GWR 6959 Class

Great Western Railway 6959 Class

6990 Witherslack Hall with a Collett tender
Type and origin
Power type Steam
Builder GWR/BR Swindon Works
Build date 1944–1950
Total produced 71
Specifications
Configuration 4-6-0
UIC class 2′C h2
Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge
Leading dia 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 1⁄4 in (19.21 m) over buffers
Width 8 ft 11 1⁄2 in (2.73 m)
Height 13 ft 2 in (4.01 m)
Axle load 19 long tons 5 cwt (43,100 lb or 19.6 t)
Adhesive weight 57 long tons 10 cwt (128,800 lb or 58.4 t)
Loco weight 75 long tons 16 cwt (169,800 lb or 77 t) full
Tender weight 47 long tons 6 cwt (106,000 lb or 48.1 t) full
Fuel type Coal
Fuel capacity 6 long tons 0 cwt (13,400 lb or 6.1 t)
Water cap 4,000 imp gal (18,000 l; 4,800 US gal)
Firebox:
 • Firegrate area		 27.07 sq ft (2.515 m2)
Boiler pressure 225 psi (1.55 MPa)
Heating surface:
 • Tubes and flues		 1,582.60 sq ft (147.028 m2)
 • Firebox 154.90 sq ft (14.391 m2)
Superheater:
 • Heating 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
Performance figures
Tractive effort 27,275 lbf (121.33 kN)
Career
Operators Great Western Railway
→ British Railways
Power class GWR: D,
BR: 5MT
Numbers 6959–6999, 7900-7929
Axle load class GWR: Red
Withdrawn 1963–1965
Disposition Six preserved, remainder scrapped

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 named after English and Welsh country houses.

Background

Although the GWR had been at the forefront of British locomotive development between 1900 and 1930, the 1930s saw a degree of complacency at Swindon reflected in the fact that many designs and production methods had not kept pace with developments elsewhere. This was especially true with the useful GWR 4900 Class, the design of which largely originated in the 1900s and had not fundamentally changed since the mid-1920s.[1] Charles Collett was replaced as the Chief Mechanical Engineer of the Railway by F.W. Hawksworth in 1941 who immediately created a modified version of the design, known as the 'Modified Hall Class'.

Design

The Modified Halls marked the most radical change to Swindon Works' practice since Churchward's time as chief mechanical engineer and was very far from a simple modification of the Hall design. 'Although in outward appearance it looked almost the same, nearly everything about it was new.'[2] 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 prototype 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.

Production

6998 Burton Agnes Hall a British Railways built locomotive, with a Hawksworth flat-sided tender.

The first batch of twelve Modified Halls was delivered from Swindon works between March and September 1944. They carried plain black livery were unnamed and numbered 6959-6970 (immediately following the Hall Class sequence. They were all subsequently named between 1946 and 1948.

A further batch of ten locomotives appeared during October and November 1947 and others were on order when the nationalisation or Britain's railways took place in 1948. British Railways continued construction of this class until November 1950, by which time there were seventy-one examples.[3]

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.

Assessment

The Modified Hall class 'ran freely, steamed well and were popular with both footplate and maintenance staff. After the unambitious designs of Collett's final years, they restored Swindon's reputation.'[4] Fourteen survived until the end of steam on the former GWR in 1965.

List of locomotives

Preservation

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

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 Status Current Location Notes
6960 Raveningham Hall March 1944 June 1964 Operational West Somerset Railway
6984 Owsden Hall February 1948 December 1965 Undergoing Restoration Swindon and Cricklade Railway Undergoing restoration from ex Barry scrapyard condition.
6989 Wightwick Hall March 1948 June 1964 Undergoing Restoration Buckinghamshire Railway Centre
6990 Witherslack Hall April 1948 December 1965 Operational Great Central Railway Recently returned to traffic from a major overhaul which included the pairing with an authentic Hawksworth tender which was formerly paired with 4930 Hagley Hall.
6998 Burton Agnes Hall January 1949 December 1965 Static Display Didcot Railway Centre Awaiting Overhaul. Famed for working the GWS Vintage trains which used vintage GWR carriages.
7903 Foremarke Hall March 1949 June 1964 Undergoing Overhaul Gloucestershire and Warwickshire Railway

References

  1. ↑ Herring, Peter (2004). Classic British Steam Locomotives. Wigston: Abbeydale Press. p. 158. ISBN 1 86147 138 6.
  2. ↑ Nock, Oswald Stevens (1984). British Locomotives of the Twentieth Century. 2: 1930-1960. London: Book Club Associates. p. 94.
  3. ↑ le Fleming, H.M. (November 1960) [1953]. White, D.E., ed. The Locomotives of the Great Western Railway, part eight: Modern Passenger Classes (2nd ed.). Kenilworth: RCTS. pp. H33–4.
  4. ↑ Herring 2004, p. 159

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