
KeyStone DOUBLE FLANGED BUTTERFLY VALVEs
Figure 631 PN16
Repair and maintenance Instructions for DN100 - 500 F631 PN16
double flanged butterfly valves
Safety precautionS
Whenever a valve is being installed or removed
from the pipeline, ensure the line is not
pressurized and any hazardous medium is
drained away.
Before carrying out any maintenance where the
valves are either pnuematically or electrically
actuated be sure to close/isolate the air supply
and exhaust the pressure to the actuator OR
ensure the electrical supply is disconnected by
authorized personnel.
DiSaSSembly inStructionS
1. Turn the disc (2) to the 5° open position.
2. Remove the actuator from the valve, if you
have not already done so.
3. Remove disc screws (8).
4. Remove circlip (14), body plug (13) and plug
O-ring (12) from the shaft (3) at the opposite
end to the actuator end of shaft.
5. Remove shaft bush (10) and shaft seal (11)
from actuator end of shaft.
6. Extract shaft carefully, ensuring not to
scrape shaft against the shaft bore.
Note position of keyway in relation to the
actuator.
7. Twist disc (2) to the fully open position then
roll the disc out of the seat, ensuring not to
damage the disc edge.
8. Collapse seat (4) to the center of the valve
bore at the O-ring housing spigots (shaft
holes) and gently lever one side of the seat
from the flange face, then pull through
when the seat is clear of the bed groove.
Donot use any sharp tools to aid removal
ofseat.
9. Remove upper and lower bearings for
inspection.
10. Thoroughly clean all components and
examine them for excessive wear or
damage. It is recommended that all
‘O’-rings be replaced and all seats, bushes,
plugs etc. are free from damage burrs etc.
maintenance
Routine maintenance or lubrication are not
required.
remoVal inStructionS
If it is necessary to replace components,
thevalve must be removed from the pipe.
1. Partially open valve (5°open).
2. Disconnect any power supplies.
3. Remove flange bolts.
4. Spread flanges and remove valve.
www.valves.emerson.com © 2017 Emerson. All rights reserved.
Vciom-03015-en 16/10

KeyStone DOUBLE FLANGED BUTTERFLY VALVEs
Figure 631 PN16
10
1511 8
3
aSSembly inStructionS
1. Check all components are clean and free of
damage.
2. Fit seat insert O-rings (6) into seat inserts(5)
encapsulated in the seat (300 to 500 only).
3. Collapse the seat (4) and push into the bore
of the valve, aligning the seat inserts(5)
with the shaft bore. Ensuring O-rings are
still in position, locate spigot in shaft bore
at the hub end, then gently push seat (4)
into bedgroove simultaneously on both
sides, working your way up to the top shaft
bore. Then ensure the remaining spigot is
correctly positioned. Inspect the seat(4)
to ensure that it is sitting evenly in the
bedgroove and apply pressure with thumbs
at the spigots to ensure correct fitand that
the seat is sitting evenly on the flange face.
4. Fit shaft bearing (15), shaft seal (11) and
shaft bush (10).
5. Insert the shaft (3) into the neck of the valve
and stop prior to entering the valve bore.
6 5
6. Roll disc (2) into the seat leading with the
disc edge (ensuring not to damage the edge)
with the disc screw holes closest to the neck
of the valve, then twist disc until the shaft
holes are aligned.
7. Push shaft (3) downwards through the
disc(2) into the hub of the valve until the
disc screw holes are aligned counterbore
side towards the disc. A twisting motion
while pushing down will aid with smooth
insertion.
8. Insert disc screws (8) with their O-ring and
tighten to 16 Nm.
9. Push body plug (13) and plug O-ring (12)
into position at the hub end of the valve
shaft bore and lock into position with the
circlip(14).
10. Slowly actuate valve to ensure all
components are free and correctly aligned.
11. Assembly is now complete and the valve is
ready for installation or storage.
Refer to F631 Installation Instructions for
details.
2
© 2017 Emerson. All rights reserved.
2