South African Class 19C 4-8-2

South African Class 19C 4-8-2

No. 2439 on the Humefield-Klipplaat line on 1 October 1989
Type and origin
Power type Steam
Designer South African Railways
Builder North British Locomotive Company
Serial number 24168-24217 [1][2]
Model Class 19C
Build date 1935
Total produced 50
Specifications
Configuration 4-8-2 "Mountain"
Gauge 3 ft 6 in (1,067 mm) Cape gauge
Leading wheel
diameter		 28.5 in (724 mm)
Driver diameter 54 in (1,370 mm)
Trailing wheel
diameter		 34 in (864 mm)
Wheelbase Total: 58 ft 8.75 in (17.901 m)
Engine:
6 ft 4 in (1.930 m) bogie
14 ft 5 in (4.394 m) coupled
32 ft 3 in (9.830 m) total
Tender:
4 ft 7 in (1.397 m) bogie
16 ft 9 in (5.105 m) total
Length 67 ft 3.625 in (20.514 m) total
Height 12 ft 10.875 in (3.934 m)
Frame Bar frame
Axle load 13.4 long tons (13.6 t) on 2nd & 3rd drivers, steel firebox
13.65 long tons (13.9 t) on 2nd & 3rd drivers, copper firebox
Weight on drivers 53.1 long tons (54.0 t) steel firebox
54.1 long tons (55.0 t) copper firebox
Locomotive weight 78.35 long tons (79.6 t) steel firebox
79.65 long tons (80.9 t) copper firebox
Tender weight 48,864 lb (22.2 t) empty
52.35 long tons (53.2 t) w/o
Locomotive and tender
combined weight		 160,720 lb (72.9 t) empty
130.7 long tons (132.8 t) w/o, steel firebox
131 long tons (133.1 t) w/o, copper firebox
Tender type MR - MP, MP1, MR, MX, MY, MY1 permitted
* 2 axle bogies
* 34 in (864 mm) wheels
* Length 25 ft 9.75 in (7.868 m)
Fuel type Coal
Fuel capacity 10 long tons (10.2 t)
Water capacity 4,600 imp gal (21,000 l)
Boiler 5 ft (1.524 m) inside diameter
20 ft 2 in (6.147 m) inside length
8 ft (2.438 m) pitch
Boiler pressure 200 psi (1,380 kPa)
Firegrate area 36 sq ft (3.345 m2)
Heating surface:
– Tubes		 76 tubes 2.5 in (63.5 mm) diameter
24 tubes 5.5 in (140 mm) diameter
1,700 sq ft (157.935 m2)
– Firebox 123 sq ft (11.427 m2)
– Total 1,823 sq ft (169.362 m2)
Superheater area 404 sq ft (37.533 m2)
Cylinders Two
Cylinder size 21 in (533 mm) bore
26 in (660 mm) stroke
Valve gear RC Poppet
Performance figures
Tractive effort 31,850 lbf (142 kN) at 75% pressure
Career
Operator(s) South African Railways [3]
Class Class 19C
Number in class 50
Number(s) 2435–2484
Delivered 1935
First run 1935
Retired 1978

The South African Class 19C 4-8-2 of 1935 is a South African steam locomotive from the South African Railways era.

In 1935 the South African Railways placed fifty Class 19C steam locomotives with a 4-8-2 Mountain type wheel arrangement in service.[1][4]

Manufacturer

When the need for more branchline locomotives became apparent in 1934, tenders were invited by the South African Railways (SAR) for another fifty Class 19B locomotives with Walschaerts valve gear. When the tenders were received it was found that the North British Locomotive Company (NBL) of Glasgow, Scotland, had also tendered for a locomotive with Rotary Cam Poppet valve gear.[1][4]

Even though this would increase the cost per locomotive by £200, Chief Mechanical Engineer (CME) A.G. Watson decided to adopt it in view of the good reports he had received concerning Poppet valve gear. This variation on the design led to these locomotives being classified as Class 19C when they were delivered in 1935.[1][4]

Class 19C after a record speed test run

All fifty Class 19C loco­motives were erected at the Salt River shops, numbered in the range from 2435 to 2484, and many remained stationed at Cape Town while being subjected to exhaustive testing.[1]

The photograph alongside shows a Class 19C loco­motive after a record speed test run, during which the engine achieved a speed of 67 miles per hour (108 kilometres per hour). CME A.G. Watson is standing sixth from left in the group in front of the locomotive, with hat in hand.

Characteristics

Watson Standard boilers

The Class 19C was delivered with a Watson Standard no. 1A boiler, one of the range of standard boiler types designed by Watson as part of his standardisation policy. It had a larger superheater than the Class 19B and was equipped with the altered cab with the sloping front design that, like the Watson Standard boiler, was to become standard on later SAR steam locomotive classes.

In a break with prior custom, to facilitate easier removal of the boiler for repairs, the ash pan and running boards were affixed to the locomotive frame instead of to the boiler.[5]

Fireboxes

Some of the locomotives were built with steel fireboxes for use in those areas where good or treated water was readily available, while others were still equipped with copper or composite fireboxes for use in areas with poor water quality.[3]

Copper or composite fireboxes are considerably more expensive to manufacture and repair than steel ones. It was only by the late 1960s, when severe corrosion was no longer a big problem as a result of the availability of water treatment throughout the country, that copper and composite fireboxes were no longer considered necessary.[6]

Balancing

The balancing of these locomotives represented another advance on former practices. Until then, locomotives had been balanced to an extent of 50% to 70% of their reciprocating parts, and fully as regards their revolving parts.[1]

On the Class 19C the proportion of reciprocating parts balanced was reduced to 20%, which resulted in a big decrease of vertical hammer blow to not more than 0.9 long tons (0.91 tonnes) on any wheel at 50 miles per hour (80 kilometres per hour). Similar balancing metods on subsequent new locomotives enabled the SAR to adopt axle loads exceeding those permitted on many other railways of the world for comparable weight of rail.[1]

Service

The Class 19C was designed for mainline as well as branchline service. They initially worked in the Witwatersrand area, the Eastern Cape and Western Cape. The Poppet valves made the Class 19C a very free-running locomotive, although it required special maintenance techniques.[4][5]

As a result the whole class was allocated to the Western Cape during World War II, based at the Paardeneiland shed in Cape Town. From here they worked on branchlines such as those from Cape Town to Saldanha, along the long branchline via Klawer to Bitterfontein, and across Sir Lowry's Pass to Caledon and Protem in the Overberg.[4][5][7][8]

In later years, around 1970, a few were stationed at Bloemfontein from where they worked the line to Aliwal North. They were withdrawn from service in 1978.[4]

One, number 2439, was preserved but none of them were sold into industry, firstly because of the special maintenance required for the Poppet valves, and secondly because Cape Town was a long distance away from any potential industrial operators, which would increase the cost of relocation after purchase.[5]

Service illustrated

The main picture shows Class 19C no. 2439 on the line between Humefield and Klipplaat on 1 October 1989. While it was equipped here with a Type MX Vanderbilt tender from a Class 19D locomotive, the locomotive is now being preserved at the Outeniqua Transport Museum with an original Type MR tender.

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 68–71. ISBN 978-0-7153-5427-8.
  2. ↑ North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
  3. ↑ 3.0 3.1 South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 10–11, 69–72. ISBN 0869772112.
  5. ↑ 5.0 5.1 5.2 5.3 Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. pp. 63–64. ISBN 0715386387.
  6. ↑ SAR Code of Practice No. 7 (Boilers), Part 3A.811 dated May 1968 - Procedure to be followed when copper plates of complete copper or composite fireboxes require to be renewed
  7. ↑ Warrenton, Town, SAR Class 19D no. 2688
  8. ↑ SAR Class 19C 4-8-2 (with MX tender) Locomotive