Liverpool Overhead Railway: 1923 Visit to the Works
Note: this is a sub-section of the Liverpool Overhead Railway
1923 Visit to the Works by Institution of Locomotive Engineers
On the afternoon of the 14th June, by the courtesy of Mr. E. J. Neachell, M.I.Mech.E., General Manager, twenty members of the Manchester Centre were enabled to visit the Liverpool Overhead Railway, the object being more particularly the inspection of the daylight signalling system.
The railway, which is over six miles long, was the first elevated railway in the world to be worked electrically, and the second electric railway constructed in this country.
The number of passengers carried annually is now between sixteen and eighteen millions.
The railway, except for short lengths, is entirely of metallic construction. Columns support longitudinal girders, and cross-girders are fixed at regular intervals; these support the railway proper.
The permanent way consists of flat-bottomed rails laid on longitudinal sleepers.
The positive rail conductors are fixed in the six-foot,, and one running rail, and in addition the spare centre rail (formerly used as the. positive rail), are utilised for the return current.
One running rail per track is used for signalling purposes, and the system now installed is of the alternating-current type. Power for it is furnished from the Railway Company’s power-house by two separate sets of motor alternators, each consisting of a direct current motor coupled direct to an alternator of rotating armature type. These were constructed by the Lancashire Dynamo Co, acting as sub-contractors to the Westinghouse Brake and Saxby Signal Co, who installed the new signalling arrangements.
The signalling is arranged on a two-minute service, but actually is based on an interval between trains of 100 seconds. All signals are operated and controlled by means of track circuit.
All the signals are of the “Colour-light” type, in which the condition of the signal is indicated by lights at all times, day and night, which even in bright sunshine can be clearly seen 3,000ft. away.
All the signals are provided with “train-stops,” and the train with trip-valves; special relay valves are provided in conjunction with the latter. They are so arranged that in the event of the train being “tripped,” not only are the brakes applied, but the main circuit breaker on the train is opened and the current cut off from the motor.
These and other interesting points were explained to the visitors, who were conducted over the system in separate parties, afterwards visiting the Company’s own power-house and workshops.
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