Bray Triple Offset - Manual (Page 12)

10 O & M
ASME CLASS
150 & 300
A D i v i s i o n o f B r a y I n t e r n a t i o n a l , I n c .
The Ultimate Critical Service Triple Offset Valve
O p e r a t i o n a n d M a i n t e n a n c e M a n u a l
seat. Check each time that the disc seal ring makes
full contact without torquing into the seat. Attention
should be paid in the closing stroke that the seat does
not scratch thedisc seal ring. This will allow thedisc
seal ring and seat to be properly aligned.
13. Close the valve. Tighten at least four screws in the
seal retainer to prevent the disc seal ring from fur-
degrees. Tighten all disc seal ring retainer screws
(C5) using a cross bolting technique, to the torque
Table 3 (Pg. 12).
14. Re-apply lubricant to the sealing surfaces of the
valve. Reinstall actuation device and test the valve.
9.3 Disc seal ring replacement
Refer to parts diagram for parts identification by
reference numbers. (Pg. 7)
It is highly recommended that both the body seat (replace-
able) (B1) and disc seal ring (C2) be replaced at the same
time. However, individual components are not matched
in pairs; and may be replaced separately if desired.
!
CAUTION
Exercise extra care when handling the body seat (replace-
able) anddisc seal ring to avoid damage to the sealing
surfaces.
Thedisc seal ring (C2) may only be replaced in two ways:
without removing the seat (B1); or replacing the disc seal
ring (C2) with the seat (B1) removed.
To remove the disc seal ring (C2) without removing the
seat (B1), the actuation device must be removed and the
valve oriented in a manner that allows access to both
sides.
-
Disc disc seal ring replacement with the body
seat (replaceable) in the valve:
1. Remove valve from the pipeline. Remove the actua-
tor from the valve.
2. Clean the surface of the valve with compressed air,
blow out all debris around the disc seal ring retainer
(C4) and clean out the hex sockets of the disc seal
ring retaining cap screws (C5).
3. Loosen all disc seal ring retaining cap screws (C5),
but leave them in the valve with thedisc seal ring
retainer (C4) attached to the disc (C1).
4. Using a wrench, rotate the valve stem (D1) coun-
terclockwise past the fully open position far enough
so the disc is in a position to allow disc seal ring
retainer and disc seal ring removal (C2). Be careful
not to over-rotate the stem (D1) to the point where
the disc seal ring (C2) or disc edge (C1) contact the
body (A1). Make sure the packing gland retainer nuts
(H7) are tight enough to prevent the valve stem (D1)
from rotating on its own under the eccentric weight
of the disc (C1).
5. Remove the disc seal ring retaining cap screws (C5)
and lock washers (C6), and extract the disc seal ring
retainer (C4) and the disc seal ring (C2).
6. Rotate the disc (C1) as necessary to access the seal
face on the disc (C1). Using soft tools and suitable
wire brush, carefully clean any remnants of old gasket
and foreign matter from the face of the disc (C1).
Blow out all threaded holes and the gasket groove
with compressed air.
7. Rotate the disc (C1) to it’s previous position to fa-
cilitate installation of the disc seal ring (C2). Place
a new disc seal ring gasket (C3) into the groove on
the disc face (C1). The mating side of the disc seal
ring gasket can be lightly greased to improve reten-
tion in the groove. Place the disc seal ring (C2) onto
the disc (C1) making sure the alignment line on the
disc seal ring matches the locating dimple in the
disc face. Place the disc seal ring retainer (C4) over
the disc seal ring. Apply anti-seize compound to the
disc seal ring retaining cap screws (C5). Install all
retaining cap screws (C5) with lock washers (C6).
The cap screws (C5) should be fully threaded into the