Rhodesia Railways 20th class

The vehicles of categories 20 and 20A of the former Rhodesian Railways (RR ) and the Zambia Railways ( ZR ) and the National Railways of Zimbabwe ( NRZ) are articulated type locomotives Garratt. They are among the largest and most appealing steam locomotive types that were used in the southern hemisphere.

With 61 copies built the locomotives to Class GMA / GMAM the SAR (120 ), Class 15/15A of the RR ( 74) and the class of GF SAR (65 ) were the Garratt -Type with the fourth largest number of items. 14 locomotives of Class 20 delivered Beyer- Peacock 1954, 1957 followed by 6 more class 20 and 40 of the Class 20A.

Technology

The locomotives have called the wheel arrangement ( 2'D1 ') ( 1'D2 '), also called " Double Mountain". This wheel arrangement also have most other large Garratt series as it combines good running properties with the tensile force of eight driving axles are also at higher speeds.

The opposite of the previous Garratt types of RR significantly increased axle load allowed for a significant increase in performance, even though a portion of the allowable additional weight was used in favor of larger inventories.

As the first and only Rhodesian class machine received a stoker furnace. Other technical features were bar frame, Reversing on obstacle, pivot with independent enactment and Fire Screen water pipes.

The class 20A differs from the class of 20 only in the size of the inner impellers, which are slightly larger in class 20 as the bogies in the class 20A as large. In addition, the machines of class 20A have a slightly higher overall weight.

The almost continuous over the full width of the vehicle front water tanks are sloped side at the top, to improve the view of the engineer's. This characteristic is normally only found in about the same time created, very similar but somewhat larger class 59 of the EAR, and in AD 60 the New South Wales Government Railways class.

The first years

The use of class 20/20a was initially under an unlucky star. The locomotives were plagued by teething; There were fractures to the frame of the engine frames and damage to the firebox. Unlike the simultaneously formed and comparable in performance Class GMA / GMAM the SAR, which was already equipped with a stable cast steel frame, the class 20/20a still had a conventional bar frame. The damage to the firebox, however, were difficult to explain, because the South African locomotives were almost identical and have made no problems.

Two locomotives, coincidentally, the first (No. 700) and the last (No. 760), had to be scrapped after clashes after a short time.

Apart from these problems met the locomotives up to expectations. It was by far the most powerful locomotives of the railway and trains were 1270 t carry on a slope of 15.5 ‰.

Zambia becomes independent

1964 Northern Rhodesia became independent. After the consequent division of the country in Zambia and Southern Rhodesia only 15 of the 59 remaining locomotives remained in Southern Rhodesia; four others were later acquired after Zambia had introduced diesel traction. These 19 machines with the numbers 705, 707, 709, 710, 714, 716, 717 and 718 (Class 20) and 723, 724, 726, 727, 729, 738, 746, 747, 749, 753 and 756 ( class 20A ) were mainly used in coal transportation between Thomson Junction to Bulawayo and Victoria Falls.

At least part of the remaining in Zambia 20/20a was retired early as 1970 and replaced by diesel locomotives.

Reconstruction

Because of the rising after the oil crisis of 1978, oil prices decided the NRZ 1978, a reconstruction program for steam locomotives, because these could be operated with cheaper domestic coal. 1980 - 1983 the remaining Garratt locomotives were completely overhauled and modernized in certain respects, including through the installation of roller bearings. The task was entrusted to private companies, especially the RESSCO plants in Bulawayo.

Work on two machines of class 20/20a were completed in 1980; the reconstruction of most of the class was, however, only at the end of the program until April 1983.

The ZR again increased in this time, one or two 20/20a in operation, and it is at least taken into consideration, it is also to modernize the incorporation of roller bearings. For details on how lacking.

Because passed through remaining in Zambia locomotives larger gaps in the numbering, the reconstructed locomotives were renumbered. The machines of class 20 were numbered 730-737, the Class 20A, the numbers 740 to 750 Three locomotives, No. 746, 747 and 749, thereby keeping their old number.

In addition, the reconstructed locomotives of classes 15/15A and 20/20a name, the Class 20 was named Matabele regiments and the class 20A received names of rivers. The only exception is the locomotive No. 747, which was given the name "Jumbo".

Operation after the reconstruction

The reconstructed locomotives of the class 20/20a were like all Garratts railway node Bulawayo stationed and deployed on routes departing from there.

Because of the difficult economic situation in Zimbabwe, the reconstructed steam locomotives remained in service longer than originally planned. It was not until the turn of the millennium, the end of steam operation was decided, and the locomotives were only used as long as it allowed the term of the boiler certificates and as long as no major damage occurred. The machines of the class 20/20a, however, were taken mainly in 1992 from the service, some came but then sporadically used when there was just Lokomotiv acute shortage. The parked locomotives were then used as spare parts, but have not scrapped.

Contrary to planning about ten locomotives of the smaller classes 14A, 15A and 16A 2006/2007 were worked up again, so that a further use, at least in shunting and in suburban and special trains. For the class 20/20a, this is not provided because a use of steam locomotives heavy freight trains is no longer planned.

Whereabouts

Both Zambia and Zimbabwe, the locomotives have been shut down after the retirement and not scrapped. The 20/20a of NRZ are the depot in Bulawayo. Some machines are preserved in museums or as Denkmalloks.

No 708 is at the Railway Museum Livingstone, 741 at the station of Ndola and # 758 at the station in Kitwe. The locomotive No. 730 (formerly No. 705) belongs to the Railway Museum of Bulawayo and is currently the only locomotive of the class that is still serviceable and it only needed minor repairs.

Summary Table

The following table contains all the locomotives that have remained in Southern Rhodesia and Zimbabwe as well as the locomotives in Zambia, present information about their whereabouts.