Friday 19 April 2013

Crewe South Junction (1940) Signal Box

Crewe South Junction Signal Box was taken out of use in 1985 but survives in a semi-derelict form.

Crewe South Junction Signal Box controlled movements at the south end of Crewe Station from 1940 to 1985. The structure of the signal box survives in a semi-derelict form. This 'ARP' box, with a Westinghouse Style 'L' Power Frame, is the last-but-one in a series of signal boxes which have controlled the important junctions at the south end of Crewe Station.

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 and Crewe South Junction signal boxes were rebuilt, replacing the earlier 1907 signal boxes which used the 'Crewe' All Electric System. New point machines were provided and the electrically-operated semaphore signals were replaced by colour light 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 South Junction (together with a second for Crewe North Junction and a third 'Standby' frame) was placed in March 1939.

The Crewe South Junction lever frame order called for 227 levers made up of 72 point levers, 127 signal levers, 8 'special' levers, 7 spare levers and 13 spare spaces. These levers were supplied as 19 off 12-way sections which were mounted in-line to form one large frame.

 
Detail showing miniature levers (picture shows a similar Style 'L' frame at Crewe North Junction. 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 provided the electrical interlocking were mounted on steel shelves in a large Relay Room on the ground floor. 'Shelf' relays were used, interwired on site.

When I was young, I thought it a curious-looking box but, for me, it didn't quite have the air of mystery which Crewe North Junction possessed. I went inside Crewe South Junction once in the 1970s when my firm had started supplying telecommunication equipment to the railways but, sadly, I didn't take any pictures.

The Crewe North Junction (1940) Signal Box is briefly described here

In 1985 control of the Crewe area was transferred to Crewe Signalling Centre, built on part of the site of the famous Crewe North Shed.

References

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

External Links

Crewe South Junction by Mark Adlington.

My Pictures

Crewe Area.