LMS Garratt

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An unidentified garratt near Ampthill Tunnel north portal, 1954 with a Toton-Brent coal train for which it was designed. Note the Midland milepost in the foreground.

The London Midland and Scottish Railway (LMS) Garratt was a class of Garratt 2-6-0+0-6-2 steam locomotive designed for heavy freight. 33 were built from 1927, making them the most numerous class of Garratt in Britain.

[edit] Overview

The LMS had been following the Midland Railway's "small engine policy" that led to most of the Toton (Nottinghamshire)-Brent (London) coal trains being double-headed by 0-6-0 locomotives. The LNER had introduced a solitary U1 2-8-0+0-8-2 Garratt in 1925 for banking work. It was realised that double heading was uneconomical so a double locomotive was ordered from Beyer Peacock. However, Derby insisted on fitting their standard axle boxes which frequently overheated on the LMS Class 4F 0-6-0 to the design and this was their principal weakness, resulting in the design not being successful. They were always heavy on coal and maintenance.

3 locomotives were built in April 1927 and the remaining 30 were built August – November 1930. All were built with straight sided bunkers but from 1931 the 1930 locomotives and the last of the 1927 trio were fitted with revolving coal bunkers. These were conical in shape and were revolved or oscillated by means of a small 2-cylinder steam engine. The revolving bunkers prevented coal dust from entering the cab and the oscillation facility made them self-trimming.

Originally number 4967-4999 the numbering was unusual in that the 1930 builds preceded those of 1927. They were later renumbered 7967-7999 in the same order to make way for the new Black 5’s . British Railways added 40000 to their numbers.

The roundhouses at Toton MPD had to have extra length Garratt roads to accommodate them. Mostly used for heavy coal trains, they later found other uses as well. Others were allocated to Wellingborough and Hasland near Chesterfield. Trains for Manchester were generally routed along the Hope Valley Line. A few would work the route from Pye Bridge, near Ironville, through Ambergate, but only as far Rowsley, where the train would be split. This was normal for goods trains because of the danger of couplings breaking on the climb to Peak Forest. Also, although they had ample tractive effort to climb the gradient, in the days before goods wagons were braked, there were problems on the way down into Chinley. On an early attempt, the loco was inspected at Heaton Mersey and it was found that all of its brake blocks had melted.

The class was withdrawn between June 1955 and April 1958 None has survived into preservation.

[edit] Technical

Power Classification: Not classified

Introduced: 1927-1930

Designer: Sir Henry Fowler & Beyer Peacock.

Weights:
Loco - 148t 15cwt (Fixed Bunker), 155t 10cwt (Rotary Bunker).

Driving Wheel: 5' 3"

Boiler pressure: 190psi superheated

Cylinders (4): 16 ½ " x 26" (Outside)

Tractive Effort: 45,620lbf

Valve Gear: Walschaert (piston valves)

[edit] Photo Links

• [[1]]

• [[2]]

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• [[4]]

[edit] References

• Bob Essery & G. Toms (1998) LMS & LNER Garratts Wild Swan ISBN 0-906867-93-2
• Pixton, B., (2000) North Midland: Portrait of a Famous Route, Cheltenham: Runpast Publishing
• Bentley, C., (1997) British Railways Operating History: Volume one, The Peak District, Carnarvon: XPress Publishing.
• Hugh Longworth British Railway Steam Locomotives 1948-1968 - OPC - ISBN 0-86093-593-0

[edit] External links

• photo of Garratt at Peterborough