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3.3
Actuator
The valve open/closed position is indicated as follows:
by an indicator on the actuator
or
by a groove at the end of the ball shaft (parallel to
the ball flow opening).
If there is any uncertainty about the indicator, check the ball
position by the groove.
The actuator should be installed in a manner that allows
plenty of room for its removal.
The upright position is recommended for the actuator cyl-
inder.
The actuator must not touch the pipeline, because pipeline
vibration may interfere with its operation.
In certain cases it may be considered advantageous to pro-
vide additional support to the actuator. These cases will
normally be associated with large actuators, extended
shafts, or where severe vibration is present. Please contact
Metso’s Automation business for advice.
3.4
Commissioning
Ensure that there is no dirt or foreign objects left inside the
valve or pipeline. Flush the pipeline carefully. Make sure
that the valve is entirely open when flushing.
Ensure that all nuts, pipings, and cables are properly fas-
tened.
Check that the actuator, positioner, and switch are correctly
adjusted. Actuator adjustment is explained in Section 6. To
adjust the accompanying device refer to the separate con-
trol equipment instruction manuals.
4
MAINTENANCE
4.1
Maintenance general
Although Metso’s Neles valves are designed to work under
severe conditions, proper preventative maintenance can
significantly help to prevent unplanned downtime and in
real terms reduce the total cost of ownership. Metso recom-
mends inspecting the valves at least every five (5) years. The
inspection and maintenance interval depends on the actual
application and process condition. The inspection and main-
tenance intervals can be specified together with your local
Metso experts. During this periodic inspection the parts
detailed in the Spare Part Set should be replaced. Time in
storage should be included in the inspection interval.
Maintenance can be performed as presented below. For
maintenance assistance, please contact your local Metso
office. The part numbers in the text refer to the exploded
view and to the parts list in Section 10, unless otherwise
stated.
4.2
Replacing the packing without
removing the valve from the pipeline
The V-ring gland packing requires no regular tightening.
The gland packing tightness is provided by the pipeline
pressure together with gland pressure against the packing
rings. In graphite gland packings, tightness is ensured by
contact between the gland follower and the packing rings.
Fig. 15
Insulation of the valve
NOTE:
When installing the actuator on the valve, make sure that
the valve package functions properly. Detailed informa-
tion on actuator installation is given in Section 6 or in the
separate actuator instructions.
Insulation limit
CAUTION:
Observe the safety precautions mentioned in Section
1.8 before maintenance!
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:
When sending goods to the manufacturer for repair, do
not disassemble them. Clean the valve carefully and flush
the valve internals. For safety reasons, inform the manu-
facturer of the type of medium used in the valve (include
material safety datasheets (MSDS)).
NOTE:
In order to ensure safe and effective operation, always use
original spare parts to make sure that the valve functions
as intended.
NOTE:
For safety reasons, replace pressure retaining bolting if the
threads are damaged, have been heated, stretched or cor-
roded.
CAUTION:
Do not dismantle the valve or remove it from the pipe-
line while the valve is pressurized!
CAUTION:
For safety reasons the retaining plates (42) MUST
always be installed as shown in Section 4.2.
Summary of Contents for XB/XC Series
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