7 operation, 1 initial commissioning, 2 improper operation and their consequences – Richter KNAP-S/F Series Ball Valves (ASME) User Manual

Page 11: 3 shutdown, 8 malfunctions, Initial commissioning, Shutdown, 7operation, 8malfunctions, Series kna/f, knap/f, kna-d/f, knap-d/f

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Series KNA/F, KNAP/F, KNA-D/F, KNAP-D/F,

Page 11

KNA-S, KNAP-S,

ASME

9520-080-en_USA

Revision 10

TM 8361

Edition 10/2011

7

Operation

7.1 Initial commissioning

Normally, the ball valves have been tested for leaks
with air or water. Prior to initial operation check body
bolting. For torques see Section 1.2.

Unless otherwise agreed, there could be
residual amounts of water in the flow section
of the ball valve; this could result in a
possible reaction with the medium.

To prevent leaks, all connection screws must be
checked and retightened if needed after the initial
loading of the valve with operating pressure and
operating temperature.
For torques see Section 1.2.

7.2 Improper operation and their

consequences

Under no circumstances must the operating
parameters specified on the identification plate be
exceeded.
Failure to operate the valves within the
operating parameters voids the warranty!

The ball valve is an on/off valve and shall not be
operated in an intermediate position.
Damage to the seat rings, the ball/stem unit or
Al

2

O

3-

ball/stem could occur.

Crystallisation may result in damage to the seat
rings or ball/stem unit or Al

2

O

3-

ball/stem. This can

be prevented by heating. In extreme cases this
may cause blocking.

If the ball blocks, do not apply force as the
ball/stem unit or Al

2

O

3-

ball/stem may break if the

max. adm. torque is exceeded.
Operation with solids leads to increased wear.
Operating during cavitation leads to increased
wear.
Non-observance of the pressure-temperature
diagram can lead to damage.
Do not subject the lever to heavy loads; the lever
or ball valve may be damaged.
Do not use a lever extension as otherwise there is
a risk of damage.

7.3 Shutdown

The local regulations are to be observed when
dismantling the valve.
Prior to undoing the flange connection ensure,
that the plant is depressurised and emtied.

Prior to starting any repair work, the valve is
to be thoroughly cleaned. Even if the valve
has been properly emtied and rinsed,

residual medium may still be found in the valve.
After dismantling, immediately protect the valve
flanges against mechanical damage with flange caps.
See also Chapter 6.1.

Ensure that a remotely actuated actuator
cannot be accidentally switched on.

8

Malfunctions

Flange connection ball valve/pipe is leaking
Retighten the flange screws to a tightening torque
according to Section 1.2. If this does not remedy
the leak, the recommended torques may be ex-
ceeded by 10%.
If this also fails to stop the leak, dismantle and
inspect the ball valve.
Flange connection main body/body end piece is
leaking
Retighten body screws. See paragraph "Flange
connection valve/pipe is leaking".
Packing is leaking
Retighten packing nuts according to the details in
Section 1.2.
Ball valve does not operate
Is the actuator being supplied with power?
Is any directional control valve connected correct-
ly?
Is there any foreign matter in the valve?

The ball no longer closes completely
Is the stem deformed?
Is the coupling worn?
With a worm gear or actuator, check whether the
end stops can be re-adjusted. The operating
manuals of the gear and actuator manufacturers
contain accurate instructions.


Never apply force to the lever or use an
extension.

1. Try to get the ball valve working again by

moving the lever to and from.

2. Remove the lever stop and try to switch against

the normal direction of rotation.

3. If actuation is not possible with the max. admis-

sible breakaway torque as per Section 1.3,
dismantle ball valve and inspect individual

components.

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