check and record the tripping of the slam-shut device 7 as follows:
A)
For the slam-shut devices connected to the downstream piping through the "push" three-way switch valve
11
, proceed as
follows (fig. 19):
1.
Connect a controlled auxiliary pressure C to the "push" valve;
2.
Stabilize this pressure at the calibration value set for the regulator;
3.
Completely press the knob 1 of the "push" three-way valve;
4.
Restore the slam-shut device by means of the suitable bushing;
5.
Keep the knob 1 pressed and:
For the safety devices tripping in case of maximum pressure: slowly increase the auxiliary pressure and
verify the tripping value. If necessary, increase the tripping value by rotating clockwise the adjustment ring
nut 549; rotate it counter-clockwise to decrease the tripping value.
For the safety devices tripping in case of pressure increase and decrease: slowly increase the auxiliary
pressure and record the tripping value. Restore the pressure to the calibration value of the regulator and
perform the block restoration operation. Check the tripping due to pressure decrease by slowly reducing
the auxiliary pressure. If necessary, increase the values for tripping in case of pressure increase or
decrease by turning clockwise the ring nuts 549 or 548, respectively. Proceed inversely to decrease the
tripping values.
Make sure that the operation is correct by repeating the procedure for at least 2-3 times
