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1 XH 70 en
3.2.1 Valve insulation
If necessary, the valve may be insulated. Insulation must not
continue above the upper level of the valve body, see
Figure 9.
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 cylinder.
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 nor-
mally be associated with large actuators, extended shafts, or
where severe vibration is present. Please contact Metso
Automation 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 refers 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
maintenance 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
Changing the gland packing while the
valve is in the pipeline
In graphite gland packings, tightness is ensured by contact
between the gland follower and the packing rings.
The gland packing (69) must be changed if leakage occurs
even after the hex nuts (18) have been tightened.
Make sure that the valve is not pressurized.
Detach the actuator and bracket according to the
instructions in Section 4.4.
Remove the key (10).
Fig. 9
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.
I n s u l a t i o n
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 manufac-
turer 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!
Summary of Contents for Neles XH Series
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