East Coast Main Line
The East Coast Main Line is a 393-mile long major railway between London and Edinburgh via Peterborough, York, Darlington and Newcastle. The route is a key transport artery on the eastern side of Great Britain and broadly paralleled by the A1 road; the line's origins were built during the 1840s by three railway companies, the North British Railway, the North Eastern Railway, the Great Northern Railway. In 1923, the enactment of the Railway Act of 1921 led to their amalgamation to form the London and North Eastern Railway; the line was the primary route of the LNER, who competed against the London and Scottish Railway for long-distance passenger traffic between London and Scotland. The LNER's chief engineer Sir Nigel Gresley designed iconic Pacific locomotives, including the steam locomotives "Flying Scotsman" and "Mallard" which achieved a world record speed for a steam locomotive, 126 miles per hour on the Grantham-to-Peterborough section. On 1 January 1948, the railways were nationalised by the government, operated by British Railways.
During the early 1960s, steam locomotion was replaced by Diesel-electric traction, including the Deltics and sections of the line were upgraded so trains could run at speeds of up to 100 miles per hour. With the demand for higher speed, British Rail introduced InterCity 125 High Speed trains between 1976 and 1981. In 1973, the prototype of the HST, the Class 41, achieved a top speed of 143 mph in a test run on the line. During the 1980s, the line was electrified and InterCity 225 trains were introduced; the line links London, South East England and East Anglia, with Yorkshire, the North East Regions and Scotland and is important to the economy of several areas of England and Scotland. It carries key commuter flows for the north side of London and handles cross-country and local passenger services, carries freight traffic. Services north of Edinburgh to Inverness use diesel trains. In 1997, operations were privatised; the current operator is London North Eastern Railway, bringing the LNER name back into use, which took over from Virgin Trains East Coast in June 2018.
The ECML is part of Network Rail's Strategic Route G which comprises six separate lines: The main line between London King's Cross and Edinburgh Waverley stations, via Stevenage, Grantham, Newark North Gate, Doncaster, Northallerton, Durham, Morpeth, Berwick-upon-Tweed and Dunbar. The line crosses the Anglo-Scottish border at Marshall Meadows Bay; the branch line to North Berwick The Dunbar loopThe core route is the main line between King's Cross and Edinburgh, the Hertford Loop is used for local and freight services and the Northern City Line provides an inner suburban service to the city. The route has ELRs ECM1 - ECM9; the ECML was constructed by three railway companies. During the 1830s and 1840s, each company built part of the line to serve their own areas, but intended linking together to form the through route that became the East Coast Main Line. From north to south, these companies were: the North British Railway, from Edinburgh to Berwick-upon-Tweed, completed in 1846; the North Eastern Railway from Berwick-upon-Tweed to Shaftholme.
The Great Northern Railway from Shaftholme to King's Cross, completed in 1850. The GNR established an end-on connection at Askern, described by the GNR's chairman as being "a ploughed field four miles north of Doncaster". Askern was connected to the Lancashire and Yorkshire Railway, a short section of which linked with the NER at Knottingley. In 1871, the line was shortened when the NER opened a direct line from an end-on junction with the GNR at Shaftholme just south of Askern to Selby and direct to York. Recognising that through journeys were an important and lucrative element of their businesses, the companies built special rolling stock for through traffic, services were operated under the name of "East Coast Joint Stock"; this continued from 1860 until 1922. In 1923 the Railway Act of 1921 required the companies to form North Eastern Railway. Throughout its existence, the LNER was the second largest railway company in Britain, with lines to the north and east of London. On 1 January 1948, after the Transport Act of 1947 was implemented by Clement Attlee's Labour Government, the LNER was nationalised with the other companies to form British Railways.
British Railways managed the ECML as its Eastern Region division up to discorporation during the early 1980s. Alterations to short sections of the ECML's route have taken place, including the King Edward VII Bridge in Newcastle upon Tyne in 1906 and the Selby Diversion, built to bypass mining subsidence from the Selby coalfield and a bottleneck at Selby station. During 1983, the Selby Diversion opened: it diverged from the ECML at Temple Hirst Junction, north of Doncaster, joined the Leeds to York Line at Colton Junction, south west of York; the old line between Selby and York is used as a cycleway. Mining subsidence affecting 200 metres of track 17 km to the east of Edinburgh, near Wallyford, led to a temporary realignment while the ground was stabilised; the tracks and overhead electrification equipment were re-routed. Stabilisation was completed in 2000 and the track returned to its original alignment. In 2001 severe subsidence occurred at Dolphingstone and about 2km of track was relocated avoiding a permanent speed restriction.
This was completed in 2002. The line was worked for many years
Walschaerts valve gear
The Walschaerts valve gear is a type of valve gear invented by Belgian railway mechanical engineer Egide Walschaerts in 1844 used to regulate the flow of steam to the pistons in steam engines. The gear is sometimes named without the final "s", since it was incorrectly patented under that name, it was extensively used in steam locomotives from the late 19th century until the end of the steam era. The Walschaerts valve gear was slow to gain popularity; the Stephenson valve gear remained the most used valve gear on 19th-century locomotives. However, the Walschaerts valve gear had the advantage that it could be mounted on the outside of the locomotives, leaving the space between the frames clear; the first locomotive fitted with the Walschaerts valve gear was built at the Belgian Tubize workshops, was awarded a gold medal at the 1873 Universal Exhibition in Vienna. In 1874 New Zealand Railways ordered two NZR B class locomotives, they were Double Fairlie locomotives, supplied by Avonside. They were Cape gauge.
The Mason Bogie, a modified Fairlie locomotive of 1874, was the first to use the Walschaerts gear in North America. The first application in Britain was on a Single Fairlie 0-4-4T, exhibited in Paris in 1878 and purchased by the Swindon and Andover Railway in March 1882. According to Ahrons, the locomotive saw little service as nobody seems to have known how to set the valves and this led to enormous coal consumption. In the 20th century, the Walschaerts valve gear was the most used type on larger locomotives. In Europe, its use was universal, whilst in North America, the Walschaerts gear outnumbered its closest competitor, the derived Baker valve gear, by a wide margin. In Germany and some neighbouring countries, like Poland and Czechoslovakia, the Walschaerts gear is named the Heusinger valve gear after Edmund Heusinger von Waldegg, who invented the mechanism independently in 1849. Heusinger's gear was closer to the form adopted, but most authorities accept Walschaerts' invention as sufficiently close to the final form.
The Walschaerts valve gear is an improvement on the earlier Stephenson valve gear in that it enables the driver to operate the steam engine in a continuous range of settings from maximum economy to maximum power. At any setting, the valve gear satisfies the following two conditions: The valve opens to admit steam to the cylinder just before the start of a piston stroke; the pressure of this steam provides the driving force. Soon before the space on one side of the piston starts to contract, the valve starts to release steam from that space to the atmosphere, so as not to impede the movement of the piston. In an economical setting, steam is admitted to the expanding space for only part of the stroke. Since the exhaust is shut, during the rest of the stroke the steam that has entered the cylinder expands in isolation, so its pressure decreases. Thus, the most energy available from the steam is used; the Walschaerts valve gear enables the engineer to change the cutoff point without changing the points at which intake starts.
Economy requires that the throttle be wide open and that the boiler pressure is at the maximum safe level to maximise thermal efficiency. For economy, a steam engine is used of a size such that the most economical settings yield the right amount of power most of the time, such as when a train is running at steady speed on level track; when greater power is necessary, e.g. when gaining speed when pulling out of a station and when ascending a gradient, the Walschaerts valve gear enables the engineer to set the cutoff point near the end of the stroke, so that the full pressure of the boiler is exerted on the piston for the entire stroke. With such a setting, when the exhaust opens, the steam in the cylinder is near full boiler pressure; the pressure in the steam at that moment serves no useful purpose. This sudden pulse of pressure causes the loud “choo” sound that members of the public associate with steam engines, because they encounter engines at stations, where efficiency is sacrificed as trains pull away.
A steam engine well adjusted for efficiency makes a soft “hhHHhh” sound that lasts throughout the exhaust stroke, with the sounds from the two cylinders overlapping to produce a nearly constant sound. The valve gear operation combines two motions; the secondary is the directional/amplitude motion, imparted at the top. Consider that the driver has adjusted the reversing lever such that the die block is at mid-gear. In this position the secondary motion is eliminated and the piston valve travel is shortest, giving minimal injection and exhaust of steam; the travel of the piston valve is twice the total of lap plus lead. Contrast this to when the die block is at the bottom of the expansion link, giving maximum steam injection and exhaust; this is used in accelerating forward from rest. Conversely when the die block is at the top of the expansion link, maximal power in reverse is obtained. Once the locomotive has accelerated the driver can adjust the reverser toward the mid-gear position, decreasing cut-off to give a more economical use of steam.
The engine's tractive e
GCR Class 8
The Great Central Railway Class 8 - London North Eastern Railway Class B5 - was a class of 4-6-0 steam locomotives. They were nicknamed "Fish Engines" on delivery, due to their use on the fast fish deliveries from Grimsby to places like London, the duty they were designed for; the last was withdrawn in 1950. A 1/5 scale, 10.25 in gauge model of number 181 has been made by Andrew Simkins. This model is externally faithful to Robinson's design but cleverly uses a footwell to conceal most of the driver in the tender, it was showcased and won an award at the Model engineering exhibition in 2003. It has since been seen on several of the 10.25 in gauge railways around Britain. Boddy, M. G.. A.. V.. N. T.. B.. Locomotives of the L. N. E. R. Part 2B: Tender Engines - Classes B1 to B19. Lincoln: RCTS. ISBN 0-901115-73-8. OCLC 655688865. Casserley, H. C.. W. Johnson. Locomotives at the Grouping 2: London and North Eastern Railway. Shepperton, Surrey: Ian Allan Limited. Pp. 12, 107, 111. ISBN 0-7110-0553-2. LNER Encyclopedia
The leading wheel or leading axle or pilot wheel of a steam locomotive is an unpowered wheel or axle located in front of the driving wheels. The axle or axles of the leading wheels are located on a leading truck. Leading wheels are used to help the locomotive negotiate curves and to support the front portion of the boiler; the leading bogie does not have simple rotational motion about a vertical pivot, as might first be thought. It must be free to slip sideways to a small extent, some kind of springing mechanism is included to control this movement and give a tendency to return to centre; the sliding bogie of this type was patented by William Adams in 1865. The first use of leading wheels is attributed to John B. Jervis who employed them in his 1832 design for a locomotive with four leading wheels and two driving wheels. In the Whyte system of describing locomotive wheel arrangements, his locomotive would be classified as a 4-2-0: That is to say, it had four leading wheels, two driving wheels, no trailing wheels.
In the UIC classification system, which counts axles rather than wheels and uses letters to denote powered axles, the Jervis would be classified 2A. Locomotives without leading trucks are regarded as unsuitable for high speed use; the British Railway Inspectorate condemned the practice in 1895, following an accident involving two 0-4-4s at Doublebois, Cornwall, on the Great Western Railway. Other designers, persisted with the practice and the famous 0-4-2 Gladstone class passenger expresses of the London and South Coast Railway remained in trouble-free service until 1933. A single leading axle increases stability somewhat, while a four-wheel leading truck is essential for high-speed operation; the highest number of leading wheels on a single locomotive is six, as seen on the 6-2-0 Crampton type and the Pennsylvania Railroad's 6-4-4-6 S1 duplex locomotive and 6-8-6 S2 steam turbine. Six-wheel leading trucks were not popular; the Cramptons were built in the 1840s, but it was not until 1939 that the PRR used one on the S1.
AAR wheel arrangement Adams axle Trailing wheel UIC classification of locomotive axle arrangements Whyte notation
GCR Class 8B
GCR Class 8B was a class of 25 two-cylinder steam locomotives of the 4-4-2 wheel arrangement built between 1903 and 1906 for the Great Central Railway. Facing a potential rise in passenger traffic, the Great Central Railway placed an order for 2 pairs of different locomotives - one pair being the 4-6-0 GCR Class 8C, the other pair being this 4-4-2 locomotive; the two locomotives shared as many common components as possible to allow easy conversion of the 8Bs to the 4-6-0 configuration - and both designs borrowed from John G. Robinson's earlier GCR Class 8. However, due to a much smaller than anticipated traffic increase, no further Class 8Cs were built, instead a further 25 Class 8Bs were ordered and built between 1904 and 1906 - built with larger fireboxes as there was no longer a need to convert the locomotives to a 4-6-0 configuration. In 1909 and 1910, the original locomotives received this larger firebox. Despite Robinson commencing the conversion to superheaters in 1912, the conversion was not completed until 1936.
At the same time, any locomotive requiring cylinder replacement saw both larger cylinders and piston valves being fitted - 20 of the class would receive this modification. From 1921, the Ramsbottom safety valves were phased out and removed, to be replaced by Ross pop safety valves. Following a high-speed incident that caused severe damage to its frame and cylinders, No. 1090 was rebuilt with 3 simple expansion cylinders in 1908, as a comparison to the GCR Classes 8D and 8E. These cylinders had their Stephenson valve gear replaced with Walschaerts valve gear, the only application of this valve gear, excluding railcars, on a GCR locomotive; the experiment was reverted in 1922 when No. 1090 was rebuilt, with the original 2 cylinders and Stephenson valve gear being refitted. Following the merger of the GCR into the London & North Eastern Railway, the class became known as the LNER Class C4. In 1925, several C4s were fitted with the LNER's trademark "Flowerpot" chimney, with one locomotive, No. 6085 modified to fit the LNER composite gauge - a modification that the remainder of the class underwent between 1936 and 1939.
In 1929, a further LNER classification change was made - the non-superheated locomotives were designated Class C4/1, those fitted with superheaters but still utilized slide valves Class C4/2, those with both superheaters and piston valves became Class C4/3. By 1932, the re-gauged No. 6085 had been given the designation Class C4/4 - which became more populated as Class C4/3s were cut down. By 1939, all Class C4/1s and Class C4/3s had been redesignated as either Class C4/2s or Class C4/4s - by this time all locomotives were both superheated and had been cut down to the LNER composite gauge. Following an accident at Banbury in 1939, the first locomotive, No. 6090, was withdrawn from service. The rest of the class began being withdrawn from 1945, although 20 locomotives made it into British Rail hands following the nationalisation of the British railways; the last locomotive was withdrawn in 1950, none survived into preservation. The Robinson C4 4-4-2 Atlantics
The valve gear of a steam engine is the mechanism that operates the inlet and exhaust valves to admit steam into the cylinder and allow exhaust steam to escape at the correct points in the cycle. It can serve as a reversing gear, it is sometimes referred to as the "motion". In the simple case, this can be a simple task as in the internal combustion engine in which the valves always open and close at the same points; this is not the ideal arrangement for a steam engine, because greatest power is achieved by keeping the inlet valve open throughout the power stroke while peak efficiency is achieved by only having the inlet valve open for a short time and letting the steam expand in the cylinder. The point at which steam stops being admitted to the cylinder is known as the cutoff, the optimal position for this varies depending on the work being done and the tradeoff desired between power and efficiency. Steam engines are fitted with regulators to vary the restriction on steam flow, but controlling the power via the cutoff setting is preferable since it makes for more efficient use of boiler steam.
A further benefit may be obtained by admitting the steam to the cylinder before front or back dead centre. This advanced admission assists in cushioning the inertia of the motion at high speed. In the internal combustion engine, this task is performed by cams on a camshaft driving poppet valves, but this arrangement is not used with steam engines because achieving variable engine timing using cams is complicated. Instead, a system of eccentrics and levers is used to control a D slide valve or piston valve from the motion. Two simple harmonic motions with different fixed phase angles are added in varying proportions to provide an output motion, variable in phase and amplitude. A variety of such mechanisms have been devised with varying success. Both slide and piston valves have the limitation that intake and exhaust events are fixed in relation to each other and cannot be independently optimised. Lap is provided on steam edges of the valve, so that although the valve stroke reduces as cutoff is advanced, the valve is always opened to exhaust.
However, as cutoff is shortened, the exhaust events advance. The exhaust release point occurs earlier in the power stroke and compression earlier in the exhaust stroke. Early release wastes some energy in the steam, early closure wastes energy in compressing an otherwise unnecessarily large quantity of steam. Another effect of early cutoff is that the valve is moving quite at the cutoff point, this causes'wire drawing' of the steam, another wasteful thermodynamic effect visible on an indicator diagram; these inefficiencies drove the widespread experimentation in poppet valve gears for locomotives. Intake and exhaust poppet valves could be moved and controlled independently of each other, allowing for better control of the cycle. In the end, not a great number of locomotives were fitted with poppet valves, but they were common in steam cars and lorries, for example all Sentinel lorries and railcars used poppet valves. A late British design, the SR Leader class, used sleeve valves adapted from internal combustion engines, but this class was not a success.
In stationary steam engines, traction engines and marine engine practice, the shortcomings of valves and valve gears were among the factors that lead to compound expansion. In stationary engines trip valves were extensively used. Valve gear was a fertile field of invention, with several hundred variations devised over the years. However, only a small number of these saw any widespread use, they can be divided into those that drove the standard reciprocating valves, those used with poppet valves, stationary engine trip gears used with semi-rotary Corliss valves or drop valves. Slip-eccentric - This gear is now confined to model steam engines, low power hobby applications such as steam launch engines, ranging to a few horsepower; the eccentric is loose on the crankshaft but there are stops to limit its rotation relative to the crankshaft. Setting the eccentric to the forward running and reverse running positions can be accomplished manually by rotating the eccentric on a stopped engine, or for many engines by turning the engine in the desired rotation direction, where the eccentric positions itself automatically.
The engine is pushed forwards to put the eccentric in the forward gear position and backwards to put it in the backward gear position. There is no variable control of cutoff. On the London and North Western Railway, some of the three-cylinder compounds designed by Francis William Webb from 1889 used a slip eccentric to operate the valve of the single low-pressure cylinder; these included Greater Britain and John Hick classes. Gab or hook gear - used on earliest locomotives. Allowed reversing but no control of cutoff. One component of the motion comes from a eccentric; the other component comes from a separate source the crosshead. Walschaerts or Heusinger valve gear - most common valve gear on locomotives externally mounted. Deeley valve gear - fitted to several express locomotives on the Midland Railway; the combination levers were driven, as normal, from the crossheads. Each expansion link was driven from the crosshead on the opposite side of the engine. Young valve gear - used the piston rod motion on one side of the locomotive to drive the valve gear on the other side.
Similar to the Deeley gear, but with deta