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Pressure/Vacuum Relief Valve deflagration- and endurance burning-proof

  • selecting set pressure close to relieving pressure results in product loss reduction
  • more design flexibility through higher reseating pressures; vents reseat when conventional vent is still discharging costly product or nitrogen
  • the valve disc is guided within the housing to protect against harsh weather conditions
  • high performance seal reducing product loss below EPA‘s 500ppm rule preventing environmental pollution
  • can be used as protective system according to ATEX in areas subject to explosion hazards
  • safe against deflagration and endurance burning of alcohol/air mixtures and substances of explosion group IIB3
  • high flow capacity through large flame filter cross-section, results in low pressure drop
  • FLAMEFILTER® provides protection against atmospheric deflagration and endurance burning
  • FLAMEFILTER® integrated into the valve saves space, weight and reduces cost
  • FLAMEFILTER® protected from clogging caused by product vapours
  • flame transmission proof condensate drain
  • maintenance friendly design
  • modular design enables individual FLAMEFILTER® and valve pallets to be replaced
  • special design with lifting gear can be purchased

Function and Description

The deflagration-proof and endurance burning-proof PV/EBR-E type PROTEGO® valve is a highly developed combined pressure/ vacuum relief valve for high fl ow capacities with an integrated flame arrester that is specially used for applications handling ethanol. It is primarily used as a device for flame transmission proof outbreathing on tanks, containers and process engineering apparatus. The valve offers reliable protection against excess pressure and vacuum, prevents the inbreathing of air and product losses almost up to the set pressure and also protects against atmospheric defl agration as well as endurance burning if stabilized burning occurs. The PROTEGO® flame arrester unit is designed to achieve minimum pressure drop with maximum safety. The PROTEGO® PV/EBR-E valve is available for substances of explosion group IIB3 (MESG ≥ 0,65 mm) and provides specific protection against defl agration and endurance burning of alcohol/air mixtures (such as ethanol/air).

The valve functions proportional, so the set pressures should be selected in relation to the proportional behaviour (such as a 10%, 40%, or 100% overpressure from the set pressure to the relieving pressure at which the required flow performance is reached).

The tank pressure is maintained up to the set pressure with a tightness that is far superior to the conventional standard due to our state of the art manufacturing technology. This feature is ensured by the valve seats made of high quality stainless steel and with individually lapped valve pallets (1) or with an air cushion seal (2) in conjunction with high quality FEP diaphragm. The valve pallets are also available with a PTFE seal to prevent the valve pallets from sticking when sticky products are used and to enable the use corrosive fluids. After the excess pressure is discharged, the valve reseats and provides a tight seal.

If the set pressure is exceeded, explosive gas/product-vapour air mixtures are released to the atmosphere. If this mixture ignites, the integrated PROTEGO® flame arrester unit (3) prevents flame transmission into the tank. If additional mixture continues to flow and stabilized burning occurs, the integrated flame arrester unit prevents flashback as a result from endurance burning. The valve is protected and also fulfils its function under this severe service conditions. The spring loaded weather hood opens as soon as the fusible element (4) melts.

The valve can be used up to an operating temperature of +60°C / 140°F and meets the requirements of European tank design standard EN 14015 – Appendix L and ISO 28300 (API 2000).

Type-approved in accordance with the current ATEX Directive and EN ISO 16852 as well as other international standards.


To select the nominal size (DN), please use the flow capacity charts on the following pages

DN 80 / 3" 80 / 3" 100 / 4" 100 / 4"
Set pressure≤ +35 mbar> +35 mbar≤ +35 mbar> +35 mbar
Set pressure≤ +14 inch W.C.> +14 inch W.C.≤ +14 inch W.C.> +14 inch W.C.
a345 / 13.58475 / 18.70345 / 13.58475 / 18.70
b141 / 5.55141 / 5.55141 / 5.55141 / 5.55
c218 / 8.58218 / 8.58218 / 8.58218 / 8.58
d353 / 13.90353 / 13.90353 / 13.90353 / 13.90
Dimensions in mm / inches Dimensions for pressure/ vacuum relief valve with heating jacket upon request

Material selection for housing

Design BC
HousingSteelStainless Steel
Heating jacket (PV / EBR-E-H-...)SteelStainless Steel
Valve seatStainless SteelStainless Steel
Weather hoodSteelStainless Steel
Special materials upon request

Material combinations of flame arrester unit

Design A
FLAMEFILTER® cageStainless Steel
FLAMEFILTER®Stainless Steel
SpacerStainless Steel
Special materials upon request

Material selection for pressure valve pallet

Design ABCD
Pressure range [mbar]
[inch W.C.]
+2.0 up to +3.5
+0.8 up to +1.4
>+3.5 up to +14
>+1.4 up to +5.6
>+14 up to +210
>+5.6 up to +84
>+35 up to +210
>+14 up to +84
Valve palletAluminiumStainless SteelStainless SteelStainless Steel
SealingFEPFEPMetal to MetalPTFE
Special material as well as higher set pressure upon request

Material selection for vacuum valve pallet

Design ABCD
Vacuum range [mbar]
[inch W.C.]
-3.5 up to -5.0
-1.4 up to -2.0
<-5.0 up to -14
<-2.0 up to -5.6
<-14 up to -50
<-5.6 up to -20
<-14 up to -50
<-5.6 up to -20
Valve palletAluminiumStainless SteelStainless SteelStainless Steel
SealingFEPFEPMetal to MetalPTFE
Special material as well as higher set vacuum upon request

Selection of explosion group

MESGExpl. Gr. (IEC / CEN)Gas Group (NEC)
≥ 0,65 mmIIB3C
Special approvals upon request

Flange connection type

EN 1092-1; Form B1
ASME B16.5 CL 150 R.F.
other types upon request

Design Types and Specifications

Almost any combination of vacuum and pressure levels can be set for the valve. The valve discs are weight loaded. When the difference between the pressure and vacuum exceeds 150 mbar / 60.2 inch W.C., special valve discs are used.
There are two different designs:

Pressure/vacuum relief valve, basic design


Pressure/vacuum relief valve with heating jacket (max. heating fluid temperature +85°C / 185°F)


Additional special devices available upon request


Pressure: +2.0 mbar +210 mbar
+0.8 inch W.C. +84 inch W.C.
Vacuum: -14 mbar -50 mbar
-5.6 inch W.C. -20 inch W.C.
Vacuum: -3.5 mbar -14 mbar
-1.4 inch W.C. -5.6 inch W.C.
for presssure up to max. + 150 mbar / 60.2 inch W.C.
Higher and lower settings upon request

Flow Capacity Chart

The flow capacity charts have been determined with a calibrated and TÜV certified flow capacity test rig. Volume flow V in (m³/h) and CFH refer to the standard reference conditions of air ISO 6358 (20°C, 1bar). For conversion to other densities and temperatures refer to Sec. 1: “Technical Fundamentals”.