Specialised Engineering Rolling Stock
Railways were originally very labour intensive. This applied particularly to the civil engineering activities involved in both laying and maintaining the permanent way and its supporting earthworks.
Early etchings of railway building activities show that a great deal was achieved by sheer weight of manpower assisted only by hand tools, wheelbarrows and the trusty horse. Contractors often laid temporary track on which they used their own small steam locomotives hauling simple wagons. On these tracks some used simple steam powered mobile cranes but that was about the limit of mechanical plant available.
On railways today engineers have designed many items of plant, both stationary and mobile, which reduce considerably the manual tasks associated with keeping the track up to a good standard.
All specialised engineering rolling stock has to comply with all the safety, signalling and operational requirements on the railway. Some is self propelled and can be treated as a train operating in its own right. Other plant is hauled to site as part of a train and only operated under its own power within the confines of a complete possession of the railway. Specialised vehicles included the following:
•Ballast tamping machines
•Ballast hopper wagons
•Mobile rail cranes
•Long welded rail cars
•Snow and leaf clearing vehicles
•Battery cars/Ballast locomotives
•Track recording cars
•Special flat cars/bolster wagons for track.
Originally railway rolling stock was manufactured using simple engineering skills with most components being ?bespoke'.Manufacture was which was relatively cheap. In more recent years multiple engineering skills have become involved with more specialisation, complex design and use of standard components. Skilled labour has become progressively more expensive in real terms. Additionally there have been a number of major changes in manufacturing technology.
These changes include the following:
•Riveting has been replaced by welding.
•There is an increase in the use of aluminium and stainless steel.
•Plastics have been introduced.
•There is a greater use of jigs and fixtures.
•Computerised manufacture and production control.
•Introduction of quality assurance.
The Origin and Development of Railway Track
Before the beginning of the eighteenth century wheeled transport was generally hauled by horse and ran on surfaces which at the best was reinforced by a broken stone foundation and at the worst was simply a mud track. It was found at a very early stage of the development of land transport, that most road surfaces and foundations were very quickly damaged by heavy wagons on rigid wheels.
The first railway tracks were laid down in the eighteenth century for horse drawn trains of wagons in collieries a initially had a surface of stone slabs or timber baulks which proved unsatisfactory as loads grew heavier. As the Industrial Revolution progressed the idea was developed further by adding wrought iron plates to reduce wear on the wooden baulks. This evolved further first to cast iron plates and later to edge rails, enabling for the first time the use of flanged iron wheels. By the time locomotives came on the scene in the early nineteenth century, wrought iron rails had developed further and became strong enough to support these heavy engines without assistance from longitudinal timbers. In 1825 the Stockton and Darlington Railway was constructed adopting track of wrought iron rails resting in cast iron chairs supported on stone blocks set in the ground at three feet intervals. The rails were o 15 feet long and weighed about 28 lbs per yard.
As experience was gained and new technology evolved, rails steadily increased in size, both in length and cross section, and were made in steel rather than iron. Early railways evolved the ?bullhead' o of rail which was standard throughout the UK up to the SecondWorldWar.
This rail was manufactured in increasing lengths and heavier sections and by the early 1900's had0 footbeenlengths andgenerally stand about 95 lbs per yard weight. Most railways today use flat-bottomed rail.
The individual stone block sleepers were early found to be unwieldy and unsatisfactory from several points of view, largely relating to weight and the lack of tying of rails at a fixed gauge. These blocks were quickly replaced by timber cross sleepers which proved to be much more economic and satisfactory.
Cross sleepers, or ?ties' as they are known generally adopted worldwide and are now often manufactured in concrete or steel although timber is still used extensively. At a very early stage the need for good preservation of softwood left in wet ballast became very obvious.
By the 1880's several railwayts companies had to impregnate sleepers with creosote under pressure.