Thursday 10 January 2013

Crewe North Junction (1940) Signal Box

A modern view of Crewe North Junction Signal Box, still in situ but now forming part of Crewe Heritage Centre and overshadowed by the overhead electrification structures.

Crewe North Junction Signal Box controlled movements at the North end of Crewe Station from 1940 to 1985. The signal box has been preserved in situ and now forms a major exhibit at Crewe Heritage Centre. This 'ARP' box, with two large Westinghouse Style 'L' Power Frames, is the last-but-one in a series of signal boxes which have controlled the important junctions at the north end of Crewe Station. There's a very brief history of these signal boxes here.

In 1938, with the threat of war and aerial attack looming, it was decided that certain strategic signal boxes should be replaced by an 'ARP' ('Air Raid Precautions') design, better able to withstand blast damage. Accordingly, Crewe North Junction signal box was rebuilt, replacing the earlier 1907 signal box which used the 'Crewe' All Electric System with electric operation of points and semaphore signals.

Westinghouse Brake and Signal Company had been supplying the Style 'L' miniature lever frame since 1929 so it was a 'safe' choice. The L.M.S. order for Crewe North Junction (together with a second for Crewe South Junction and a third 'Standby' frame) was placed in March 1939. The following month, further orders were placed for two more Style 'L' frames for the resignalling of Preston. The Preston project never went ahead and the equipment ended up being used at Euston after the Second World War! Finally, a further frame was ordered for Liverpool Lime Street in January 1940.

The Crewe North Junction lever frame order called for 214 levers made up of 65 point levers, 120 signal levers, 7 'special' levers, 12 spare levers and 10 spare spaces. These levers were divided between two lever frames mounted back-to-back, with a walkway in between to allow maintenance, on the first floor of of the building (the 'operating floor'). A series of windows allowed the signalmen to actually observe the trains they were controlling.

Detail showing miniature levers. White are spare, Red are signals, Black are points. The lamps on the almost vertical panel behind the levers are repeaters.

Movement of each lever drives a vertical shaft via bevel gears. The vertical shaft carries the electrical contacts used for control and interlocking.

With covers removed, the bevel gears which drive the vertical 'drum' of contacts can be seen.

The associated relays which provide the electrical interlocking are mounted on steel shelves in a large Relay Room on the ground floor. 'Shelf' relays are used, interwired on site.

One aisle in the large Relay Room. Shelf-type relays (inter-wired on site) fill the metal shelving.

Looking at Crewe North Junction box from the platforms when I was young, I thought it looked mysterious, with its unfamilar architecture sitting out-of-reach across the maze of trackwork. Finally, I got to visit the box in the 1970s two or three times when my firm had started supplying telecommunication equipment to the railways.

In 1985 control of the Crewe area was transferred to an industrial building painted red and white looking more like a fugitive 'B&Q' than a Signalling Centre. I feared for the future of the redundant 1940 Crewe North Junction signal box but, remarkably, it has survived as part of Crewe Heritage Centre.

In December 2008, I returned to Crewe North Junction box, which is looked after by a group of ex-railwaymen and enthusiasts and I was invited to 'signal' a few moves on the Style 'L' Power Frame.

References

'The Style L Power Frame' written and published by J. D. Francis 1989 (ISBN 0 9514636 0 8).

External Links

Crewe North Junction signal Box (Wikipedia).
Crewe North Junction by Mark Adlington.

My Pictures

Crewe North Junction Signal Box.
Crewe Area.