British Railways Standard Class 9F

BR standard class 9F

The British Railways BR Standard Class 9F 2-10-0 is a class of steam locomotive designed for British Railways by Robert Riddles. The Class 9F was the last in a series of standardised locomotive classes designed for British Railways during the 1950s, and was intended for use on fast, heavy freight...

 steam locomotives Nos 92020-9 were experimentally built with Franco-Crosti boiler

Franco-Crosti boiler

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 , the Italian state railway.- Purpose :...

s, thus forming a subclass. All ten were built in 1955 at Crewe Works

Crewe Works

Crewe railway works is a British railway engineering facility built in 1840 by the Grand Junction Railway. It is located in the town of Crewe, in the county of Cheshire....

.

The Franco-Crosti boiler took the form of a single cylindrical water drum running along the underside of the main boiler barrel; the standard chimney at the front was only used during lighting-up, in normal working the gases went through firetubes inside the preheater drum that led to a second smokebox situated beneath the boiler from which there emerged a chimney on the right-hand side (fireman's), just forward of the firebox.

In the event, the experiment did not deliver the hoped-for benefits, and efficiency was not increased sufficiently to justify the cost and complexity. Moreover, conditions were unpleasant on the footplate in a cross-wind, this in spite the later provision of a small deflector plate forward of the chimney. These problems led to the subsequent sealing off of the preheater drum, over the period 1959-1961, and the locomotives were then worked conventionally. As a result of this, there was a reduced ability to generate steam, and so their power classification was reduced from 9F to 8F.

All were fitted with the BR1B-type 4275 gallons (19,434.5 l) tender.

Stock list

No.	Built	Converted to conventional	Withdrawn
92020	March 1955	1961	November 1967
92021	March 1955	1960	November 1967
92022	March 1955	1962	November 1967
92023	March 1955	1961	November 1967
92024	June 1955	1960	November 1967
92025	June 1955	1960	November 1967
92026	June 1955	1959	November 1967
92027	July 1955	1960	August 1967
92028	July 1955	1959	October 1966
92029	July 1955	1960	November 1967

Withdrawal

No. 92028 was the first Franco-Crosti 9F to be withdrawn in October 1966, with 92027 following in August 1967, but the remainder were withdrawn en masse in November 1967. All were scrapped.

Year	No. Withdrawn	Nos
1966	1	92028
1967	9	92020–7/9

Further reading

• Richard Derry The Book of the 9F 2-10-0s ISBN 1903266734
• Gavin Morrison The Power of the 9Fs OPC Railprint 2001 ISBN 0860935582
• H.C.B. Rogers, Riddles and the 9Fs (Ian Allan, 1982)