Setting The Set Pressure - Leser 4401 Instrucciones De Servicio

Operating Instructions
the drainage opening, then the bellows is
faulty. Faulty bellows must be replaced im-
mediately.
Bellows should be checked when disas-
sembling the safety valve and always re-
placed if there is any damage.
Bellows have a limited number of load
reversals. The bellows must be replaced
when that number of load reversals has
been reached.
Gaskets and gasket points must be
checked regularly. If the seal tightness re-
quirements are no longer fulfilled, then the
gaskets must be replaced. Spare assem-
blies can be ordered from LESER.
If the set pressure is to be changed, then
the spring table must be used to check
whether the spring may be used. The cor-
rect spring for the designated set pressure
must be used. After the set pressure has
been changed, the configuration of the en-
tire safety valve must be checked.
The seal must be removed to adjust the set
pressure and to replace the spring. This
voids the guarantee. Changes should be
made in the factory, by an authorised work-
shop, or by a notified body.
The residual test medium remains inside
after adjusting the pilot-operated safety
valve. The user must determine whether
the product is compatible with the fluid, and
initiate additional flushing measures, if re-
quired.

9.2 Setting the Set Pressure

Different steps are required for the disas-
sembly, depending on the system and type
of safety valve. Only the essential steps
are summarised and given in the following
handling instructions. The handling instruc-
tions are only intended to provide a rough
orientation and only apply to basic safety
valves without special options. The de-
tails must be taken from the type-specific
guides.
WARNING
Leaking medium
Danger to persons and the environment.
• Take safety measures in accordance
with the medium.
• Capture the medium
from the pipelines.
• Do not allow unauthorised
persons in the danger zone.
• Wear suitable protective equipment.
CAUTION
Spindle is not protected against
twisting
Damage to the sealing surfaces.
• Secure the spindle against twisting.
Prerequisites
• Ensure the system is not under pressure.
• There must not be any media in the bon-
net of the safety valves.
EN
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