excellence of Italian engineering
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Field adjustab
RELIEF VALVES
excellence of Italian engineering
OUR MISSION:
We started in 1960 as instrumentation manufacturers and we have
increasingly specialized in high quality valves.
Italian know-how and production, combined with qualified European
suppliers, make Sami the excellence of Italian engineering.
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RELIEF VALVES
WHAT:
Relief valves are devices which protect the system from overpressure by draining the fluid
when the pressure exceeds a set value.
HOW:
The valve OPENS when the pressure exceeds a set
value and CLOSES when it falls below.
Normal state:
Force of pressure on stem ‹ force of pressure of
spring = CLOSED
Overpressure:
Force of pressure of system › force of pressure of
spring = stem lifts and valve OPENS
The set pressure is easily adjusted by the customer
by turning a screw on the top of the valve
Please note: Sami’s pressure relief valves are
unidirectional, are not to be plugged or plumbed
in series and must have an independent exhaust to
atmosphere.
WHERE:
WHERE NOT:
Relief valves are used:
NOT to be used:
•in systems or containers where it’s important
•below 1.000 psi (69 bar);
to protect the equipment from overpressure;
•in systems where the relief valves must have
• with high or low temperature fluids;
a capacity rating at a given pressure rise:
our product is designed to open gradually
when the pressure increases;
• to control overpressure caused by heat
expansion of a fluid;
• where the low drain rate in high pressure
systems isn’t a critical factor;
• where a “bubble tight” seal is requested.
•in systems with ASME Boiler and Pressure
Vessel Code or 97/23/EC standards: our
relief valves do not comply with ASME or
PED standards;
•where back pressure during drain may
occur;
•with corrosive fluids or liquid nitrogen,
which, in the expansion phase, could
generate cryogenic temperature gas,
4 damaging the valve.
RELIEF VALVES
MAIN FEATURES:
Field adjustable set pressure
can be set in factory and readjusted in the plant, if needed
Long life
thanks to soft seat and strong coil springs
High accuracy
designed to control minor overpressure
Fast response
thanks to a simple structure, with few mechanical components
Easy to use
all you need is a screw to adjust the set pressure
Easy maintenance
with few spare parts and easy-to-reach seat
Bubble tight
thanks to soft seat based on a tilt angle
CODING SYSTEM:
R10
SERIES
R10 RELIEF VALVE 10.000 psi
R20 RELIEF VALVE 20.000 psi
TYPE
M01 SCREW ADJUSTABLE RELIEF VALVE - SOFT SEAL - ORIFICE 0,07”
SIZE
T01 1/4” C&T T11 1/4” NPT
T02 3/8" C&T T12 3/8” NPT
T03 9/16” C&T
MATERIALS
A Aisi 316
(standard)
Other materials available upon request.
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M01
T01
A
RELIEF VALVES
TECHNICAL FEATURES:
Inlet
NPT-F: 1/4” – 3/8”; C&T: 1/4” - 3/8” - 9/16” female
Outlet
1/4” NPT-F
Design and set pressure
From 1.000 to 10.000 PSI (69-689 bar) for model
R10M01*** From 10.000 to 20.000 PSI (689-1378 bar) for
model R20M01***
Cv/Kv
0.12 / 0.10
Full rate
Overpressure: 10% higher than set pressure
(approx. 5mm opening)
Working temperature
Standard -46°C /+150°C (-50°F/ +302°F)
Body material
AISI 316
Packing material
Nylon or PTFE
O-rings material
FKM
Orifice
1.8 mm (0.07”)
Standard testing
Shell test at 1.5 x rating - medium: water
Seat test at set pressure - medium: water
Certificate included
(free of charge)
EN 10204 3.1
Set pressure adjustment
100% in plant or in factory
Medium to be used
Water or gas
SET PRESSURE:
Spring compression
R10M01T11
R20M01T01
%
h-mm (inch)
Psi (bar)
Psi (bar)
5
2,6 (0,10”)
1.937 (133)
3.970 (274)
15
7,6 (0,30“)
5.812 (400)
11.908 (821)
25
12,7 (0,50“)
9.687 (668)
19.846 (1368)
The upstream pressure at which the first indication
of flow occurs determines the set pressure.
The table above shows the set pressure which can be
reached by compressing the internal
spring at a given height “h”.
The maximum set pressure can be reached at
approximately 25% of the total spring length.
The values are to be regarded as an indication and
refer to working conditions at room temperature
(-29°C + 38°C / -20°F + 100°F).
A tolerance value of ±10% must be considered.
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H
RELIEF VALVES
TABLE OF MATERIALS:
PART
DESCRIPTION
MATERIAL
1
Upper thrust washer
ASTM A276/A479 316
2
Thrust bushing
PTFE
3
O-ring 2032
FKM Endura V91A
4
Bottom thrust washer
ASTM A276/A479 316
5
Bottom spring
AISI 302
6
Shutter
AISI A564 T630 H900
7
Bushing
ASTM A276/A479 316
8
Seat
Nylon or PTFE
9
Socket set screw 1/2” UNC x 2”
ASTM A193 GR. B8M
10
Hexagon low nut 1/2 UNC-2H
ASTM A194 GR. 8M
11
Upper fitting
ASTM A276/A479 316
12
Upper spring bushing
ASTM A276/A479 316
13
Springs
Carbonsteel
14
Lower spring bushing
ASTM A276/A479 316
15
Valve body
ASTM A276/A479 316
16
O-ring 2050
FKM Endura V91A
17
Closure fitting 1/4” NPT-F
ASTM A276/A479 316
Parts marked in BOLD are the ones included in the repair kit.
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10
11
12
13
14
15
16*
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REPAIR KIT CODES:
Valve code
Repair kit code
R10M01**
KR10M01**
R20M01**
KR20M01**
1*
3*
5
6
7
8*
7
2*
4*
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OVER
SAMI INSTRUMENTS® S.r.l.
Via Botte, 8 - Reschigliano di Campodarsego
35011 - Padova (Italy) Tel. +39.049.9201939
[email protected]
www.samivalves.com