Howden-Johnson boiler

Howden-Johnson marine boiler


Howden-Johnson marine steam boiler drawing
The Howden-Johnson boiler tried to improve the poor water circulation in the common Scotch fire-tube boilers by adding water tubes in a dry-back combustion chamber. It was claimed that this modification made the Howden-Johnson boilers 10 per cent more efficient than conventional Scotch fire-tube marine boilers. The Howden-Johnson boilers as well as the Prud'Hon Capus boiler failed to make an impact despite of these advantages, the disadvantages of the hybrid arrangement being greater than the advantages.
The operation pressure was 15 bar and the steam was superheated to 307°C.

Howden-Johnson marine steam boiler

The red coil, between the convection water-tubes and the smoke tubes, is the superheater.

The Howden-Johnson marine steam boiler without the common dry-back combustion chamber mounted.
Part of the superheater is visible above the convection water-tubes