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The “Consolidation”: its Story and Development

The 2-8-0 Which Revolutionized the Movement of Freight and Heavy Mixed Traffic



THE FIRST “CONSOLIDATION” (2-8-0) BUILT IN 1866. In working order the engine scaled 90,000 lb; of this amount 80,000 lb, distributed over the, 48-inch coupled drivers, were available for adhesion. The feed-water pump was operated from the crank-pin of the rear driving axle.

IN 1866 the Lehigh and Mahanoy railways combined to become part of what is now known as the Lehigh Valley Railroad. The first year of operation under the amended title was commemorated by the introduction of a new type of locomotive, with a leading two-wheeled pony truck and four pairs of coupled wheels giving the arrangement 2-8-0. It was designed by Alexander Mitchell, at that time master-mechanic of the Delano shops, and afterwards superintendent of the Wyoming Division of the road, for the haulage of the heavy coal traffic, and was built at the Baldwin Works. To commemorate the fusion of the two railways this locomotive was christened “Consolidation”. It proved so conspicuously successful in the duty for which it was designed as to undergo extensive development, and sustained recognition, not only in the land of its birth, but in other countries where similar freight traffic conditions prevail, by the extension of the name of the engine to the family of which it was the progenitor.

“Consolidation” had cylinders 20 by 26 inches, and a boiler 26 feet 2 inches in length by 59 inches in diameter. The driving wheels were 48 inches in diameter and coupled, the length of the main rods being 115 inches. The first three driving wheels were spaced 56 inches apart, centre to centre, but the distance between the third and fourth pairs was 62 inches. It was equipped with a feed-water pump operated from the crank-pin of the rear driving axle, while the spring-rigging arrangement comprised elliptic springs, placed over each driving box. The Bissell pony truck in front was equalized with the first pair of driving wheels. The weight of the engine in working order was 90,000 lb; of this amount 80,000 lb were imposed upon the driving wheels for adhesion.

The locomotive was introduced to move the traffic over a heavy section of the road, rising 133 feet per mile, which superseded the abrupt inclines on the hill-sides known as the Mahanoy Planes. There were two of these inclines, one at Penn Haven Junction and the other near Frackville. These planes were approximately 850 feet in length, and in that distance the latter rose 600 feet. The first-named was built about 1853, and the whole of the coal from the Hazleton region was moved over the Mahanoy road, down the plane to the canal boats moored at the foot. The loaded cars were lowered down the incline by means of a cable which was connected to the empty cars moving up the opposite track, so that some of the gravitational energy of the former was put to useful account. The last shipments of coal over these planes were made about 1868. Then they were dismantled and the tracks torn up, though the rights of way are still visible on the hill-side.

The Lehigh Valley Railroad, from the success of the “Consolidation”, has persistently supported this type, and in 1898 introduced what was one of the most powerful of this class, up to that time, for the movement of freight trains over the Wilkes-barre Mountain, where the grade is 61 feet per mile for a distance of about 20 miles. It was a Baldwin Vauclain Compound with high- and low-pressure cylinders of 18 and 30 inches respectively in diameter, by 30-inches stroke; a straight boiler 80 inches in diameter with a working steam pressure of 200 lb; a total heating surface of 4,106 square feet; and grate area of 90 square feet.


“CONSOLIDATION” LOCOMOTIVE, BUILT FOR THE LEHIGH VALLEY RAILROAD, 1898. The engine was fitted with a “Mother Hubbard” cab, and was guaranteed to move a train, weighing 1,000 tons, over the mountains at an average speed of 17 miles per hour. The driver was isolated in the cab astride the boiler, while the fireman worked on the foot-plate.

The driving wheels were 55 inches in diameter. The tender, mounted on two four-wheeled trucks, carried 7,000 gallons of water and 8 tons of fuel. The total weight of the unit - 55 feet of inch in length overall - was 365,000 lb, and of this amount the engine represented 225,000, with 202,200 lb upon the drivers; the tractive force was 46,400 lb. It was guaranteed to move a train weighing 1,000 tons, exclusive of engine and tender, over the mountain at an average speed of 17 miles per hour, and so satisfactorily served this purpose that fourteen similar units were ordered.

In this locomotive the cab was moved from the foot-plate to a position astride the boiler over the driving wheels after the manner introduced in 1877 by John E. Wootten with the boiler bearing his name. The fireman maintained his familiar position upon the deck of the tender. Originally he was completely exposed to the weather, but in this Lehigh Valley Railroad “Consolidation” he was protected by a substantial shield secured to the back-head of the boiler, which became the general practice until the driving cab was returned ultimately to the foot-plate.

This arrangement led to the ascription of “Mother Hubbards” to locomotives of this design. From the driver’s point of view the situation of the cab was far from congenial. Riding was uncomfortable, while in summer the heat was wellnigh intolerable. Another objection was the possibility of the driver suddenly being stricken down without his companion on the foot-plate becoming promptly aware of the fact; similarly, of course, the driver would be ignorant of any mishap befalling his colleague at the rear. Finally, in the event of a side-rod breaking there was the risk of it piercing the floor of the cab.


THE FIRST BRITISH LOCOMOTIVE OF THE “CONSOLIDATION” (2-8-0) TYPE, 1903. It was built at Swindon by the Great Western railway for the heavy mineral traffic of South Wales.

Although the “Consolidation ” type was introduced upon the American railways as far back as 1866, it was not until thirty-seven years later that it made its debut upon the British roads. The movement was pioneered by the Great Western Railway, through the enterprise of Mr. Churchward, in 1903, with an experimental engine having the road number “97”, for the haulage of the heavy mineral traffic of South Wales. This had cylinders 18 by 30 inches and driving wheels 55½ inches in diameter. The coned boiler barrel measured 14 feet 10 inches in length by 66 inches, tapering to 585 inches in outside diameter, with a heating surface of 1,988·65 square feet, which, with that of the fire-box, 154·26 square feet, brought the total heating surface to 2,142·91 square feet. The grate area was 27·1 square feet; while steam was raised to 200 lb per square inch. In this engine the total weight distributed over the eight coupled wheels was 138,656 lb.

Two years later the “Consolidation” appeared upon the London and North Western Railway. These, however, were not specially designed but converted locomotives - Mr. Webb, the chief mechanical engineer, took some of his standard 0-8-0 freight four-cylinder compound engines and fitted them with a pony truck. In this process of transformation the engines were equipped with larger boilers. For some time the Great Western and London and North Western Railways were the only two roads in Great Britain to champion the cause of the “Consolidation”.

The development of the heavy mineral traffic of the Great Western Railway upon the South Wales division demanded more powerful locomotives, and this necessity was met, in the first instance, by “Consolidation” tanks with cylinders 18½ by 30 inches, coned boiler barrel 11 feet in length by 66 inches maximum diameter pressed to 200 lb per square inch, and coupled wheels 55½ inches in diameter. The heating surface, including superheater, aggregates 1,670·15 square feet, and the draw-bar-pull is 31,450 lb. These tanks comprise what is known as the “42” class.


GREAT WESTERN “CONSOLIDATION” (2-8-0) TYPE, BUILT 1919. This locomotive, the original of the “4700” class built at Swindon for heavy express “mixed” traffic, is the first British “Consolidation” to be furnished with 68-inch coupled wheels.

These were followed, in 1919, by what is known as the “4,700” class of “Consolidation” expressly designed for heavy express “mixed” traffic, and are notable as being the first of the 2-8-0 type in Great Britain to be fitted with coupled wheels 68 inches in diameter. They have cylinders 19 inches in diameter by 30-inches stroke, working at a pressure of 225 lb per square inch, and were designed to admit of a larger boiler, the coned barrel of which measures 14 feet 10 inches in length by 72 inches external diameter at the fire-box end, tapering to 66 inches at the front. The total heating surface, including the superheater, is 2,521·7 square feet, while the tractive effort is 30,460 lb.

Probably no type of locomotive was so extensively employed during the Great War as the 2-8-0. Indeed, it would be no exaggeration to say that “General Consolidation” played a deciding part in the defeat of Germany. It certainly dominated the railway transport situation in France. The orders for motive power for the conduct of the campaign rose to unprecedented proportions. The North British Locomotive Company, alone, turned out 774 locomotives from their Glasgow shops for the war area in Flanders.

The most conspicuous type was the “Consolidation”, and the various designs then in service upon the British railways were fully considered for the selection of one for mass production. Decision fell upon that in service upon the Great Central, and this became officially known as “The Great Central Class”.

These had cylinders 21 by 26 inches working at 180 lb of steam per square inch, with driving wheels 56 inches in diameter; total heating surface, including superheater, 1,756 square feet; grate area 26·25 square feet; and six-wheel tenders, carrying 4,000 gallons of water and 315 cubic feet of coal. In running order they weighed 274,736 lb; of this amount the engine accounted for 165,424 lb, with 150,416 lb available for adhesion, and a tractive effort, at 75 per cent, of the boiler pressure, of 27,640 lb.


THE “GREAT CENTRAL” CLASS OF “CONSOLIDATION”. The North British Locomotive Company built 369 of this class to the order of the Ministry of Munitions for service in France, and 215 other “Consolidations” to the designs of the French Railways.

The Scottish manufacturers supplied 369 locomotives of this type to the British authorities for service in France, and also 215 “Consolidations” to French design, out of a total of 380 locomotives built for the French Government. The balance of this order comprised 45 locomotives of the “Pacific” type; 40 “Ten-wheelers”; and 80 “Mikado” tanks.

The British Government also placed an order with the Baldwin Locomotive Works of Philadelphia for the construction of 465 standard gauge locomotives. Of this total 150 were “Consolidations”, with cylinders 21 inches in diameter by 28 inches stroke, and scaling 162,500 lb in working order. The balance of the order was made up with 0-4-0, 0-6-0 and 2-6-2 tanks, and six-wheels-coupled, or “Ten-wheelers”.

The dispatch of the American army to Europe forced the American construction of locomotives to its highest level. The first order placed with the Baldwin Company was for the supply of 150 of the “Consolidation” type, similar to those built for the British Government, but fitted with superheaters. These became colloquially, and officially, known as the “Pershing Engines”, after the commander-in-chief of the American forces. The order was placed on July 17, 1917, and the first engine was delivered on August 10, or twenty-four days later, while the last of the consignment left the Philadelphia shops on October 1 following. These locomotives gave such excellent all-round service as to lead to the placing of further successive and larger orders. At the cessation of hostilities the Baldwin Company had intensified manufacture to such a degree as to be able to build 300 locomotives a month - ten a day!

You can read more on “From the Atlantic to the Pacific”, “Giant American Locomotives” and “The Mountain Type” on this website.