SAR class NG 15

SAR class NG 15
NG 15 at Huemewood Road Depot, Port Elizabeth (1981)
Numbering:	see text
Number:	21st
Year of construction (s):	1931-1957
Retirement:	1990s
Type :	1'D1 'h2
Gauge :	610 mm
Length over coupling:	16,560 mm
Service mass:	36.6 t
Service mass with tender:	68.3 t
Friction mass:	26.81 t
Wheel set mass :	6.88 t
Driving wheel diameter:	864 mm
Impeller diameter:	k. A.
Cylinder diameter:	400 mm
Piston stroke:	450 mm
Boiler overpressure:	118 N / cm²
Grate area:	1.58 m²
Superheater area :	21.5 m²
Evaporation heating surface:	95.5 m²
Train brake:	Suction air brake

The locomotives of class NG 15 of the South African Railways (SAR) are tenders - steam locomotives for 610 mm narrow gauge ( NG stands for Narrow Gauge ); They are among the largest and most powerful stiff-framed, i.e. non-articulated steam locomotives built for this gauge. Together with their comparatively large tender, they are even longer than the Garratts in class NGG 13/16 .

technology

The NG 15 delivered from 1931 are based on the NG 5 class from 1922. Like these, they have the 1'D1 '(Mikado) wheel arrangement and thus an unusually high number of axles for stiff-framed locomotives of this gauge. Cylinder dimensions, drive wheel diameter, boiler pressure and thus also the calculated pulling force were the same for both classes.

Frame of the NG 120 dismantled into its individual parts in Porthmadog, WHHR

Superheated steam boiler of NG 134 in Dinas, WHR

The locomotives have outer frames and outer cylinders. Driving rods and coupling rods are attached to crank webs outside the frame, a design that is almost inevitable for large steam locomotives with this narrow gauge. The control corresponds to the type Walschaerts / Heusinger. The locomotives are fired with coal.

The front running axle of the NG 15 is - unlike the NG 5 class - connected to the first coupling axle to form a Krauss-Helmholtz steering frame, which enabled the machines to drive better through tight curves.

The locomotives were equipped with relatively modern equipment, including shaking grates, a self-cleaning smoke chamber , a generator and electrical lighting. As is customary in South Africa to this day, they had a suction air brake . An unusual detail is the seat that can be swiveled out to the side for the engine driver, which ensures better visibility and cooling.

The four-axle tender is even larger than that of the NG 5 class and almost as long as the locomotive itself. With a weight of 31.7 tons, it is almost as heavy with full supplies. It holds 13 m³ of water and 5.5 t of coal and gives the locomotive a long range that was necessary in the arid regions of southern Africa. Its water box, which is pulled down outside the frame for reasons of focus, gives it a box-shaped appearance.

Manufacturers and supplies

NG 15 No. 17 on the Sandstone Estates

All NG 15 were built for the 600 mm track network in South West Africa (now Namibia). The first three NG 15 (No. NG 17-19) were delivered by the Henschel works in 1931 , from which class NG 5 already came. The locomotives no. NG 117-119 followed in the same year. Franco-Belge supplied the numbers NG 120-124 in 1949 and the numbers NG 132-136 in 1952. The last delivery in 1957 (No. NG 144-148) was again made by Henschel, not to SAR, but for the Tsumeb Corporation's mining railway . In total, this type of construction was procured over a period of 26 years.

Use in South Africa

NG124 in Van Stadens station, South Africa, April 1985

By 1961, the entire route network in South West Africa including the mining railway in Tsumeb had been converted to Cape Gauge. All 21 NG 15 were then relocated to Port Elizabeth in South Africa, from where they were used on the 283 km long Avontuur Railway - the longest 2-foot route in the world. After diesel locomotives had been used on this route since the end of the 1970s, the NG 15 were gradually retired by the end of the 1980s.

The NG 15 proved themselves alongside the Garratts of classes NGG 13 and 16 and were more popular with locomotive staff because of their more spacious cab and with maintenance staff because of their simpler and more easily accessible technology. Rumor has it that the robust locomotives could reach speeds of up to 80 km / h, which, however, was well above the permissible speed.

Preserved locomotives

NG 15 No. 133 of the WHR in the Dinas train station

Of the 21 locomotives, 10 made it abroad, four to Wales (three to the Welsh Highland Railway ), two to England, two to Australia, one to Texas and one to the Schinznacher Baumschulbahn in Switzerland. The latter, however, has been sold and returned to South Africa for restoration in 2008. Most of these locomotives are inoperable; however, a repair of some copies is planned or already in progress.

Locomotive No. 120 came to the Welsh Highland Heritage Railway (WHHR) and was dismantled into its individual parts for a possible restart. It was sold by the Society to one of its members in 2009. The restoration work on No. 134 of the WHR (Caernarfon) began in October 2008; the tender will be rebuilt so that it can be operated in both directions. The sister locomotive 133 is parked on the WHR premises in Dinas near Caernarfon .

Seven of the NG 15 remaining in South Africa were still in Port Elizabeth until 2010. Most of them had been parked in the open for decades and had deteriorated accordingly. With the clearing of the station area, locomotives 132, 144, 145 and 148 were scrapped for the first time in this series.

However, some locomotives were repaired or at least saved from deterioration. No. 122 is in the Outeniqua Railway Museum in George and No. 147 as a monument locomotive in Avontuur. Locomotives 17 and 19, both from the first delivery in 1931, are owned by Sandstone Estates; No. 17 is operational. Locomotive No. 119 was restored in Port Elizabeth and has been available for the Apple Express since October 2008 . Locomotive No. 124 has also been operational again there since July 2018.

Overview table

Remaining of NG 15
17th	Sandstone Estates, South Africa	132	scrapped, most recently in Port Elizabeth, South Africa
18th	Hempstead and Northern Railroad, Texas	133	Welsh Highland Railway, Wales
19th	Sandstone Estates, South Africa	134	Welsh Highland Railway, Wales
117	Port Elizabeth, South Africa	135	Exmoor Steam Railway, England
118	Bennett Brook Railway, Australia	136	Sandstone Estates, South Africa
119	Port Elizabeth, South Africa	144	scrapped, most recently in Port Elizabeth, South Africa
120	Welsh Highland Heritage Railway, Wales	145	scrapped, most recently in Port Elizabeth, South Africa
121	Rampton Trust, England	146	Brecon Mountain Railway, Wales
122	Outeniqua Railway Museum, South Africa	147	Avontuur, South Africa
123	Bennett Brook Railway, Australia	148	scrapped, most recently in Port Elizabeth, South Africa
124	Port Elizabeth, South Africa

Individual evidence

1. ↑ - ( Memento of the original from December 21, 2008 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. 
2. ↑ - ( Memento of the original from December 21, 2008 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. 
3. ↑ https://www.facebook.com/groups/1660565170865150/permalink/2102167273371602/

literature

• David Payling: Narrow gauge locos of South West Africa. Part 3 - Class NG 15 2-8-2. In: Continental Modeller. Vol. 31, May 2009, ISSN  0955-1298 , pp. 278-280, online (PDF; 2.48 MB) .

Web links

Commons : SAR class NG 15 (Franco-Belge)  - collection of images, videos and audio files

Commons : SAR class NG 15 (Henschel)  - collection of images, videos and audio files

• The NG 15 of the Welsh Highland Railway (Engl.)
• The Restoration of NG15 Class Locomotive No. 134 (engl.)
• Images of South African narrow-gauge steam locomotives (Engl.)
• The history of the NG 15 of Sandstone Estates (Engl.)