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 cleaners
•Ballast hopper wagons
•Stone blowers
•Mobile rail cranes
•Long welded rail cars
•Cleaning trains
•Inspection
cars/trolleys
•Snow and leaf clearing
vehicles
•Concreting trains
•Drain/sump cleaners
•Battery cars/Ballast
locomotives
•Tunnel cleaners
•Platelayers' trolleys
•Personnel carriers
•Track recording cars
•Rail grinders
•Special flat
cars/bolster wagons for track.
Manufacturing Methods
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•Riveting has been
replaced by welding.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.
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