Emerson Keystone 990 Technical Document

KEYSTONE FIGURE 990/991 BUTTERFLY VALVES
InstallatIon, operatIon and maIntenance InstructIons
1 INTRODUCTION
Keystone Figure 990/991 is a rubber lined
butterfly valve suitable for use on all fluids
except those designated as ‘unstable’
according to the Pressure Equipment Directive,
97/27/EC.
Figure 990 is available in sizes 25 mm to
300mm and has a maximum working pressure
of 10 barg over a temperature range of -10°C
to+150°C. Figure 990 has a cast iron body of
two piece design which enables the use of a
one piece disc stem.
Figure 991 is available in sizes 25 mm to
150mm and has a maximum working pressure
of 10 barg over a temperature range of -10°C
to +150°C. Figure 991 has a cast stainless
steel body of two piece design complete with
an integral notch plate for handlever use, and
this body also enables the use of a one-piece
discstem.
The one piece disc stem provides the minimum
possible flow restriction when the valve is
fullyopen.
Potentially dangerous practices:
• disregarding instructions
• improper use of product
• use of insufficiently qualified personnel
Application pressure/temperature must not be
higher than the pressure/temperature limits
shown on the datasheet.
Application medium must be in accordance
with the Keystone Chemical Compatibility list.
2 STORAGE
When valves are to be stored for some time
(2months or more) before being fitted, storage
should be in the original delivery crates or
cases.
Storage conditions
The valves should be stored off the ground in a
clean, dry indoor area.
Protect the valve from temperature and
humidity extremes, and exposure to excessive
dust, moisture, vibration, deformations,
sunlight and ozone.
Recommendations
1. Temperature: storage temperature below
25°C, above 0°C preferable below 15°C.
2. Humidity: storage conditions should be such
that condensation does not occur, store in
a dry environment. Maximal 50% relative
humidity.
3. Light: valve rubbers should be protected
from light, in particular direct sunlight or
strong artificial light with high ultra violet.
4. Ozone: storage rooms should not
contain any equipment generating ozone.
E.g.lamps, electric motors.
IMPORTANT
Before valves are being installed or used the
following actions are recommended.
1. Valves/parts have to be inspected and
thoroughly cleaned if required.
2. Rubber parts need to be greased with silicone
grease if not present anymore.
3. All surfaces in contact with seats have to be
thoroughly cleaned and greased with silicone
grease if stored for more than 5 months.
© 2017 Emerson. All Rights Reserved.Emerson.com/FinalControl VCIOM-00760-EN 17/12
Before installation these instructions must be fully read and understood

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QYY
Installation in an existing system
(seediagrams)
1. Check that the gap between the flanges
can accommodate the valve face to face
dimension.
2. Spread the flanges using suitable tooling
such as flange spreaders to enable ease of
insertion of the valve between the flanges.
WARNING
Do not use the valve as a lever for this purpose.
3. Open the valve until the disc is free of the
seat but still contained within the face to
face of the valve.
4. Loosely insert two or more flange bolts
through the holes in the lower part of the
flanges to help support the valve.
5. Carefully slide the valve between the
flanges, center the valve body with the
pipeline axis, and insert the remaining
flange bolts.
6. Open the valve fully, checking that the disc
edge does not interfere with the pipeline
bore.
7. Remove any flange spreaders that have
been used and at the same time tighten
the flange bolts ‘hand tight’. Ensure that
the valve remains centered to the pipeline
axis by slowly closing the valve (clockwise
rotation of the disc stem) to check that
adequate clearance has been maintained
between the disc edge and the pipeline bore.
8. Re-open the valve (counter clockwise
rotation of the disc stem) and tighten all
flange bolts to the recommended torque
of the bolt supplier using the diagonal
sequence method.
9. Operate the valve to the desired position.
4 INSTALLATION
Installation in pipeline
Figure 990/991 valves are bi-directional and
there is no need to identify upstream and down
stream orientation.
Figure 990/991 valves can be installed in
vertical or horizontal pipelines and any
intermediate orientation.
There is no restriction on the valve stem
position (vertical, horizontal or oblique),
although for slurry service and media, which
have a tendency to deposit sediment, the
recommended installation position is with
the stem horizontal and the lower disc edge
opening downstream.
3 FLANGE AND PIPELINE COMPATIBILITY
Figure 990/991 valves are suitable for use with
flanges according to PN 10, PN 16, ANSI 150
and BS table E. Figure 990/991 is a wafer type
valve and is intended to be clamped between
flanges attached to the pipeline.
The minimum allowable pipeline bore at the
flanges shall be the ‘Q’ dimension shown in the
valve data sheet plus adequate allowance to
ensure the disc edge does not interfere with the
pipeline bore.
D max.: The optimum inside diameter (ID) is
equal to the inside diameter of flange
standard EN 1092-1, table 8, type 11.
For larger than D max inside diameters
or other flange types please contact
your local Emerson Sales organization,
as larger inside diameters might result
in reduced valve functionality.
For flanges with a raised face the diameter of
the raised face shall be a minimum of 10 mm
larger than the ‘YY’ dimension shown in the
data sheet.
Do not use flange gaskets, these lead to valve
damage!
D max./min.
Flow
Open
KEYSTONE FIGURE 990/991 BUTTERFLY VALVES
InstallatIon, operatIon and maIntenance InstructIons

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EXISTING SYSTEM NEW SYSTEM
1. Spread the flanges with the adequate tooling.
Insert some flange bolts to bear the valve.
1. Center a flange-valve-flange assembly between
the pipes.
2. Open the valve and remove the flange spreads. 2. Tack weld the flanges to the pipes.
3. Close the valve clockwise, return to open position
and cross-tighten all bolting.
3. Remove the valve and finish weld. Install the valve
according to the procedure in the left column.
Installation in a new system (see diagrams)
It is common practice to use the valve to help in alignment of the flanges
prior to welding the flanges into the pipeline. In such cases, the following
instruction applies:
1. Open the valve until the disc is free of the seat but still contained
within the face to face of the valve.
2. Align both mating flanges with the valve center line and secure in
position using the flange bolts.
3. Position the flange/valve/flange assembly in the pipeline.
4. Tack weld the flanges to the pipeline.
5. Remove the flange bolts and the valve.
6. Finish weld the flanges to the pipeline and allow to cool fully.
7. Follow the procedure for installation in an existing system.
KEYSTONE FIGURE 990/991 BUTTERFLY VALVES
InstallatIon, operatIon and maIntenance InstructIons
WARNING
Do not finish weld the flanges to the pipeline with the valve still assembled
to the flanges as this will result in serious damage to thevalveseat.

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25 M6 6.0
40 M6 6.0
50 M8 8.0
65 M8 8.0
80 M8 8.0
100 M10 14.5
125 M10 14.5
150 M12 20.0
200 M12 20.0
250 M16 50.0
300 M16 50.0
5 MAINTENANCE
Routine maintenance is not normally necessary
for Figure 990/991 valves. If, however, the valve
does need to be serviced or repaired for any
reason, the following applies.
Removing valve from pipeline
1. Turn the disc to the almost closed position
(approximately 5° before closed). The
parallel flats or the keyway on the stem
arein line with the disc.
2. Loosen all the flange bolts and remove
enough bolts to allow the valve to be
withdrawn from between the flanges.
3. Spread the flanges using appropriate
tooling and carefully remove the valve
frombetween the flanges.
Valve disassembly
1. Turn the disc to the open position.
2. Remove the screws that fix the two body
halves together.
3. Remove the lower body half by inserting
flat ended levers into the opposite splits
between the body halves and force the body
halves apart. Broad bladed flat head screw
drivers are acceptable tools.
4. Remove the disc stem and seat from the top
body half.
5. Remove the bushing and packing from the
neck bore of the top body half.
6. Deform the seat into a long oval, which is
sufficient to release the bottom (short) end
of the stem from the seat hole.
7. Pull the long end of the stem from the other
seat hole using a twisting action if required.
Valve assembly
1. Clean all components and replace any
damaged components.
2. If the seat is TFE lined, it is necessary to
immerse the seat in near boiling water
(90°C to 98°C) for 30 minutes to give
enoughflexibility for assembly.
RECOMMENDED TIGHTENING TORQUES FOR BODY SCREWS
Valve size (DN) Bolt size Tightening torque (Nm)
KEYSTONE FIGURE 990/991 BUTTERFLY VALVES
InstallatIon, operatIon and maIntenance InstructIons
3. Insert the long end of the stem into one of
the transverse seat holes using a twisting
action. If possible, a smear of silicone
grease on the stem will ease this operation.
4. Deform the seat into a long oval sufficient
to clear the short end of the stem and push
the short end of the stem into the remaining
transverse seat hole.
WARNING
Protective gloves should be worn for this
procedure especially if a TFE lined seat is being
fitted as this will be very hot after immersion in
near boiling water.
5. Fit the long end of the disc stem into the top
half of the body and ensure that the seat is
properly located in the dovetail recess of the
body half.
6. Insert the bushing and packing into the top
end of the body neck bore.
7. Fit the bottom body half over the short end
of the disc stem and to the top body half,
ensuring that the seat is properly located in
the dovetail recess of the body half, and that
the small rectangular bosses on each body
half are aligned to each other.
8. Secure the top and bottom body halves
together using the two hexagon socket cap
screws, which should be tightened to the
recommended torque.
Abrasive fluids
Where abrasive fluids are used in the valve,
the condition of the seat and disc should be
carefully checked at each maintenance period.
Generally, tears or scores in the seat of more
than 1 mm deep would require the seat to be
replaced. Scores at the sealing edge of the disc
of more than 0.5 mm deep would require the
disc/stem to be replaced.

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45°
6 SAFETY RELATED INFORMATION
1. If in any doubt regarding any aspect of
figure990/991 valves, contact your local
Emerson sales office for guidance.
2. Only use properly qualified personnel for
installation and maintenance.
3. Ensure that the pipeline is fully drained or
vented before removing the valve from the
pipeline.
4. Use appropriate protective equipment /
clothing, such as goggles, safety shoes,
industrial gloves.
5. When used on line fluids with a temperature
of 80°C or more, the valve body can become
very hot and should not be handled without
appropriate protection.
6. The body material is grey cast iron, which is
a known brittle material and heavy impacts
such as blows with a steel headed hammer
should be avoided. The piping design should
preclude the occurrence of water hammer
at the valve.
7. Where water hammer is a potential
problem, ensure that the opening and
closing speed will not cause this to occur.
8. These valves are not to be used for end of
line service.
9. This product is not intended for use in areas
where external fire is a potential hazard.
10. The piping design must take into account
the following factors and any other factors
which are not listed here, but known to
be relevant to the safe operation of the
installation.
Parts list
1Bushing
2Shaft seal
3Upper body
4Seat
5Disc stem
6Lower body
7Body screws
7 OPERATION
1. F990/991 valves are opened and closed by
turning the top of the stem through 90°
using a lever or a gearbox or a quarter turn
actuator.
2. Conventionally, the stem is turned 90°
counter clockwise to open the valve and 90°
clockwise to close the valve.
3. The valve position is indicated by the
orientation of the flats or key on the top of
the valve stem.
If the flats or the centerline of the key are
transverse to the pipeline axis, then the
valve is closed. If the flats or the centerline
of the key are in line with the pipeline axis,
then the valve is open.
4. When actuators or gearbox are used
to operated the valve, the operating
instructions of the actuator or gearbox
mustbe complied with.
KEYSTONE FIGURE 990/991 BUTTERFLY VALVES
InstallatIon, operatIon and maIntenance InstructIons
10.1. Valve weights which are shown in
thedata sheets.
10.2. Formation of condensate in gas
pipelines.
10.3. Elimination of turbulence and vortex
potential at the valve.
10.4. Pipeline vibrations.
11. The valve design has not taken into account
earthquake loading or traffic vibration.

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