Cochran Boiler: It is a type of vertical multi-tubular boiler and has a number of horizontal fire tubes.
Cochran boiler consists of a cylindrical shell with a dome shaped top where the space provided for steam. Its crown has a hemispherical shape and thus provides maximum volume of space. Its furnace is seamless; below it there is a grate and ash pit. It has a combustion chamber and smoke box, which are connected through fire tubes. Smoke box is connected to chimney. Various mountings are also fitted on it like
(i) Water level indicator (ii) Safety valve
(iii) Steam stops valve (IV) Blow-off cock
(v) Pressure gauge.
Working: The fuel is burnt on the grate inside the furnace. The gases of combustion produced by burning of fuel enter the combustion chamber through the flue tube and strike against the fire brick lining which directs them to pass through number of horizontal tubes, being surrounded by water. After which the gases escape to the atmosphere through smoke box and chimney.
The water surrounded over the fix types get heated and converted into steam. This steams being collected into the crown of boiler. This steam is supplied by steam stop valve.Other Parts of This Question are: