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In-Line Detonation Flame Arrester with shut-off valve, for stable detonations and deflagrations in a straight through design, unidirectional

  • protects against stabilized burning
  • no expensive emergency switch-offs are required
  • temperature monitoring is not necessary
  • minimum number of FLAMEFILTER® discs
  • easy to maintain
  • the individual FLAMEFILTER® discs can be quickly removed and installed
  • the FLAMEFILTER® discs can be individually replaced
  • provides protection from defl agrations and stable detonations
  • ideal protective system for vacuum pumps
  • cost efficient spare parts

Function and Description

The PROTEGO® DR/SV flame arrester series ideally combines the function of a detonation arrester with the advantages of a shut-off valve. In case of ignition, the fire can be stabilized within the flame arrester when the flammable gas continues to flow. Inside the detonation arrester, is a valve (1) that closes in case of fire, stops the additional supply of fuel and extinguishes the flames. Temperature sensors in combination with an emergency switch off do not have to be installed if the type PROTEGO® DR/SV device is used. This device is particularly useful for the sucction-side protection of compressors and pumps.

The flame arrester protects against deflagrations and stable detonations. It can be installed anywhere in the pipe independently from the distance of the potential ignition source.

Once a detonation enters the flame arrester, energy is absorbed from the detonation shock wave by the central plate disc (2) before the flame is extinguished in the narrow gaps of the two FLAMEFILTER® discs (3). This device can be used for fluids of explosion group IIA (NEC group D).

The in-line detonation flame arresters are unidirectional and equipped with a threaded connection. The thread can be executed to international standards. The standard design can be used up to an operating temperature of +60°C / 140°F and an (absolute) operating pressure up to 1.1 bar / 15,9 psi.

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 chart on the following page

DNG ½"G ¾"
a115 / 4.53115 / 4.53
b100 / 3.94100 / 3.94
Dimensions in mm / inches

Material selection for housing

Design A B
HousingBrassStainless Steel
GasketWS 3822WS 3822
Flame arrester unitAA, B
Special materials upon request

Material combinations of flame arrester unit

FLAMEFILTER®*Stainless SteelStainless Steel
SpacerStainless SteelStainless Steel
Support for FLAMEFILTER®BrassStainless Steel
WasherBrassStainless Steel
* the FLAMEFILTER® are also available in the materials Tantalum, Inconel, Copper, etc. when the listed housing and cage materials are used. Special materials upon request

Selection of explosion group

MESGExpl. Gr. (IEC / CEN)Gas Group (NEC)
> 0,90 mmIIAD
Special approvals upon request

Selection of max. operating pressure

DNG ½"G ¾"
Pmax1,1 / 15.91,1 / 15.9
Pmax = Maximum allowable operating pressure in bar / psi absolut, higher operating pressure upon request

Specification of max. operating temperature

≤ 60°C / 140°FTmaximum allowable operating temperature in °C
higher operating temperatures upon request

Type of connection

Pipe thread DIN ISO 228-1DIN
other types of thread 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”.