NZR W^AB class

Specifications
Configuration:;
• Whyte	4-6-4T
Gauge	3 ft 6 in (1,067 mm)
Wheel diameter	54 in (1.372 m)[1]
Wheelbase	33 ft 1 in (10.08 m)
Length	44 ft 6 in (13.56 m)[1]
Adhesive weight	41.85 long tons (42.52 t; 46.87 short tons)[1]
Loco weight	74 long tons (75 t; 83 short tons)[1]
Fuel type	Coal
Fuel capacity	3.0 long tons (3.0 t; 3.4 short tons)[1]
Water cap	1,700 imp gal (7,700 L; 2,000 US gal)[1]
Firebox:; • Firegrate area	33.0 sq ft (3.07 m2)[1]
Boiler pressure	200 psi (1,379 kPa)[1]
Heating surface	1,050 sq ft (98 m2)[1]
Superheater:;
• Heating area	183 sq ft (17.0 m2)[1]
Cylinders	Two[1]
Cylinder size	17 in × 26 in (432 mm × 660 mm)[1]

Type and origin
Power type	Steam
Builder	NZR Addington Workshops, Christchurch (1+1) ; NZR Hillside Workshops, Dunedin (12+8) ; A & G Price Limited, Thames (3+5)
Build date	1939

NZR WAB class
	WAB 794 on its first excursion after restoration, with the Capital Connection rolling stock, on 31 August 2003.
Type and origin
Power type	Steam
Builder	NZR Addington Workshops, Christchurch (1+1) ; NZR Hillside Workshops, Dunedin (12+8) ; A & G Price Limited, Thames (3+5)
Build date	1939
Specifications
Configuration:;
• Whyte	4-6-4T
Gauge	3 ft 6 in (1,067 mm)
Wheel diameter	54 in (1.372 m)[1]
Wheelbase	33 ft 1 in (10.08 m)
Length	44 ft 6 in (13.56 m)[1]
Adhesive weight	41.85 long tons (42.52 t; 46.87 short tons)[1]
Loco weight	74 long tons (75 t; 83 short tons)[1]
Fuel type	Coal
Fuel capacity	3.0 long tons (3.0 t; 3.4 short tons)[1]
Water cap	1,700 imp gal (7,700 L; 2,000 US gal)[1]
Firebox:; • Firegrate area	33.0 sq ft (3.07 m2)[1]
Boiler pressure	200 psi (1,379 kPa)[1]
Heating surface	1,050 sq ft (98 m2)[1]
Superheater:;
• Heating area	183 sq ft (17.0 m2)[1]
Cylinders	Two[1]
Cylinder size	17 in × 26 in (432 mm × 660 mm)[1]
Performance figures
Maximum speed	60 mph (97 km/h)
Power output	1,000 bhp (750 kW)[1]
Tractive effort	22,250 lbf (99.0 kN)[1]
Career
Number in class	30 (16 WAB+14 WS)
Numbers	687 - 798
Locale	All of New Zealand
First run	1918 - 1926
Retired	1967 - 1972
Scrapped	1969 - 1972
Current owner	Feilding and District Steam Rail Society (1)
Disposition	Scrapped, three preserved

The NZR W^AB class locomotives were steam locomotives designed, built and used by New Zealand Railways Department (NZR). Their wheel arrangement is described by the Whyte notation 4-6-4T. The locomotives were designed by NZR chief draughtsman S.H. Jenkinson as tank versions of the A^B class 4-6-2 Pacific locomotive. Initially, the locomotives were separated into two classes, designated W^AB for mainline work and W^S for suburban work.[2]

The remaining locomotives were kept in service until the last days of steam, operating short-haul mainline freight services and fast suburban services, particularly in Auckland. W^AB 794 was sold to the Ohai Railway Board in Southland for running heavy coal trains. The locomotives were progressively withdrawn in the 1960s.[2]

Introduction

The first locomotives, W^S 686 and W^AB 687, were built from the boilers, frames and engine units initially destined for A^B 666 and A^B 667. These entered service in 1917, W^S 686 in Wellington and W^AB 687 at Taumarunui in the central North Island. Fourteen W^S class locomotives were built between 1917 and 1925: one at Addington workshops (686), five at A & G Price Ltd, Thames (799-803) and eight at Hillside workshops, Dunedin (764-771). All the W^S class were converted to W^AB in 1932-4. Sixteen W^AB class were built between 1918 and 1926: one at Addington (687), 12 at Hillside (786-795) and three at A&G Price (796-798). Between 1947 and 1957 11 W^AB class were converted to A^B class.

Preserved locomotives

Only three examples of the class remain, with two in their original form as W^ABs:

W^AB 794 was donated by the Ohai Railway Board in 1968 to the New Zealand Railway and Locomotive Society and was moved to the Ferrymead Railway, and displayed for the Rail 125 celebrations in 1988.[3] The locomotive has since been restored and is preserved at Feilding, and has been used on mainline excursions and also on the regular Wellington - Auckland Overlander service.

W^AB (former W^S) 800 is owned by the Waikato Branch of New Zealand Railway and Locomotive Society and was stored for many years at the Te Awamutu Railway Museum. Following the negotiation of a lease agreement, the engine has been moved to the Glenbrook Vintage Railway for eventual restoration to working order.

A^B (former W^AB) 795 is preserved at Kingston, for use on the "Kingston Flyer".

Notes

"Wab794 - Technical Information". Feilding and District Steam Rail Society. Retrieved 26 October 2014.
Palmer & Stewart 1965, p. 106.
Cavalcade125 1988, p. 10.

References

Barry, Colin; Brouwer, John; Dash, Colin; Dickenson, Peter; Shalders, Bruce (1988). Cavalcade 125. Ferrymead 125 Committee. Retrieved 22 March 2019.
Palmer, A. N.; Stewart, W. W. (1965). Cavalcade of New Zealand Locomotives. Wellington: A H. & A W. Reed. ISBN 978-0-207-94500-7.

External links

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[FDSRtech-1] "Wab794 - Technical Information". Feilding and District Steam Rail Society. Retrieved 26 October 2014.

[FOOTNOTEPalmerStewart1965106-2] Palmer & Stewart 1965, p. 106.

[FOOTNOTECavalcade125198810-3] Cavalcade125 1988, p. 10.

NZR WAB class