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Safety valves are used
to maintain pressure under a fixed rate and consequently
to protect vessels and pressure equipments from uncontrolled
overpressures. Direct load which defines discharge pressure
is obtained with helicoidal springs. This system gives
the advantage to have an high discharge capacity with
a reduced pressure gap from the start of the valve opening
to its complete closure.

Our safety valves, with
regard to type and employed materials can normally work
at the following conditions:
- / 1 / - set-pressure range
from 0,4 to 100 bars for homologated valves, from 2
to 400 bars for ordinary valves;
- / 2 / -working temperature
-270°C ÷ +538°C;
- / 3 / -overpressure <=
10%;
- / 4 / -blowdown <= 10%
( <= 15% for "R" type).
Our safety valves are
marked on their bodies with the following data:
- UNIVERSAL stamp;

- Valve type; Serial number;
- Set pressure; Year of
construction;
- Working pressure;
- CE stamp;
- Notified Body identification
number;
We produce safety valves
with free discharge in the air or with conveyed discharge
for dangerous or toxic fluids. In the last case, valves
can have different lifting device types for emergency
actions or periodic checks.

We make all safety valve
components directly, with the exception of the smallest
ones of brass. Therefore, We can assure:
- high and constant quality;
- fast deliveries due to
an easy work planning;
- fast production for all
types of safety valves and special connections.
Our valves are designed
and manufactured in accordance with the following standards/normatives:
-
- I.S.P.E.S.L. rules,
"E" Collection, E1D2 Dossier;
-
- 97/23/CE Directive (PED);
-
- ATEX Directive;
-
- EN ISO 4126-1 European
Normative
Construction and employed
materials depend on pressure, temperature, corrosivity
and on all other characteristics of the fluid in touch.
Safety valves, according to the requested characteristics
and quality, can be made out of bars, casting or hot
moulding.
All employed materials
have their own original test certificates that can be
supplied when customers require them. After machining,
to increase ageing strength and corrosion proofness,
many other treatments can be made on each valve component,
i.e. pickling, sandblasting, buffing, galvanizing, nickel
plating, chromium-plating, anodizing, etc..
Examination of valve components:
- BODY: it is made
out with particular attention respecting dimensions
and thickness in conformity with the declared rating.
We can supply all possible connections respecting the
following conditions:
In the upper side of valve
body (bonnet) there is an hole to discharge the back
pressure that develops during valve opening. Conveyed
valves, used for dangerous and toxic fluids, have this
hole between bonnet and discharge duct in order to avoid
any loss of fluid in the air.
- ORIFICE AND SEAT:
valve seats are flat. With regard to safety valves with
metal to metal seats a perfect tightness is assured
by a careful machining. As concerns soft seats, We have
various gaskets of different materials according to
the valve specific use. In order to avoid a gasket overload,
safety valves are usually manufactured to let the disc
lay on the bottom of the valve seat when there is no
fluid pressure. In this way valve gasket maintains good
strength and elasticity for a long time and avoids sticking
of the disc on the seat.
- DISC: the valve
disc has been designed to obtain the maximum discharge
capacity. The machining tolerances let it work perfectly
in all conditions.
- PUSH-ROD AND SPINDLE:
they are used to maintain a correct spring alignment.
- ADJUSTING SCREW:
it works also as a guide for the valve spindle. After
the valve setting, the adjusting screw is locked by
a pin or a rivet.
- LOCKING CAP:
with regard to safety valves with free discharge in
the air, the locking cap has been designed to protect
all inner components against tamperings that can be
done only by heavy actions on the valve structure. The
locking cap is also used to limit the disc lift by stopping
of the spindle lift.
- COVER FOR EXTERNAL
PROTECTION: it is made of aluminium and it is used
as a further valve protection against atmospheric agents
and dust. It is fixed on the valve locking cap with
a blind nut that, after having been blocked and crosswise
drilled, is used for the passage of the sealing wire.
- LIFTING DEVICES:
there are different types of valve lifting-devices.
The first one is made by a ring nut, the second one
by a lever and the third one by a pneumatic actuator.
When lifting devices are operated, they make stem lift
up and spring compress, so that the valve disc runs
freely. These devices don’t block or get the valve disc
out of the seat when the lifting power fails.
- SPRING:: we generally
use helicoidal stainless steel springs, according to
EN 10270 European Normative. The upper spring seat is
located on the lower side of the adjusting screw, whereas
the lower seat is on the push-rod of the valve spindle.
In this way there are excellent conditions of alignment
and axial load during work.

UNI EN ISO 9001:2008 (ISO
9001:2008) certificate

ATEX Certificate

CE PED.06.0013.05/1907
approval certificate
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