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replace it with new one. If it is possible -
apply valve with soft seal on the valve
disc, which has a lower sensitivity to grit in
the seat. Follow manufacturer’s
instructions.
Corrosion of elements directly in
contact with the medium, which is the
result of improper valve selection in
respect of material
Replace the valve with the construction
appropriate to the medium according to
resistance of used materials or apply
safety valve system with a bursting disc
The deformation caused by stresses of
the installation. Valve bodies can get
deformed due to excessive load
transferred from the pipes, causing,
among others, leaking.
Diagnose and eliminate the causes of
stress. If the deformations of valve body
are permanent- replace the safety valve
with a new one.
Other causes of leaks on the seat.
Depending on the reason diagnosed -
according to the indications and decision
of the manufacturer - replace the
defective parts or replace the safety valve
with a new one.
Safety valve opens at a pressure
lower than at adjusted set
pressure
With the cold setting of a valve,
appropriate temperature adjustment
was not included. (in case of valves
used for media of 100
o
C and higher)
Revise opening pressure, observing the
guidelines and recommendations of the
manufacturer.
High spring relaxation at the working
conditions (for valves at upper limit for
medium and temperature / pressure)
Consult the manufacturer-replace the
spring, according to the guidelines and
recommendations of the manufacturer. If
possible- apply the valve with open
bonnet construction (better cooling of a
spring) or / and with cooling section.
When such situation reoccurs – replace
the valve with a new one, intended for a
use in higher temperature range.
Slight damage or contamination of the
sealing surface of the seat / disc
Remove the valve, check the sealing
surfaces and, if necessary - make
regeneration according to the
manufacturer's instructions and
recommendations.
The valve is set to the differential
pressure (considering the presence of
superimposed backpressure) when the
backpressure don’t exist
Regulate setting of the valve. If the
required pressure is within the scope of
spring mounted on the valve- set the
safety valve to the required pressure, if it
is outside the scope of spring mounted -
replace the spring with the appropriate
one and set the required pressure.
In each case, act in compliance with
manufacturer’s instructions.
Sudden increases in pressure
(pulsations)
Incorrect positioning of the safety valve
at pressure source
Analyse positioning of the safety valve at
pressure source. Safety valve should be
installed in such a distance from pressure
source that protects it from the pressure
pulsations.
Crack on the valve body
Transport defect
Replace safety valve
defect of the material
Replace safety valve
