A wheeltapper is a railway worker employed to check the structural integrity of train wheels and that axle boxes are not overheating.
Typically employed at large urban railway stations and in goods yards, they tap wheels with a long-handled hammer and listen to the sound made to determine the integrity of the wheel; cracked wheels, like cracked bells, do not sound the same as their intact counterparts (they do not "ring true").
Wheeltappers also check that the axle boxes are not too hot by using the back of their hand. [1] [2]
Although wheeltappers still operate in some eastern European countries, in countries with modern planned maintenance procedures and line-side defect detectors, such as hot box detectors, wheeltappers are redundant. The job is mostly associated with the steam age. Wheeltappers were vital to the smooth running of the railways as a cracked wheel or overheated axle bearing would lead to delays and the loss of revenue. These were particularly common in the 19th century, when axle bearings were lubricated by grease. At this time, metallurgy was a more haphazard science and thus it was impossible to test steel wheels for cracks: the role of the wheeltapper was of crucial importance. [3] [4]
There is an anecdote of a wheeltapper who had worked diligently for years wheeltapping without ever questioning or understanding the purpose. This originated with Rudyard Kipling in Delhi, and is referenced in his work Captains Courageous of 1897, [5] [6] [7] although it had spread to the United States by 1932. [3] [4] Another version of the tale is told in the 1937 Will Hay British comedy film Oh, Mr Porter! A German version of the story was told by the German humourist Sigismund von Radecki. [8]
In Tolstoy's Anna Karenina , a railway worker is accidentally killed. He is probably a wheeltapper, and the man's gruesome death anticipates Anna's eventual suicide.
A bogie comprises two or more wheelsets, in a frame, attached under a vehicle by a pivot. Bogies take various forms in various modes of transport. A bogie may remain normally attached or be quickly detachable. It may include suspension components within it, or be solid and in turn be suspended. It may be mounted on a swivel, as traditionally on a railway carriage or locomotive, additionally jointed and sprung, or held in place by other means.
A rubber-tyred metro or rubber-tired metro is a form of rapid transit system that uses a mix of road and rail technology. The vehicles have wheels with rubber tires that run on a roll way inside guide bars for traction. Traditional, flanged steel wheels running on rail tracks provide guidance through switches and act as backup if tyres fail. Most rubber-tyred trains are purpose-built and designed for the system on which they operate. Guided buses are sometimes referred to as 'trams on tyres', and compared to rubber-tyred metros.
A rack railway is a steep grade railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail. This allows the trains to operate on steep gradients of 100% or more, well above the 10% maximum for friction-based rail. The rack and pinion mechanism also provides more controlled braking and reduces the effects of snow or ice on the rails. Most rack railways are mountain railways, although a few are transit railways or tramways built to overcome a steep gradient in an urban environment. The first cog railway was the Middleton Railway between Middleton and Leeds in West Yorkshire, England, United Kingdom, where the first commercially successful steam locomotive, Salamanca, ran in 1812. This used a rack and pinion system designed and patented in 1811 by John Blenkinsop.
Puffing Billy is the world's oldest surviving steam locomotive, constructed in 1813–1814 by colliery viewer William Hedley, enginewright Jonathan Forster and blacksmith Timothy Hackworth for Christopher Blackett, the owner of Wylam Colliery near Newcastle upon Tyne, in the United Kingdom. It was employed to haul coal chaldron wagons from the mine at Wylam to the docks at Lemington in Northumberland.
Rail transport terms are a form of technical terminology applied to railways. Although many terms are uniform across different nations and companies, they are by no means universal, with differences often originating from parallel development of rail transport systems in different parts of the world, and in the national origins of the engineers and managers who built the inaugural rail infrastructure. An example is the term railroad, used in North America, and railway, generally used in English-speaking countries outside North America and by the International Union of Railways. In English-speaking countries outside the United Kingdom, a mixture of US and UK terms may exist.
Main components found on a typical steam locomotive include:
Under the Whyte notation for the classification of steam locomotives, 4-2-0 represents the wheel arrangement of four leading wheels on two axles, two powered driving wheels on one axle and no trailing wheels. This type of locomotive is often called a Jervis type, the name of the original designer.
In rail transport, a derailment is a type of train wreck that occurs when a rail vehicle such as a train comes off its rails. Although many derailments are minor, all result in temporary disruption of the proper operation of the railway system and they are a potentially serious hazard.
Under the Whyte notation for the classification of steam locomotives, 4-2-4 represents the wheel arrangement of four leading wheels on two axles, two powered driving wheels on one axle, and four trailing wheels on two axles.
The Meigs Elevated Railway was an experimental but unsuccessful 19th century elevated steam-powered urban rapid transit system, often described as a monorail but technically pre-electric third rail. It was invented in the US by Josiah Vincent Meigs, of Lowell, Massachusetts, and was demonstrated from 1886 to 1894 in a suburb of Boston called East Cambridge.
A track circuit is an electrical device used to prove the absence of a train on rail tracks to signallers and control relevant signals. An alternative to track circuits are axle counters.
An adhesion railway relies on adhesion traction to move the train, and is the most widespread and common type of railway in the world. Adhesion traction is the friction between the drive wheels and the steel rail. Since the vast majority of railways are adhesion railways, the term adhesion railway is used only when it is necessary to distinguish adhesion railways from railways moved by other means, such as by a stationary engine pulling on a cable attached to the cars or by a pinion meshing with a rack.
A coupling rod or side rod connects the driving wheels of a locomotive. Steam locomotives in particular usually have them, but some diesel and electric locomotives, especially older ones and shunter locomotives, also have them. The coupling rods transfer the power of drive to all wheels.
Hunting oscillation is a self-oscillation, usually unwanted, about an equilibrium. The expression came into use in the 19th century and describes how a system "hunts" for equilibrium. The expression is used to describe phenomena in such diverse fields as electronics, aviation, biology, and railway engineering.
William Bridges Adams was an English locomotive engineer, and writer. He is best known for his patented Adams axle – a successful radial axle design in use on railways in Britain until the end of steam traction in 1968 – and the railway fishplate. His writings, including English Pleasure Carriages (1837) and Roads and Rails (1862) covered all forms of land transport. Later he became a noted writer on political reform, under the pen name Junius Redivivus ; a reference to a political letter writer of the previous century.
The South African Railways Class 21 2-10-4 of 1937 was a class of steam locomotives used in South Africa.
The South African Railways Class 6Z 2-6-4 of 1901 was a steam locomotive from the pre-Union era in the Cape of Good Hope.
The Natal Government Railways 4-6-2TT Havelock of 1888 was a South African steam locomotive from the pre-Union era in the Natal Colony.
Steam springs or steam suspension are a form of suspension used for some early steam locomotives designed and built by George Stephenson. They were only briefly used and may have been used for fewer than ten locomotives.
The South African Railways Dutton road-rail tractors of 1923 were road-rail steam tractors.