Steam Jet Draught in Boilers

Steam Jet Draught refers to the Draught created by using a jet of steam.  The steam generated by the boiler can be used for this purpose.  The jet of steam is used to create an airflow which will cause the flue gases to exit through the chimney.

If the steam jet is applied near the stack of the chimney, the negative pressure it creates draws the flue gases from the furnace into the Chimney.  This is known as induced draught.

If the jet is applied below the grate, the steam pushes the flue gases in the direction of the chimney.  This is a forced draught.

The Steam Jet draught is a simple mechanism.  No external equipment such as compressors or blowers are required.  The steam when used below the grate cools the firebars and prevents the clinkers from sticking to the bars.