 |
VENT-SAF™ Explosion Vents |
An explosion can
result from an ignition of a combustible gas, mist or dust when mixed with
air during processing, handling or storage operations. A rapid rise in
pressure occurs in the containing structure, and if it is not of adequate
strength to withstand the deflagration pressure, extensive damage and
injury to personnel can occur.
Explosion vents
are low burst pressure membranes of calculated area fixed over an opening
on the structure to be protected. In the event of a deflagration the vents
provide a rapid and unrestricted opening at a predetermined burst pressure
(Pstat) allowing combustion gases to expand and flow through the open
vent. The required relief area necessary to protect plant or equipment may
be determined by using the most current standards of NFPA 68 or VDI 3673.
The most suitable explosion vent may be selected by matching the
information in this catalog with the particular operating
conditions.
The Vent-Saf®
explosion vents can protect industrial equipment including silos, dust
collectors, cyclones, conveyers, dryers…and many more.
The Vent-Saf
Product Line
Types VSP™
(Vent-Saf Plus ) and VSS™ (Vent-Saf Sanitary) domed single section metal
explosion vents with integral gaskets. The dome is formed to resist
vacuum.
Type VSE™
(Vent-Saf Economy) a flat, single section metal explosion vent with
integral gaskets.
Type EXP/DV™ a
round domed explosion vent of composite construction with integral
gaskets. The EXP/DV vent has a laser cut stitch pattern in the dome area.
A Teflon® liner covers the slits providing a seal. The vent burst pressure
is controlled by the arrangement of the stitch pattern.
The Vent-Saf
vents are available in both round or rectangular styles designed to be
mounted on the structure to be protected using a Safety
Frame.
Features and Benefits
Types VSP, VSS AND VSE
- Unique, economic and
patented design.
- Accurate reliable and
leak tight.
- Enhanced abrasion
resistance.
- One-piece metal
construction without slits on the process side avoiding product
accumulation.
- Optional design for
aseptic/sanitary applications.
- No fragile PTFE seal that
may puncture and admit moisture.
- Superior dynamic
performance due to low mass compared with composite designs.
- Operating pressures up to
60% of the minimum tagged pressure rating (80% under certain
conditions).
- Thermal insulation
available to permit use in operating temperatures to 2000°F/1093°C, to
reduce heat loss or prevent condensation.
- Supplied with integral
gaskets ready for installation.
- Fail-safe design, if
damaged it will provide a relief opening below its rated pressure.
Specification Data
and Ordering Checklist
The items to consider in
selecting and ordering an explosion vent. For an Application Data Sheet
listing required information contact BS&B.
- Product name
(example:VSP).
- Size.
- Positive burst pressure
(Pstat) at coincident temperature.
- Normal operating pressure
and temperature.
- Maximum operating
pressure and temperature.
- Maximum vacuum pressure.
- Process media
compatibility with materials of vent.
- Pressure cycling
conditions.
- Frames (bolted, welded);
panel bolt pattern, BS&B standard or special, please specify.
- Optional insulation
design.
- Optional sanitary/aseptic
design
- Optional magnetic burst
sensor (specify if armored cable or factory installation of switch on
frame is required).
- Optional full gaskets.
- Other special
requirements.
Types VSP & VSS
Burst Pressure
(pstat)Burst pressures are
available from 0.3 psig (0.021 barg) to 5 psig (0.35 barg) depending on
vent size and configuration.
Vacuum
ServiceThe VSP and VSS vents with
their domed constructions are designed to resist high vacuum under cycling
conditions without the need for vacuum support bars attached to the inner
safety Frame. The vacuum rating of a vent is dependent on the vent’s burst
pressure, consult BS&B Safety Systems, Inc or BS&B Safety Systems,
Ltd.
Service
CapabilitiesThe VSP vent has been
tested to over 1 million pressure cycles from vacuum to light positive
pressure while retaining its burst accuracy. The VSP vent exhibits
superior performance compared to conventional composite vents that fatigue
after less than 40,000 pressure cycles under equivalent test
conditions.The type VSS vent is of
similar construction to the type VSP vent and is suitable for static or
cyclic vacuum service conditions only.
Type VSE
Burst Pressure
(pstat)Burst pressure is available
from 0.25 psig (0.017 barg) to 5 psig (0.35 barg) depending on vent size.
The VSE vent will burst at the same pressure in both directions.
Vacuum
ServiceThe VSE must be installed
in a Safety Frame with vacuum support bars in order to withstand vacuum or
back-pressure.
Service
CapabilitiesThe VSE is designed for
atmospheric, or static pressure service conditions.
Round VSE VENTS. There are
two standard designs providing a one petal or four petal shape relief
openings. The four-petal design offers high burst
pressure.
Types VSP, VSS & VSE
Operating Pressure The VSP, VSS and
VSE vents are suitable for positive pressures up to 60% of the minimum
burst pressure. However , under certain conditions up to 80% of the
minimum burst pressure is possible. Consult BS&B Safety Systems,
Inc.
Vent OperationThe perimeter of
the rectangular or square vents are laser cut on three sides in a stitch
pattern. The fourth side acts as a hinge, and retains the central section,
controlling fragmentation upon opening of the vent The laser cut slits in
the vent are covered by integral gaskets or sealing material to achieve a
leak tight sealed construction.
Materials of
ConstructionThe VSP, VSE and
VSS explosion vents in 316SS* standard material are available with a
variety of gasket and seal materials depending on the
application.
|
Gasket
|
Seal
|
Standard
designs’ |
Silicone
sponge
|
Silicone
sponge |
Sanitary/Aseptic Design |
White solid
silicone (FDA)
|
RTV (FDA
approved)
|
High
Temperature Applications(above 300°F,150°C) |
Red Solid
silicone
|
RTV (high
temperature)
|
For economy half
silicone sponge gaskets are provided as standard which cover half the
flange to the bolt holes. Full gaskets may be supplied on request.
Alternative gasket materials including Neoprene and Solid Viton® are also
available.
*Vents are
available in alternative materials.
‘Silicone sponge
component acts as a gasket/seal and is fitted to both sides of the
vent.
Viton® is a
registered trademark of Du Pont Dow Elastomers LLC
Burst
Tolerance
|
Burst
pressure psig (barg)
|
Tolerance
psig (barg) |
|
Type VSP
VSS
|
Type
VSE
|
|
|
Below 1.5
(0.1)
|
Below 1.0
(0.069)
|
+ 0.25
(0.017)
|
|
At or above
1.5 (0.1)
|
At or above
1.0 (0.069)
|
+ 0.5
(0.034)
|
An alternative
tolerance of +/-0.25 % may be offered if required by the customer, contact
us. The tag is affixed to the discharge side of the vent will be marked
with a minimum-maximum burst pressure range.
Rectangular and Round
Explosion Vent Dimensions
The dimensions
and relief areas of VSP and VSE vents in either rectangular or round
designs are given in Tables 1 and 2. Contact BS&B Safety Systems, Inc.
or BS&B Safety Systems, Ltd. for non-standard sizes.
Safety
Frames
Rectangular vents
can be mounted in lightweight angle profile Safety Frames. Round vents can
be installed between standard weld neck flanges in accordance with ANSI
150 or DIN PN10 or in lightweight angle profile frames. Safety frames are
available in 304SS or carbon steel.
The frames are
designed to either bolt or weld on to the equipment to be protected. If
frames are manufactured by the user, details of bolt sizes, spacing and
dimensions must be given to BS&B Safety Systems, Inc. prior to vent
manufacture to ensure correct vent performance.
Operating
Temperature
The standard
explosion vent may be used in temperatures –40°F to 300°F (-40°C to
150°C), the sanitary/aseptic design –80°F to 450°F (-62°C to 232°C) and
with solid silicone gaskets the RTV (High Temperature) seal –80°F to 500°F
(-62°C to 260°C). Alternative vent construction permits higher
temperatures.
Sanitary/Aseptic
Applications
These explosion
vents of single section stainless steel construction with smooth internal
surface finish are free of cavities. Solid White silicone gaskets are
supplied fitted to the vent flange area and FDA approved RTV sealing
material applied to the vent perimeter to achieve a sanitary/aseptic
construction.
Thermal
Insulation
Thermally
insulated vents using either urethane or ceramic material may be offered
to prevent heat loss or condensation on the vent. Insulation will also
permit their use in high temperature service up to 2000°F (1093°C). The
insulation is integral to the panel construction, requiring no additional
field installation. The type and thickness of the insulation material will
be selected to suit the operating temperature requirements. The additional
insulation is taken into consideration when the burst pressure is
determined. An optional stainless steel weather cover is available to
provide added protection of the insulation against rain, ice or
debris.
Burst Sensor
The MBS™ Type
magnetic sensor is available to provide immediate warning upon bursting of
the explosion vent. A magnetic activator is fitted to the vent and a
proximity switch attached to the safety frame. Warning of a burst vent is
given when the current flowing through the sensor is disrupted giving an
open circuit signal. The sensor is suitable for use in hazardous areas
provided a suitable power level or Zener barrier is used to meet
intrinsically safe requirements. An armored style sensor is also
available.
RECTANGULAR
VSP, VSS AND VSE VENT DIMENSIONS
|
Nom.
Size
|
A
|
B
|
C
|
D
|
Net
Relief
|
|
in.
|
in.
|
mm.
|
in.
|
mm.
|
in.
|
mm.
|
in.
|
mm.
|
in.
sq.
|
cm.
sq.
|
|
9.0 x
12.0
|
12.0
|
304.8
|
9.0
|
228.6
|
16.0
|
406.4
|
13.0
|
330.2
|
98
|
631
|
|
12.0 x
18.0
|
18.0
|
457.2
|
12.0
|
304.8
|
22.0
|
558.8
|
16.0
|
406.4
|
201
|
1298
|
|
18.0 x
18.0
|
18.0
|
457.2
|
18.0
|
457.2
|
22.0
|
558.8
|
22.0
|
558.8
|
306
|
1976
|
|
18.0 x
24.0
|
24.0
|
609.6
|
18.0
|
457.2
|
28.0
|
711.2
|
22.0
|
558.8
|
411
|
2653
|
|
18.0 x
30.0
|
30.0
|
762.0
|
18.0
|
457.2
|
34.0
|
863.6
|
22.0
|
558.8
|
516
|
3331
|
|
18.0 x
36.0
|
36.0
|
914.4
|
18.0
|
457.2
|
40.0
|
1016.0
|
22.0
|
558.8
|
621
|
4008
|
|
19.0 x
59.0
|
59.0
|
1498.6
|
19.0
|
482.6
|
63.0
|
1600.2
|
23.0
|
584.2
|
1082
|
6982
|
|
24.0 x
24.0
|
24.0
|
609.6
|
24.0
|
609.6
|
28.0
|
711.2
|
28.0
|
711.2
|
552
|
3563
|
|
24.0 x
30.0
|
30.0
|
762.0
|
24.0
|
609.6
|
34.0
|
863.6
|
28.0
|
711.2
|
693
|
4473
|
|
24.0 x
36.0
|
36.0
|
914.4
|
24.0
|
609.6
|
40.0
|
1016.0
|
28.0
|
711.2
|
834
|
5382
|
|
24.0 x
44.0
|
44.0
|
1117.6
|
24.0
|
609.6
|
48.0
|
1219.2
|
28.0
|
711.2
|
1022
|
6595
|
|
24.0 x
48.0
|
48.0
|
1219.2
|
24.0
|
609.6
|
52.0
|
1320.8
|
28.0
|
711.2
|
1116
|
7202
|
|
29.0 x
59.0
|
59.0
|
1498.6
|
29.0
|
736.6
|
63.0
|
1600.2
|
33.0
|
838.2
|
1667
|
10756
|
|
30.0 x
36.0
|
36.0
|
914.4
|
30.0
|
762.0
|
40.0
|
1016.0
|
34.0
|
863.6
|
1047
|
6756
|
|
30.0 x
48.0
|
48.0
|
1219.2
|
30.0
|
762.0
|
52.0
|
1320.8
|
34.0
|
863.6
|
1401
|
9040
|
|
32.5 x
65.0
|
65.0
|
1651.0
|
32.5
|
825.5
|
69.0
|
1752.6
|
36.5
|
927.1
|
2064
|
13316
|
|
36.0 x
36.0
|
36.0
|
914.4
|
36.0
|
914.4
|
40.0
|
1016.0
|
40.0
|
1016.0
|
1260
|
8131
|
|
44.5 x
44.5
|
44.5
|
1130.3
|
44.5
|
1130.3
|
48.5
|
1231.9
|
48.5
|
1231.9
|
1936
|
12490
|
|
44.5 x
68.0
|
68.0
|
1727.2
|
44.5
|
1130.3
|
72.0
|
1828.8
|
48.5
|
1231.9
|
2970
|
19161
|
ROUND VSP AND VSE VENT
DIMENSIONS
Nominal
Size |
A |
B |
Bolt Hole
Design |
Net
Relief |
Outside
Dimension |
Inside
Dimension |
Bolt
Circle |
No. of
Holes |
Hole
Dia. |
in. |
mm. |
in. |
mm. |
in. |
mm. |
in. |
mm. |
in. |
mm. |
in.
sq. |
cm.
sq. |
8.0 |
200.0 |
13.50 |
342.90 |
8.00 |
203.20 |
11.750 |
298.45 |
8 |
0.875 |
22.23 |
44 |
284 |
10.0 |
250.0 |
16.00 |
406.40 |
10.00 |
254.00 |
14.250 |
361.95 |
12 |
1.000 |
25.40 |
71 |
458 |
12.0 |
300.0 |
19.00 |
482.60 |
12.00 |
304.80 |
17.000 |
431.80 |
12 |
1.000 |
25.40 |
104 |
671 |
14.0 |
350.0 |
21.00 |
533.40 |
13.25 |
336.55 |
18.750 |
476.25 |
12 |
1.125 |
28.58 |
130 |
839 |
16.0 |
400.0 |
19.75 |
501.65 |
16.25 |
412.75 |
18.125 |
460.38 |
16 |
0.500 |
12.70 |
195 |
1258 |
18.0 |
450.0 |
21.75 |
552.45 |
18.25 |
463.55 |
20.125 |
511.18 |
16 |
0.500 |
12.70 |
247 |
1594 |
20.0 |
500.0 |
23.75 |
603.25 |
20.25 |
514.35 |
22.125 |
561.98 |
20 |
0.500 |
12.70 |
306 |
1974 |
24.0 |
600.0 |
27.75 |
704.85 |
24.25 |
615.95 |
26.125 |
663.58 |
20 |
0.625 |
15.88 |
443 |
2858 |
30.0 |
750.0 |
33.75 |
857.25 |
30.25 |
768.35 |
32.500 |
825.50 |
28 |
0.625 |
15.88 |
695 |
4484 |
32.0 |
800.0 |
35.75 |
908.05 |
32.25 |
819.15 |
34.500 |
876.30 |
28 |
0.625 |
15.88 |
792 |
5110 |
36.0 |
900.0 |
39.75 |
1009.65 |
36.25 |
920.75 |
38.500 |
977.90 |
32 |
0.625 |
15.88 |
1004 |
6477 |
40.0 |
1000.0 |
43.75 |
1111.25 |
40.25 |
1022.35 |
42.500 |
1079.50 |
36 |
0.625 |
15.88 |
1241 |
8006 |
44.0 |
1100.0 |
47.75 |
1212.85 |
44.25 |
1123.95 |
46.500 |
1181.10 |
40 |
0.625 |
15.88 |
1503 |
9697 |
Type EXP/DV
Type EXP/DV Vent
is a round domed vent of composite construction laser cut in a stitch
pattern in the done area. An FEP/PTFE liner covers the slits providing a
seal. The vent burst pressure is controlled by the arrangement of the
stitch pattern.
Burst Pressure
(pstat)From 1 psig (0.07
barg) and above depending on size.Sizes: 6" (150
mm) to 48" ( 1200 mm) relief diameter.Vacuum
ServiceThe EXP/DV vent
is fitted with a vacuum support to resist high vacuum.
Service
CapabilitiesThe type EXP/DV
vent exhibits good performance under pressure cycling conditions from
vacuum to light positive pressure.
Burst
ToleranceThe Burst
Tolerance is +/- 0.5 psig (0.034 barg) of the nominal burst pressure. A
tag is fixed to the discharge side of the vent and marked with the burst
pressure range. Example: A vent with a nominal burst pressure of 3 psig
(0.21 barg) will be tagged minimum 2.5 psig ( 0.17 barg) - maximum 3.5
psig (0.24 barg).
MaterialsThe top or burst
control section and the vacuum support are 316SS. The seat is Teflon.
Other top section and seal materials are available.
Operating
PressureThe EXP/DV vents
are suitable for positive operating pressures up to 80% of the minimum
burst pressure. Example: A vent with a nominal burst pressure of 2.5 psig
(0.17 barg) is suitable for operating pressure up to 2 psig ( 0.138
barg).
InstallationThe EXP/DV vent
can be installed between standard weldneck flanges in accordance with DIN
PN 10, ANSI 150 or directly on to the structure to be protected. The vent
must always be installed with a hold-down ring on the outer side to ensure
proper performance. The vents are supplied with gaskets ready for
installation.
Operating
Temperature-40°F (-40°C) to
500°F (260°C)Thermally
insulated vents using ceramic fiber material may be offered to prevent
heat loss or condensation on the vent or to permit their use in high
temperature service up to 2000°F (1093°C).
Type LCV
The EXP/LCV vent
is a rectangular flat vent of composite construction laser cut in a stitch
pattern around the vent’s perimeter.
Vacuum
Service
The LCV vent is
fitted with a support to resist vacuum.
Burst Pressure
(pstat)
0.5 psig (0.035
barg) to 5 psig (0.35 barg), depending on size, and in the same sizes as
types VSP and VSE vents.
Service
Capabilities
The type EXP/LCV
vent is designed for static or light pressure cycling duty.
Burst
Tolerance
The Burst
Tolerance is +/-0.25 psig (0.017 barg) of the nominal burst pressure. Tags
are marked with a min/max burst range.
Materials
The top section
is 316SS with a Teflon seal. Other top section materials are
available.
Operating
Pressure
The vents are
suitable for operating pressures up to 60% of the minimum burst
range.
Installation
The type EXP/LCV
vent is supplied with gaskets ready for installing in Safety
Frames
For technical
assistance on any explosion vent contact BS&B Safety Systems,
Inc.
Teflon is
generally used other appropriate fluorocarbons may be supplied.
Teflon is registered trademark of DuPont. |
ENG
DE
RUS
FR
ITA
