ARI Armaturen STEVI 451 EN - Manual (Page 16)

Page 16 Rev. 0040306000 0410
Operating and installation instructions
3-way control valves - STEVI
®
450 / 451
DN125v-150v
- Unscrew seat ring (pos. 2 bottom) and renew or
recondition.
- Slacken nuts (pos. 24) by about 2-3 turns.
- Extract and replace plug (pos. 3) and stem
(pos. 5).
- Assemble in reverse order.
(For tightening torques refer to item 7.3.)
Changing the top seat ring:
- Dismantle seat ring, plug and stem as described
above.
- Loose nuts (pos. 11).
- Detach stuffing box housing (pos. 39).
- Unscrew seat ring (pos. 2 top) and renew or
recondition.
(For tightening torques refer to item 7.3.)
- Replace gasket (pos. 9).
- Assemble in reverse order.
(For tightening torques refer to item 7.3.)
- Secure with nuts (pos. 11) and tighten them
crosswise.
(For tightening torques refer to item 7.3.)
(bottom)
(top)
Fig. 21:
Series 450 DN125v-150v
with mixing plug