Victorian Railways Dd class

The D^D class was a passenger and mixed traffic steam locomotive that ran on Victorian Railways from 1902 to 1974. Originally introduced on mainline express passenger services, they were quickly superseded by the much larger A² class and were relegated to secondary and branch line passenger and goods service, where they gave excellent service for the next fifty years. The D^D design was adapted into a 4-6-2T tank locomotive for suburban passenger use, the D^DE class. They were the most numerous locomotive class on the VR, with a total of 261 D^D and 58 locomotives built.

History

By 1900, Victoria's express passenger locomotive fleet was almost exclusively made up of 4-4-0 designs of the Old A, New A, and the most recent AA class. These locomotives reflected contemporary British locomotive practice, in no small part due to the Victorian Government having appointed, in 1884, a Midland Railway manager, Richard Speight, as its first Chief Railways Commissioner. The commissioners then asked British locomotive engineer Edward Jeffreys to design five standard types of locos, in partnership with the British locomotive manufacturer.
At the turn of the century, in what marked a major shift in policy, the recently appointed VR Commissioner, John Mathieson, set up a Locomotive Design Section for in-house development of future motive power. The D^D class locomotives were the first product of this exercise. A 4-6-0 design equipped with 5 ft 1 in driving wheels, saturated steam boiler and Belpaire firebox, the D^D reflected the considerable talent of VR's design team, which included ex-Beyer, Peacock & Company recruit Eugene Siepen, future VR Chief Mechanical Engineer Alfred Smith, and Rolling Stock Branch manager Thomas Woodroffe.

Production

The first D^D was number 560, constructed at the Victorian Railways' Newport Workshops and entering service in 1902. It was followed by engines 582 to 700, evens only, all constructed at Newport with the exception of 602, 604, 606, 608, 610, 632 and 634. These seven engines were notable as the last locomotives to be built by Ballarat's Phoenix Foundry, which had been the main supplier of locomotives to the VR for over thirty years. That was because the conservative Irvine government sought to reduce the costs of locomotive construction, and Newport Workshops was asked to tender for the construction of the D^D class locomotives. A fierce tender war between Newport and Phoenix eventually resulted in a Royal Commission, which found that Newport could produce a locomotive for £3,364, some £497 cheaper than the Phoenix Foundry. Phoenix produced just seven D^D locomotives and received no further orders, going into voluntary liquidation a year later.
Engines 702 to 796, again evens only, were delivered as tank engines of the class up to the end of 1910. By this point the odds/evens locomotive numbering scheme had been abandoned, so the last nine of the batch were delivered as 701-717 to start filling gaps.
As part of the competitive tendering process, in early 1912 contracts were signed with each of Beyer, Peacock & Company of Manchester, England, Baldwin Locomotive Works of the US, Walkers Limited of Maryborough, Queensland and Austral Otis, to compare against the cost of building engines at Newport Workshops. Ritchie Brothers of Sydney had also tendered but failed to win any of the orders. The contracts were for 20 engines each, with rights to a 20-engine extension and the possibility of up to a total of 100 engines. Respectively, Beyer, Peacock & Company delivered engines 531-569, Baldwin delivered 571-609 and Newport 611-649 in 1912. The following year saw Walkers delivered 651-689 while Newport supplied tank engines 721-749. Austral Otis encountered difficulties and withdrew from the contract in November 1912, leading to that contract being re-offered.
From 1914 newly delivered engines were consecutively numbered. Between 1914 and 1919 Newport delivered three batches of 20 engines each, numbered 873-912, 943-962 and 1013-1032, at a rate of 20 per year except the final two, delivered in 1918 and 1919 respectively.
The firm Thompsons & Co successfully won the contract for the 20 engines not being constructed by Austral Otis, and these were delivered from the end of 1914 numbered 893-912. A repeat order was placed in 1916 with deliveries of 963-982, and work had started on a further 20 engines when pressures of World War I led to the firm abandoning the remainder of the D^D contract extensions. The parts already constructed were forwarded to Victorian Railways workshops, initially with five each being built at Bendigo and Ballarat, and the next ten were split between Newport, Bendigo and Ballarat. These three workshops turned out virtually all subsequent locomotives for the Victorian railway system until the post-war era.

Regular service

D^D class locomotives were initially assigned to hauling the Adelaide Express over the steep gradients between Melbourne and Ballarat, but were soon seen on mainline passenger services on a number of lines.
The first years of the 20th century saw on the VR a considerable increase in both the amount of traffic and the size and weight of rolling stock being hauled. In 1907, the D^D class was supplanted by the much larger and more powerful A² class on principal mainline services. However, with their light axle load, they were quickly reassigned to the VR's branchline network, where they became a fixture for the next fifty years.
From July until September 1918, 1032 was loaned to the South Australian Railways for trails against a Rx class operating from Adelaide to Murray Bridge and Victor Harbor.

Commissioner's engines

With their light axle load and express passenger speed, the D^D was also an ideal choice as motive power for the Victorian Railways Commissioner's train. In January 1917, Commissioners' locomotive No. 100, a 2-4-0 built in 1872, was scrapped and replaced with the brand new D^D 980 from Thompsons Foundry in Castlemaine. It was later renumbered D^D 718, D^D 600 and D¹ 600, until March 1937 when it was placed into normal service as D¹ 576, operating until 1959. There is photographic evidence of D¹ 600 as Commissioners' Engine throughout the 1930s in the K.V. Scott collection. The new Commissioners engine from 1937 was D³ 683, specially fitted with an electric headlight and in August 1950 it was replaced by D³ 639. 639 herself was withdrawn in July 1956 and replaced with D³ 658, however 639's numbers were transferred to 658. D³ 639 was replaced by new 40 M.P.H, Clyde EMD diesel-electric Y 123 in January 1964. In August 1968 new diesel-electric Y 175 geared for 60 M.P.H. running took over until the Commissioners' Train was discontinued about 1979/80. In 1983 new Chief General Manager Mr. John Hearsch reinstated the Inspection Train with Clyde diesel-electric T 410. The Inspection train was discontinued after Hearsch left for Queensland Rail circa 1991.

D^D_E tank engine

The expansion of Melbourne's population into new suburbs early in the 20th century, and the delay of the suburban electrification project, saw the need for faster and more powerful steam locomotives for the suburban rail network. In 1908, the basic design of the D^D was adapted to create 4-6-2T tank locomotives, classed. They were put to work on longer and hillier suburban routes such as the Dandenong, Frankston, Upper Ferntree Gully, Williamstown, Werribee, Lilydale, Darling and Kew railway lines. A total of 58 were built between 1908 and 1913.
With electrification of the suburban network already on the drawing board, the was designed for easy conversion to D^D tender engines in the event of electrification making them redundant. However, only two were modified in that way. Ten were scrapped in 1924, followed by another four in 1925, and 704 was sold to the State Electricity Commission of Victoria. The remaining locomotives remained in service on non-electrified outer suburban routes or found new roles as suburban goods locomotives or shunters. Some were allotted to Ballarat to work the short branch line to Newlyn.

Design improvements

During the construction of the D^D class, a number of changes were made. The first locomotives built featured low running plates with splashers over the driving wheels and a narrow cab. However, after 26 such examples were built the design was altered with high running plates mounted above the driving wheels and a more comfortable full-width pressed metal cab of Canadian design, a feature incorporated at the request of Victorian Railways Chief Commissioner and former Canadian Pacific Transportation Manager Thomas Tait. These became hallmarks of all subsequent VR steam locomotive designs.
Although the Dd was considered to be a successful design, it had a key shortcoming in that its boiler performance was not sufficient for the traffic demands being placed on it. In 1914, an experimental superheater was fitted to D^D 882 and was found to be very successful. Both D^D and A² designs were modified with superheated boilers. Superheaters were also fitted to three of the locomotives. Further D^D locomotives were also built with 19 in. diameter cylinders in place of the original 18 in. cylinders.
In 1923–4, D^D 1022 was experimentally fitted with pulverised brown coal burning equipment.

Reclassing: D¹, D² and D⁴ class

In 1922 a complex renumbering and reclassing of VR locomotives saw the D^D class split into two subclasses, the D¹ class and the D² class.
With the introduction of a further D³ class in 1929, the tank locomotives were reclassified as D⁴ class in 1929.