ARI Armaturen STEVI 451 EN - Manual (Page 14)

Page 14 Rev. 0040306000 0410
Operating and installation instructions
3-way control valves - STEVI
®
450 / 451
DN125v-150v
- Dismantle as item 7.1.3.
- Loose nuts (pos. 11).
- Detach bellows assembly (pos. 20) incl.
stuffing box housing (pos. 39).
- Drive pin (pos. 33) out with a drift.
- Unscrew plug (pos. 40) from adapter (pos. 38).
- Loose nuts (pos. 29).
- Detach bellows assembly (pos. 20).
- Loose nuts (pos. 20.8).
- Detach stuffing box housing (pos. 20.13).
- Extract stem/bellows unit (pos. 20.3) from the
bellows housing (pos. 20.1).
- Drive pin (pos. 6) out with a drift.
- Unscrew stem adapter (pos. 38).
- Bolt new parts together, drill and pin them.
- Replace 2 gaskets (pos. 20.6) and each
1 gasket (pos. 27, 9).
- Assemble in reverse order .
(For tightening torques refer to item 7.3.)
- Secure with nuts (pos. 29 and 20.8) and
tighten them crosswise.
(For tightening torques refer to item 7.3.)
- Tighten sleeve nut (pos. 20.16) gradually up to
tightness of the stuffing box packing
(pos. 20.10).
ATTENTION !
- Ensure that the torsion lock is
correctly positioned when inserting
new stem/bellows unit. Introduce the
straight pin (pos. 20.9) into the
torsion lock groove.
Make sure it runs smoothly!
Fig. 19:
Series 451 DN125v-150v
with diverting plug