HG1
10 Annex
10.1 Mounting of operating elements
DANGER
There is an acute danger to life when opening a pressurized valve!
Opening of screw connenctions, limit switches, manual overrides or auxiliary equipment when the
valve is under pressure may result in eruption of the fluid and damage to the valve.
WARNING
Observe safety instructions
Before any work on the valve, the general safety information must be read and observed.
NOTICE
Subsequent construction
In the event of subsequent assembly of operating elements and actuators, which is not carried out
by our personnel, we do not assume any warranty for the correct function of the valve.
NOTICE
Qualified persons
Work on the valve may only be carried out by qualified and authorised persons.
NOTICE
Opening a (pressurized) valve
Since the operator of the valve is responsible for a safety rating, it is important to observe and
comply with all local and company safety regulations. In addition, in order to ensure safe working
on a valve, at least all safety precautions listed below must be taken:
a) Make sure that the pipe section into which the valve has been integrated is depressurised and
drained
b) Let the valve and the flow medium cool down. If dangerous substances have flowed through
the relevant pipe section, it must be additionally rinsed and aerated.
c) Remove attached actuators before removing the valve or secure them against unauthorized
use and accidental operation.
The highest level of tightness can only be achieved when the valve disc is completely closed. In case operating
elements (hand levers, gear operators, actuators, etc.) are mounted, the stop position must be exactly adjusted.
The stop boss does not serve the purpose of a limit stop, but merely as an override safety device which ensures
that the seat ring is not damaged. The highest level of tightness of the valve is achieved ca. 1°-2° before the
stop boss is reached. If the valve is not installed in the pipeline, the exact stop position can be checked as fol-
lows: The distance from the edge of the body to the valve disc must be measured on both sides at a position off-
set 90° to the valve shaft. If the distances are identical, the valve is closed exactly. Care must be taken that the
valve is always moved to the stop position from the opened position. This is the only way to guarantee that any
play from the actuator (e.g. gear) has no influence on the stop position. If the exact stop position has been over-
ridden, the valve must be returned to the opened or partly opened position, then moved back again into the stop
position from this opened position.
It must be ensured that the actuator is centred on the valve shaft. The weight of a mounted actuator must not
place a one-sided load on the valve shaft. For this reason, actuators must be supported if necessary - without
fixation. External loads must not be applied to actuators, this can damage or destroy the valve. If the valve is
mounted in the recommended pressure direction, the opening movement of the valve disc is supported by the
pressure of the medium, this being design-related (double-eccentric design). For this reason, when carrying out
switching operations using a hand lever, the lever is to be held secure when the star knob is being loosened.
After the switching operation has been completed, the position of the hand lever is to be secured by tightening
the star knob.
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Version 0 • Dokument-Nr. 74572811
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