GWR 4575 Class

The Great Western Railway (GWR) 4575 Class is a class of 2-6-2T British steam locomotives.

GWR 4575 class
4598 at Swindon Works in 1954
Type and origin Power type Steam Designer Charles Collett Builder GWR Swindon Works Order number Lots 242, 249, 251, 253 Build date 1927–1929 Total produced 100
Specifications Configuration: ​  • Whyte 2-6-2T  • UIC 1′C1′ h2t Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Leading dia. 3 ft 2 in (0.965 m) Driver dia. 4 ft 7+1⁄2 in (1.410 m) Trailing dia. 3 ft 2 in (0.965 m) Minimum curve 5 chains (330 ft; 100 m) normal, 4.5 chains (300 ft; 91 m) slow Wheelbase 26 ft 10 in (8.18 m) Length 36 ft 4+1⁄2 in (11.09 m) over buffers Width 8 ft 9 in (2.667 m) Height 13 ft 0 in (3.962 m) Axle load 15 long tons 11 cwt (34,800 lb or 15.8 t) (17.4 short tons) full Adhesive weight 46 long tons 5 cwt (103,600 lb or 47 t) (51.8 short tons) full Loco weight 61 long tons 0 cwt (136,600 lb or 62 t) (68.3 short tons) full Fuel type Coal Fuel capacity 3 long tons 14 cwt (8,300 lb or 3.8 t) Water cap. 1,300 imp gal (5,900 L; 1,600 US gal) Firebox: ​  • Grate area 16.6 sq ft (1.54 m2) Boiler GWR Standard No. 5[1] Boiler pressure 200 lbf/in2 (1.38 MPa) Heating surface: ​  • Firebox 94.25 sq ft (8.756 m2)  • Tubes 992.51 sq ft (92.207 m2) Superheater: ​  • Type 4-element or 6-element  • Heating area 4-element: 52.98 sq ft (4.922 m2), 6-element: 69.84 sq ft (6.488 m2) Cylinders Two, outside Cylinder size 17 in × 24 in (432 mm × 610 mm) Valve gear Stephenson Valve type Piston valves Train brakes Vacuum
Performance figures Tractive effort 21,250 lbf (94.5 kN)
Career Operators GWR » BR Class 4575 Power class GWR: C, BR: 4MT Number in class 100 Numbers 4575–4599, 5500–5574 Nicknames Small Prairie Axle load class GWR: Yellow Withdrawn 1956–1964 Preserved 4588, 5521, 5526, 5532, 5538, 5539, 5541, 5542, 5552, 5553, 5572 Disposition 11 preserved, remainder scrapped

History

They were designed as small mixed traffic branch locomotives, mainly used on branch lines. They were a development of Churchward's 4500 Class with larger side tanks and increased water capacity.^[2] 100 were built numbered 4575–4599 and 5500–5574. 15 (Nos. 4578/81/89, 5511/24/29/34/35/45/55/59/60/68/72/74) were fitted with auto apparatus in 1953 to enable them to run push-pull trains on South Wales lines with auto trailers.^[2]

They often are referred to as Small Prairie Class tank locomotives.

Table of orders and numbers^[3]

Year	Quantity	Lot No.	Locomotive numbers	Notes
1927	30	242	4575–4599, 5500–5504
1927	20	249	5505–5524
1928	20	251	5525–5544
1928–29	30	253	5545–5574

Preservation

11 members of the class have been preserved:

Number and name	Home	Status	Image
4588	Peak Rail	Has run in preservation,[when?] but currently out of service requiring overhaul.[as of?] It was sold from the Dartmouth Steam Railway in 2015 and is now owned by Mike Thompson and based at Peak Rail.[4]
5521/L.150	Epping Ongar Railway[5]	Built in 1927, withdrawn by BR[year needed] and sent to Woodham Brothers scrapyard, having run just over 1,000,000 miles (1,600,000 km). Saved with classmates 4561 and 5542 by the West Somerset Railway Association, but was sold with 5542 to repay purchase debts and to fund restoration of 4561. Bought by Richard and William Parker in 1980, it was restored at the Flour Mill, Forest of Dean from 2004 to 2007. It was featured in the 2007 Wolsztyn Parade,[6] then travelled to Budapest, Hungary where it worked intermittently with MAV Nosztalgia, including piloting the Orient Express. It returned to Poland in 2008, operating suburban services from Wroclaw to Jelcz Laskowice. After a third appearance at the 2009 Wolsztyn Parade, it was returned to England. In May 2013, it was painted in London Transport livery and numbered L.150 to commemorate the 150th anniversary of the Metropolitan line. Returned to traffic in 2021 following overhaul.[7]
5526	South Devon Railway	On loan to the Gwili Railway.[as of?] Boiler ticket expires in 2027.
5532	Llangollen Railway	Under restoration.[8][as of?]
5538	The Flour Mill, Forest of Dean, Gloucestershire	Under restoration.[as of?] Previously displayed in Barry Island.[9][until when?]
5539	Barry Tourist Railway	Under restoration.[as of?] Previously part of the Barry Ten until 2006.[10]
5541	Dean Forest Railway	Currently operational as of 2023. Boiler ticket expires in 2024.[11]
5542	South Devon Railway	Currently under overhaul at the South Devon Railway.[as of?] This locomotive has visited several preserved railways throughout her preservation career.[12]
5552	Bodmin and Wenford Railway	Returned to service in 2023 after overhaul, having previously run from 2003 to 2013.[13]
5553	Peak Rail	Owned by Pete Waterman. Last steam engine to leave Woodham Brothers scrapyard in Barry, Vale of Glamorgan, South Wales, in January 1990. First resteamed in 2002, running until 2012, mostly at the West Somerset Railway. Moved in 2015 from Crewe Heritage Centre for overhaul, which was completed in 2021 at Peak Rail. Currently operational, boiler ticket expires 2031.
5572	Didcot Railway Centre	On static display awaiting overhaul.[14][as of?]

Two members of the class have also briefly been out on the mainline: 5521 and 5572. 5521 was shipped to Poland in 2007 to take part in the Wolsztyn Parade, as well as briefly piloting the Orient Express. 5572 made an appearance at an open day in Reading as part of the GWR 150 celebrations in 1985, arriving under its own power. When returning to Didcot again under its own power the engine also hauled the replica broad gauge locomotive "Iron Duke" alongside the preserved GWR Railcar W22W.^{[citation needed]}

Models and toys

Lima made a model^[when?] of the 4575 class, number 4589, in GWR green, also a British Railways black-liveried version, running number 5574. Bachmann Branchline have for many years^[when?] made various versions of the 4575 Class.

See also

• GWR 4400 Class
• GWR 4500 Class
• List of GWR standard classes with two outside cylinders