33
Dival SQD-1 - MT 234-E - 02-2020
EN
MAINTENANCE
7.4
VLA/:: SLAM SHUTH VALVE (fig. 38)
1) Make sure that the slam-shut valve is in closed position;
2) Disconnect the fittings between the slam-shut valve and the downstream pressure connection;
3) Remove the screws tightening the slam-shut valve to the body;
4) Unscrew the plug (20) and the regulation nuts (17) and (18); then, extract the calibration springs (34) and (35) and
the spring supports (12) and (13);
5) Remove the screws (41) and disassemble the cover (2) with the nut (14);
6) Extract from the body (1) the diaphragm assembly consisting of the parts 45, 46, 48, and 49; to separate them,
unscrew the pin (45) from the tightening nut (49);
7) Remove the nut (37) and unscrew the nut (6) and the threaded bush (7) completely;
8) From the upper part, extract the shaft assembly consisting of the parts 9, 66, 19, 4 and 8, the bushes (22) and (23)
and (19), and the shaft (5). Then, unscrew the shaft (5) and the obturator support (4), and remove the spring ring
(9) to disassemble the obturator (19);
9) Remove the screws (40) and disassemble the anchoring assembly consisting of the parts 29, 30, 33, 36, 38, 39, and
43;
10) Remove the screws (53) to disassemble the flange (51);
11) Finally, to disassemble the release button assembly, unscrew the nut (61) and then unscrew the part (58) from the
pin (62).
To reassemble the slam-shut it is possible to carry out the disassembly operations in the inverse order.
Before reassembling the sealing elements (O-rings, diaphragms, etc.), check their integrity and replace them if neces
-
sary
58
65
64
61
62
Blocco LA:
Fig. 38
