Metso M07, Инструкция по установке, обслуживанию и эксплуатации

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4.3 Repair of a jammed or stuck valve
while it is in the pipeline
Jamming may be due to the ball (3) and seats (7) becoming
clogged with flow medium. They may be cleaned by turning the
ball to the partly open position and flushing the pipeline. If this
does not help, follow the instructions in the following sections.
4.4 Detaching the actuator
CAUTION:
When handling the valve or the valve package as a
whole, bear in mind the weight of the valve or the
entire package!
NOTE:
Before dismantling, carefully observe the position of the valve
with respect to the actuator and positioner/limit switch so as
to make sure that the package can be properly re-assembled.
It is generally most convenient to detach the actuator before
removing the valve from the pipeline. If the valve is small or if it
is difficult to access, it may be more practical to remove the entire
package at the same time.
Note that the seats can be replaced without detaching the
actuator.
Close and detach the actuator pressure supply pipeline
and remove control cables.
Unscrew the bracket screws.
Detach the actuator. The actuator can be removed by
hand or with a special tool made for this purpose. The
tool can be ordered from the manufacturer (see section
"Tools").
Remove the bracket and coupling.
4.5 Removing the valve from the pipeline
CAUTION:
Do not dismantle the valve or remove it from the
pipeline while the valve is pressurized!
Make sure that the valve is not pressurized and that the
pipeline is empty. Make sure that the medium cannot flow
into the section where servicing is to take place.
Support the valve carefully with a hoist. Place ropes
carefully and unscrew the pipe flange bolts. See that the
ropes are positioned correctly, see Fig. 10. Lift valve
down.
4.6 Dismantling the valve
4.6.1 Sizes DN 25-40, 65
Place the valve in a standing position on the pipe flange
end so that the body cap points upwards. Use a level
surface that will not scratch the pipe flanges.
Unfasten the gland follower (9) nuts. Remove the gland
follower and the packing rings (69).
Unfasten the bolts of the stem retainer (8). Remove the
gland, the stem retainer seal (66), the stem (5) and the
thrust bearings (70, 71).
Unscrew the insert (2) using a suitable tool. See section 8
"Tools". Remove the ball (3) and seats.
Remove the locked seat (7) using a special tool that can
be ordered from the manufacturer, see Fig. 16.
Fig. 15. Removing the actuator with an extractor
Fig. 16. Removing the locked seat
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