| THE INDUSTRIAL RAILWAY RECORD |
© DECEMBER 1963 |
|
HUNSLET 2-6-2 TANKS |
by GEOFFREY HORSMAN |
(Although strictly speaking these locomotives are outside our field, it is thought that details will be of interest in view of their association with the engine RUSSELL described in RECORD No.2 – Hon. Ed.)
The first Hunslet locomotives for the 2’ 6" gauge Sierra Leone Government Railways were two 7½" x 12" 0−6−0 side tanks built in 1896 (Hunslet 650 and 651: SLGR 1 and 2) but these appear to have had little in common with the 2−6−2 side tank design introduced in 1898. Five 12" x 16" 2−8−2 side tanks (Hunslet 883-887: SLGR 101-105) were delivered in 1906 but these again showed no similarity to the 2−6−2 design, having inside frames and an extremely shallow firebox – so shallow in fact that the water-legs were practically non-existent. It was necessary to build a firebrick wall across the front of the grate to stop the fire going up the tubes!
Between 1898 and 1954 Hunslet built thirty-two 2−6−2 tanks to a design which altered basically very little. The table below gives the Hunslet works number, date of despatch and the SLGR (or SLR) number.
| 673 | 22. 6.1898 | SLGR 21 | 826 | 30. 7.1903 | SLGR 32 | 1202 | 28.11.1919 | SLR 43 |
| 674 | 22. 6.1898 | SLGR 22 | 834 | 11.12.1903 | SLGR 33 | 1203 | 18.12.1919 | SLR 44 |
| 675 | 22. 6.1898 | SLGR 23 | 835 | 12.12.1903 | SLGR 34 | 1204 | 8. 1.1920 | SLR 45 |
| 709 | 19. 1.1900 | SLGR 24 | 836 | 28. 1.1904 | SLGR 35 | 1409 | 17.11.1920 | SLR 46 |
| 710 | 26. 1.1900 | SLGR 25 | 837 | 9. 2.1904 | SLGR 36 | 1410 | 18.11.1920 | SLR 47 |
| 744 | 18. 4.1901 | SLGR 26 | 1011 | 18.10.1909 | SLGR 37 | 3398 | 24. 6.1947 | SLR 81 |
| 745 | 27. 4.1901 | SLGR 27 | 1012 | 21.10.1909 | SLGR 38 | 3399 | 24. 6.1947 | SLR 82 |
| 800 | 17. 1.1903 | SLGR 28 | 1013 | 21.10.1909 | SLGR 39 | 3400 | 11. 7.1947 | SLR 83 |
| 801 | 6. 2.1903 | SLGR 29 | 1014 | 25.10.1909 | SLGR 40 | 3814 | 8.10.1954 | SLR 84 |
| 802 | 13. 2.1903 | SLGR 30 | 1081 | 21. 9.1911 | SLGR 41 | 3815 | 8.10.1954 | SLR 85 |
| 825 | 17. 7.1903 | SLGR 31 | 1145 | 31.12.1913 | SLGR 42 |
Some, at least, of these engines were named, as on 5th December 1906 the Crown Agents ordered from Hunslet pairs of nameplates for Sierra Leone locomotives 1 to 24. Of these 21 to 24 were named respectively BOAGIBU, LAGO, KENNAMA and NIAWA.
I have divided the engines into six batches and indicated the main features which underwent change over the years.
| 21-27 : | raised round-top firebox; Ramsbottom safety valves inside the cab with extension tubes protruding through the roof; dome in centre of barrel; compensated spring gear; eccentric driven feed pump; steam and hand brakes; oil lamps; manual sanding |
| 28-36 : | flush round-top firebox; Ramsbottom safety valves outside the cab; dome forward of centre of barrel; larger boiler fitted in which the maximum outside diameter was increased from 2’ 5¾" to 3' 23/8"; increased water and fuel capacity; otherwise as 21−27. |
| 37-41 : | no boiler feed pump; steam and hand brakes (engine) and vacuum brake (train); otherwise as 28-36. |
| 42-47 : | fixed spring gear; otherwise as 37-41. |
| 81-83 : | Ross "pop" safety valves; increased water and fuel capacity; electric lighting; Wakefield "Eureka" type C hydrostatic lubricator; otherwise as 42-47. |
| 84-85 : | roller bearing axleboxes on the pony trucks; otherwise as 81-83. |
The upper photograph of 23 shows the double roof at that time favoured in hot countries. Several detail differences will be noted on 84 (lower), including the much smaller headlamp. (Hunslet Engine Co. Ltd.)
No details of the livery of the early engines have survived, but 43-47 are recorded as "painted Gorton green and lined out in black and chrome". 81 to 85, however, were painted black which is the present standard livery for tank engines. 26 and 27 were supplied for the extension to Bo, 33 for the extension to Baoma, and 41 for the extension to Rowalla.
The leading dimensions are as under:-
|
|
21-27 |
28-47 |
81-85 |
|
| Cylinders |
: |
10" x 15" |
10" x 15" | 10" x 15" |
| Tubes | : | 78 of 15/8" dia. | 97 of 15/8" dia. | 97 of 15/8" din. |
| Working Pressure | : | 160 lbs./sq.in. | 160 lbs./sq.in. | 160 lbs./sq.in. |
| Water Capacity | : | 350 gallons | 440 gallons | 470 gallons |
| Coal Capacity | : | 12 cwts. | 13 cwts. | 1 ton * |
| Heating Surface (Tubes) | : | 277 sq.ft. | 345 sq.ft. | 345 sq.ft. |
| Heating Surface (Firebox) | : | 35 sq.ft. | 36 sq.ft. | 36 sq.ft. |
| Grate Area | : | 6¼ sq.ft. | 6¼ sq.ft. | 6¼ sq.ft. |
| Coupled Wheels (diameter) | : | 2' 4" | 2' 4" | 2' 4" |
| Bogie Wheels (diameter) | : | 1' 6" | 1' 6" | 1' 6" |
| Coupled Wheelbase | : | 5' 6" | 5' 6" | 5' 6" |
| Total Wheelbase | : | 15' 4" | 15' 4" | 15' 4" |
* 25 cwts. on 84 and 85
The following weights have been recorded:-
(empty) : 15t. 10c.(21-23), 16t. 0c.(31-32), 16t. 16c.(42), 17t. 12c.(84-85).
(loaded) : 18t. 10c.(21-23), 20t. 2c.(31-32), 20t. 13c.(42), 22t. 9c.(84-85).
