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Tender Locomotives 4-2-2 “Single”[Inhalt]
UIC Classification 2'A1
GNR Stirling Single at the National Railway Museum, York
GNR Stirling Single at the National Railway Museum, York
Irid Escent

The wheel arrangement 4-2-2 designates a steam locomotive in which there is a leading, two-axle bogie, a driving axle and a fixed trailing axle. In different countries, this wheel arrangement is referred to as follows:

SingleUIC2'A1Whyte4-2-2 Switzerland1/4France211Turkey14

The first locomotives of this type date back to the 1840s and some still had fixed leading axles. Strictly speaking, these had the UIC wheel arrangement 2A1 instead of 2'A1. These included the “Borsig” of the Berlin-Anhalt Railway, the “Cornwall” of the LNWR and the Iron Duke class of the GWR. With the state of the art at that time, this wheel arrangement was only successful on the broad gauge of the GWR, since there were fewer tight curves. Thus, for express locomotives the wheel arrangement 2-2-2 was predominantly used.

Replica of the GWR “Iron Duke” with fixed leading axles
Replica of the GWR “Iron Duke” with fixed leading axles
Richard Kelly

The first locomotive with this wheel arrangement with a bogie was built in 1853 by Archibald Sturrock for the Great Northern Railway. At first there was only one locomotive with the number 215, which was initially tested. It was found that this locomotive tended to derail relatively easily.

Only with the further development of technology was it possible to get a better grip on the running characteristics. From around 1870, locomotives with a 4-2-2 wheel arrangement were increasingly being built, almost all of them coming from Great Britain. Probably the best-known representatives here were the Singles that Patrick Stirling had made for the Great Northern between 1870 and 1895.

When it came to hitting high speeds, the advantages of the Singles were obvious. The 2-2-2 wheel arrangement was now difficult to implement because the maximum weight with three axles limited power. The fourth axle allowed a larger boiler to be fitted while still accommodating wheels eight feet and larger in diameter. Although this wheel diameter reduced tractive effort, it meant less steam consumption at high speeds, reducing the required size of the boiler. The omission of an additional coupled axle and the coupling rods also reduced friction.

The number 385 of the Philadelphia & Reading was one of the few 4-2-2s built outside Great Britain
The number 385 of the Philadelphia & Reading was one of the few 4-2-2s built outside Great Britain
US National Park Service

However, it wasn't long before the Singles' pulling power was stretched to the limit given the increased weights of the express trains. More and more locomotives with a 4-4-0 wheel arrangement were used in front of British express trains, which had greater tractive power at a slightly lower maximum speed.

Only the development of a steam-powered sander in 1886 at the Midland Railway led to the 4-2-2 wheel arrangement being once again used. They had sufficient pulling power for the fastest express trains, which were slightly lighter in weight. Especially in the “Race to the North”, where various railway companies wanted to find the fastest connection from London to Scotland on two routes, the Singles could reach average speeds of more than 60 mph

In Great Britain the last Singles were built around the turn of the century and were then mainly replaced by Atlantic (4-4-2) locomotives. As late as 1910, Kerr, Stuart was able to export four 4-2-2 locomotives to the Shanghai-Nanjing railway, which had the largest boiler of any British single-driver locomotive. In the USA, only the Philadelphia & Reading had procured two locomotives with this wheel arrangement in newer times, which had to pull the lightest and fastest express trains.

Caledonian Single No. 123
London, Midland & Scottish class 1P
Great Britain | 1886 | only one produced
Locomotive Magazine, October 1903

For the 1886 World's Fair in Edinburgh, the Caledonian Railway had a single locomotive built with seven-foot wheels that would be able to travel at a very high average speed. The 4-4-0 of the class 66 by Dugald Drummond was used as the basis, in which the rear coupled axle was replaced by a trailing axle and the remaining driving axle was equipped with larger wheels. In order to be able to compensate for the low adhesion mass, a modern sanding system was used. Although a steam-powered system was just being introduced at the time, a different approach was being pursued here. Because Caledonian used Westinghouse air brakes instead of the vacuum brakes common in Britain, the compressed air was used to power the sand.

No. 123 in the Glasgow Transportation Museum
No. 123 in the Glasgow Transportation Museum
Hugh Llewelyn

After the World's Fair, locomotive number 123 was used in express service on the West Coast Main Line in Scotland. In the years 1888 and 1889 it got caught in the middle of the “Race to the North”, in which various railway companies on the east and west coasts unofficially tried to find the fastest journey time from London to Edinburgh. With often only two or three passenger cars, the locomotive did very well despite the inclines. On the 100 miles long section from Carlisle, average speeds of over 50 mph were regularly reached, on one occasion even 59. In addition to being used in front of heavier trains in combination with another locomotive, it was also used for special tasks. These included passenger trains for the Caledonian's inspectors and directors, and also repeatedly used as the lead locomotive for the royal family's train when they were en route to Balmoral Castle. The locomotive was taken over by the LMS in 1923 and was not withdrawn until 1935, making it the last British express locomotive with only one driving axle. From 1958 it ran again in front of special trains and is now in the Transport Museum in Glasgow.

General
Built1886
ManufacturerNeilson & Co.
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase21 ft 1 in
Total wheelbase42 ft 6 in
Empty weight84,896 lbs
Service weight92,848 lbs
Adhesive weight38,080 lbs
Total weight167,328 lbs
Axle load38,080 lbs
Water capacity3,423 us gal
Fuel capacity11,200 lbs (coal)
Power
Power sourcesteam
Estimated power550 hp (410 kW)
Optimal speed27 mph
Starting effort12,786 lbf
Power Plant
Driver diameter84 in
Boiler pressure150 psi
Expansion typesimple
Cylinderstwo, 18 x 26 in
Boiler
Grate area17.4 sq ft
Firebox area112 sq ft
Tube heating area941 sq ft
Evaporative heating area1,053 sq ft
Total heating area1,053 sq ft
Calculated Values
steam locomotive
express
Dugald Drummond
last changed: 01/2022
Shanghai-Nanjing Railway class D
China | 1910 | 4 produced
Locomotive Magazine, August 1910

After the Class C with a 4-4-0 wheel arrangement and 6 ft 7 in wheels, the Shanghai-Nanjing Railway ordered four more locomotives that were to have even larger wheels. Using a boiler that was largely the same as that of existing classes of the company, one driving axle now had to be sufficient. Despite this, the boiler was the largest ever to be found on a British-made single-driver locomotive.

The engines were intended for express traffic as part of a large trade fair in Nanjing and should be up and running within 45 days of receipt of the order. Despite the national mourning for the death of King Edward and the Pentecost holidays, the time had come after 47 days. Their special position was underlined by the fact that they were painted in a bright yellow instead of the usual green.

General
Built1910
ManufacturerKerr, Stuart & Co.
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length57 ft 3 3/4 in
Wheelbase25 ft 2 in
Total wheelbase48 ft 9 in
Service weight125,552 lbs
Total weight221,088 lbs
Water capacity4,203 us gal
Fuel capacity15,680 lbs (coal)
Power
Power sourcesteam
Estimated power1,000 hp (746 kW)
Optimal speed42 mph
Starting effort15,344 lbf
Power Plant
Driver diameter84 in
Boiler pressure180 psi
Expansion typesimple
Cylinderstwo, 18 x 26 in
Boiler
Grate area28 sq ft
Firebox area182.6 sq ft
Tube heating area1,467.4 sq ft
Evaporative heating area1,650 sq ft
Total heating area1,650 sq ft
Calculated Values
steam locomotive
express
last changed: 08/2022
Great Central class 13
Great Britain | 1900 | 6 produced
Locomotive Engineering, July 1900

The Great Central Railway Class 13 was the last single-driver express locomotive to be built in Britain and one of the last to see regular service. It was developed by Harry Pollitt, who called it Type X4. It had 7 feet 9 inches diameter wheels and had a boiler pressure of 200psi from the factory. Since, despite the sophisticated sanding system that was obligatory on the last singles, there was more power than could be converted into traction, the boiler pressure was soon reduced to 160 psi

When Pollitt retired in 1900 and John G. Robinson took over as chief engineer at GCR, the class 13 was just being produced. Anticipating the imminent end of the singles, Robinson reduced the order from ten to six. These locomotives initially ran the important route from Sheffield to London, but were moved to Cheshire in 1903 and replaced by the 4-4-0 Robinson class D4 locomotives. Four examples were fitted with a superheater between 1915 and 1919, but they were all retired between 1923 and 1927.

Variantas builtsuperheated
General
Built19001915-1919
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length54 ft 9 in
Wheelbase22 ft 11 in
Total wheelbase45 ft 5 in
Service weight105,840 lbs111,664 lbs
Adhesive weight41,104 lbs
Total weight200,480 lbs207,984 lbs
Axle load41,104 lbs
Fuel capacitycoal
Power
Power sourcesteam
Estimated power750 hp (559 kW)850 hp (634 kW)
Optimal speed26 mph37 mph
Starting effort18,072 lbf14,458 lbf
Power Plant
Driver diameter93 in
Boiler pressure200 psi160 psi
Expansion typesimple
Cylinderstwo, 19 1/2 x 26 in
Boiler
Grate area24.8 sq ft
Firebox area132 sq ft128 sq ft
Tube heating area1,062 sq ft777 sq ft
Evaporative heating area1,194 sq ft905 sq ft
Superheater area138 sq ft
Total heating area1,194 sq ft1,043 sq ft
Calculated Values
steam locomotive
express
Harry Pollitt
last changed: 04/2022
Great Eastern class P43
Great Britain | 1898 | 10 produced
Locomotive Magazine, August 1899

The Great Eastern Railway's P43 class was the penultimate single-driver express locomotive built in Britain, before the GCR Class 13. Although the GER was already using four-coupled passenger locomotives, its seven-foot wheels were used to pull light express trains. The usual area of application included the fastest possible transport of wealthy customers from the City of London to the North Sea coast in Norfolk.

Its developer James Holden is considered one of the pioneers of oil firing, and so the P43 also had oil firing. This could be seen in the different shape of the tender, which was also prepared for conversion to coal. As an oil tender, it held 715 gallons of oil and 2,790 gallons of water. The necessary pre-heating of the oil was accomplished by feeding the oil in the tender through a tube through which the exhaust steam from the brake system ejector was also fed.

Schematic drawing
Schematic drawing
Locomotive Magazine, June 1912

Even if they had slightly smaller driving wheels compared to other British singles and the adhesive weight was low for the time around the turn of the century, they were initially able to hold their own with their light trains on the relatively flat route. Nevertheless, the first two of the ten locomotives were retired in 1907, followed by five in 1908, one in 1909 and the last two in 1910. They were replaced by the 4-4-0 locomotives of classes S45, D56 and H88, also developed by Holden, which were called “Claud Hamilton”.

General
Built1898
ManufacturerStratford
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase22 ft 9 in
Total wheelbase43 ft 10 in
Service weight109,760 lbs
Adhesive weight42,560 lbs
Total weight190,400 lbs
Axle load42,560 lbs
Water capacity3,351 us gal
Fuel capacity859 us gal (oil)
Power
Power sourcesteam
Estimated power700 hp (522 kW)
Optimal speed33 mph
Starting effort13,639 lbf
Power Plant
Driver diameter84 in
Boiler pressure160 psi
Expansion typesimple
Cylinderstwo, 18 x 26 in
Boiler
Grate area21.3 sq ft
Firebox area114.2 sq ft
Tube heating area1,178.8 sq ft
Evaporative heating area1,293 sq ft
Total heating area1,293 sq ft
Calculated Values
steam locomotive
express
James Holden
last changed: 02/2022
Great Northern (UK) Stirling Single
Great Britain | 1870 | 53 produced
ETH Zürich

Patrick Stirling believed that locomotives with large wheels would not only be suitable for higher speeds, but would also achieve better traction. So he borrowed a 2-2-2 locomotive from the Great Eastern and used it to develop a significantly larger locomotive. By adding a two-axle leading bogie, guidance at higher speeds was improved and the increased weight was better distributed.

The no longer operational No. 1 in July 2003 in Doncaster
The no longer operational No. 1 in July 2003 in Doncaster
Our Phellap

The driving wheels were eight feet and one inch in diameter, equivalent to 2,464 mm. The cylinders were very large at 18 by 28 inches in order to still be able to convert enough steam at the lower rotational speeds of the large wheels. In order to be able to position the boiler low despite the large cylinders and also to avoid the problems with cranked axles and high forces, the cylinders were arranged on the outside. Between 1870 and 1895 a total of 53 were manufactured, which became increasingly heavier and had a higher boiler pressure.

sectional drawing
sectional drawing
Locomotive Magazine, February 1902

The Singles were also used on heavier trains on the flat line between London and York with an average speed of around 50 mph or 80 km/h. Trains with ten to 16 three-axle coaches that weighed between 150 and 240 tons in total were common on lines that rarely had a gradient of more than 1 in 200 and a maximum of 1 in 95. With lighter trains, they could reach speeds of up to 85 mph or 137 km/h.

In the “Race to the North” they ran lighter trains at average speeds of more than 60 mph or 97 km/h. Even with heavier trains, there were strict instructions not to use pilot locomotives in order to showcase the performance of the Singles. After there were two derailments in 1895 and 1896 due to the high axle load on the driving axle, the weight was reduced.

At the turn of the century, the trains became too heavy for the Singles, so pilot locomotives were now used. With the introduction of Ivatt's Atlantics in 1898, the area of operation also shifted to less important trains. Nevertheless, some received a larger domed boiler by Ivatt. After the last ones were retired by 1916, only number 1 remained as the oldest Single from 1870. It ran for the last time in 1985 and is now in the National Railway Museum in York.

Variant1870 variant1884 variant1894 variant
General
Built187018841894-1895
ManufacturerDoncaster
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length50 ft 7 in
Length loco29 ft29 ft 11 in
Wheelbase22 ft 10 in22 ft 1 in23 ft 3 in
Fixed wheelbase8 ft 8 in9 ft
Service weight86,128 lbs101,136 lbs110,992 lbs
Adhesive weight33,600 lbs38,080 lbs43,904 lbs
Total weight146,608 lbs175,924 lbs204,400 lbs
Axle load33,600 lbs38,080 lbs43,904 lbs
Water capacity3,223 us gal3,483 us gal4,624 us gal
Fuel capacity7,840 lbs (coal)11,200 lbs (coal)
Power
Power sourcesteam
Estimated power550 hp (410 kW)575 hp (429 kW)650 hp (485 kW)
Optimal speed32 mph29 mph26 mph
Starting effort11,130 lbf12,654 lbf15,965 lbf
Power Plant
Driver diameter97 in97.5 in
Boiler pressure140 psi160 psi172 psi
Expansion typesimple
Cylinderstwo, 18 x 28 intwo, 19 1/2 x 28 in
Boiler
Grate area17.6 sq ft17.8 sq ft20 sq ft
Firebox area122 sq ft109 sq ft121.7 sq ft
Tube heating area1,043 sq ft936 sq ft910 sq ft
Evaporative heating area1,165 sq ft1,045 sq ft1,031.7 sq ft
Total heating area1,165 sq ft1,045 sq ft1,031.7 sq ft
Calculated Values
steam locomotive
express
Patrick Stirling
last changed: 01/2024
Great Western Railway Iron Duke and Rover class
Great Britain | 1846 | 49 produced
Replica of the Iron Duke at the National Railway Museum, York
Replica of the Iron Duke at the National Railway Museum, York
David Ingham

Based on the success of the Firefly class, Daniel Gooch wanted to build an even more powerful and faster express locomotive. The driving wheels were increased from seven to eight feet and the largest possible boiler was installed in order to be able to take full advantage of the broad gauge. The wheel arrangement was still 2-2-2 and all wheels were mounted between the inner and outer frames. The cylinders were mounted between the inner frames.

“Great Western” in its original condition
“Great Western” in its original condition
Die Lokomotive, September 1937

The “Great Western” was completed in 1846 as the forerunner of the series. After just a short trial, the leading axle broke, which was attributed to the fact that the locomotive was too heavy to distribute the load over just three axles. The solution was to replace the leading axle with two axles that were also mounted in the frame. Although this made the locomotive heavier overall, the load on the driving axle fell. A further 29 series pieces were built in this form. The class was named “Iron Duke” after the first newly built machine and is said to have reached a top speed of 78 mph. The five-car express between London and Bristol is said to have averaged 68 mph on the 53 miles long section to Didcot.

“Great Western” with fixed leading axles
“Great Western” with fixed leading axles
Die Lokomotive, September 1937

In 1871 the “Great Britain”, “Prometheus” and “Estaffete” locomotives were converted to the Rover class. They received a larger boiler with higher pressure and a flat, elevated firebox instead of the previous haystack-shaped firebox. While the Iron Duke class locomotives were gradually phased out, their names were reused for 19 newly built Rover class examples, produced up to 1888.

The last engines of the Rover class did not have long lives, as broad gauge operations ceased in 1892. All pieces were then scrapped. It was not until 1985 that a working replica of the Iron Duke was built using parts from two Hunslet Austerity tank locos. It was not restored to service after her boiler life expired and now stands at the Didcot Railway Centre.

VariantGreat WesternIron DukeRover
General
Built18461847-18551871-1888
ManufacturerSwindon
Axle config2-2-2 (Jenny Lind) 4-2-2 (Single) 
Gauge7 ft 0 1/4 in (GWR broad gauge)
Dimensions and Weights
Wheelbase16 ft18 ft 8 in18 ft
Fixed wheelbase16 ft18 ft 8 in18 ft
Service weight64,961 lbs85,568 lbs93,408 lbs
Adhesive weight33,598 lbs31,802 lbs36,839 lbs
Total weight98,562 lbs
Axle load33,598 lbs31,802 lbs36,839 lbs
Water capacity4,323 us gal2,162 us gal3,603 us gal
Fuel capacitycoal
Power
Power sourcesteam
Estimated power300 hp (224 kW)400 hp (298 kW)600 hp (447 kW)
Optimal speed28 mph31 mph40 mph
Top speed80 mph
Starting effort6,885 lbf8,262 lbf9,639 lbf
Power Plant
Driver diameter96 in
Boiler pressure100 psi120 psi140 psi
Expansion typesimple
Cylinderstwo, 18 x 24 in
Boiler
Grate area22.6 sq ft25.5 sq ft24 sq ft
Firebox area151 sq ft131.8 sq ft137 sq ft
Tube heating area1,474 sq ft1,596.2 sq ft1,948 sq ft
Evaporative heating area1,625 sq ft1,728 sq ft2,085 sq ft
Total heating area1,625 sq ft1,728 sq ft2,085 sq ft
Calculated Values
steam locomotive
express
Daniel Gooch
last changed: 07/2022
Great Western Railway class 3031 “Achilles” / “Dean Single”
Great Britain | 1894 | 30 produced
Nr. 3046 “Lord of the Isles”
Nr. 3046 “Lord of the Isles”
Locomotive Magazine, January 1899

The Class 3031 of the Great Western Railway, also known as the “Dean Single”, was created from the conversion of 30 examples of the Class 3001, which had been built by William Dean in the 7 feet 1/4 inch broad gauge and were converted to standard gauge a short time later. Since an increase in power through a wider boiler was impossible with the standard gauge due to the limited space between the large wheels, the boiler was extended to the front. After the leading axle derailed in the middle of the box tunnel due to the increased weight, it was replaced with a bogie, resulting in the class 3031. Since the cylinders were located below the smoke box in class 3001, a special bogie had to be constructed. This could be pulled out after loosening four screws and slightly lifting the front part of the locomotive to ensure uncomplicated maintenance of the smoke box and cylinders.

No. 3050 “Royal Sovereign”
No. 3050 “Royal Sovereign”
J.R. Howden, The Boys' Book of Locomotives

First, two class 3001 locomotives were converted in March 1894, the remaining 28 were converted between June and December of the same year. A total of 50 more were factory built between 1894 and 1899. In use, the class 3031, like other locomotives with a 4-2-2 wheel arrangement, excelled with high sustained speeds. On May 9, 1904, a mail train was able to travel the 117 miles from Bristol to London-Paddington in just under 100 minutes for the first time, which corresponds to an average speed of around 70 mph. However, since one driven axle was soon no longer sufficient, they were decommissioned between 1908 and 1915. Today there is a replica of No. 3041 “The Queen”, which was completed in 1982.

General
Built1894-1899
ManufacturerSwindon
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase23 ft 6 in
Fixed wheelbase9 ft
Service weight109,760 lbs
Adhesive weight40,320 lbs
Total weight182,560 lbs
Axle load40,320 lbs
Water capacity4,323 us gal
Fuel capacitycoal
Power
Power sourcesteam
Estimated power725 hp (541 kW)
Optimal speed36 mph
Starting effort12,738 lbf
Power Plant
Driver diameter92.5 in
Boiler pressure160 psi
Expansion typesimple
Cylinderstwo, 19 x 24 in
Boiler
Grate area20.8 sq ft
Firebox area127 sq ft
Tube heating area1,434 sq ft
Evaporative heating area1,561 sq ft
Total heating area1,561 sq ft
Calculated Values
steam locomotive
express
William Dean
last changed: 02/2022
Midland classes 115 and 2601
Great Britain | 1896 | 25 produced
Colored side view of No. 116
Colored side view of No. 116
Locomotive Magazine, January 1898

After the Midland Railway had already procured 70 examples of express locomotives in the 4-2-2 wheel arrangement in the late 1880s, the era of express locomotives without a second coupled axle was already considered over. However, the Midland followed the strategy of using smaller locomotives, which were then supported by a second locomotive when required. Then, when steam-powered sanders were introduced, Samuel Waite Johnson developed another single express locomotive.

Inner and outer frames were used to safely transmit the forces of a powerful express locomotive to just one axle. Thus, the driven axle had four bearings and could easily withstand the forces of the internal cylinders. After five examples of the class 115 built in 1896 and 1897, another ten units were built in 1899.

Also in 1899, the class 2601 was presented, of which ten examples were built. The driving wheels were half an inch larger, the boiler pressure was increased from 170 to 180 psi, and the firebox was larger. In addition, the slide valves were replaced with piston valves. Instead of the previous three-axle tender, now a four-axle one was used.

Schematic drawing of class 2601
Schematic drawing of class 2601
Die Lokomotive, December 1904

The locomotives were basically used on main routes without significant gradients. There they typically hauled express trains weighing between 200 and 250 long tons and could reach speeds of 90 mph. Some of them were also used in front of trains with 350 long tons and proved their worth there, as long as there were no difficult adhesion conditions. Later, when they could no longer cope with the increased train weights, they were still used as pilot locomotives, sometimes even in front of coal trains. Their service life ended in the late twenties.

Variant1152601
General
Built1896-1897, 18991899
ManufacturerDerby
Axle config4-2-2 (Single) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase21 ft 11 in
Fixed wheelbase8 ft 9 in
Service weight105,560 lbs112,336 lbs
Adhesive weight41,440 lbs
Total weight197,400 lbs162,236 lbs
Axle load41,440 lbs
Water capacity4,203 us gal
Fuel capacity8,960 lbs (coal)
Power
Power sourcesteam
Estimated power750 hp (559 kW)800 hp (597 kW)
Optimal speed31 mph32 mph
Top speed90 mph
Starting effort15,361 lbf16,178 lbf
Power Plant
Driver diameter93 in93.5 in
Boiler pressure170 psi180 psi
Expansion typesimple
Cylinderstwo, 19 1/2 x 26 in
Boiler
Grate area21.3 sq ft24.5 sq ft
Firebox area128 sq ft147 sq ft
Tube heating area1,105 sq ft1,070 sq ft
Evaporative heating area1,233 sq ft1,217 sq ft
Total heating area1,233 sq ft1,217 sq ft
Calculated Values
steam locomotive
express
Samuel Waite Johnson
last changed: 06/2022
Philadelphia & Reading No. 385 and 378
später umgebaut zu class D-10a and D-10b
United States | 1895 | 2 produced
No. 378
No. 378
collection Taylor Rush

Superintendent L.B. Paxson of the Philadelphia & Reading was convinced in the mid-1890s that an express locomotive with one powered axle would still be sufficient to haul express trains at high speed. He was thinking in particular of some trains between Jersey City and Philadelphia that covered the 90 miles with a light load. When asked about the ideal wheel arrangement, the choice fell on 4-2-2, which was popular in Great Britain and was called “single” or “bicycle” there.

No. 385
No. 385
Railway and Locomotive Engineering, August 1895

A Wootten firebox with a grate of 75 square feet was installed in order to be able to produce a lot of steam at high speeds with the combustion of residues from the anthracite processing. This meant that it was designed as a Camelback locomotive with the driver's cab in the middle of the boiler. The steam dome sat behind the driver's cab on the firebox. The power was provided by a four-cylinder compound engine of the Vauclain type, in which a jointly cast high and low pressure cylinder were present on each side.

Schematic drawing after the rebuild as 4-4-0
Schematic drawing after the rebuild as 4-4-0
Die Lokomotive, July 1914

After the number 385 built in 1895, the almost identical number 378 followed in the following year. The locomotives ran the mentioned route including the intermediate stops at an average of 51.4 mph and ran very smoothly. The 385 is said to have even reached 120 mph for a short time. Even if the two locomotives easily transported trains of around 350 tons, the low adhesive weight was soon no longer sufficient.

Both examples were rebuilt in 1904 into locomotives with a 4-4-0 wheel arrangement, which differed from each other. One thing they had in common, however, was that both received a simple two-cylinder engine with 19 by 26-inch cylinders. The 385 became the D10-a class and retained its 84.25 inch coupled wheel diameter. It lost its combustion chamber during the rebuild and instead had a larger tubular heating surface. The 378, now class D10-b, had the coupled wheels downsized to 78.5 inches and still had a combustion chamber, but also had a slightly larger boiler overall.

Variantas builtrebuilt D-10arebuilt D-10b
General
Built1895-18961904
ManufacturerBaldwin
Axle config4-2-2 (Single) 4-4-0 (American) 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Wheelbase22 ft 9 in23 ft 6 1/2 in
Fixed wheelbase7 ft 6 in
Service weight115,000 lbs150,000 lbs154,050 lbs
Adhesive weight48,000 lbs98,625 lbs103,875 lbs
Total weight199,000 lbs290,000 lbs306,050 lbs
Axle load48,000 lbs49,315 lbs51,940 lbs
Water capacity4,000 us gal
Fuel capacity14,000 lbs (coal)
Power
Power sourcesteam
Estimated power1,425 hp (1,063 kW)1,500 hp (1,119 kW)1,575 hp (1,174 kW)
Optimal speed69 mph50 mph49 mph
Starting effort13,143 lbf18,939 lbf20,326 lbf
with start valve15,772 lbf
Power Plant
Driver diameter84.3 in78.5 in
Boiler pressure200 psi
Expansion typecompoundsimple
Cylindersfour, HP: 13 x 26 in
and LP: 22 x 26 in
two, 19 x 26 in
Boiler
Grate area76 sq ft
Firebox area173 sq ft137 sq ft211 sq ft
Tube heating area1,293 sq ft1,731 sq ft1,543.5 sq ft
Evaporative heating area1,466 sq ft1,868 sq ft1,754.5 sq ft
Total heating area1,466 sq ft1,868 sq ft1,754.5 sq ft
Calculated Values
steam locomotive
express
Vauclain compound
last changed: 07/2022
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  • Imperial (UK): Lengths in feet/inches, weights in long tons and volumes in imperial gallons
  • Imperial (US): Lengths in feet/inches, weights in pounds, and volumes in US gallons
  • Individual: Depends on the country of origin of each locomotive
Operator names

Here you can set the display of railway company names.

  • Short: Abbreviation or short form of the name
  • Standard: commonly used name, partially translated to English
  • Complete: full name in local language