The LBSCR I2 class was a class of 4-4-2 steam tank locomotives designed by D. E. Marsh for suburban passenger service on the London, Brighton and South Coast Railway. The I4 class were of the same design but incorporated a superheated boiler.

LB&SCR I2 & I4 classes
Side-view builder's photo of LB&SCR I2 class 4-4-2T.
Type and origin
Power typeSteam
DesignerD.E. Marsh
BuilderBrighton Works
Build date1907-1909
Total producedI2: 10; I4: 5
Specifications
Configuration:
 • Whyte4-4-2T
Gauge4 ft 8+12 in (1,435 mm) standard gauge
Leading dia.3 ft 6 in (1.067 m)
Driver dia.5 ft 6 in (1.676 m)
Trailing dia.4 ft 0 in (1.219 m)
Loco weight68.5 long tons (69.6 t; 76.7 short tons) I2,
70.25 long tons (71.38 t; 78.68 short tons) I4
Fuel typeCoal
Water cap.2,238 imp gal (10,170 L; 2,688 US gal)
Boiler pressure170 psi (12 bar; 1.2 MPa)
CylindersTwo, inside
Cylinder size17.5 in × 26 in (444 mm × 660 mm)
Performance figures
Tractive effortI2: 17,425 lbf (77.51 kN),
I4: 17,790 lbf (79.13 kN)
Career
Retired1933-1940
DispositionAll scrapped

I2 Class

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In 1907, following the failure of his I1 class, Douglas Earle Marsh sought to remedy some of the faults with a new design of 4-4-2T with a longer wheelbase, larger boiler and detailed changes to the front end.[1] In the original order, five of the locomotives would incorporate a superheated boiler, to be supplied by the North British Locomotive Company, and the remainder traditional saturated steam boilers from Brighton Works.[1] In the event, the superheated boilers were delayed in construction and so all ten I2 locomotives had traditional boilers.[1]

I4 Class

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An I4 incorporating a superheated boiler

When the superheated boilers eventually arrived they were used for five further locomotives of the same design as the I2, but these were classified as I4.[1]

Unfortunately neither the I2 nor I4 class addressed the fundamental problems with the I1 class, which was a firebox that was far too small.[2] As a result, the two classes had relatively short lives working lightly loaded secondary services, and the Stroudley D1 class, and Billinton E4 class, which they had been designed to replace, continued working.

Numbering

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LB&SCR numbers were 11-20 and 31-35. The Southern Railway, which acquired the locomotives in 1923, initially numbered them B11-B20, B31-35 and later 2011-2020, 2031-2035.

Withdrawal

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All the I2 were withdrawn between 1933 and 1939[3] but two locomotives, numbers 2013 and 2019, saw further service on the Longmoor Military Railway where they survived until at least 1947. At Longmoor, they were numbered 2400 and 2401 respectively. These numbers were later changed to 72400 and 72401.[4] The I4 class were withdrawn between 1936 and 1940. No examples of either class have been preserved.

Locomotive Summary

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I2 class locomotive fleet summary
LB&SC Number Built S.R. Number Withdrawal Notes
11 December 1907 2011 January 1933 I2
12 March 1908 2012 March 1935 I2
13 April 1908 2013 January 1939 I2, became W.D. 72400 Earl Roberts
14 April 1908 2014 February 1933 I2
15 May 1908 2015 January 1936 I2
16 June 1908 2016 September 1933 I2
17 July 1908 2017 January 1938 I2
18 July 1908 2018 April 1936 I2
19 July 1908 2019 November 1937 I2, became W.D. 72401
20 August 1908 2020 February 1936 I2
31 September 1908 2031 January 1936 I4
32 November 1908 2032 July 1937 I4
33 November 1908 2033 July 1937 I4
34 December 1908 2034 May 1940 I4
35 January 1909 2035 February 1937 I4

References

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  1. ^ a b c d Bradley 1974, p. 81.
  2. ^ Bradley 1974, p. 83.
  3. ^ Bradley 1974, pp. 86–87.
  4. ^ Bradley 1974, p. 87.

Sources

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  • Bradley, D.L. (1974). Locomotives of the London Brighton and South Coast Railway: Part 3. Railway Correspondence and Travel Society.
  • Dendy Marshall, C. F. (1988). History of the Southern Railway. Ian Allan. p. 271. ISBN 0-7110-0059-X.
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