The superheater used with Lancashire boiler is shown in Fig. 3.2. The arrows show the path of the gases, when the superheater is in commission.
When superheated steam is to be produced, the dampers are closed and opened so that the flue gases pass on to the superheater flue at the back and travel towards the bottom flue. In this case, valve 2 is closed and valves 3 and 4 are opened so that steam from the shell passes to the superheater and after getting superheated, they are passed to the main pipe 1. If the superheated steam is not required, valve 2 is opened and valves 3 and 4 are closed and the damper to the superheater flue is closed and the other damper is opened, thus bypassing the superheater and steam is passed through valve 2 to main pipe 1.
Leave a Reply