ARI Armaturen STEVI 471 EN - Manual (Page 11)

Rev. 0040305000 0410 Page 11
Operating and installation instructions
Straight through control valves - STEVI
®
470 / 471
DN125v-150v
- Loose nuts (pos. 11).
- Detach bellows assembly (pos. 22) incl. stuffing
box housing (pos. 24).
- Slacken sleeve nut (pos. 22.16) by about one
turn.
- Loose nuts (pos. 39).
- Lift bellows housing (pos. 22.1).
- Drive spring pin (pos. 36) out with a drift.
- Unscrew stem adapter (pos. 35) with plug
(pos. 3).
- Loose nuts (pos. 22.8).
- Detach stuffing box housing (pos. 22.13).
- Extract stem/bellows-unit (pos. 22.3) from the
bellows housing (pos. 22.1).
- Bolt new parts together and drill them.
- Replace 2 gaskets (pos. 22.6), 1 gasket
(pos. 37) and 1 gasket (pos. 8).
- Assemble in reverse order.
- Secure with nuts (pos. 10, 39 and 22.8) and
tighten them crosswise.
(For tightening torques refer to item 7.3.1)
- Tighten sleeve nut (pos. 22.16) gradually up to
tightness of the stuffing box packing (pos. 22.10).
ATTENTION !
- Ensure that the torsion lock is
correctly positioned when inserting
new stem/bellows unit. Introduce the
grooved pin (pos. 20.9) into the
torsion lock groove.
Make sure it runs smoothly!
Fig. 15: Series 471
DN125v-150v