South African type XM4 tender

The South African type XM4 tender was a steam locomotive tender.

South African type XM4 tender
Type XM4 tender on SAR Class MF
Type and origin
LocomotiveSAR Class MF
DesignerAmerican Locomotive Company
BuilderAmerican Locomotive Company
In service1911
Specifications
Configuration2-axle bogies
Gauge3 ft 6 in (1,067 mm) Cape gauge
BogiesDiamond frame
Wheel dia.30 in (762 mm)
Wheelbase17 ft 10 in (5,436 mm)
 • Bogie5 ft 10 in (1,778 mm)
Axle load12 LT 15 cwt (12,950 kg) average
 • Bogie25 LT 10 cwt (25,910 kg) average
Weight empty51,840 lb (23,510 kg)
Weight w/o51 LT (51,820 kg)
Fuel typeCoal
Fuel cap.10 LT (10.2 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 1629-1633

Type XM4 tenders entered service in November 1911, as tenders to the second batch of 2-6-6-2 Superheated Mallet type steam locomotives which were delivered to the Central South African Railways in that year. These locomotives were designated Class MF on the South African Railways in 1912.[1][2][3]

Manufacturer edit

Type XM4 tenders were built in 1911 by the American Locomotive Company (ALCO).[1][2][3]

In November 1911, the Central South African Railways (CSAR) placed a second batch of five 2-6-6-2 Mallet articulated compound steam locomotives in service, built by ALCO. These locomotives were designated Class MF on the South African Railways (SAR) in 1912. The Type XM4 tender entered service as tenders to these five engines.[1][2][3]

Characteristics edit

 
Diamond Frame bogie

As built, the tender had a coal capacity of 10 long tons (10.2 tonnes) and a water capacity of 4,000 imperial gallons (18,200 litres), with an average maximum axle load of 12 long tons 15 hundredweight (12,950 kilograms). It rode on diamond frame bogies with a 5 feet 10 inches (1,778 millimetres) wheelbase per bogie.[2][3]

Locomotive edit

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.[3][4]

Only the second batch of five Class MF locomotives were delivered new with Type XM4 tenders. They were numbered in the range from 1629 to 1633, directly onto the SAR roster, marking the introduction of the SAR renumbering scheme under the Union programme.[2][3][4][5]

Classification letters edit

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 can be coupled. The "X_" tenders could be used with the locomotive classes as shown.[1][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]

References edit

  1. ^ a b c d Holland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. pp. 16–19. ISBN 978-0-7153-5427-8.
  2. ^ a b c d e 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. ^ a b 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)
  5. ^ Espitalier, T.J.; Day, W.A.J. (1945). The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued). South African Railways and Harbours Magazine, May 1945. p. 347.