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Propor tional Safet y Relief Valve s

PRV Se r ie s
■ Gas and liquid service

■ Working pressure: 6000 psig (413 bar)

■ Set pressures from 145 to 6000 psig (10.0 to 413 bar)

■ All 316L stainless steel construction

■ 1/4 through 1 in. NPT and ISO/BSP parallel thread end connections

■ Certified to PED 2014/68/EU Category IV

2 PRV Series Proportional Safety Relief Valves

Cover
protects set screw.
Lock wire capability
secures cover to maintain
set pressure adjustment.

Set screw
provides easy external
set pressure adjustment.

Spring
adjusts to provide
desired set pressure.

Poppet
seals bubble-tight against seat
O-ring seal for accurate resealing.
seals around poppet
during relief mode. Seat ring
contains the seat seal
during pressurization.

Seat seal Seat

provides elastomer-to-metal ■ 316L stainless steel
seal for positive shutoff. ■ provides positive shutoff for poppet.

Features Applications
■ All 316L stainless steel wetted metal components PRV series relief valves are proportional safety relief valves
■ Five set spring pressure ranges that open gradually as the pressure increases above the set
pressure.
■ Factory-set, tested, locked, and tagged with the set
pressure • Swagelok® proportional relief valves should never be
■ CE-marked in accordance with the Pressure Equipment used as safety relief devices in steam applications
Directive as a safety valve according to ISO-4126-1 such as ASME Boiler and Pressure Vessel Code
■ Available integral end connections—1/4 and 3/4 in. female Section I, Power Boilers.
NPT and ISO/BSP parallel thread
■ Available end connection adapters—1/2 in. male and female Operation
NPT and ISO/BSP parallel thread, 3/4 in. male NPT, and PRV series relief valves OPEN when system pressure reaches
1 in. male and female NPT and ISO/BSP parallel thread end the set pressure, and CLOSE when system pressure falls
connections below the set pressure.

• For valves not actuated for a period of time, initial

relief pressure may be different than the set
pressure.
 PRV Series Proportional Safety Relief Valves 3

Technical Data
Valve Series PRV2 PRV6
Working Pressure, psig (bar) 6000 (413)
145 to 5290 145 to 6000
Set Pressure, psig (bar)
(10.0 to 365) (10.0 to 413)
Fluorocarbon FKM seal material:
5 to 176 (–15 to 80)
Temperature, °F (°C)
Nitrile seal material:
–4 to 176 (–20 to 80)
Seal Materials Fluorocarbon FKM and nitrile
Flow Coefficient (Cv) 0.49 4.36
Seat Diameter, in. (mm) 0.20 (5.0) 0.45 (11.5)
Weight, lb (kg) 1.7 (0.77) 5.7 (2.6)

Set Pressure and Resealing Pressure

■ Set pressure is the upstream pressure at which the first
indication of flow occurs. Set pressure of each valve after
initial relief is repeatable within ± 5 % at room temperature.
■ Resealing pressure is the upstream pressure at which there
is no indication of flow. Resealing pressure is always lower
than set pressure. See table below for details.
■ Blowdown is the difference between the set pressure
and the resealing pressure. It is usually expressed as a
percentage of the set pressure.
Minimum Resealing
Set Pressure Pressure as a Percentage
psig (bar) of Set Pressure, %
2900 (200) 95
1450 (100) 90
724 (50.0) 85
362 (25.0) 80

Testing Cleaning and Packaging

Every PRV series proportional safety relief valve is tested for All Swagelok PRV series proportional safety relief valves are
shell, set, and resealing performance. cleaned and packaged in accordance with Standard Cleaning
and Packaging (SC-10), MS‑06‑62.
4 PRV Series Proportional Safety Relief Valves

Materials of Construction
PRV6 Series Relief Valve
PRV2 Series Relief Valve
1
1
2
2
3
3 9
4
10 11 11
4 12
5
5
6
6 15
7 14 14
15 7 17
17 16 18 16

8
13 8
9
19 12
13
19

12
20

Material Grade /
Component ASTM Specification
1 Cover 316L SS / A479, EN10088
2 Set screw A2-70
3 Nut A2
4 Spring housing 316L SS / A479
5 Ball 420 stainless steel
6 Spring guide 316L SS / A479
7 Set spring CR50V4
8 Poppet 316L SS / A479, EN10088
9 Bearing Carbon- and PTFE-filled polyamide
10 Backup ring (PRV2 only) PTFE
11 O-ring
Nitrile, fluorocarbon FKM
12 O-ring
13 Poppet housing
316L SS / A479, EN10088
14 Seat ring
15 Seat seal
Nitrile, fluorocarbon FKM
16 O-ring
17 Seat
18 Seat housing (PRV6 only)
316L SS / A479, EN10088
19 Body
20 Adapters (PRV6 only)
Molybdenum disulfide-based dry
Lubricants
film and paste; silicone-based
Wetted components listed in italics.
 PRV Series Proportional Safety Relief Valves 5

Flow Data at 70°F (20°C)

PRV2 Series PRV6 Series
Flow rates are based on testing of PRV2 series valves with Flow rates are based on testing of PRV6 series valves with
1/4 in. female NPT end connections. 3/4 in. female ISO/BSP end connections.

Set Pressure—0 to 2175 psig (0 to 150 bar) Set Pressure—0 to 750 psig (0 to 50 bar)

Air Flow, Nm3/h Air Flow, Nm3/h

0 150 300 450 600 750 900 0 75 150 225 300 375 450
3000 750 50
200

2500 625
40
Inlet Pressure, psig

Inlet Pressure, psig

Inlet Pressure, bar

Inlet Pressure, bar

150
2000 500
30
1500 100 375 USA
20
1000 250
50
10
500 125

0 0 0 0
0 100 200 300 400 500 600 0 50 100 150 200 250 300

Air Flow, std ft3/min Air Flow, std ft3/min

Set Pressure—2175 to 5290 psig (150 to 365 bar) Set Pressure—1000 to 3000 psig (70 to 200 bar)

Air Flow, Nm3/h Air Flow, Nm3/h

0 150 300 450 600 750 900 0 150 300 450 600 750 900
6000 3000
400 200

5000 2500
0 100 200 300 400 500 600 160
Inlet Pressure, psig

Inlet Pressure, psig

Inlet Pressure, bar

Inlet Pressure, bar

300
3000
4000
200 2000 0 50 USA
100 150 200 250 300
750
120
50
2500 1500
3000 200
150 625
80
2000 40
1000
2000
100 500
40
100
1000
1500 500
30 EURO
375
0 01000 0
20
0
50 0 100 200 300 400 500 600 0 100 200 300 400 500 600 250
500
Air Flow, std ft3/min 10
Air Flow, std ft3/min
125
0 0
0 150 300 450 600 750 900 0 0
Certified Discharge Coefficient Set Pressure—3000
0 75 150 to 6000
225 psig
300(200 375
to 413 450
bar)
Certified Discharge Coefficient (Kdr) Air Flow, Nm3/h
Set Pressure 0 150 300 450 600 750 900
PRV2 Series PRV4/6/8 Series
Range 6000
400
psig (bar) Gas Liquid Gas Liquid 0 100 200 300 400 500 600
5500 3000
145 to 580 200
Inlet Pressure, psig

0 40.0)
(10.0 to 100 200 300 400 500 600 350 Inlet Pressure, bar
6000 5000 2500
400
580 to 1160 160
0.035 0.032 0.027 0.050
(40.0 to 80.0) 5000 4500 2000
300
1160
20 to 2175
300 120
(80.0 to 150) 4000 4000 1500
EURO 250
2175 to 4060 3000
80
3500 1000
15
200
(150 to 280)
0.070 0.032 0.027 0.036
5.0
40
JPN
4060 to 5290 2000 3000 500
(280
10 to 365)
100 4.0 0 100 200 300 400 500 600
1000 0 0
5290 to 6000 Air Flow, std ft3/min
— — 0.027 0.036 0 150 300 450 600 750 900
(365 to 413) 3.0
5.00 0
0 150 300 450 600 750 900
2.0
0
0 3000 6000 9000 12 000 15 000
1.0

0
0 2000 4000 6000 8000

0 100 200 300 400 500 600

6000
400
6 PRV Series Proportional Safety Relief Valves

Dimensions
Dimensions are for reference only and are subject to change.

End Connections Dimensions, in. (mm)

Inlet / Outlet Size A B C D Dia 0.10 in.
(2.5 mm)
PRV2 Series lock wire
hole
Female NPT 6.13 1.18 0.91 2.05
1/4 in.
Female ISO/BSP parallel thread (156) (30.0) (23.0) (52.0)

PRV6 Series
9.89 2.62 2.22
Male ISO/BSP parallel thread 1/2 in. A
(252) (66.5) (56.5)
Female NPT 8.87 1.59 1.20
3/4 in. 2.91
Female ISO/BSP parallel thread (226) (40.5) (30.5) (74.0)
Male ISO/BSP parallel thread 9.97 2.70 2.30
1 in.
Female ISO/BSP parallel thread (254) (68.5) (58.5)

C D

PRV6 series valve shown

Ordering Information
Build a PRV series relief valve ordering number by combining the designators in the sequence shown below.

1 2 3 4 5 6 7 8 9
PRV B 2 F - 02 - 0 - V V - Q
1 Series 4 End Connection Thread Style 7 Seal Material
PRV = 6000 psig (413 bar) maximum M = Male V = Fluorocarbon FKM
inlet pressure F = Female N = Nitrile

2 Inlet / Outlet 5 Body Material 8 Seat Seal Material

B = ISO/BSP parallel thread 02 = 316L SS V = Fluorocarbon FKM
N = NPT N = Nitrile
6 Set Pressure Range
3 End Connection Size 0 = 145 to 580 psig (10.0 to 40.0 bar) 9 Options
PRV2 series 1 = 580 to 1160 psig (40.0 to 80.0 bar) Omit designator if option is not
2 = 1/4 in. 2 = 1160 to 2175 psig (80.0 to 150 bar) ordered.
PRV6 series 3 = 2175 to 4060 psig (150 to 280 bar) Q = Independent 3rd party witness
4 = 1/2 in. adapter, 3/4 in. main body PRV2 series testing of set pressure
6 = 3/4 in. 4=4  060 to 5290 psig (280 to 365 bar)
8 = 1 in. adapter, 3/4 in. main body PRV6 series
4=4  060 to 6000 psig (280 to 413 bar)
 PRV Series Proportional Safety Relief Valves 7

Options and Accessories

Spring Kits Poppet Seal Kits
Spring Kit Seal Poppet Seal Kit
Series Basic Ordering Number Series Material Ordering Number
Contact your authorized Fluorocarbon FKM Contact your authorized
PRV2 PRV2
Swagelok representative Swagelok representative
Nitrile
PRV4/6/8 SS-13K-PRV6-
Fluorocarbon FKM PRV4/6/8-02-V V-3K
PRV4/6/8
Nitrile PRV4/6/8-02-NN-3K
PRV4/6/8 spring kits include spring, 302 SS lock wire with
seal, and installation instructions.
PRV4/6/8 poppet seal kits include O-rings, seat seal, poppet,
To order, add the spring designator for the desired set and installation instructions.
pressure range shown below to the basic ordering number.
To order poppet seal kits for PRV series relief valves
Example: SS-13K-PRV6-0 purchased from RHPS B.V. having S numbers lower than
4600, contact your authorized Swagelok representative. For
Spring Set Pressure Ranges
S numbers 4600 and higher, select the kit from the table
Set Pressure Range Spring above.
psig (bar) Designator
145 to 580 psig (10.0 to 40.0 bar) 0 End Connection O-Ring Seals
580 to 1160 psig (40.0 to 80.0 bar) 1 Seal End Connection O-Ring
1160 to 2175 psig (80.0 to 150 bar) 2 Series Material Seal Ordering Number

2175 to 4060 psig (150 to 280 bar) 3 Fluorocarbon FKM FC-90-SL-O-025

PRV4/6/8
PRV2 Series: 4060 to 5290 psig (280 to 365 bar) Nitrile BN-90-SL-O-025
4
PRV4/6/8 Series: 4060 to 6000 psig (280 to 413 bar)
Order one O-ring for each end connection as needed.

Optional Certification
Optional independent third-party witness testing of set
pressure testing is available upon request. To order, add -Q
to the valve ordering number.
Example: PRVB4F-02-0-VV-Q
Additional Products.
■ For additional Swagelok relief valves, see the Proportional ■ For Swagelok pressure gauges, see the Ind)ustrial and
Relief Valves catalog, MS‑01‑141. Process Pressure Gauges catalog, MS-02-170.

■ For Swagelok tube fitting products, see the Gaugeable

Tube Fittings and Adapter Fittings catalog, MS-01-140.

Safe Product Selection Warranty Information

When selecting a product, the total system design must Swagelok products are backed by The Swagelok Limited
be considered to ensure safe, trouble-free performance. Lifetime Warranty. For a copy, visit swagelok.com or contact
Function, material compatibility, adequate ratings, your authorized Swagelok representative.
proper installation, operation, and maintenance are the
responsibilities of the system designer and user.

• WARNING
Do not mix/interchange Swagelok products or
components not governed by industrial design
standards, including Swagelok tube fitting end Swagelok—TM Swagelok Company
connections, with those of other manufacturers. © 2012–2021 Swagelok Company
MS-02-432, RevG, October 2021