In 1904 the Cape Government Railways

Cape Government Railways

The Cape Government Railways was the government-owned railway operator in the Cape Colony from 1874 until the creation of the South African Railways in 1910.-Private railways:...

 placed four Karoo Class 4-6-2

4-6-2

4-6-2, in the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles , six powered and coupled driving wheels on three axles, and two trailing wheels on one axle .These locomotives are also known as Pacifics...

 Pacific passenger steam locomotive

Steam locomotive

A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

s in service. In 1912, when they were assimilated into the South African Railways, they were renumbered and classified as Class 5B.

Manufacturer

Following on the success of the first two Karoo Class

South African Class 5A 4-6-2

In 1903 the Cape Government Railways placed two Karoo Class steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 5A....

 locomotives of the Cape Government Railways (CGR), a further four were ordered from Beyer, Peacock and Company

Beyer, Peacock and Company

Beyer, Peacock and Company was an English railway Locomotive manufacturer with a factory in Gorton, Manchester. Founded by Charles Beyer and Richard Peacock, it traded from 1854 until 1966...

 in 1904 and delivered in that same year. They were modified slightly in view of the experience gained with the original two Karoo locomotives.

They were numbered 905 to 908 and, like the previous two locomotives, they were also not allocated class numbers by the CGR. Instead they were also known as the Karoo Class, from the region of the Western System where they were designed to work.

Class 5 sub-classes

When these four locomotives were assimilated into the newly established South African Railways (SAR) in 1912, they were renumbered 723 to 726 and reclassified to Class 5B. The rest of the CGR’s Karoo Class locomotives were grouped into two more sub-classes by the SAR.

Watson Standard boilers

In the 1930s many serving locomotives were reboilered with a standard boiler type designed by then Chief Mechanical Engineer (CME) A.G. Watson as part of his standardisation policy. Such Watson Standard reboilered locomotives were reclassified by adding an "R" suffix to their classification.

Only one of the Class 5B locomotives, number 725, was eventually reboilered with a Watson Standard no. 1 boiler and reclassified to Class 5BR.

Piston valves

Watson also equipped the Class 5B and Class 5BR with piston valve cylinders. On the Class 5B this became necessary when they were equipped with superheaters, but their classification remained unchanged after this modification. The Class 5BR was equipped with superheating at the time that it was reboilered with a Watson Standard boiler and reclassified.

Service

In service the Class 5B locomotives performed excellently. CGR Chief Locomotive Superintendent H.M. Beatty’s annual report for 1905 stated that they collectively ran 171000 miles (275,197.1 km) without a failure of any description.

They spent a large part of their working lives in the Karoo

Karoo

The Karoo is a semi-desert region of South Africa. It has two main sub-regions - the Great Karoo in the north and the Little Karoo in the south. The 'High' Karoo is one of the distinct physiographic provinces of the larger South African Platform division.-Great Karoo:The Great Karoo has an area of...

 working between Beaufort West

Beaufort West

Beaufort West is a town in the Western Cape province in South Africa. It is the largest town in the arid Great Karoo region, and forms part of the Beaufort West Local Municipality, with 37 000 inhabitants in 2001....

 and De Aar, until they were displaced by larger locomotives and assigned to the Paardeneiland shed in Cape Town

Cape Town

Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

. Some remained in service around Cape Town for many years and became familiar sights on the Strand and Stellenbosch suburban trains, until the last locomotive of this Class was withdrawn by 1969.

Gallery

The main picture shows CGR Karoo Class 905, later SAR Class 5B 723, as depicted on a CGR post card.

See also

• South African Class 5 4-6-2
  South African Class 5 4-6-2
  In 1912 four Enlarged Karoo Class 4-6-2 Pacific passenger steam locomotives that had been ordered by the Cape Government Railways the year before, were placed in service by the newly established South African Railways...
  
  
• South African Class 5A 4-6-2
  South African Class 5A 4-6-2
  In 1903 the Cape Government Railways placed two Karoo Class steam locomotives with a 4-6-2 Pacific wheel arrangement in passenger service. In 1912, when they were assimilated into the South African Railways, they were renumbered and reclassified to Class 5A....
  
  
• South African Class Exp 1 4-6-2
  South African Class Exp 1 4-6-2
  In 1907 the Cape Government Railways placed a single experimental three cylinder compound steam locomotive with a 4-6-2 Pacific wheel arrangement in service, based on the second series of the Karoo Class locomotives...
  
  
• Tender locomotive numbering and classification
• Watson Standard boilers
• The 4-6-2 "Pacific"
• List of South African locomotive classes