Richter KNP-D/F Series Ball Valves (ISO/DIN) - Manual (Page 10)

Series KN/F, KNP/F, KN-D/F, KNP-D/F
Page 10
520-050-en Revision 10
TM 8361 Edition 10/2011
7 Operation
7.1 Initial commissioning
Normally, the valves have been tested for leaks with
air or water. Prior to initial operation check body
bolting. For torques see Chapter 1.2.
Unless otherwise agreed, there could be
residual amounts of water in the flow section
of the valve; this could result in a possible
reaction with the medium.
To prevent leaks, all connection screws should be
retightened after the initial loading of the valve with
operating pressure and operating temperature.
For torques see Chapter 1.2.
7.2 Improper operation and their
consequences
The ball valve is an on/off valve and shall not be
operated in an intermediate position.
Damage to the seat rings or the ball/stem unit or
Al
2
O
3-
ball/stem could occur.
Crystallisation may result in damage to the seat
rings, 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 valve/pipe is leaking
Retighten the flange screws to a tightening torque
according to Chapter 1.2. If this does not remedy
the leak, the recommended torques may be
exceeded by 10%.
If this also fails to stop the leak, dismantle and
inspect the 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
Chapter 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 mov-
ing 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. ad-
missible breakaway torque as per Chapter 1.3,
dismantle ball valve and inspect individual
components.