LMS Route: Nuneaton to Birmingham New Street

LMS Route: Birmingham New Street to Tamworth

Saltley Shed: mrsalt1212, mrsalt1211, mrsalt1268 and mrsalt1269

British Railways Standard Class Crosti-boilered 9F 2-10-0 No 92029 is wreathed in steam as it prepares to depart the roundhouse. In the view seen below the driver carefully draws the locomotive forward needing to ensure the locomotive is balanced on the turntable. Failure to do so would result in making it very difficult for the locomotive to be turned. Built at Crewe works in July 1955 No 92029 was the last of ten locomotives built with the experimental Franco-Crosti boiler, which was decommissioned in August 1960 when the pre-heater was sealed off, and remained in service until November 1967 when it was withdrawn from 8H Birkenhead shed. The Franco-Crosti boiler is a type of boiler used for steam locomotives. It was designed in the 1930s by Attilio Franco and Dr Piero Crosti, two engineers working for the Ferrovie dello Stato (FS), the Italian state railway. The Franco-Crosti boiler is a modification of the conventional fire tube boiler design used on most steam locomotives. Unlike conventional boilers the heat remaining in the exhaust gases is used to preheat the water supply for the main boiler using a secondary heat exchange mechanism. This mechanism, known as the feedwater heater is essentially a secondary boiler.

The preheated feedwater is fed at full boiler pressure into the main boiler via clack valves. The feedwater heater is not designed to produce steam, instead raising the temperature of the feedwater. This allows the heater to utilize the remaining energy in the exhaust gases effectively. The typical configuration of a Franco-Crosti boiler had a relatively conventional main boiler with one or two secondary feedwater heaters running parallel to the boiler barrel. Where the loading gauge did not allow the feedwater heater to be placed beside the boiler it was mounted beneath. When the locomotive is started, cold water is fed directly into the main boiler which operates normally with the exhaust gases flowing out of the main chimney via the smokebox. Once the boiler is producing steam, the exit from the smokebox into the main chimney is closed and the exhaust gases instead flow through the feedwater heater and exit via the secondary chimney located towards the rear of the locomotive. Water fed into the boiler is now pre-heated in the feedwater heater and enters the boiler at higher than normal temperature and pressure.

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The two following views show the locomotive on another occasion but not in steam.

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