South African type XM tender

The South African type XM tender was a steam locomotive tender.

South African type XM tender
Type XM tender on Class 4A
Type and origin
LocomotiveClass 4A
DesignerCape Government Railways
(H.M. Beatty)
BuilderNorth British Locomotive Company
In service1913-1914
Specifications
Configuration2-axle bogies
Gauge3 ft 6 in (1,067 mm) Cape gauge
Length25 ft 1 in (7,645 mm)
Wheel dia.33+12 in (851 mm) as built
34 in (864 mm) retyred
Wheelbase16 ft 1 in (4,902 mm)
 • Bogie4 ft 7 in (1,397 mm)
Axle load11 LT 18 cwt (12,090 kg)
 • Front bogie23 LT 9 cwt (23,830 kg)
 • Rear bogie23 LT 16 cwt (24,180 kg)
Weight empty47,920 lb (21,740 kg)
Weight w/o47 LT 5 cwt (48,010 kg)
Fuel typeCoal
Fuel cap.8 LT (8.1 t)
Water cap.4,000 imp gal (18,200 L)
StokingManual
CouplersDrawbar & Johnston link-and-pin
Drawbar & AAR knuckle (1930s)
Career
OperatorsSouth African Railways
NumbersSAR 1551-1560

Ten Type XM tenders entered service in 1913, as tenders to the Class 4A 4-8-2 Mountain type steam locomotives which were acquired by the South African Railways in that year.[1][2][3]

Manufacturer

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Type XM tenders were built by the North British Locomotive Company in 1913.[1][2][3]

The original Class 4 Mountain type locomotive was designed as a heavy mixed traffic locomotive by H.M. Beatty, the last Chief Locomotive Superintendent of the Cape Government Railways (CGR), at the Salt River shops. Soon after the South African Railways (SAR) locomotive renumbering project was implemented in 1912, an order was placed with North British for a further ten locomotives of this type. They were delivered late in 1913 and were designated Class 4A. The Type XM entered service as tenders to these engines.[1][2][3]

Characteristics

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The Type XM tender had a coal capacity of 8 long tons (8.1 tonnes), a water capacity of 4,000 imperial gallons (18,200 litres) and a maximum axle loading of 11 long tons 18 hundredweight (12,090 kilograms).[2][3]

Locomotive

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In the SAR years, tenders were numbered for the engines they were delivered with. In most cases, an oval number plate, bearing the engine number and often also the tender type, would be attached to the rear end of the tender. Only the ten Class 4A locomotives were delivered new with Type XM tenders, numbered in the SAR number range from 1551 to 1560.[2][3][4]

Classification letters

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Since many tender types are interchangeable between different locomotive classes and types, a tender classification system was adopted by the SAR. The first letter of the tender type indicates the classes of engines to which it could be coupled. The "X_" tenders could be used with the locomotive classes as shown.[3]

The second letter indicates the tender's water capacity. The "_M" tenders had a capacity of 4,000 imperial gallons (18,200 litres; 4,800 US gallons).[3]

A number, when added after the letter code, usually indicates differences between similar tender types, such as function, wheelbase or coal bunker capacity.[3]

Modification

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Pictures of most of these locomotives in service show them with a modified tender with built-up sides to the coal bunker to increase the coal capacity. Early versions of the built-up coal bunker sides were in the form of a slatted open-top cage, made of rectangular steel rods. Later versions were constructed of sheet-metal.[2][3]

Illustration

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References

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  1. ^ a b c Holland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. pp. 12–13, 22–23. ISBN 978-0-7153-5427-8.
  2. ^ a b c d e f South African Railways & Harbours/Suid Afrikaanse Spoorweë en Hawens (15 Aug 1941). Locomotive Diagram Book/Lokomotiefdiagramboek, 3'6" Gauge/Spoorwydte. SAR/SAS Mechanical Department/Werktuigkundige Dept. Drawing Office/Tekenkantoor, Pretoria. p. 43.
  3. ^ a b c d e f g h i South African Railways & Harbours/Suid Afrikaanse Spoorweë en Hawens (15 Aug 1941). Locomotive Diagram Book/Lokomotiefdiagramboek, 2'0" & 3'6" Gauge/Spoorwydte, Steam Locomotives/Stoomlokomotiewe. SAR/SAS Mechanical Department/Werktuigkundige Dept. Drawing Office/Tekenkantoor, Pretoria. pp. 6a-7a, 43.
  4. ^ Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer's Office, Pretoria, January 1912 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)