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4
MAINTENANCE
4.1
General
Although the valve does not require any regular mainte-
nance, you should check the tightness of the gland
packing from time to time and, if necessary, take a few
simple maintenance measures. This chapter outlines
the measures the valve user can take.
The numbers in brackets referto the exploded view and
the lists of parts in Section 10.
4.2
Maintenance of a mounted valve
4.2.1
Gland packing
Replace the gland packing (69) if the tightening of the
nuts does not stop leakage.
Ensure that the valve is unpressurized and remove the
actuator. Then remove the existing gland packing using
a tool that does not damage the tightening surfaces.
Install the new gland packing as instructed in Sections
4.7.4 and 4.7.5.
4.2.2
Body and bonnet joint
Should the body joint leak tighten the nuts as indicated
by the torques in Section 4.7.3.
4.2.3
Turning the ball
If the ball’s tightening surface is so badly damaged that
the valve leaks in closed position, turn the ball 180
degrees. Note the effect of the measure on the orienta-
tion of the actuator. Should the leaking continue, send
the ball to the manufacturer for repairs.
Do not turn a ball with a Q attenuator. For further
instructions, contact the manufacturer.
4.3
Removing the actuator from the
valve
It is usually easiest to remove the actuator and its sup-
port equipment before removing the valve from the
pipeline. If the package is small or not easily accessi-
ble, it is better to remove the entire package at one go.
❑
Close and detach the actuator pressure supply
and remove the control cables and pipes from
their couplers.
❑
Loosen the bracket screws.
❑
Remove the actuator from the valve with an
extractorthat can be ordered from the manufac-
turer (See Chapter ’Tools’). See Figure 7.
❑
Remove the bracket and any coupling.
4.4
Removing the valve from the
pipeline
❑
Make sure that the pipeline is empty and unpres-
surized and that there is no medium flowing into
the pipeline while the valve is not in its normal
position.
❑
Carefully attach the ropes, loosen the pipe flange
screws and lift the valve using the ropes. Make
sure that you lift the valve correctly. See also Fig-
ure 5.
CAUTION:
Familiarize yourself with the safety precautions in Sec-
tion 1.7 before any maintenance operations!
CAUTION:
The valve and valve package are heavy. Remem-
ber this when handling them.
NOTE:
Always use original spare parts to ensure proper
valve functioning.
NOTE:
A valve sent to the manufacturer for servicing should not
be dismantled. Clean the valve carefully from inside and
outside and, to ensure safety, inform the manufacturer of
the type of medium involved.
CAUTION:
The valve package is heavy. Remember this when
handling it.
NOTE:
To ensure proper reassembly, observe the position of the
actuator and the positioner/limit switch with respect to the
valve before removing the actuator.
Fig. 7
Removing the actuator with the extractor
CAUTION:
Do not remove or dismantle a pressurized valve!
