6
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 Fig-
ure 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 cylin-
der.
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
SERVICING
4.1
General
Although XH-series ball valves require no regular maintenance, it
is recommended that the gland packing be checked regularly for
tightness. If for some reason the valve should require mainte-
nance, then a few simple service measures should normally suf-
fice. This section outlines the service operations that can be carried
out by the end user.
The numbers in parentheses refer to the parts list and the
exploded view of the valve in Section 10, if not 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).
Remove the nuts (18), the disc spring sets (150) the
gland (9A), retainer ring (42) and sleeve (9B).
Remove old packing rings (69). Do not damage the
surfaces of the packing ring counterbore and shaft.
Clean the packing ring counterbore.
Place the new packing rings (69) over the shaft (5).
The gland follower may be used for pushing the rings
into the counterbore. Do not damage packing rings in
the shaft keyway.
Pre-compress the packing rings first either by tight-
ening the gland nuts (with or without disc springs)
to the torque Tt or by tightening the gland with disc
springs to the height H
2
. See Fig. 10 and the value
from Table 1.
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.
Insulation limit
CAUTION:
Observe the safety precautions mentioned in Section
1.8 before servicing!
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:
Always use original spare parts to make sure that the valve
functions as intended.
NOTE:
If you choose to send the valve to the manufacturer for
servicing, do not dismantle it. Instead, clean the valve care-
fully of all medium and inform the manufacturer of any
dangerous medium involved.
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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