NZR G class (1874)

NZR G Class (1874)

Type and origin Builder Black, Hawthorn & Co (4) Build date 1873

Specifications Configuration 4-4-0T Driver dia. 36 in (0.914 m) Adhesive weight 13.2 long tons (13.4 t; 14.8 short tons) Loco weight 18.2 long tons (18.5 tonnes; 20.4 short tons) Firebox:  • Firegrate area 9 sq ft (0.84 m^2) Boiler pressure 130 lbf/in^2 (0.90 MPa) Heating surface 486 sq ft (45.2 m^2) Cylinders Two, outside Cylinder size 10.5 in × 18 in (267 mm × 457 mm)

Performance figures Tractive effort 4,893 lbf (21.77 kN)

Career Operators NZR Disposition All scrapped

The NZR G Class was a class of four saddle tank locomotives from English builders Black Hawthorn in the early 1870s. Like the similarly sized D class, they were an attempt to produce a passenger version of the already highly successful F class.

Origin and design

The G class were ordered by the Canterbury Provincial Council. They were derived from the F class, replacing the first of the three driving axles with a four-wheel bogie. It was hoped that the reduced rigid wheelbase would allow the locomotive to provide higher speed passenger services. The type suffered from lack of weight on the driving axles, a driver stating that "it took the 'G' all its time to push its front bogie along, let alone pull a load".^[1] They were followed by the L Class which were a more successful attempt to produce a faster F Class.

Service

In the early 1890s the locomotives were progressively transferred to the Picton section, where it was felt that they had been relegated to get rid of them from the busy Hurunui-Bluff section.

Withdrawal & Disposal

All of the locomotives were withdrawn between 1915 and 1919 and were sold for further service in industry.

Class register

Key:	In service	Out of service	Preserved	Overhaul/Repair	Scrapped

Number	Builder	Entered service	Withdrawn	Notes
55	Black Hawthorn	1-1-1875	24-7-1915	Sold to NZ Coal & Oil Co., Kaitangata (1915–27), Shag Point Coal Co., Shag Point (1927-1936)
56	Black Hawthorn	1-1-1875	20-7-1918	Manawatu County Council, Sanson Tramway (1918–44)
57	Black Hawthorn	3-1-1875	23-6-1917	Castlecliff Railway Co., (1917–56) Display at Opunake 1957-1970. Scrapped in 1971
58	Black Hawthorn	2-1-1875	31-3-1919	Gamman & Co., (1919–38)

References

Citations

1. Millar 2011, p. 108.

Bibliography

• Lloyd, W.G. (2002); Register of New Zealand Railways Steam Locomotives 1863-1971, Otago Railway & Locomotive Society/Triple M Publications
• Millar, Sean (2011). The NZR Steam Locomotive. New Zealand Railway & Locomotive Society. ISBN 978-0-908573-89-9.
• W.W.Stewart (1970), When Steam Was King, REED