Clay brick making machine-Brick machine-Baoshen brick making machine

Description of Hoffman kiln technology

The kiln investigated at Stewartby is a natural draught multi-chamber transverse-arch Hoffmann Kiln designed for producing Fletton bricks in a continuous process. The Kiln is a large permanent structure built entirely from ordinary building brick,  inside and out, with a number of simple cast iron and steel non-structural components.  The Kiln consists of a central chimney, approximately 70m (200ft) high, connected to a main flue running the length of the Kiln. On either side of the main flue there are seventeen barrel-arched firing chambers, each linked to the main flue via damper controlled underfloor ‘steam-flues’ (see figure 1 in Annex)

The chambers are connected via a number of small tunnels, known as fire trace holes, through the dividing walls just above ground level. A number of offtake flues in the chamber walls carry drying and combustion gases down into the ‘steam-flues’, which are under draught as soon as the damper controls to the main flue are lifted. Each chamber is also connected to a hot air flue, situated around the top of the kiln, which enables hot air, via damper controls, to be recirculated from one chamber to another. Support fuel can be added to each chamber through small openings in the roof. Larger openings allow the control of temperature (reduction) by introducing ingress air.