South African Class 15CA 4-8-2


The South African Railways Class 15CA 4-8-2 of 1926 was a steam locomotive.
In 1926, the South African Railways placed 23 Class 15CA steam locomotives with a 4-8-2 Mountain type wheel arrangement in service. Another 61 engines were ordered and delivered from three manufacturers in 1929 and 1930.

Class 15C redesign

After the twelve Class 15C Big Bill Mountain type locomotives which were delivered by Baldwin Locomotive Works in 1925 had been in service a short while, it was discovered that the frames under the front of the firebox had a tendency to crack, necessitating heavy repairs.
To overcome this, a new modified design was prepared by Col F.R. Collins DSO, the Chief Mechanical Engineer of the South African Railways, for an almost identical locomotive but with the frames shortened to the front of the firebox and widened under the firebox by means of a bridle casting.

Manufacturers

The first batch of 23 of these redesigned locomotives were built for the SAR by the American Locomotive Company. They were delivered in 1926, numbered in the range from 2039 to 2059, 2072 and 2073, and designated Class 15CA. The "A" supposedly indicated the manufacturer ALCO rather than, as was usual SAR practice, a different version of an existing locomotive type.
The earlier Baldwin-built Class 15C was then reclassified to Class 15CB for no good reason, since the "B" merely indicated the manufacturer Baldwin and not, as was usual practice, a branchline locomotive.
Another 61 Class 15CA locomotives were acquired in four batches from three other manufacturers in 1929 and 1930. Like the 23 ALCO-built locomotives, all except the last batch were built with bore cylinders.
Apart from the redesigned frame under the firebox, these locomotives were very similar to the Class 15C in proportions and appearance. They also had Coale pop type safety valves, a Schmidt type superheater and a combustion chamber in the firebox, which was equipped with flexible side stays and water siphon arch tubes. Their coupled wheel axleboxes, crank pins and connecting rod big ends were grease lubricated. These engines used the same Type KT tenders with a coal capacity of and a water capacity of.

Modifications

Retyring

The locomotives were delivered with diameter coupled wheels and their boilers were set at an operating pressure of. All their coupled wheels were eventually retyred to a diameter and to compensate for the loss of tractive effort due to the larger diameter wheels, their operating boiler pressure was increased from by an adjustment of the setting of their safety valves. This modification enabled these mixed traffic locomotives to handle the fastest mainline passenger trains.
In addition, all those locomotives which had been built with bore cylinders had their cylinders reamed to a bore of.
When larger tyres were fitted to their coupled wheels, the old tyres were left in position and turned down on the wheel centres to serve as liners and the new tyres were then shrunk on over the liners. The leading coupled wheels, which had been flangeless as built, were flanged during the retyring. The practice of increasing the diameter of coupled wheels, wheel spacing and other considerations permitting, was begun by A.G. Watson during his term in office as CME and was continued by his successors. The reduction of tractive effort caused by the larger wheels was made up by increasing boiler pressure or by fitting larger cylinders or both, as required. This policy resulted in more mileage between heavy repairs, less cost-per-mile on repairs and locomotives capable of higher speeds.

Reboilering

During the early 1940s, three of the Class 15CB and Class 15CA locomotives were reboilered with new boilers numbered in the range from 9504 to 9506. These boilers were of similar dimensions as the originals but with a different tube arrangement. It was designed by Dr. M.M. Loubser, CME at the time. The reboilered locomotives were not reclassified.

Service

South African Railways

The Class 15CA locomotives were placed in service on the mainline between Cape Town and Kimberley but like the Class 15CB, they were later transferred to Bloemfontein. From here they worked throughout the Free State until they were eventually relocated to the Eastern Transvaal system. There they worked out of Pretoria to Pietersburg in the north and from there to Tzaneen in the east and Messina on the Rhodesian border in the north. Some also worked out of Witbank and Breyten.
In the early 1960s, a few joined the Class 15CB on the Natal North Coast line. Here they were used on, amongst others, the night and day passenger trains to and from Empangeni on the north coast line and on passenger trains to and from Kelso on the south coast line. In 1983, they all went from there to the Cape Northern system for use on the lines from Beaconsfield in Kimberley, working north to Mafeking and south to De Aar. Eventually nearly forty of them ended up as heavy shunters at Kaserne and Germiston in Johannesburg where they replaced the Class 12AR and Class S1.
15CA 2828 is now plinthed at the Gospel Express, Vinkrivier Station, R60, Robertson, is the Western Cape, South Africa. 2828 completes the 11 coaches stationed at Vink, as accommodation for the Gospel Express Christian Centre.

Industry

Three Class 15CA locomotives were sold into industrial service. Numbers 2807 and 2839 went to Dunn's Locomotive Works and were eventually sold to Rustenburg Platinum Mines. No. 2811 went to South Witbank Colliery as their no. 4.

Works numbers

The table lists the Class 15CA engine numbers, builders, years built and the builders' works numbers. The colour coding following the engine numbers refer to the three axle loadings of the different batches of the Class 15CA, as shown in the table of specifications.

SAR No.		Builder
Year
Works
No.
2039 ALCO192666986
2040 ALCO192666987
2041 ALCO192666988
2042 ALCO192666989
2043 ALCO192666990
2044 ALCO192666991
2045 ALCO192666992
2046 ALCO192666993
2047 ALCO192666994
2048 ALCO192666995
2049 ALCO192666996
2050 ALCO192666997
2051 ALCO192666998
2052 ALCO192666999
2053 ALCO192667000
2054 ALCO192667001
2055 ALCO192667002
2056 ALCO192667003
2057 ALCO192667004
2058 ALCO192667005
2059 ALCO192667006
2072 ALCO192667007
2073 ALCO192667008
2074 Baldwin192960828
2075 Baldwin192960829
2076 Baldwin192960830
2077 Baldwin192960831
2801 Breda19292236
2802 Breda19292237
2803 Breda19292238
2804 Breda19292239
2805 Breda19292240
2806 Breda19292241
2807 Breda19292242
2808 Breda19292243
2809 Breda19292244
2810 Breda19292245
2811 NBL192823774
2812 NBL192823775
2813 NBL192823776
2814 NBL192823777
2815 NBL192823778
2816 NBL192823779
2817 NBL192823780
2818 NBL192823781
2819 NBL192823782
2820 NBL192823783
2821 NBL192823784
2822 NBL192823785
2823 NBL192823786
2824 NBL192823787
2825 NBL192823788
2826 NBL192823789
2827 NBL192823790
2828 NBL192823791
2829 NBL192823792
2830 NBL192823793
2831 NBL192823794
2832 NBL192823795
2833 NBL192823796
2834 NBL192823797
2835 NBL192823798
2836 NBL192823799
2837 NBL192823800
2838 NBL192823801
2839 NBL192823802
2840 NBL192924008
2841 NBL192924009
2842 NBL192924010
2843 NBL192924011
2844 NBL192924012
2845 NBL192924013
2846 NBL192924014
2847 NBL192924015
2848 NBL192924016
2849 NBL192924017
2850 NBL192924018
2851 NBL192924019
2852 NBL192924020
2853 NBL192924021
2854 NBL192924022
2855 NBL192924023
2856 NBL192924024
2857 NBL192924025

Preservation

NumberWorks nmrTHF / PrivateLeaselend / OwnerCurrent LocationOutside South Africa?
2039ALCO 66986PrivateMISLPT Krugersdorp Locomotive Depot
2040ALCO 66987PrivateMISLPT Krugersdorp Locomotive Depot
2041ALCO 66988PrivateMISLPT Krugersdorp Locomotive Depot
2055ALCO 67005THFRustenburg
2056ALCO 67003THFReefsteamersGermiston Locomotive Depot
2077BAL 60831PrivateMISLPT Krugersdorp Locomotive Depot
2802BREDA 2237THFEsslenpark Railway College
2803BREDA 2238PrivateMISLPT Krugersdorp Locomotive Depot
2804BREDA 2239THFEsslenpark Railway College
2820NBL 23783PrivateMISLPT Krugersdorp Locomotive Depot
2825NBL 23788THFKrugersdorp Locomotive Depot
2828NBL 23791THFGospel ExpressVink
2833NBL 23796THFKrugersdorp Locomotive Depot
2836NBL 23799THFKrugersdorp Locomotive Depot
2850NBL 24018THFWonder Steam Trains
2853NBL 24021THFKrugersdorp Locomotive Depot

Illustration

The main picture shows Breda-built no. 2802, serving as school guard at Esselen Park, the Transnet School of Rail in Kaalfontein, Gauteng, on 21 September 2009.