South African Class 24 2-8-4

South African Class 24 2-8-4
3655 City of Cape Town leaving Monument station, 8 August 2010
Type and origin
Power typeSteam
DesignerSouth African Railways
(Dr. M.M. Loubser)
BuilderNorth British Locomotive Company
Order numberL976
Serial number26313-26412
ModelClass 24
Build date1949-1950
Total produced100
Specifications
Configuration:
  Whyte2-8-4 (Berkshire)
  UIC1′D2′h2
Driver3rd coupled axle
Gauge3 ft 6 in (1,067 mm) Cape gauge
Leading dia.30 in (762 mm)
Coupled dia.51 in (1,295 mm)
Trailing dia.30 in (762 mm)
Tender wheels34 in (864 mm)
Minimum curve300 ft (91 m)
Wheelbase65 ft 3 in (19,888 mm)
  Engine31 ft (9,449 mm)
  Coupled13 ft 6 in (4,115 mm)
  Trailing4 ft 6 in (1,372 mm)
  Tender24 ft 7+14 in (7,499 mm)
  Tender bogie8 ft 8 in (2,642 mm)
Length:
  Over couplers74 ft 9+14 in (22,790 mm)
Height12 ft 10+78 in (3,934 mm)
Frame typeCast
Axle load11 LT 10 cwt (11,680 kg)
  Leading8 LT (8,128 kg)
  1st coupled11 LT (11,180 kg)
  2nd coupled11 LT 10 cwt (11,680 kg)
  3rd coupled11 LT 9 cwt (11,630 kg)
  4th coupled11 LT 5 cwt (11,430 kg)
  Trailing10 LT 2 cwt (10,260 kg) leading
9 LT 12 cwt (9,754 kg) trailing
  Tender bogieBogie 1: 28 LT 1 cwt (28,500 kg)
Bogie 2: 28 LT 10 cwt (28,960 kg)
  Tender axle9 LT 10 cwt (9,652 kg)
Adhesive weight45 LT 4 cwt (45,930 kg)
Loco weight72 LT 18 cwt (74,070 kg)
Tender weight56 LT 11 cwt (57,460 kg)
Total weight129 LT 9 cwt (131,500 kg)
Tender typeMY (Buckeye 3-axle bogies)
Fuel typeCoal
Fuel capacity9 LT (9.1 t)
Water cap.4,520 imp gal (20,500 L)
Firebox:
  TypeRound-top
  Grate area36 sq ft (3.3 m2)
Boiler:
  ModelWatson Standard no. 1
  Pitch8 ft (2,438 mm)
  Diameter5 ft (1,524 mm)
  Tube plates17 ft 9 in (5,410 mm) steel
17 ft 8+58 in (5,401 mm) copper
  Small tubes76: 2+12 in (64 mm)
  Large tubes24: 5+12 in (140 mm)
Boiler pressure200 psi (1,379 kPa)
Safety valveRoss-pop
Heating surface:
  Firebox123 sq ft (11.4 m2)
  Tubes1,497 sq ft (139.1 m2)
  Arch tubes16 sq ft (1.5 m2)
  Total surface1,636 sq ft (152.0 m2)
Superheater:
  Heating area380 sq ft (35 m2)
CylindersTwo
Cylinder size19 in (483 mm) bore
26 in (660 mm) stroke
Valve gearWalschaerts
Valve typePiston
Loco brakeVacuum
CouplersAAR knuckle
Performance figures
Tractive effort27,600 lbf (123 kN) @ 75%
Career
OperatorsSouth African Railways
ClassClass 24
Number in class100
Numbers3601-3700
Delivered1949-1950
First run1949
Withdrawn1980s

The South African Railways Class 24 2-8-4 of 1949 is a steam locomotive.

In 1949 and 1950, the South African Railways placed 100 Class 24 branch line steam locomotives with a 2-8-4 Berkshire type wheel arrangement in service.