South African Class 19 4-8-2

South African Class 19 & 19R 4-8-2

No. 1369 plinthed in Breyten, 11 June 2005

Type and origin ♠ Class 19 as built with a round-topped firebox ♥ Class 19R rebuilt with a Watson Standard boiler Power type Steam Designer South African Railways (Col F.R. Collins DSO) Builder Berliner Maschinenbau Serial number 9279-9282 Model Class 19 Build date 1928 Total produced 4

Specifications Configuration 4-8-2 (Mountain) Driver 2nd coupled axle Gauge 3 ft 6 in (1,067 mm) Cape gauge Leading dia. 28 1⁄2 in (724 mm) Coupled dia. 54 in (1,372 mm) Trailing dia. 33 in (838 mm) Tender wheels 34 in (864 mm) Wheelbase 58 ft 7 3⁄4 in (17,875 mm)  • Engine 32 ft 2 in (9,804 mm)  • Leading 6 ft 2 in (1,880 mm)  • Coupled 14 ft 5 in (4,394 mm)  • Tender 16 ft 9 in (5,105 mm)  • Tender bogie 4 ft 7 in (1,397 mm) Wheel spacing (Asymmetrical) 1-2: 4 ft 10 in (1,473 mm) 2-3: 4 ft 9 in (1,448 mm) 3-4: 4 ft 10 in (1,473 mm) Length: ​  • Over couplers 67 ft 6 1⁄2 in (20,587 mm) Height ♠ 12 ft 10 in (3,912 mm) ♥ 12 ft 10 7⁄8 in (3,934 mm) Frame type Bar Axle load ♠ 13 LT 9 cwt (13,670 kg) ♥ 12 LT 19 cwt (13,160 kg)  • Leading ♠ 14 LT 7 cwt (14,580 kg) ♥ 13 LT 18 cwt (14,120 kg)  • 1st coupled ♠ 13 LT 3 cwt (13,360 kg) ♥ 12 LT 15 cwt (12,950 kg)  • 2nd coupled ♠ 13 LT 1 cwt (13,260 kg) ♥ 12 LT 12 cwt (12,800 kg)  • 3rd coupled ♠ 13 LT 9 cwt (13,670 kg) ♥ 12 LT 19 cwt (13,160 kg)  • 4th coupled ♠ 13 LT 8 cwt (13,620 kg) ♥ 12 LT 16 cwt (13,010 kg)  • Trailing ♠ 12 LT 1 cwt (12,240 kg) ♥ 10 LT 18 cwt (11,070 kg)  • Tender bogie Bogie 1: 28 LT 16 cwt (29,260 kg) Bogie 2: 29 LT 8 cwt (29,870 kg)  • Tender axle 14 LT 14 cwt (14,940 kg) Adhesive weight ♠ 53 LT 1 cwt (53,900 kg) ♥ 51 LT 2 cwt (51,920 kg) Loco weight ♠ 79 LT 9 cwt (80,720 kg) ♥ 75 LT 18 cwt (77,120 kg) Tender weight 58 LT 4 cwt (59,130 kg) Total weight ♠ 137 LT 13 cwt (139,900 kg) ♥ 134 LT 2 cwt (136,300 kg) Tender type MS (2-axle bogies) MP, MP1, MR, MS, MX, MY, MY1 permitted Fuel type Coal Fuel capacity 11 LT (11.2 t) Water cap 5,000 imp gal (22,700 l) Firebox type Round-top  • Firegrate area ♠ 37 sq ft (3.4 m2) ♥ 36 sq ft (3.3 m2) Boiler: ​  • Model Watson Standard no. 1A  • Pitch 8 ft (2,438 mm)  • Diameter 5 ft (1,524 mm)  • Tube plates 20 ft 2 in (6,147 mm)  • Small tubes ♠ 120: 2 1⁄4 in (57 mm) ♥ 76: 2 1⁄2 in (64 mm)  • Large tubes ♠ 21: 5 1⁄2 in (140 mm) ♥ 24: 5 1⁄2 in (140 mm) Boiler pressure 200 psi (1,379 kPa) Safety valve Pop Heating surface ♠ 2,176 sq ft (202.2 m2) ♥ 1,839 sq ft (170.8 m2)  • Tubes ♠ 2,036 sq ft (189.2 m2) ♥ 1,700 sq ft (160 m2)  • Arch tubes ♠ 13 sq ft (1.2 m2) ♥ 16 sq ft (1.5 m2)  • Firebox ♠ 127 sq ft (11.8 m2) ♥ 123 sq ft (11.4 m2) Superheater: ​  • Heating area ♠ 506 sq ft (47.009 m2) ♥ 404 sq ft (37.533 m2) Cylinders Two Cylinder size 21 in (533 mm) bore 26 in (660 mm) stroke Valve gear Walschaerts Valve type Piston Couplers AAR knuckle

Performance figures Tractive effort ♠♥ 31,850 lbf (141.7 kN) @ 75%

Career Operators South African Railways Class Class 19, 19R Number in class 4 Numbers 1366–1369 Delivered 1928 First run 1928 Withdrawn 1977

The South African Railways Class 19 4-8-2 of 1928 was a steam locomotive.

In 1928, the South African Railways placed four Class 19 steam locomotives with a 4-8-2 Mountain type wheel arrangement in service. They were the forerunners of a family of light-rail branchline engines which would remain in service until the very end of the steam era. One of them was later reboilered with a Watson Standard boiler and reclassified to Class 19R.

Until 1928, the bulk of light 60 pounds per yard (30 kilograms per metre) branchline traffic on the South African Railways (SAR) was hauled by Classes 6, 7 and 8 locomotives. Due to the increase in traffic during the late 1920s, the need arose for a new and heavier type of branchline locomotive.

At the request and under the direction of Colonel F.R. Collins DSO, Chief Mechanical Engineer (CME) of the SAR from 1922 to 1929, the basic design of the new Class 19 4-8-2 steam locomotive was done by Research and Test Engineer M.M. Loubser, himself later to be appointed as CME from 1939 to 1949. In 1928, four locomotives were built in Germany by Berliner Maschinenbau AG (BMAG), the former L. Schwartzkopff. They were delivered and placed in service during that same year.

The locomotives, numbered in the range from 1366 to 1369, were in essence a lighter branchline development of the earlier Classes 15CB and 15CA heavy 4-8-2 mainline locomotives and proved to be extremely successful. They were approximately 50% more powerful than the Class 8 family and also had better speed with their larger diameter coupled wheels. They were superheated, built on bar frames and their piston valves were actuated by Walschaerts valve gear.

A feature which was to be followed for all subsequent SAR locomotives, was their relatively large firegrate area of 37 square feet (3.4 square metres). The round-topped firebox had flexible stays fitted in the breaking zones. Three support brackets tied the boiler barrel to the main bar frames. As far as practicable, mountings were fixed to a steam stand on the firebox top and fitted with extensions to the spindles to carry the handles inside the cab, within easy reach of the enginemen.