NZR T class

The NZR T class was a class of steam locomotive used in New Zealand; of the "Consolidation" type, popular in North America, especially with the narrow gauge Denver and Rio Grande Western Railroad.[1]

NZR T class
Goods train with T class locomotive leaving Lyttelton, ca. 1904
Type and origin Power type Steam Builder Baldwin Locomotive Works, United States Serial number 4660–4661, 4664-4667 Build date 1879 Total produced 6
Specifications Configuration: ​  • Whyte 2-8-0  • UIC 1′D Gauge 3 ft 6 in (1,067 mm) Driver dia. 36 in (914 mm) Length 44 ft 10 in (13.67 m) Adhesive weight 23.0 long tons (23.4 t; 25.8 short tons) 24.7 long tons (25.1 t; 27.7 short tons) (reboilered) Loco weight 26.2 long tons (26.6 t; 29.3 short tons) Tender weight 16.0 long tons (16.3 t; 17.9 short tons) Fuel type Coal Fuel capacity 2.1 long tons (2.1 t; 2.4 short tons) Water cap 1,300 imp gal (5,900 l; 1,600 US gal) Firebox:  • Firegrate area 15.7 sq ft (1.46 m^2) Boiler pressure 130 psi (896 kPa) 160 psi (1,103 kPa) (reboilered) Heating surface 812 sq ft (75.4 m^2) 920 sq ft (85 m^2) (reboilered) Superheater None Cylinders Two, outside Cylinder size 15 in × 18 in (381 mm × 457 mm)
Performance figures Maximum speed 18 mph (29 km/h) Tractive effort 11,700 lbf (52.04 kN) 14,300 lbf (63.61 kN) (reboilered)
Career Operators New Zealand Railways Numbers 101–106 Locale All of New Zealand First run 1880 Disposition Withdrawn, none preserved

History

By the late 1870s there was a distinct need for a powerful type of locomotive to operate the steep section of the Main South Line between Dunedin and Oamaru. As the success of the K class demonstrated the suitability of American locomotives to New Zealand's railways, an order was placed with the Baldwin Locomotive Works in 1879 for six 2-8-0 tender locomotives. Based on a design already used for the Denver and Rio Grande, it was much less decorative than the K class, but this did not detract from its performance capabilities. The largest and most powerful locomotives in the country upon their introduction, the backhead of the boiler protruded a very long way into the cab leaving very little room for the driver or fireman.

The Baldwin and Rogers locomotives reflected the styling adopted in the 1870s by American builders with elements from the Renaissance Revival and Neo-Baroque architectural styles, and with Islamic e.g. Moorish (from Alhambra) influences. Bold colours and painted decorations were used. Many Baldwin locomotives were in Olive Green ground colour, although the Baldwin N and O classes of the 1880s had Tuscan Red ground colour. [2]

In service

Because of its small diameter driving wheels, the T class was typically limited to a speed of 29 km/h (18 mph).[1] Accordingly, it was usually assigned to freight trains. In their heyday, the T class generally hauled services on the Otago Central Railway and the Main South Line between Dunedin and Oamaru. Around the beginning of the 20th century, the class received new boilers of a Belpaire design, fitted with Westinghouse air brakes and two were moved north to Auckland to assist on the newly opened North Island Main Trunk Railway. Most were also fitted with steel cabs in place of the original wooden ones, although the design fitted varied from one locomotive to another.

As time progressed, more powerful, newer locomotives progressively displaced the T class, with the four South Island-based members of the class (103-106) known to have been relegated to the quiet, lowly trafficked Tokarahi Branch. A number of the class were modified for use as yard shunters. This involved the fitting of a tender cab and moving the tender body back on the frame to provide more room for the fireman.

Withdrawal and disposal

The first T class locomotive was withdrawn in 1922, with the last example withdrawn in 1924. Some managed to survive long enough to be dumped or have components dumped when the NZR started dumping locomotives for embankment protection in 1926.[1]

Preservation

No T class locomotives have been preserved.

References

1. Palmer & Stewart 1965, p. 48.
2. New Zealand's Early American Locomotives: The Design, Art and Architecture of the K, T and O Class Locomotives Part 2 by David Fletcher: "New Zealand Railfan", March 2015 pages 33-49: Volume 21 No 2

Bibliography

• Millar, Sean (2011). The NZR Steam Locomotive. Wellington: New Zealand Railway and Locomotive Society. ISBN 978-0-908573-89-9.
• Palmer, A. N.; Stewart, W. W. (1965). Cavalcade of New Zealand Locomotives. Wellington: A H. & A W. Reed. ISBN 978-0-207-94500-7.
• Stewart, W. W. (1974). When Steam was King. Wellington: A. H. & A. W. Reed Ltd. ISBN 978-0-589-00382-1.