South African Class 16E 4-6-2

South African Class 16E 4-6-2

No. 858 at Vetrivier, 5 November 1979
Type and origin
Power type Steam
Designer South African Railways
Builder Henschel and Son
Serial number 22583-22588 [1][2]
Model Class 16E
Build date 1935
Total produced 6
Specifications
Configuration 4-6-2 "Pacific"
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading wheel
diameter		 34 in (864 mm)
Driver diameter 72 in (1,830 mm)
Trailing wheel
diameter		 34 in (864 mm)
Wheelbase Total: 63 ft 5.1875 in (19.334 m)
Engine:
7 ft 2 in (2.184 m) bogie
12 ft 3.5 in (3.747 m) coupled
33 ft 7 in (10.236 m) total
Tender:
6 ft 2 in (1.880 m) bogie
20 ft 5 in (6.223 m) total
Length 71 ft 8.1875 in (21.849 m) total
Height 13 ft (3.962 m)
Axle load 20.65 long tons (21.0 t) on 2nd driver
Weight on drivers 59.4 long tons (60.4 t)
Locomotive weight 97.75 long tons (99.3 t)
Tender weight 66,416 lb (30.1 t) empty
69.4 long tons (70.5 t) w/o
Locomotive and tender
combined weight		 192,500 lb (87.3 t) empty
167.15 long tons (169.8 t) w/o
Tender type JT - JT, JV permitted
* 2 axle bogies
* 34 in (864 mm) wheels
* Length 30 ft 9.0625 in (9.374 m)
Fuel type Coal
Fuel capacity 14 long tons (14.2 t)
Water capacity 6,000 imp gal (27,000 l)
Boiler 6 ft 2.25 in (1.886 m) inside diameter
19 ft 0.5 in (5.804 m) inside length
9 ft 3 in (2.819 m) pitch
Boiler pressure 210 psi (1,450 kPa)
Firegrate area 63 sq ft (5.853 m2)
Heating surface:
– Tubes		 136 tubes 2.5 in (63.5 mm) diameter
36 tubes 5.5 in (140 mm) diameter
2,682 sq ft (249.166 m2)
– Flues 26 sq ft (2.415 m2)
– Firebox 206 sq ft (19.138 m2)
– Total 2,914 sq ft (270.719 m2)
Superheater area 592 sq ft (54.999 m2)
Cylinders Two
Cylinder size 24 in (610 mm) bore
28 in (711 mm) stroke
Valve gear RC Poppet
Performance figures
Tractive effort 35,280 lbf (157 kN) at 75% pressure
Career
Operator(s) South African Railways [3]
Class Class 16E
Number in class 6
Number(s) 854–859
Delivered 1935
First run 1935
Withdrawn 1972 [4]

The South African Class 16E 4-6-2 of 1935 is a South African steam locomotive from the South African Railways era.

In 1935 the South African Railways placed six Class 16E steam locomotives with a 4-6-2 Pacific type wheel arrangement in passenger train service.[3]

Manufacturer

The Class 16E 4-6-2 Pacific type locomotive was designed by A.G. Watson, the Chief Mechanical Engineer (CME) of the South African Railways (SAR) from 1929 to 1936, and built by Henschel and Son in Kassel, Germany. Six locomotives were delivered in 1935, numbered in the range from 854 to 859.[2][5]

With its 72 inches (1,830 millimetres) diameter driving wheels the Class 16E was considered to be the most remarkable Cape gauge express passenger locomotive ever built. The driving wheels were the largest ever used on any less than 4 feet 8.5 inches (1,440 millimetres) standard gauge locomotive, and it had an all-up weight and tractive effort equal to or exceeding most Pacifics outside North America. It used rotary cam poppet valve gear, driven by outside rotary shafts, which resulted in extremely free-running characteristics. It also boasted the largest fire grate on any Pacific outside North America.[1][4]

CME A.G. Watson with his crowning achievement, the Class 16E, c. 1935

At 9 feet 3 inches (2.819 metres) above rail level, their boiler centre-line was the highest-pitched on the SAR. Because of this and the limitations of the loading gauge, it was impossible to install a normal steam dome and its place was taken by an inspection man-hole. Steam was collected through numerous small feeder pipes fixed into two collector pipes, which were arranged as high as possible above the water surface. The collector pipes then joined together to form a main steam pipe, 7 inches (177.800 millimetres) in diameter, which led to the superheater header and multiple valve regulator, situated in the smokebox.[1]

Watson Standard boilers

The Class 16E was delivered with a Watson Standard no. 3A boiler, one of the range of standard boiler types designed by Watson as part of his standardisation policy. It was also equipped with the altered cab with the slanted front design that, like the Watson Standard boiler, was to become standard on later SAR steam locomotive classes.[3]

Many serving locomotives were reboilered with these Watson Standard boilers and Watson cabs, and new locomotives that were acquired in the Watson era and later were built with such boilers. An obvious visual identifying feature of a Watson Standard boilered locomotive is usually a rectangular regulator cover just to the rear of the chimney.[3]

Service

The Class 16E Pacifics were placed in service at Kimberley and regularly worked trains like the Union Express, that was to become the Blue Train after World War II, and the Union Limited south to Beaufort West and north to Johannesburg. Although they were never stationed at Braamfontein Loco in Johannesburg, they were serviced there in the process of working between Kimberley and Johannesburg.[6]

They proved to be very successful, efficient and economical in service. When the original wooden bodied coaches of the Union Express were replaced with heavier steel bodied air conditioned coaches in 1939, however, the Class 16E was considered to be inadequate to the task and was relocated to Bloemfontein in the Orange Free State.[1][5][6]

From here they hauled regular passenger trains, including the Orange Express, working north to Johannesburg and south to De Aar as well as across to Kimberley. When air conditioned lounge cars were added to trains like the Orange Express and Trans-Karoo, they were again considered as not powerful enough for the additional load and were eventually withdrawn from service in 1972.[5][6]

Preservation

Two locomotives survive and were still relatively intact by 2010. Number 858, "Betty", was stored in the open at Beaconsfield, Kimberley, while number 857 was in storage at Bloemfontein, parked under cover at the locomotive depot.[7]

Commemoration

A 20c postage stamp depicting a Class 16E locomotive was one of a set of four commemorative postage stamps that were issued by the South African Post Office on 27 April 1983, to commemorate the steam locomotives of South Africa that were rapidly being withdrawn from service at the time. The artwork and stamp design was by the noted stamp designer and artist Hein Botha.[8]

The particular locomotive depicted was Class 16E no. 858. The outline of a traditional SAR locomotive number plate was used as a commemorative cancellation for De Aar on the date of issue.[8]

Sides illustrated

Class 16E locomotives were equipped with smoke deflectors in later years. The main picture shows Class 16E no. 858 without smoke deflectors, while the following pictures show both sides of the locomotive.

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 71–72. ISBN 978-0-7153-5427-8.
  2. ↑ 2.0 2.1 Henschel-Lieferliste (Henschel & Son works list), compiled by Dietmar Stresow
  3. ↑ 3.0 3.1 3.2 3.3 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, pp21 & 21A, as amended
  4. ↑ 4.0 4.1 Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. p. 96. ISBN 0715386387.
  5. ↑ 5.0 5.1 5.2 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 10–11, 67–68. ISBN 0869772112.
  6. ↑ 6.0 6.1 6.2 Information supplied by Les Pivnic, retired Assistant Curator, South African Railway Museum
  7. ↑ Middleton, John N. (2002). Railways of Southern Africa Locomotive Guide - 2002 (as amended by Combined Amendment List 4, January 2009) (2nd, Dec 2002 ed.). Herts, England: Beyer-Garratt Publications. p. 17.
  8. ↑ 8.0 8.1 Philatelic Bulletin 176, issued by Philatelic Services and INTERSAPA, 1983