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 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 dia 34 in (864 mm) Driver diameter 72 in (1,829 mm) Trailing dia 34 in (864 mm) Wheelbase Total: 63 ft 5.1875 in (19,334 mm) Engine: 7 ft 2 in (2,184 mm) bogie 12 ft 3.5 in (3,746 mm) coupled 33 ft 7 in (10,236 mm) total Tender: 6 ft 2 in (1,880 mm) bogie 20 ft 5 in (6,223 mm) total Length 71 ft 8.1875 in (21,849 mm) total Height 13 ft (3,962 mm) Axle load 20.65 long tons (21.0 t) on 2nd driver Adhesive weight 59.4 long tons (60.4 t) Loco 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 Loco & tender 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 mm) Fuel type Coal Fuel capacity 14 long tons (14.2 t) Water cap 6,000 imp gal (27,000 L) Boiler 6 ft 2.25 in (1,886 mm) inside diameter 19 ft 0.5 in (5,804 mm) inside length 9 ft 3 in (2,819 mm) pitch Boiler pressure Firegrate area 63 sq ft (5.853 m2) Heating surface 2,914 sq ft (270.719 m2)  • Tubes 136 tubes 2.5 in (64 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) Superheater:  • Heating 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Career Operators South African Railways Class Class 16E Number in class 6 Numbers 854–859 Delivered 1935 First run 1935 Withdrawn 1972

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

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.

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.

File:Class 16E 858 (4-6-2) driver.jpg

The drive shafts that turn the poppet valve camshafts are no different from those found under most rear wheel drive cars and trucks

With its diameter driving wheels the Class 16E was considered to be the most remarkable Cape gauge express passenger locomotive ever built. The locomotive boasted the largest fire grate on any Pacific outside North America. The driving wheels are the largest ever used on any less than 4 feet 8.5 inches (1,435 millimetres) standard gauge locomotive, and it has an all-up weight and tractive effort equal to or exceeding most Pacifics outside North America. It uses rotary cam poppet valve gear, driven by outside rotary propshafts, which resulted in extremely free-running characteristics. The centre set of driving wheels are flangeless and have wider treads than the other two sets to prevent them from slipping off the rails in sharp curves. The turning mechanisms for the poppet valve gear are mounted on this wheelset.

At 9 feet 3 inches (2,819 millimetres) 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, in diameter, which led to the superheater header and multiple valve regulator, situated in the smokebox.

Watson Standard boilers

File:SAR Class 16E 854 (4-6-2) & AG Watson.jpg

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

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.

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.

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.

File:HGG-16E-857-Schild.jpg

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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.

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.

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.

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.

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.

Illustration

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.

• SAR Class 16E 854 (4-6-2).jpg

  No. 854 at Paardeneiland Loco, Cape Town, c. 1935

• SAR Class 16E 854 (4-6-2) b.jpg

  No. 854 on the Union Limited near Roodepoort, c. 1936

• Class 16E on Blue Train.jpg

  No. 858 leaving Johannesburg on the Blue Train, c. 1969

• SAR Class 16E 858 (4-6-2) a.jpg

  No. 858 with smoke deflectors at Orange River station, 23 April 1981

• SAR Class 16E 857 (4-6-2) c.jpg

  No. 857 with smoke deflectors at Thaba Nchu, 4 July 1999

• SAR Class 16E 858 (4-6-2) c.jpg

  No. 858 with smoke deflectors at Beaconsfield, Kimberley, 3 July 1999