How does an electric locomotive work?
In this fascinating locomotive it is convenient to differentiate the electric part from the mechanical one. The electric part is formed by the circuitry, the motors and the devices which take the electricity. These, in the locomotives fed by overhead cables, have a part in direct contact with the cables and a device which keeps this contact continuously. There are also power switches, devices for accessory services, controls and indicators (voltimeters, manometers). Before arriving to the motors, the electricity taken from the cables goes to the diverse parts of the locomotive through a complex series of devices, remotely controlled by the driver, whose main role is to open or close the circuits as convenient.
The mechanical part is represented by the chassis with the suspension systems and the bodywork, the gearings which transmit the movement from the motors to the wheels, the bearings, the compressed-air brakes, the hand brake, the traction and repulsion systems and other additions of lesser importance. Let us see the elements which transmit the movement to the wheels. The transmission can be done directly by the pertinent speed reducers, or also only by means of connecting rods, or connecting rods and shafts or auxiliary axes. Sometimes, between the motors and the wheels are intercalated some gear wheels, and then the motor is installed in a non-rigid way. In the bodywork or box can be considered three different parts: the first and third one contain control devices and provide a certain space for the personnel in charge of driving; in the center lies the machine itself and the high-voltage devices.
1: Ventilators for cooling the motors - 2: Motion control - 3: Electric conductors for feeding the motors - 4: Hand brake - 5: Cylinders for maneuvering the pantographs - 6: Control of motor connections - 7: Main compressed-air deposit - 8: Electric line - 9: Pantographs - 10: Attachment of the motors to the structure, with suspension springs - 11: Electric motor - 12: Gears connecting driving axes and wheels - 13: Auxiliary deposit for brakes - 14: Chassis - 15: Bushing - 16: Brake rod.
The personnel who operates the trains
Trains, tracks, engineers, innovations, all of this has been mentioned so far, but not the important personages who populate the magic world of the railway: the personnel who travels and the personnel disseminated along the lines. In the same way that nowadays we can look with admiration the cosmonauts, similar feelings could have produced the first machinists. All dirty with soot, fighting all the time with steam valves and sudden frights, their figure could move the imagination because of the courage that they showed running their machines at crazy speeds, trying to keep the distances with infuriated peasants or even worse, American natives. Well different is the mood of the modern machinist who, contrarily to his predecessors, manages to drive those fast machines only after a long learning and practice, allowing him to master the most recondite aspects of the powerful machines entrusted to him.
The stationmaster of Naples in 1839 (left) and a railway operator from the late 19th century (right).
Manual railroad switch (left) and a level crossing in 1888 (right).
An early braking system in use in American freight wagons.
Countless pages could be written about the accidents happened or conjured in extremis; still today, unfortunately, the television and press bring the echoes of railway accidents and disgraces. The first accidents can be attributed to the limited capability of the manufacturers or the ignorance of the machinists; for example, that machinist who sit in a steam safety valve to silence the noise emitted by it, causing a general explosion of the boiler. Memorable was as well the incident happened in the eve of the year 1888, when an old locomotive operating in the line Baltimore-Ohio exploded with such a noise that it was heard up to eight kilometers around, but the machinists, by pure miracle, resulted unscathed.
Even more clamorous was maybe the accident happened in the station at Montparnasse: a locomotive which towed nine wagons, entering the station at quite high speed, because of a failure in the brakes could not stop nor reduce the speed; and jumping to the platform and destroying the wall ahead, the locomotive fell and overturned in the exterior esplanade, smashing a newspaper kiosk; the only victim was the woman in charge of the kiosk. Further ahead we will see how it has been attempted to reduce to the minimum the accidents and disgraces in spite of the intense traffic.
A locomotive fitted with snow sweeper
It had just begun the year 1836 when it arrived to Russia the locomotive built by Stephenson in the workshops at Newcastle. It was not an usual locomotive, but one provided with four sweepers to take away the snow from the track. Despite the inclement weather, there was a large number of onlookers waiting, along the line between Pavlovsk and Konzimin, the passing of the magnificent convoy which, however the furious blizzard, covered in just 17 minutes the seven verstas (7.5 kilometers) of distance, towing a load of 256 persons distributed in eight large wagons, performing later the return travel in equal time span, and now not towing the wagons, but pushing them, marching in reverse. A great success!
The gazettes and newspapers of that time highlighted this event during long time, and in the court of the Tzar soon circulated rumors about the next opening of other and more important lines. In the subsequent years these were built indeed, but they were of a relatively short length compared to the audacious projects of a general. In 1890 he was Emperor of Russia the Tzar Nicholas II. It was shortly after having fired the Prime Minister, when he was informed that a general called Mihail Annenkof requested to be received. Annenkof wanted to submit a project of him to the Tzar to achieve authorization to carry it out.Continue reading...