EN 746-2

Here you will find extracts from and explanations of EN 746-2. This part of the EN 746 series of standards defines, together with EN 746-1, the safety requirements for burners and fuel handling systems that are part of industrial thermoprocessing equipment (IThE).

Contents

5.1 General

5.2 Gaseous fuels
5.2.1 Gas pipework
5.2.1.1 General
5.2.1.2 Connections
5.2.1.3 Unconnected pipework
5.2.1.4 Galvanic cells
5.2.1.5 Flexible tubing and couplings
5.2.1.6 Marking
5.2.1.7 Soundness
5.2.1.8 Condensate drains
5.2.1.9 Purge points
5.2.1.10 Blow-off and breather pipes or conduits
5.2.1.11 Pressure relief devices and flame arrestors on pipework
5.2.1.12 Pressure oscillations
5.2.1.13 Equipment supplied with different fuel gases
5.2.1.14 By-pass
5.2.1.15 Isolation of required safety devices

5.2.2 Required safety devices
5.2.2.1 Manual isolating valve
5.2.2.2 Filter/strainer
5.2.2.3 Automatic shut-off valves
5.2.2.3.1 General
5.2.2.3.2 Single burner equipment
5.2.2.3.3 Multiple burner equipment
5.2.2.3.4 Valve proving system
5.2.2.4 Gas pressure regulator
5.2.2.5 Air and gas flow and pressure detectors
5.2.2.5.1 Air
5.2.2.5.2 Gas
5.2.2.5.2.1 Low gas protection
5.2.2.5.2.2 High gas protection
5.2.2.6 Flue gas venting
5.2.2.7 Ignition system
5.2.2.8 Individual manual shut-off valves for burners

5.2.3 Combustion air and pre-purging the combustion chamber and flue passages
5.2.3.1 Combustion air system
5.2.3.2 Pre-purging of the combustion chamber
5.2.3.3 Air/gas fuel ratio

5.2.4 Supply of pre-mixed fuel gas/air
5.2.4.1 Mixture pipework
5.2.4.2 Air and gas supply to the mixture circuit

5.2.5 Burners
5.2.5.1 Main burners
5.2.5.2 Radiant tube burner system
5.2.5.3 Start-up and ignition
5.2.5.3.1 Start-up
5.2.5.3.2 Start fuel flow rate
5.2.5.3.3 Ignition
5.2.5.3.4 Safety time
5.2.5.3.5 Flame failure
5.2.5.4 Burner capacity control
5.2.5.5 Permanent pilots

5.2.6 Automatic burner control systems
5.2.6.1 General
5.2.6.2 Low temperature equipment
5.2.6.3 High temperature equipment
5.2.6.4 Automatic burner control systems for burners operating in the open air

Note

The following chapters are printed with the permission of the DIN Deutsches Institut für Normung e.V. (German Institute for Standardization). For the implementation of the DIN Standard, the version with the most recent issue date is deemed authoritative. This is available from Beuth Verlag GmbH, Burggrafenstrasse 6, 10787 Berlin, Germany.