The DUALFLAME MC (Manual Control) burners are equipped with special dimensioned burner nozzles according to the existing gas consumption, available flame length and distance between the burner lances. This choice of tailor-made burner nozzles forms the basis for an optimised burner lance.

The DUALFLAME MC burner is also available as a SPB sideport burner. This burner is shorter and especially designed for use between the burner ports in a system with side-port firing.

The burner can be further adjusted with the hand wheels at the rear part of the burner lance during operation.

Adjusting the position of the interior nozzle will amend the annular gap towards the outside nozzle. In case the interior nozzle is drawn back, the kinetic energy of the gas will be reduced and consequently the mixing impulse of both the inner and outer gas streams will be reduced, thus producing a wide and soft flame. On the other hand a sharp and strong flame can be achieved by reducing the annular gap of inner and outer nozzles when moving the inner nozzles forward.

The length of the flame can be determined exactly with the second hand wheel at the burner, whereby the gas quantity in the interior and exterior nozzle can be controlled. Maintaining the entire gas quantity needed in the interior nozzle will create high gas velocity and thus a very long flame. Distributing the gas quantity to both the inner and outer nozzle will reduce the flame length.

Normally the gas quantity in the interior nozzle is adjusted by moving the outside nozzle valve when total gas quantity is constant:

• By closing the outer nozzle valve the gas quantity in the inner nozzle increases
• By opening the outer nozzle valve the gas quantity in the inner nozzle decreases

The adjustable gas velocity can vary e.g. between values of > 20 m/s and < 200 m/s.