In December 1927 and January 1928 the South African Railways placed two Class 18 three-cylinder steam locomotives with a 2-10-2 Santa Fe type wheel arrangement in service on the Witbank-Germiston coal line.[1][2][3][4]
The Class 18 2-10-2 Santa Fe type steam locomotive was designed by Colonel F.R. Collins DSO, Chief Mechanical Engineer (CME) of the South African Railways (SAR) from 1922 to 1929, and built by Henschel and Son in Germany. Two locomotives were delivered in 1927 and 1928, numbered 1360 and 1361.[1][2][5]
CharacteristicsEdit
They were very powerful three-cylinder locomotives. At the time, three-cylindered locomotives were being built in appreciable numbers in Europe and America. Factors in their favour were their more even turning moment, improved balancing and better distribution of crank-pin thrust. Drawbacks were increased complexity and higher repair cost.[1][2][5][6][7]
Col F.R. Collins DSO
When delivered, the third cylinder was clearly visible, but plating was subsequently added beneath the smokebox and hid it from view. These were the most powerful non-articulated steam locomotives to see service on the SAR, with a tractive effort of 53,650 pounds-force (239 kilonewtons) at 75% boiler pressure and capable of hauling loads of 1,800 long tons (1,829 tonnes) over the ruling gradient of 1 in 100 (1%) on the Witbank-Apex section.[1][8]
Contemporary Henschel publicity appropriately referred to them as the "Henschel Giants". They were larger in most respects than Deutsche Reichsbahn's new Standard gaugeClass 44 three-cylinder 2-10-0 locomotives. Although their all-up locomotive weight was almost the same, when considering the fact that the SAR's Cape gauge Class 18 had shorter axles and frame stretchers, saving weight that could then be built into other items such as the firebox, the Class 18 was the larger locomotive.[6]
The Class 18 had a round-topped firebox with a combustion chamber and with arch tubes supporting the brick arch. It was fired by a Duplex D.4 type mechanical stoker, operated by a four-cylinder steam engine on its Type HT tender, which had a coal capacity of 14 long tons (14.2 tonnes), a water capacity of 6,000 imperial gallons (27,300 litres) and a maximum axle load of 19 long tons 8 hundredweight (19,710 kilograms).[2][6]
To allow the locomotive to negotiate curves of 320 feet (98 metres) radius despite its long coupled wheelbase, the third and fourth pairs of driving wheels were flangeless. In addition, the locomotive made use of a Krauss-Helmholtz bogie system, where the leading pair of driving wheels has a limited amount of sideplay with an articulated link to the leading bissel bogie. The bissel bogie was connected to a sleeve around the first driving axle so that any displacement of the bissel bogie in one direction would cause a similar displacement of the leading driving axle in the opposite direction, thereby steering the driving wheels through curves.[1][5]
The outside cylinders drove the third pair of driving wheels while the inside cylinder drove the second pair through a cranked axle, with the cylinder mounted in an inclined position. The three cranks were arranged at an angle of 120 degrees to each other, allowing for the inclination of the inner cylinder.[1][2][3][4]
ServiceEdit
The Class 18 was introduced in an attempt to ease problems which were being experienced with increasingly heavy coal trains on the line between Witbank and Germiston, where the Class MF Mallets were considered as being too sluggish and the hauling capacity of the non-articulated fleet was being stretched to the limit.[1][5]
In service, the locomotives disappointed. In spite of the two sets of flangeless coupled wheels and the Krauss-Helmholtz system, the Class 18 experienced excessive flange and tyre wear while the Chief Civil Engineer claimed increased rail wear. The cylinder design was outdated and along with the lightweight motion and rods, contributed to them being uneconomical high-maintenance machines. The complicated valve gear was not robust enough and frequently gave trouble owing to wear and breakage. The result was that the locomotives had to be shopped at under 40,000 miles (64,374 kilometres).[1][5][9]
Both Class 18 locomotives were withdrawn by 1951. After their locomotives were withdrawn from service, the two Type HT tenders had their mechanical stokers removed and their drawgear modified for use with Class 15CA locomotives. They were then redesignated Type KT.[1][5][10]
Knuckle couplersEdit
In 1927, the SAR began to convert the couplers of its Cape Gauge rolling stock from the Johnston link-and-pin coupling system which had been in use since the establishment of the Cape Government Railways in 1873, to AAR knuckle couplers. Judging from contemporary photographs as well as the official SAR Locomotive Diagram Book and the dimensional locomotive drawings as published by Holland, which were for the most part based on the original as-delivered and unmodified locomotives, the Class 18 locomotives were delivered new with knuckle couplers fitted, as were the Classes GCA, GF, HF and U which also entered service in 1927.[1][3][4]
Transition era knuckle coupler
Conversion of all rolling stock would take several years and both coupler types could still be seen on rolling stock into the late 1950s. During the transition period, knuckle couplers on locomotives had a horizontal gap and a vertical hole in the knuckle itself to accommodate a link and a pin respectively. This enabled them to couple to vehicles which were still equipped with the older Johnston couplers.[1][3][4]
Knuckle couplers had first been used in South Africa more than two decades earlier. The Central South African Railways (CSAR) introduced Gould knuckle couplers on the rolling stock of its Limited Express and Imperial Mail passenger trains in 1904. The Limited Express operated between Pretoria and Johannesburg while the Imperial Mail operated between Pretoria and Cape Town. These knuckle-couplers also had split knuckles to accommodate coupling to the old Johnston couplers with a link and pin, since the CSAR retained the old couplers on all their locomotives to keep them compatible with their own goods and older passenger rolling stock as well as with that from the other railways it connected with.[11]
IllustrationEdit
Class 18 with the third cylinder visible, as delivered, c. 1930
Class 18 with plating beneath the smokebox hiding the third cylinder
Wikimedia Commons has media related to South African Class 18 2-10-2.
^ abcdefghijkHolland, D. F. (1972). Steam Locomotives of the South African Railways. Vol. 2: 1910-1955 (1st ed.). Newton Abbott, England: David & Charles. pp. 51–52. ISBN978-0-7153-5427-8.
^ abcdeEspitalier, T.J.; Day, W.A.J. (1946). The Locomotive in South Africa - A Brief History of Railway Development. Chapter VII - South African Railways (Continued). South African Railways and Harbours Magazine, Jun 1946. pp. 453-455.
^ abcdSouth African Railways & Harbours/Suid Afrikaanse Spoorweë en Hawens (15 Aug 1941). Locomotive Diagram Book/Lokomotiefdiagramboek, 3'6" Gauge/Spoorwydte. SAR/SAS Mechanical Department/Werktuigkundige Dept. Drawing Office/Tekenkantoor, Pretoria. p. 25.
^Henschel-Lieferliste (Henschel & Son works list), compiled by Dietmar Stresow
^South African Railways & Harbours Photo Journal, Vol. 1, no 8, pp1-3, by Les Pivnic
^Soul of A Railway, System 7, Western Transvaal, based in Johannesburg, Part 21: Witbank Line by Les Pivnic, Eugene Armer, Peter Stow and Peter Micenko. Captions 6, 7. (Accessed on 4 May 2017)
^Soul of A Railway, System 8, Part 2: Pretoria: including local services, workshops and running sheds, Part 2. Caption 43. (Accessed on 18 March 2017)
^Soul of A Railway, System 8, Part 1: Pretoria: including local services, workshops and running sheds, Part 1. Captions 8, 13. (Accessed on 15 March 2017)
October 24, 2023
south, african, class, south, african, railways, class, 1927, steam, locomotive, builder, picture, class, 1927type, originpower, typesteamdesignersouth, african, railways, collins, builderhenschel, sonserial, number20787, 20788modelclass, 18build, date1927tota. The South African Railways Class 18 2 10 2 of 1927 was a steam locomotive South African Class 18 2 10 2Builder s picture of the Class 18 c 1927Type and originPower typeSteamDesignerSouth African Railways Col F R Collins DSO BuilderHenschel and SonSerial number20787 20788ModelClass 18Build date1927Total produced2SpecificationsConfiguration Whyte2 10 2 Santa Fe UIC1 E1 h3Driver3rd coupled axleGauge3 ft 6 in 1 067 mm Cape gaugeLeading dia 30 in 762 mm Coupled dia 57 in 1 448 mm Trailing dia 33 in 838 mm Tender wheels34 in 864 mm Minimum curve320 ft 98 m Wheelbase67 ft 7 3 4 in 20 618 mm Engine38 ft 2 1 4 in 11 640 mm Coupled21 ft 6 401 mm Tender20 ft 5 in 6 223 mm Tender bogie6 ft 2 in 1 880 mm Length Over couplers76 ft 23 165 mm Height13 ft 3 962 mm Axle load19 LT 19 300 kg Leading7 LT 9 cwt 7 570 kg 1st coupled18 LT 6 cwt 18 590 kg 2nd coupled18 LT 18 cwt 19 200 kg 3rd coupled19 LT 19 300 kg 4th coupled18 LT 4 cwt 18 490 kg 5th coupled18 LT 2 cwt 18 390 kg Trailing14 LT 12 cwt 14 830 kg Tender bogieBogie 1 33 LT 18 cwt 34 440 kg Bogie 2 38 LT 16 cwt 39 420 kg Tender axle19 LT 8 cwt 19 710 kg Adhesive weight92 LT 10 cwt 93 980 kg Loco weight114 LT 11 cwt 116 400 kg Tender weight72 LT 14 cwt 73 870 kg Total weight187 LT 5 cwt 190 300 kg Tender typeHT 2 axle bogies Mechanical stokerFuel typeCoalWater cap 6 000 imp gal 27 300 L Firebox typeRound top Firegrate area60 sq ft 5 6 m2 Boiler Pitch8 ft 6 in 2 591 mm Diameter6 ft 3 3 4 in 1 924 mm Tube plates20 ft 7 in 6 274 mm Small tubes160 2 1 4 in 57 mm Large tubes34 5 1 2 in 140 mm Boiler pressure215 psi 1 480 kPa Safety valvePopHeating surface3 231 sq ft 300 2 m2 Tubes2 945 sq ft 273 6 m2 Arch tubes21 sq ft 2 0 m2 Firebox265 sq ft 24 6 m2 Superheater Heating area850 sq ft 79 m2 CylindersThreeCylinder size21 1 4 in 540 mm bore28 in 711 mm strokeValve gearOuter Walschaerts Inner GresleyValve typePistonCouplersAAR knucklePerformance figuresTractive effort53 650 lbf 239 kN 75 CareerOperatorsSouth African RailwaysClassClass 18Number in class2Numbers1360 1361NicknamesHenschel GiantDelivered1927 1928First run1927Withdrawn1951The 3rd amp 4th coupled axles had flangeless wheelsIn December 1927 and January 1928 the South African Railways placed two Class 18 three cylinder steam locomotives with a 2 10 2 Santa Fe type wheel arrangement in service on the Witbank Germiston coal line 1 2 3 4 Contents 1 Manufacturer 2 Characteristics 3 Service 4 Knuckle couplers 5 Illustration 6 ReferencesManufacturer EditThe Class 18 2 10 2 Santa Fe type steam locomotive was designed by Colonel F R Collins DSO Chief Mechanical Engineer CME of the South African Railways SAR from 1922 to 1929 and built by Henschel and Son in Germany Two locomotives were delivered in 1927 and 1928 numbered 1360 and 1361 1 2 5 nbsp nbsp Characteristics EditThey were very powerful three cylinder locomotives At the time three cylindered locomotives were being built in appreciable numbers in Europe and America Factors in their favour were their more even turning moment improved balancing and better distribution of crank pin thrust Drawbacks were increased complexity and higher repair cost 1 2 5 6 7 nbsp Col F R Collins DSOWhen delivered the third cylinder was clearly visible but plating was subsequently added beneath the smokebox and hid it from view These were the most powerful non articulated steam locomotives to see service on the SAR with a tractive effort of 53 650 pounds force 239 kilonewtons at 75 boiler pressure and capable of hauling loads of 1 800 long tons 1 829 tonnes over the ruling gradient of 1 in 100 1 on the Witbank Apex section 1 8 Contemporary Henschel publicity appropriately referred to them as the Henschel Giants They were larger in most respects than Deutsche Reichsbahn s new Standard gauge Class 44 three cylinder 2 10 0 locomotives Although their all up locomotive weight was almost the same when considering the fact that the SAR s Cape gauge Class 18 had shorter axles and frame stretchers saving weight that could then be built into other items such as the firebox the Class 18 was the larger locomotive 6 The Class 18 had a round topped firebox with a combustion chamber and with arch tubes supporting the brick arch It was fired by a Duplex D 4 type mechanical stoker operated by a four cylinder steam engine on its Type HT tender which had a coal capacity of 14 long tons 14 2 tonnes a water capacity of 6 000 imperial gallons 27 300 litres and a maximum axle load of 19 long tons 8 hundredweight 19 710 kilograms 2 6 To allow the locomotive to negotiate curves of 320 feet 98 metres radius despite its long coupled wheelbase the third and fourth pairs of driving wheels were flangeless In addition the locomotive made use of a Krauss Helmholtz bogie system where the leading pair of driving wheels has a limited amount of sideplay with an articulated link to the leading bissel bogie The bissel bogie was connected to a sleeve around the first driving axle so that any displacement of the bissel bogie in one direction would cause a similar displacement of the leading driving axle in the opposite direction thereby steering the driving wheels through curves 1 5 The outside cylinders drove the third pair of driving wheels while the inside cylinder drove the second pair through a cranked axle with the cylinder mounted in an inclined position The three cranks were arranged at an angle of 120 degrees to each other allowing for the inclination of the inner cylinder 1 2 3 4 Service EditThe Class 18 was introduced in an attempt to ease problems which were being experienced with increasingly heavy coal trains on the line between Witbank and Germiston where the Class MF Mallets were considered as being too sluggish and the hauling capacity of the non articulated fleet was being stretched to the limit 1 5 In service the locomotives disappointed In spite of the two sets of flangeless coupled wheels and the Krauss Helmholtz system the Class 18 experienced excessive flange and tyre wear while the Chief Civil Engineer claimed increased rail wear The cylinder design was outdated and along with the lightweight motion and rods contributed to them being uneconomical high maintenance machines The complicated valve gear was not robust enough and frequently gave trouble owing to wear and breakage The result was that the locomotives had to be shopped at under 40 000 miles 64 374 kilometres 1 5 9 Both Class 18 locomotives were withdrawn by 1951 After their locomotives were withdrawn from service the two Type HT tenders had their mechanical stokers removed and their drawgear modified for use with Class 15CA locomotives They were then redesignated Type KT 1 5 10 Knuckle couplers EditIn 1927 the SAR began to convert the couplers of its Cape Gauge rolling stock from the Johnston link and pin coupling system which had been in use since the establishment of the Cape Government Railways in 1873 to AAR knuckle couplers Judging from contemporary photographs as well as the official SAR Locomotive Diagram Book and the dimensional locomotive drawings as published by Holland which were for the most part based on the original as delivered and unmodified loco motives the Class 18 locomotives were delivered new with knuckle couplers fitted as were the Classes GCA GF HF and U which also entered service in 1927 1 3 4 nbsp Transition era knuckle couplerConversion of all rolling stock would take several years and both coupler types could still be seen on rolling stock into the late 1950s During the transition period knuckle couplers on locomotives had a horizontal gap and a vertical hole in the knuckle itself to accommodate a link and a pin respectively This enabled them to couple to vehicles which were still equipped with the older Johnston couplers 1 3 4 Knuckle couplers had first been used in South Africa more than two decades earlier The Central South African Railways CSAR introduced Gould knuckle couplers on the rolling stock of its Limited Express and Imperial Mail passenger trains in 1904 The Limited Express operated between Pretoria and Johannesburg while the Imperial Mail operated between Pretoria and Cape Town These knuckle couplers also had split knuckles to accommodate coupling to the old Johnston couplers with a link and pin since the CSAR retained the old couplers on all their locomotives to keep them compatible with their own goods and older passenger rolling stock as well as with that from the other railways it connected with 11 Illustration Edit nbsp Class 18 with the third cylinder visible as delivered c 1930 nbsp Class 18 with plating beneath the smokebox hiding the third cylinder nbsp Cutaway diagram of a Class 18 2 10 2 locomotive nbsp Ex Type HT tender modified and redesignated Type KT c 1970References Edit nbsp Wikimedia Commons has media related to South African Class 18 2 10 2 a b c d e f g h i j k Holland D F 1972 Steam Locomotives of the South African Railways Vol 2 1910 1955 1st ed Newton Abbott England David amp Charles pp 51 52 ISBN 978 0 7153 5427 8 a b c d e Espitalier T J Day W A J 1946 The Locomotive in South Africa A Brief History of Railway Development Chapter VII South African Railways Continued South African Railways and Harbours Magazine Jun 1946 pp 453 455 a b c d South African Railways amp Harbours Suid Afrikaanse Spoorwee en Hawens 15 Aug 1941 Locomotive Diagram Book Lokomotiefdiagramboek 3 6 Gauge Spoorwydte SAR SAS Mechanical Department Werktuigkundige Dept Drawing Office Tekenkantoor Pretoria p 25 a b c d South African Railways amp Harbours Suid Afrikaanse Spoorwee en Hawens 15 Aug 1941 Locomotive Diagram Book Lokomotiefdiagramboek 2 0 amp 3 6 Gauge Spoorwydte Steam Locomotives Stoomlokomotiewe SAR SAS Mechanical Department Werktuigkundige Dept Drawing Office Tekenkantoor Pretoria pp 6a 7a 25 a b c d e f Paxton Leith Bourne David 1985 Locomotives of the South African Railways 1st ed Cape Town Struik pp 10 11 69 ISBN 0869772112 a b c Durrant AE 1989 Twilight of South African Steam 1st ed Newton Abbott David amp Charles pp 27 30 ISBN 0715386387 Henschel Lieferliste Henschel amp Son works list compiled by Dietmar Stresow South African Railways amp Harbours Photo Journal Vol 1 no 8 pp1 3 by Les Pivnic Soul of A Railway System 7 Western Transvaal based in Johannesburg Part 21 Witbank Line by Les Pivnic Eugene Armer Peter Stow and Peter Micenko Captions 6 7 Accessed on 4 May 2017 Soul of A Railway System 8 Part 2 Pretoria including local services workshops and running sheds Part 2 Caption 43 Accessed on 18 March 2017 Soul of A Railway System 8 Part 1 Pretoria including local services workshops and running sheds Part 1 Captions 8 13 Accessed on 15 March 2017 Retrieved from https en wikipedia org w index php title South African Class 18 2 10 2 amp oldid 1150494823, wikipedia, wiki, book, books, library,
