GWR 6959 Class

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Great Western Railway 6959 Class
Burton Agnes Hall at Didcot.jpg
6998 Burton Agnes Hall preserved at Didcot Railway Centre
Specifications
Power type Steam
Builder GWR/BR Swindon Works
Build date 1944–1950
Total produced 71
Configuration 4-6-0
UIC classification 2′C h2
Gauge 4 ft 8 12 in (1,435 mm)
Leading wheel
diameter
3 ft 0 in (0.914 m)
Driver diameter 6 ft 0 in (1.829 m)
Minimum curve 8 chains (530 ft; 160 m) normal,
7 chains (460 ft; 140 m) slow
Length 63 ft 0 14 in (19.21 m) over buffers
Width 8 ft 11 12 in (2.73 m)
Height 13 ft 2 in (4.01 m)
Axle load 19 tons 5 cwt (43,100 lb or 19.5 t)
Weight on drivers 57 tons 10 cwt (128,800 lb or 58.4 t)
Locomotive weight 75 tons 16 cwt (169,800 lb or 77.0 t) full
Tender weight 47 tons 6 cwt (106,000 lb or 48.1 t) full
Fuel type Coal
Fuel capacity 6 tons 0 cwt (13,400 lb or 6.1 t)
Water capacity 4,000 imp gal (18,000 l; 4,800 US gal)
Boiler pressure 225 psi (1.55 MPa)
Firegrate area 27.07 sq ft (2.515 m2)
Heating surface:
– Tubes and flues
1,582.60 sq ft (147.028 m2)
– Firebox 154.90 sq ft (14.391 m2)
Superheater area 295 sq ft (27.4 m2)
Cylinders Two, outside
Cylinder size 18.5 in × 30 in (470 mm × 762 mm)
Valve gear Stephenson, inside
Valve type Piston valves
Tractive effort 27,275 lbf (121.33 kN)
Career
Operator(s) Great Western Railway
British Railways
Power class GWR: D,
BR: 5MT
Number(s) 6959–6999, 7900-7929
Axle load class GWR: Red
Withdrawn 1963–1965

The Great Western Railway (GWR) 6959 Class or Modified Hall Class is a class of 4-6-0 steam locomotive. They were a development by Frederick Hawksworth of Charles Collett's earlier Hall Class.

The Modified Halls marked the most radical change to Swindon Works' practice since Churchward's time as chief mechanical engineer. Hawksworth's use of plate frames throughout the design was a break with Churchward's practice for 2 Cylinder locomotives. The cylinders were cast separately from the smokebox saddle and bolted to the frames on each side. A stiffening brace was inserted between the frames and extended to form the smokebox saddle. The exhaust pipes leading from the cylinders to the blastpipe were incorporated into this assembly.

Additionally Churchward's bar framed bogie which had been adapted for the original Hall in 1924 was replaced by a plate frame structure with individual springing. There were changes too above the running board. Hawksworth decided that the declining quality of coal reaching Great Western depots necessitated a higher degree of superheating. A larger three-row superheater and header regulator were fitted into Swindon No.1 boiler. Improvements were subsequently made to the draughting on some engines, while others were fitted with hopper ashpans.

The first of the Modified Halls was outshopped from Swindon in 1944. It carried plain black livery and was unnamed. After the nationalisation or Britain's railways in 1948 British Railways continued construction of this Great Western class until 1950.

Some modified Halls were equipped with a flat, high-sided Hawksworth tenders. Once he became Chief Mechanical Engineer, many earlier locomotives also received these tenders so a Hawksworth tender does not necessarily mean a Hawksworth locomotive.

List of locomotives[edit]

Preservation[edit]

Six Modified Halls are preserved on various heritage railways. A seventh survivor no 7927 Willington Hall is being used as a donor for the Grange and County re-creation projects.

Locos in Preservation[edit]

Out of the Six, half have seen main line operation: Nos. 6960 Raveningham Hall, 6990 Witherslack Hall & 6998 Burton Agnes Hall. 6960 & 6990 Saw main use in the 1980s especially in 1985 when the locos saw regular use during the GW150 Celebrations. 6998 Saw mainline action from 1986 until 1996 when she was withdrawn from operation awaiting an overhaul, Since then no Modified Hall's have been seen or run on the mainline.

Number Name Built Withdrawn Notes
6960 Raveningham Hall March 1944 June 1964 Preserved at West Somerset Railway, Operational.
6984 Owsden Hall February 1948 December 1965 Preserved at Swindon and Cricklade Railway, Undergoing Restoration.
6989 Wightwick Hall March 1948 June 1964 Preserved at Buckinghamshire Railay Centre, Undergoing Restoration.
6990 Witherslack Hall April 1948 December 1965 Preserved at Great Central Railway, Undergoing Overhaul.
6998 Burton Agnes Hall January 1949 December 1965 Preserved at Didcot Railway Centre, Awaiting Overhaul.
7903 Foremarke Hall March 1949 June 1964 Preserved at Gloucester & Warwickshire Railway, Undergoing Overhaul.

References[edit]

  • Whitehurst, Brian (1973). Great Western engines, names, numbers, types, classes: 1940 to preservation. Oxford: Oxford Publishing Company. pp. 63–64, 69, 103, 131. ISBN 0-902888-21-8. OCLC 815661. 

External links[edit]