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

Skilful operation of Hoffman kiln

Skilful operation of Hoffman kiln

It is clear that a Hoffmann kiln required a skilful and careful operation. If the temperaturewas too high, the bricks would come out

misshapen. If the temperature was too low, the bricks would be weak and porous. If the bricks were heated up or cooled down too fast,

 this would result in cracked, warped or twisted goods. The man in charge of the kiln ascertained the completion of the burning by means

of trials,shrinkage measurements and Seger cones (picture on the right). In a well operated Hoffmann kiln, on average only 3 percent of

bricks were spoiled, but with inferior management this could be 50 percent.