JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
CROSBY
Crosby style JOS-E and JBS-E spring loaded API-526
standard pressure relief valves
Introduction
Crosby® Styles JOS-E and JBS-E springloaded pressure relief valves have been
engineered to provide high quality overpressure protection for air, gas, steam,
vapor, liquid and two-phase applications
in an exceptionally rugged, standardized
design to the process and power industries.
Standard sizes are 1 D 2 to 8 T2 10 with
inlet flange ratings of ANSI Cl 150, 300,
600, 900, 1500 and 2500. Standard
outlet flanges are ANSI Cl 150 or Cl 300
depending on valve size or rating. Inlet and
outlet center-to-face dimensions conform to
API Standard 526, Flanged Steel Pressure
Relief Valves.
Styles JOS-E and JBS-E pressure relief
valves are manufactured in accordance
with ASME Pressure Vessel Code, Section
VIII and capacities are certified by the
National Board of Boiler and Pressure
Vessel Inspectors.
All Crosby pressure relief valve castings
and forgings are procured to ASME/ASTM
material specifications and are available in
a number of material combinations such
as Monel®, Hastelloy® and stainless steel.
In addition, Styles JOS-E and JBS-E relief
valves offer a number of special material
combinations such as Titanium, Duplex
Stainless Steel and Inconel®, and are
available on application.
Dimensions of flanges conform to current
ANSI Standards. All steel raised face
flanges are spiral concentric serrated finish
with 45 to 55 grooves per inch and a finish
between 125 Ra and 200 Ra. Other flange
facings, such as Ring Type Joint, are
available on request.
For information pertaining to sizing and
selection, refer to the AGC SafetySize
computer sizing program and Pressure
Relief Valve Engineering Handbook
(Technical Document No. TP-V300).
Technical Data
Sizes
Orifices
Inlet Ratings
Temperature Range
Pressure Range
:1” D 2” to 8” T2 10”
:0.110 to 27.872 in2 [71 to 17981 mm2]
:ANSI Cl 150, 300, 600, 900, 1500, 2500
:-450°F to +1000°F [-268°C to +538°C]
:JOS-E and JLT-JOS-E: 15 to 6000 psig [1.03 to 413.79 barg] JBS-E and
JLT-JBS-E: 25 to 6000 psig [1.72 to 413.79 barg]
Notes
1.Monel® and Inconel® are registered
trademarks of the International Nickel
Company, Inc.
2.Hastelloy® is a registered trademark of
Haynes International, Inc.
www.pentair.com/valves
Pentair reserves the right to change the content without notice
AGCDR-0053-EN-1307
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Style JOS-E
Valve Styles
Extended service life, reduced cost of ownership superior application versatility
• Improved, rugged nozzle ring design.
• Improved disc insert retention for ease of maintenance.
• Standard Inconel 625 bellows and flange material for superior corrosion resistance, longer
service life and a wider range of applications.
• Universal disc holder allows for simple and cost-effective conversions from conventional to
balanced bellows design.
• Standard threaded bellows design for ease of maintenance and conversion from conventional to
balanced bellows design.
• Improved corrosion resistance with standard 316 stainless steel adjusting bolt locknut and nozzle
ring set screw materials.
• Style JLT capacities certified on liquids and gas.
• Improved parts interchangeability - regardless of top construction.
• Field proven style JLT trim* for stable, non-chattering operation on liquid and gas service.
• Standard chrome steel spring for -20°F to +650°F [-28°C to +343°C].
• Easily converted to any type cap or lifting lever construction, liquid trim, soft-seat or balanced
bellows configurations.
• Full compliance with ASME boiler and Pressure Vessel Code Section VIII and API Standards 526
and 527.
*Patented
These design improvements and material upgrades, combined with state-of-the-art manufacturing
facilities, result in lower cost of ownership to end users and enhanced product availability from
Crosby factories as well as Crosby’s extensive network of pressure management centersSM .
Pentair reserves the right to change the contents without notice
page 2
JOS-E JBS-E JBS-BP-E JOS-H-E
JLT-JOS-E
JLT-JBS-E
JLT-JBS-BP-E
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JOS-E and JBS-E product features
Figure 1
Figure 2
Bellows and top flange
Crosby Styles JBS-E and JLT-JBS-E balanced bellows pressure relief valves provide optimum
valve performance when the developed back pressure in exhaust systems or discharge manifolds
becomes excessive.
All standard JBS-E and JLT-JBS-E relief valves feature a standard bellows and top flange
(Figure 1) manufactured from Inconel alloy 625 which is a fatigue-resistant material and provides
improved corrosion resistance compared to 316L stainless steel bellows. Inconel® alloy 625 is highly
resistant to pitting, crevice corrosion and intergranular attack. The standardization of Inconel® Alloy
625 bellows and top flange provides a higher degree of corrosion resistance without the premium
extra charge usually associated with Inconel® bellows.
Ease of maintenance and component interchangeability
The disc insert retention, disc holder and nozzle ring of the JOS-E and JBS-E have been
re-engineered to improve maintenance, minimize spare parts and provide more component part
interchangeability. (Figure 2)
The disc insert is inserted into the disc holder with a retention clip which is compressed as it passes
through the smallest diameter in the disc holder recess and then returns to its normal shape once
it has passed through. With the retention clip in its original shape, the disc insert is held securely in
place.
A “universal” disc holder allows for simple and cost effective conversions from conventional to
balanced bellows design as well as cost-effective bellows replacement. The bellows threads on to
the disc holder with a tailpiece and gasket.
The new nozzle ring encloses the adjustment slot at the bottom of the ring giving a more rugged,
durable design.
Chrome steel spring
Standard chrome steel spring material for applications with inlet temperatures up to 650°F [343°C].
Figure 3
Dual Certification
Crosby patented Style JLT (Figure 3) pressure relief valves offer a significant increase in capacity
at 10% overpressure resulting in the economic use of a smaller valve as well as a reduction in inlet
and discharge piping costs. The JLT trim is a field-proven patented design providing stable, nonchattering operation for liquid service.
The JLT design is also capacity certified on gas and vapor service and can be applied in two-phase
flow applications. The JLT design is a logical choice for applications where the process fluid may be
a liquid or a gas depending on the overpressure condition.
Bellows Convertibility
The Crosby flanged, spring operated pressure relief valve is designed and manufactured as a
conventional valve and a balanced bellows valve. The conversion from conventional Styles JOS-E
or JLT-JOS-E in 1 D 2 through 8 T2 10 requires only the addition of a bellows assembly and bellows
tail-piece gasket. No other parts are necessary since all other parts are completely interchangeable.
Figure 4
Notes
1. Reg. U.S. Patent Office for DuPont’s
fluoroelastomer.
2.EPR = Ethylene Propylene Rubber.
3.TFE = Tetrafluoroethylene.
4.Reg. U.S. Patent Office for DuPont’s
perfluoroelastomer parts.
5.Registered Trademark of Greene, Tweed &
Co.
6.Registered Trademark of Asahi Glass
Company, Ltd.
Seat Design
Styles JOS-E and JBS-E relief valves are available with flat metal-to-metal seats or soft seats.
The JOS-E and JBS-E two-piece disc holder/disc insert construction provides thermal balancing
assuring maximum seat tightness, and meets the requirements of API Standard 527, Seat
Tightness of Pressure Relief Valves.
Where system operating conditions permit, soft seat or elastomer seat construction is available as
an option. The Crosby O-ring soft seat (Figure 4) is a two-seat design, with a metal-to-metal seat
located downstream of the soft seat. The O-ring is the primary seal. The secondary flat metal-tometal seat controls the compression of the O-ring and also serves as a secondary seal should the
O-ring be damaged.
Standard O-ring materials include Viton®1, BUNA-N, EPR2, TFE3, Silicone Rubber and Kalrez4.
Pressure and temperature limits of each material are shown on page 11. Other soft seat materials
such as Chemraz5 and Aflas6 are available on application.
Cap, Lifting Lever and Spindle Interchangeability
All Crosby JOS-E and JBS-E relief valves use a threaded spindle and drilled and tapped bonnet
which permits easy cap or lifting lever conversions, with maximum standardization and
interchangeability of parts. In addition, standard cap and lifting lever designs can be used with
in-line test devices.
Pentair reserves the right to change the contents without notice
page 3
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JOS-E and JLT-JOS-E conventional pressure relief valves
Crosby Styles JOS-E and JLT-JOS-E are the standard conventional relief valve designs for
applications when the discharge is to the atmosphere or when the discharge is to a low pressure
exhaust system designed to contain the process fluid. Valves subject to flashing fluids may require
a balanced bellows type valve (see page 6).
This exceptionally rugged design features a high guiding surface ratio, corrosion resistant trim,
upgraded materials of construction and several other design improvements to ensure ease of
maintenance as well as a greater degree of parts interchangeability.
For liquid service applications, Style JLT-JOS-E relief valves provide stable operating performance
using the widely industry recognized liquid trim design patented by Crosby. The disc holder in the
liquid trim design has been engineered to allow the valve to achieve full lift at 10% overpressure
without valve chatter.
Styles JOS-E and JLT-JOS-E standard materials of construction
Ref. No.
Part Name 1
Body (JOS-E and JLT-JOS-E ( )5 and ( )6) 1
Body (JOS-E and JLT-JOS-E ( )7) 2
Nozzle 3
Nozzle Ring 4
Set Screw 5
Disc Holder 8
Disc Insert1 9
Retention Clip2 12
Retainer Screws 11
O-ring Retainer 10O-ring1 15
Guide 16
Spindle 17
Spindle Cotter Pin 18
Spring (JOS-E and JLT-JOS-E ( )5) 18
Spring (JOS-E and JLT-JOS-E ( )6 and ( ) 7) 19
Spring Washers 20
Bonnet (JOS-E and JLT-JOS-E ( )5 and ( )6) 20
Bonnet (JOS-E and JLT-JOS-E ( )7) 21
Bonnet Stud 22
Bonnet Stud Nut 24
Adjusting Bolt 25
Adjusting Bolt Nut 26
Pipe Plug (Bonnet) 27
Set Screw Gasket1
28
Guide Gasket1
34
Seal and Wire 35
Seal Clip (Not Shown) 36
Nameplate (Not Shown) 40
Threaded Cap 41
Cap Gasket1
Standard Material
ASME SA216 GR. WCB
ASME SA217 GR. WC6
316 Stainless Steel
316 Stainless Steel
316 Stainless Steel
316L Stainless Steel
316 Stainless Steel
Inconel® X750
316 Stainless Steel
316 Stainless Steel
Specify
ASTM A297 GR. HE SST
416 Stainless Steel
Stainless Steel
Chrome Steel3
Alloy Steel 3,4
Carbon Steel
ASME SA216 GR. WCB
ASME SA217 GR. WC6
ASME SA193 GR. B7
ASME SA194 CL 2H
316 Stainless Steel5
316 Stainless Steel
Carbon Steel
Organic Fiber Non-Asbestos
Organic Fiber Non-Asbestos
Lead and Stainless Steel
Stainless Steel
Stainless Steel
Carbon Steel
Organic Fiber Non-Asbestos
Notes
1. Recommended Spare Part.
2.Furnished with Disc Insert.
3.Corrosion resistant coating.
4.Crosby may upgrade to Inconel® X750.
5.Class 900#, 1500# and 2500# inlet ratings
use 416 Stainless Steel.
Pentair reserves the right to change the contents without notice
page 4
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JOS-E and JLT-JOS-E conventional pressure relief valves
Style JLT-JOS-E
(with O-ring seat)
Style JOS-E
(with metal-to-metal seat)
Pentair reserves the right to change the contents without notice
page 5
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JBS-E and JLT-JBS-E balanced bellows construction
Crosby Styles JBS-E and JLT-JBS-E are pressure relief valves incorporating a bellows which is
balanced to minimize the effect of back pressure on the performance characteristics. The balanced
bellows design offsets the effects of variable back pressure on valve set pressure. The balanced
bellows valve can also handle applications involving high built-up back pressure.
Additionally, the bellows serves to isolate the guide, spindle, spring and other parts contained in
the bonnet chamber from corrosive fluids or media such as a highly viscous fluid or slurry which
could render the relief valve inoperative.
For liquid service applications, Crosby offers Style JLT-JBS-E relief valves.
The standard bellows assembly of the Crosby Style JBS-E and JLT-JBS-E threads onto the disc
holder with a bellows tailpiece and gasket. A welded bellows attachment is available as an option.
The JBS-E and JLT-JBS-E bellows and bellows flange are supplied in Inconel 625 as standard
material for improved durability, corrosion resistance and service life.
Styles JBS-E and JLT-JBS-E standard materials of construction
Ref. No.
Part Name Standard Material
1
Body (JBS-E and JLT-JBS-E ( )5 and ( )6) ASME SA216 GR. WCB
1
Body (JBS-E and JLT-JBS-E ( )7) ASME SA217 GR. WC6
2
Nozzle 316 Stainless Steel
3
Nozzle Ring 316 Stainless Steel
4
Set Screw 316 Stainless Steel
5
Disc Holder 316L Stainless Steel
6C
Bellows Flange1Inconel® 625
6BBellows1Inconel® 625
6A
Bellows Tailpiece1
316L Stainless Steel
29
Tailpiece Gasket2 Organic Fiber Non-Asbestos
8
Disc Insert2 316 Stainless Steel
9
Retention Clip3 Inconel® X750
12
Retainer Screws (see page 5) 316 Stainless Steel
11
O-ring Retainer (see page 5)
316 Stainless Steel
10O-ring2 (see page 5)
Specify
15
Guide ASTM A297 GR. HE SST
16
Spindle 416 Stainless Steel
17
Spindle Cotter Pin Stainless Steel
18
Spring (JBS-E and JLT-JBS-E ( )5) Chrome Steel4
18
Spring (JBS-E and JLT-JBS-E ( )6 and ( )7) Alloy Steel4,5
19
Spring Washers Carbon Steel
20
Bonnet (JBS-E and JLT-JBS-E ( )5 and ( )6) ASME SA216 GR. WCB
20
Bonnet (JBS-E and JLT-JBS-E ( )7) ASME SA217 GR. WC6
21
Bonnet Stud ASME SA193 GR. B7
22
Bonnet Stud Nut ASME SA194 CL 2H
24 Adjusting Bolt 316 Stainless Steel6
25
Adjusting Bolt Nut 316 Stainless Steel
27
Set Screw Gasket1 Organic Fiber Non-Asbestos
28
Guide Gasket2 Organic Fiber Non-Asbestos
34
Seal and Wire Lead and Stainless Steel
35
Seal Clip (not shown) Stainless Steel
26
Nameplate (not shown) Stainless Steel
40
Threaded Cap Carbon Steel
41
Cap Gasket2 Organic Fiber Non-Asbestos
Notes
1.Subassembly.
2.Recommended Spare Part.
3.Furnished with Disc Insert.
4.Corrosion resistant coating.
5.Crosby may upgrade to Inconel® X750.
6.Class 900#, 1500# and 2500# inlet ratings
use 416 Stainless Steel.
Pentair reserves the right to change the contents without notice
page 6
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JBS-E and JLT-JBS-E balanced bellows construction
Note
This vent must
remain open on
JBS-E and
JLT-JBS-E
construction
Style JBS-E
(with metal-to-metal seat)
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page 7
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JOS-E and JLT-JOS-E
Conventional pressure relief valves for sour gas service per NACE MR0175
Level 1
For applications where compliance with NACE MR0175 is required for wetted parts in the primary
(upstream) pressure zone of the pressure relief valve. Materials of construction for Level 1 can be
found on page 4 and 5.
Level 2
For applications where compliance with NACE MR0175 is required for wetted parts in the primary
(upstream) and secondary (downstream) pressure zones of the pressure relief valve.
While the materials recommended for the Crosby Style JOS-E and JLT-JOS-E sour gas valves
are suitable for average service conditions, optional materials are available to provide additional
resistance to corrosion beyond the minimum requirements of the standard.
Material specification
Ref No. Part Name Standard NACE Material Level 2
1
2
3
4
5
8
9
15 16 17 18 19 20 21 22 24 25 26 27 28 34 35 40 41 Body Nozzle Nozzle Ring Set Screw Disc Holder Disc Insert Retention Clip Guide Spindle Spindle Cotter Pin Spring Spring Washer Bonnet Bonnet Stud Bonnet Stud Nut Adjusting Bolt Adjusting Bolt Nut Pipe Plug (Bonnet) Set Screw Gasket Guide Gasket Seal and Wire Seal Clip (not shown) Threaded Cap Cap Gasket ASME SA216 GR WCB
316 Stainless Steel
316 Stainless Steel
316 Stainless Steel
316L Stainless Steel
316 Stainless Steel
Inconel® X750
ASTM A297 GR. HE SST
316 Stainless Steel
Stainless Steel
Inconel® X750
316 Stainless Steel
ASME SA216 GR WCB
Alloy Steel1
Alloy Steel1
316 Stainless Steel
316 Stainless Steel
Carbon Steel
Organic Fiber Non-Asbestos
Organic Fiber Non-Asbestos
Lead and Stainless Steel
Stainless Steel
Carbon Steel
Organic Fiber Non-Asbestos
Bold materials indicate variation from standard product.
Style JOS-E
Notes
1.If Class I or II bolting is required, bonnet
studs will be ASME A193 Gr B7M HRC-22
maximum and bonnet stud nuts will be
ASME A194 Class 2HM HRC-22 maximum.
Pentair reserves the right to change the contents without notice
page 8
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Styles JBS-E and JLT-JBS-E
Balanced bellows pressure relief valves for sour gas service per NACE MR0175
Level 1
For applications where compliance with NACE MR0175 is required for wetted parts in the primary
(upstream) pressure zone of the pressure relief valve. Materials of construction for Level 1 can be
found on page 6 and 7.
Level 2
For applications where compliance with NACE MR0175 is required for wetted parts in the primary
(upstream) and secondary (downstream) pressure zones of the pressure relief valve. The Inconel®
625 bellows isolates the valve spring and other critical components above it from the process fluid.
While the materials recommended for the Crosby Style JBS-E and JLT-JBS-E sour gas valves
are suitable for average service conditions, optional materials are available to provide additional
resistance to corrosion beyond the minimum requirements of the standard.
Material specification
Style JBS-E
(with bellows)
Ref No. Part Name 1
2
3
4
6C
6B 6A 29 5
8
9
15 16 17 18 19 20 21 22 24 25 27 28 34 35 40 41 Body ASME SA216 GR. WCB
Nozzle 316 Stainless Steel
Nozzle Ring 316 Stainless Steel
Set Screw 316 Stainless Steel
Bellows Flange1 Inconel® 625
Bellows1Inconel® 625
Bellows Tailpiece1 316L Stainless Steel
Tailpiece Gasket Organic Fiber Non-Asbestos
Disc Holder 316L Stainless Steel
Disc Insert 316 Stainless Steel
Retention Clip Inconel® X750
Guide ASTM A297 GR. HE SST
Spindle 416 Stainless Steel
Spindle Cotter Pin Stainless Steel
Spring Chrome Steel-Aluminum Metallized
Spring Washer Steel
Bonnet ASME SA216 GR. WCB
Bonnet Stud Alloy Steel2
Bonnet Stud Nut Steel2
Adjusting Bolt 316 Stainless Steel3
Adjusting Bolt Nut 316 Stainless Steel
Set Screw Gasket Organic Fiber Non-Asbestos
Guide Gasket Organic Fiber Non-Asbestos
Seal and Wire Lead and Stainless Steel
Seal Clip (not shown) Stainless Steel
Threaded Cap Carbon Steel
Cap Gasket Organic Fiber Non-Asbestos
Standard NACE Material Level 2
Bold materials indicate variation from standard product.
Notes
1.Subassembly.
2.If Class I or II bolting is required, bonnet
studs will be ASME A193 Gr B7M HRC-22
maximum and bonnet stud nuts will be
ASME A194 Class 2HM HRC-22 maximum.
3.Class 900#, 1500# and 2500# inlet ratings
use 416 Stainless Steel.
Pentair reserves the right to change the contents without notice
page 9
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Caps and lifting levers
Cap
Dog shaft
Packing gland sleeve
Packing gland nut
Packing
Spindle
Cap
Seal
and
wire
Lever nut
Lever nut
lockwasher
Lever
Packing
gland
Dog shaft
gasket
Test rod
Cap plug
Cap gasket
Cap or
cap top
Threaded Cap
Cap plug
gasket
Type A
Type J
(standard)
Packed lifting lever
Type D
(Top view of packing gland construction
used for special materials)
Spindle
Lever nut
Cap test rod
Lockwasher
Type B - Threaded cap
Type E - Packed lifting lever
Type H - Bolted cap
Type K - Threaded cap (standard)
Type M- Bolted cap (standard)
Cap
Cap
Spindle
Lever
Dog shaft bearing
Dog
shaft
O-ring
Gasket
Cap
Cap stud nut
Cap stud
Dog
Seal and
wire
Bolted Cap
Packed lifting lever
Type G
Type L
(standard)
Spindle nut
Valve
spindle
Type D
(Top view)
Cap
Cotter pin
Forked lever
Cap top
Cotter pin
Spindle nut
Cap top
gasket
Dog
Dog
shaft
Cotter pin
Cap
Pin
Pin
Cap set
screw
Spindle
Adjusting
bolt
Adjusting
bolt nut
Cap stud
Cap stud nut
Lever
Seal and wire
Regular lifting lever
Packed lifting lever
Type C
Type D
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page 10
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Kalrez ® (80)
O-Ring soft seat materials and pressure/temperature limits
Kalrez ® (90)
Viton ® (90)
TFE
BUNA-N (70)
EPR (80)
Kalrez ® (80)
Silicone (70)
Viton ® (75)
TFE
BUNA-N (70)
EPR (70)
TFE
Inlet temperature °C
Silicone (50)
Viton ® (75)
Kalrez ® (80)
Silicone (50)
Kalrez ® (80)
Silicone (80)
Viton ® (75)
TFE
BUNA-N (50)
EPR (70)
Inlet temperature °F
Viton ® (75)
Kalrez ® (90)
TFE
BUNA-N (90)
EPR (90)
Kalrez ® (90)
Viton ® (90)
TFE
Silicone (70)
TFE
BUNA-N (90)
EPR (90)
TFE
Silicone (80)
TFE
TFE
Set pressure, psig
Figures in ( ) are Durometer Hardness specifications
Maximum set pressure limits
Maximum Set Pressure
Orificepsig barg
D
1480 102
E
1480 102
F
1480 102
G
1480 102
H
1480 102
J
1480 102
K
1480 102
L
1000 68.9
M
1100 75.8
N
1000 68.9
P
1000 68.9
Q
600 41.3
R
300 20.6
T
300 20.6
T2 300 20.6
1480 or max. set pressure
rating of the O-ring soft seat valve
Notes
• EPR = Ethylene Propylene Rubber
TFE = Tetrafluoroethylene
• Other soft seat materials are available on request. For O-ring seats below -150°F
[-101°C] consult Crosby. For steam service, metal-to-metal seats are recommended consult
Crosby if soft seats are required.
JBS-E O-Ring
Soft Seat
Pentair reserves the right to change the contents without notice
JLT-JOS-E O-Ring
Soft Seat
page 11
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Crosby Styles JBS-E and JLT-JBS-E balanced bellows valves with supplementary
back pressure balancing piston
Styles JBS-BP-E and JLT-JBS-BP-E are a modification to the Crosby bellows pressure relief valve
designed and tested in collaboration with engineers of one of the world’s leading petroleum
companies. This adaptation provides additional assurance of safe performance in the event of
bellows failure on installations having discharge manifold systems where back pressures (constant
or variable) are present.
The Crosby bellows pressure relief valve (Styles JBS-E and JLT-JBS-E) was especially developed
for service under back pressure conditions. The balanced area bellows counteracts back pressure
effects. However, in case of a broken or ruptured bellows, the valve would perform in the manner
of a standard valve without bellows. Introduction of the Supplementary Back Pressure Balancing
Piston guarantees full performance characteristics of the valve until necessary replacement of the
bellows can be made. This design, illustrated on the right, thus affords double protection.
Unless compensated for, the effects of back pressure may cause (1) a change in the opening
pressure, (2) a decrease in valve capacity, and (3) valve performance to become unstable at higher
back pressure. Use of the bellows valve with supplementary balancing piston maintains the
balancing effect even after bellows failure and in such event would allow the valve to function in
essentially the same manner as with the bellows intact. However, the bonnet of the valve must be
vented in order to insure proper functioning of the valve. The vent also serves for a tell-tale in case
of a ruptured or broken bellows.
Design
The auxiliary balancing piston is incorporated in the basic bellows valve,
modified to include the piston (5B) and the cylinder (17) which is part of the
disc holder. The guiding clearances are held to a minimum and, in addition,
grooves in the piston form a labyrinth seal to reduce flow between the piston
and cylinder. Thus, in the event of a bellows failure, the leakage of fluid to
atmosphere is kept to a minimum.
Styles JBS-BP-E
and JLT-JBS-BP-E
Crosby BlockBody™ Pressure Relief Valves
Crosby’s BlockBody Pressure Relief Valves provide the solution to applications involving very high
set and back pressures that exceed standard ranges.
One single Crosby BlockBody Pressure Relief Valve installation can handle the capacity of multiple
API-526 standard valves with:
• Fewer potential leak
• Fewer spare parts required paths
• Cost savings on inlet and outlet piping
Design Details:
• Full nozzle design for maximum tightness
• Geometrically designed valve BlockBody and bonnet for weight savings
• Interference fitted inlet studs provided
• Available in orifice sizes from “D” through “T2”
• Materials of construction available for special process applications
• Available in Crosby Styles JOS-E, JBS-E and JLT-E valve designs
For more details please refer to datasheet AGCDR-0043.
Pentair reserves the right to change the contents without notice
page 12
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Dimensions and Weights (carbon steel types only) Metric Units
Connection
Size & Rating
Inlet x Outlet
Orifice
E
H
E
X
F
Notes
1. Pressure and temperature ratings are per
API-526.
2.Height shown “H” is for Standard Type J
threaded Cap.
3.Pre 1995 API-526 2 1/2” Connections
available for D, E, F, G and J orifice in place
of current 3” size.
* Lightweight CI 300 rating per API -526
(Cl 150 rated body).
1”-150 x 2”-150”
D,E
1”-300 x 2”-150” *
1”-300 x 2”-150”
1”-600 x 2”-150”
1 1/2”-900 x 2”-300”
1 1/2”-1500 x 2”-300”
1 1/2”-2500 x 3”-300”
1 1/2”-150 x 2”-150”
F
1 1/2”-300 x 2”-150” *
1 1/2”-300 x 2”-150”
1 1/2”-600 x 2”-150”
1 1/2”- 900 x 3”-300”
1 1/2”-1500 x 3”-300”
1 1/2”- 2500 x 3”-300”
1 1/2”-150 x 3”-150”
G
1 1/2”-300 x 3”-150” *
1 1/2”-300 x 3”-150”
1 1/2”-600 x 3”-150”
1 1/2”-900 x 3”-300”
2”-1500 x 3”-300 “
2”-2500 x 3”-300”
1 1/2”-150 x 3”-150”
H
1 1/2”-300 x 3”-150” *
2”-300 x 3”-150”
2”-600 x 3”-150”
2”-900 x 3”-150”
2”-1500 x 3”-300 “
2”-150 x 3”-150”
J
2”-300 x 3”-150” *
3”-300 x 4”-150”
3”-600 x 4”-150”
3”-900 x 4”x 150”
3”-1500 x 4”-300”
3”-150 x 4”-150”
K
3”-300 x 4”-150” *
3”-300 x 4”-150”
3”-600 x 4”-150”
3”-900 x 6”x 150”
3”-1500 x 6”-300”
3”-150 x 4”-150”
L
3”-300 x 4”-150” *
4”-300 x 6”-150”
4”-600 x 6”-150”
4”-900 x 6”-150”
4”-1500 x 6”-300”
4”-150 x 6”-150”
M
4”-300 x 6”-150” *
4”-300 x 6”-150”
4”-600 x 6”-150”
4”-900 x 6”-150”
4”-150 x 6”-150”
N
4”-300 x 6”-150” *
4”-300 x 6”-150”
4”-600 x 6”-150”
4”-150 x 6”-150”
P
4”-300 x 6”-150” *
4”-300 x 6”-150”
4”-600 x 6”-150”
6”-150 x 8”-150”
Q
6”-300 x 8”-150” *
6”-300 x 8”-150”
6”-600 x 8”-150”
6”-150 x 8”-150”
R
6”-300 x 8”-150” *
6”-300 x 10”-150”
6”-600 x 10”-150”
8”-150 x 10”-150”
T
8”-300 x 10”-150” *
8”-300 x 10”-150”
8”-300 x 10”-150”
104,8
104,8
104,8
104,8
104,8
104,8
139,7
123,8
123,8
123,8
123,8
123,8
123,8
139,7
123,8
123,8
123,8
123,8
123,8
155,6
155,6
130,2
130,2
130,2
154
154
154
136,5
136,5
184,1
184,1
184,1
184,1
155,6
155,6
155,6
184,1
198,4
196,8
155,6
155,6
179,4
179,4
196,8
196,8
177,8
177,8
177,8
177,8
196,8
196,8
196,8
196,8
196,8
181
181
225,4
225,4
239,7
239,7
239,7
239,7
240
240
240
240
276,2
276,2
276,2
276,2
Dimensions
mm
F
H
X
114,3
114,3
114,3
114,3
139,7
139,7
177,8
120,6
120,6
152,4
152,4
165,1
165,1
177,8
120,6
120,6
152,4
152,4
165,1
171,5
171,5
123,8
123,8
123,8
161,9
161,9
161,9
123,8
123,8
181
181
171,4
181
161,9
161,9
161,9
181
215,9
215,9
165,1
165,1
181
203,2
222,2
222,2
184,1
184,1
184,1
203,2
222,2
209,5
209,5
209,5
222,2
228,6
228,6
254
254
241,3
241,3
241,3
241,3
241
241
267
267
279,4
279,4
279,4
279,4
Pentair reserves the right to change the contents without notice
502
502
502
502
521
521
552
591
591
591
591
584
584
679
591
591
591
591
660
686
686
597
597
597
679
718
718
603
603
726
777
826
826
756
756
756
838
991
991
864
864
864
895
1010
1010
851
851
914
1067
1086
1099
1099
1099
1099
1080
1124
1181
1213
1213
1213
1213
1314
1353
1353
1353
1353
1511
1511
1511
1511
40
40
40
40
51
51
64
44
44
44
44
51
51
64
44
44
44
44
51
70
70
43
43
46
46
59
59
43
43
68
68
68
68
54
54
54
54
68
68
51
51
54
60
75
75
54
54
54
62
65
54
54
54
60
54
54
54
65
59
59
59
75
59
59
59
70
65
65
65
65
Approx.
Weight
kg
16
16
16
16
28
28
34
23
23
23
23
29
29
39
23
23
23
27
40
90
90
25
25
27
34
50
50
30
30
40
52
64
70
52
52
52
73
84
88
69
69
87
103
122
122
91
91
101
120
132
118
118
127
135
122
122
130
182
218
218
223
256
256
256
273
286
400
400
409
422
page 13
JOS-E, JBS-E,JLT-JOS-E, JLT-JBS-E Pressure Relief Valve
Style designations
Size
Inlet x Orifice
x Outlet
1” D 2”
thru
8” T2 10”5
Style
Pressure/Temperature
Inlet Flange Range Ratings3
JOS-E
Conventional
1 - Cl 150 Flange
JBS-E
With bellows
3 - Cl 300 Flange
JLT-JOS-E
Conventional with
liquid trim1
5 - Cl 900 Flange
JLT-JBS-E
Bellows with liquid
trim1
JBS-BP-E
Bellows with back
pressure balancing
piston
JLT-JBS-BP-E
Bellows with liquid
trim and back
pressure balancing
piston1
2 - Cl 300 Flange (A)
4 - Cl 600 Flange (B)
6 - Cl 1500 Flange
7 - Cl 2500 Flange
Note (A) - Lightweight
Cl.300 flange
per API-526
2 - -450°F to -76°F
[-268°C to -60°C]
4 - -75°F to -21°F
[-59°C to -30°C]
5*- -20°F to +650F
[-29°C to +343°C]
Material
Variations4
Seat Type
None - Metal
“OR” - O-Ring
When ordering
soft seats, specify
material.
6 -+651°F to +800°F
[+344°C to +427°C]
None - Standard
Materials
Type J -(Standard)
threaded cap
S
Type K-Threaded cap
with test rod
- All 316 St. St.
S4 -All 316 St. St.
except body,
bonnet, cap and
spring
M
7 - +801°F to +1000°F
[+428°C to +538°C]
- All Monel with
Monel or Inconel
spring
M1 - Monel nozzle
and disc insert
* Except for Style
JOS- H-E with open
Note (B) - Except “T”
bonnet, chrome steel
orifice is Cl.300
spring may be used to
flange
+800°F [+427C°]
M4 - All Monel except
body, bonnet,
cap, spring and
washers
M5 - All Monel except
spring and
washers
JOS-H-E
Conventional JOS
with open bonnet for
ASME Code Section
VIII steam service to
+800°F [+427°C]2
Caps and Lifting
Levers (Type)
H
-All Hastelloy C
H1 - Hastelloy C
nozzle and disc
insert
H4 - All Hastelloy C
except body,
bonnet, cap,
spring and
washers
Type C-Regular lifting
lever6
Type D-Packed lifting
lever6
Type E -Packed lifting
lever with test
rod6
Type L -Bolted cap
Type M- Bolted cap
with test rod
Optional Caps for
Height Restricted
Applications
Type A - Threaded cap
Type B - Threaded cap
with test rod
Type G - Bolted cap
Type H- Bolted cap
with test rod
H5 - All Hastelloy C
except spring
and washers
N2 - NACE Level 2
JOS-E =
Inconel X750
spring, 316 St. St.
washers, spindle and
adjusting bolt
JBS-E =
Aluminum Metallized
Spring
Available options
Notes
• Welded bellows attachment
• Flange facings such as ring type joint
• Sour gas service materials and certifications
• Special Cl 300 outlets (where not standard)
• Special Teflon®* (FEP) bellows coating
• Special spring coatings or plating
• Block bodies
• Bonnet and cap inside painting or plastic coating
• Bug screens
• Special materials not cataloged
• Flanges to international standards
• Special flanges
• Stellited nozzle and disc insert
• Special casting or machined surface tests
• Special cleaning
• Special painting or coatings
• Special testing
• Steam jacketed bodies
• Supplementary loading
1. Style designations “JLT-JOS-E”, “JLTJBS-E”, or “JLT-JBS-BP-E” signify Styles
JOS-E, JBS-E or JBS-BP-E with liquid trim
for liquid service.
2.Upper temperature limit is +800°F [+427°C]
for Style JOS-H-E open bonnet valve for
ASME Code Section VIII steam service.
3.See pages 14 - 43 in Catalog 310 for
appropriate maximum set pressures and
temperatures.
4.See pages 12 - 13 in Catalog 310 for
complete listings of materials of
construction.
5.Larger sizes are available. Ask for Catalog
No. 307.
6.ASME Code Section VIII rules require that
pressure relief valves for water service over
+140°F [+60°C], steam and air shall have a
lifting device.
* Reg. U.S. Patent Office for DuPont’s fluorocarbon resins.
Pentair reserves the right to change the contents without notice
page 14