Richter NKP Series Butterfly Valves - Manual (Page 14)

Series NKL, NKLP, NKS, NKSP, NK, NKP
Page 14
9520-070-en Revision 04
TM 7113 Edition 05/2008
9.1.1 Safety stuffing box
Insert sealing foil 413 between the upper and lower
halve of the shell 120.
Displace packing rings 402/1 by 90° against each
other
Screw in stuffing box screws 901/3. Only tighten in
the event of a leak.
Safety stuffing box with monitor using warning
connection
Tighten stuffing box bolts 901/3 with torque in ac-
cordance with Section 1.3.
See also Section 9.1.3.
For detailed installation and inspection regulations see
QM No. 0910-08-1005, available from Richter on re-
quest.
9.2 Valve actuation
The valve stem has a pivot to attach a hand lever res-
pectively a coupling.
Hand lever respectively pivot parallel to the axis of the
pipeline:
Valve open
Hand lever respectively pivot at right angles to the
axis of the pipeline:
Valve closed
In the case of a coupling, 2 red marks indicate the
position of the disc on them.
Marks parallel to the axis of the pipeline:
Valve open
Marks at right angles to the axis of the pipeline:
Valve closed
9.2.1 Actuated with lever
The throttling plate 519 permits a fixing of the lever at
15° intervals. It is lockable with a commercially availa-
ble padlock.
9.2.2 Actuated by means of worm gear
In the standard version, the manufacturer normally
provides worm gears with a special pick-up for the
stem pivot.
The bracket and the coupling are thereby not requi-
red.
Commercially available worm gears equipped with a
connection as per ISO 5211 can also be connected.
These require a bracket and a coupling however.
This version is also necessary for butterfly valves with
a safety stuffing box.
Couplings and brackets are available as accessories
in the Richter range of products.
9.2.3 Remotely actuated
Richter butterfly valves can be remotely actuated by
means of pneumatic, hydraulic or electric quarter-turn
actuators equipped with a connection as per ISO
5211.
Couplings and brackets are available as accessories
in the Richter range of products.
9.2.4 Required breakaway torque
The breakaway torque of the actuator must
be at least as high as the breakaway torque
of the butterfly valve, about 20% higher being
better however.
Media of higher viscosity and/or those with solids may
require an increased factor of safety when calculating
the size of the actuator. This is particularly true for
non-Newtonian fluids such as high polymer substan-
ces, suspensions, pastes, lubricants, resins, lacquers
etc.
Admissible factors of safety lie in the range of 20 -
50% of the breakaway torque.
To prevent damage to the valve, particular attention
must be paid to the torque Mdmax in Section 1.8.
9.3 Options
9.3.1 Safety stauffing box
The safety stuffing box acts independently from the
standard shaft gasket and can be re-adjusted by
hand.
Only with the option safety stuffing box: A sealing foil
413 is inserted between the upper section and the
lower section of shell.
If the shaft gasket is damaged, the valve can thus
continue to be operated for a short time.
See drawing Section 10.2.
In order to ensure leak monitoring, Richter recom-
mends the combination of the safety stuffing box with
a warning connection.
If only the safety stuffing box is present, do not tighten
it so that any leak becomes visible.
Otherwise the valve may be destroyed by an unno-
ticed internal leak.
9.3.2 Monitoring connection
The monitoring connection, between the standard
shaft gasket and the safety stuffing box, can be fitted
with attachments for monitoring pressure.
It can indicate leaks or build up a protective nitrogen
layer. See drawing Section 10.2.