GWR 6000 Class

6000 King-class
6024 King Edward I at Didcot
Type and origin Power type Steam Designer Charles Collett Builder GWR Swindon Works Order number Lots 243, 267, 309 Build date 1927–1928 (20), 1930 (10), 1936 (1) Total produced 31
Specifications Configuration: ​  • Whyte 4-6-0 Gauge 4 ft 8+1⁄2 in (1,435 mm) Leading dia. 3 ft 0 in (0.914 m) Driver dia. 6 ft 6 in (1.981 m) Minimum curve 8 chains (530 ft; 160 m) normal, 7 chains (460 ft; 140 m) slow Length 68 ft 2 in (20.78 m) over buffers Width 8 ft 11+1⁄2 in (2.73 m) Height 13 ft 4+3⁄4 in (4.08 m) Axle load 22 long tons 10 cwt (50,400 lb or 22.9 t) full Adhesive weight 67 long tons 10 cwt (151,200 lb or 68.6 t) full Loco weight 89 long tons 0 cwt (199,400 lb or 90.4 t) full Tender weight 46 long tons 14 cwt (104,600 lb or 47.4 t) full Total weight 135 long tons 14 cwt (304,000 lb (137.9 t)) 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) Boiler GWR Number 12 Boiler pressure 250 lbf/in2 (1.72 MPa) Heating surface: ​  • Firebox 194 sq ft (18.0 m2)  • Tubes 2,008 sq ft (186.5 m2) Superheater: ​  • Heating area 313 sq ft (29.1 m2) Cylinders Four, two inside, two outside Cylinder size 16.25 in × 28 in (413 mm × 711 mm) Valve gear Inside cylinders: Walschaerts Outside cylinders: derived from inside cylinders via rocking bars
Performance figures Tractive effort 40,300 lbf (179.3 kN) original , 39,700 lbf (176.6 kN) after 1st overhaul
Career Power class GWR: Special BR: 8P Number in class 30 Official name King-class Axle load class GWR: Double Red Withdrawn 1936 (1), 1962 (30) Preserved 6000, 6023, 6024 Disposition Three preserved, remainder scrapped.

The Great Western Railway 6000 Class or King is a class of 4-6-0 steam locomotive designed for express passenger work. With the exception of one Pacific (The Great Bear), they were the largest locomotives the GWR built. They were named after kings of the United Kingdom and of England, beginning with the reigning monarch, King George V, and going back through history. Following the death of King George V, the highest-numbered engine was renamed after his successor; and following the abdication of the latter, the next-highest engine was also renamed after the new King.

Background

This class was designed under the direction of C. B. Collett, as an enlarged version of Collett's Castle Class, which in turn was an enlargement of George Jackson Churchward's Star Class. Churchward had proposed fitting the 6ft diameter boiler used on his 4700 Class 2-8-0 on to a 4-6-0 chasis in 1919 to create a more powerful express locomotive, but had been prevented from doing so due to weight restrictions on several bridges on the GWR main line. Collet's Castle class of 1923 was therefore a compromise with a 5' 6" boiler. However, bridge strengthening and a better understanding of the impact of hammer blow on structures brought about by the work of the 'Bridge Stress Committee' set up by the Department of Scientific and Industrial Research led to the relaxation of these restrictions.

The new design was partly to meet future traffic requirements, but was also a response to the Great Western Railway publicity department's desire to regain the title of having the 'most powerful express passenger steam locomotive in Britain', which had been taken from the Castle Class in 1926 by the Southern Railway Lord Nelson Class. The engines, as originally designed, delivered 39,700 lbf (177,000 N) tractive effort, with 16-inch bore by 28-inch stroke cylinders and 250 pounds per square inch (1.72 MPa) boiler. At a request from Sir Felix Pole, the Great Western's General Manager, to get the tractive effort up to above 40,000 lbf (a major goalpost), the cylinders were enlarged to 16+1⁄4-inch bore, bringing the figure up to 40,300 lbf (179,000 N). This increase was removed on all members of the class at their first major overhaul. The distinctive design of the leading bogie (with outside bearings on the fore wheel and inside bearings on the rear wheel) was to allow for these larger cylinders.

The first, No. 6000 King George V, appeared in 1927 and was sent on a tour of North America, for the Centenary celebrations of the Baltimore and Ohio Railroad (B&O), where its sleek appearance and smooth performance impressed all who witnessed it. The application of pressurised oil lubrication showed its advantages over the largely grease-lubricated American Locomotives, and was even incorporated into a later design for the B&O in 1928. King George V was presented with a brass bell to mark the occasion. The original scheme for the Kings had been to name them after cathedrals, but when the US trip was planned it was felt that a more unmistakably British icon was needed. During planning and construction the engine was dubbed the 'Super-Castle'.

They were engines to be reckoned with, powering the Western Region's crack expresses like the Cornish Riviera Limited up until the end of regular steam hauled express services on the WR.

An interesting fact is that although the railway claimed that the class was built in response to longer and heavier trains, it was several years after its introduction before the platforms at the company's major stations were lengthened to accommodate these trains. The class was restricted to the London-Taunton-Plymouth (via both Bristol and Westbury) and London-Birmingham-Wolverhampton (via Bicester) main lines, and even then, only after bridge strengthening had taken place, due to the engines' large boilers giving them a high axle weight of 22.5 long tons (22.9 t). William Stanier based his LMS Princess Royal Class design on the King Class, but with an enlarged boiler and firebox necessitating a 4-6-2 wheel arrangement.

In 1947 experiments had been made with a four-row high-degree superheater in No. 6022 King Edward III, owing to a decline in the availability of high-calorific South Wales steam coal, on which the GWR had always relied for its good locomotive performance. During the 1948 locomotive exchanges, King Henry VI had performed disappointingly using Yorkshire coal, despite demonstrating the 4-6-0 type's unique sure-footedness when climbing out of Kings Cross, where pacific types were apt to slip alarmingly. After this, four-row superheaters were fitted to the class, and modifications were also made to the draughting arrangement, using No. 6001 King Edward VII as a test-bed. From September 1955 double blast-pipes and chimneys were fitted, initially to No. 6015 King Richard III. Following successful testing the whole of the class was subsequently modified and, as a result, their final years in British Railways ownership saw the very best of their performance, particularly on the steep South Devon banks at Dainton, Rattery, and Hemerdon.

They were all withdrawn in 1962, replaced by the western region's short lived diesel-hydraulic Western locomotives.

Loco specification

Specification - GWR 6000 King Class

Boiler type	Number 12	Boiler maximum dia.	6 feet 0 inches (1.829 m)
Boiler minimum dia.	5 feet 6+1⁄4 inches (1.683 m)	Fire tubes, no. and dia.	171 x 2+1⁄4 inches (57 mm)
Flue tubes, no. and dia.	16 x 5+7⁄8 inches (149 mm)	Superheater tubes, no. and dia.	96 × 1 inch (25 mm)
Boiler pressure	250 psi (1.72 MPa)	Boiler length	16 feet 0 inches (4.88 m)
Area of firegrate	34.3 square feet (3.19 m2)	Heating surfaces, tubes	2,008 square feet (186.5 m2)
Heating surfaces, firebox	194 square feet (18.0 m2)	Heating surfaces, superheater	313 square feet (29.1 m2)

List of King Class locomotives

No.	Name	Date built	Date Double Chimney	Date withdrawn	First shed	Last shed	Notes
6000	King George V	June 1927	December 1956	December 1962	Old Oak Common	Old Oak Common	Shipped to America August 1927 to join in Baltimore & Ohio Centenary celebrations. Presented with bell and cabside medallions. Alfloc water treatment fitted 1954. 1,910,424 miles (3,074,529 km) recorded on withdrawal. Restored by Bulmer's Railway Centre, Hereford. Preserved, National Railway Museum, York
6001	King Edward VII	July 1927	February 1956	September 1962	Old Oak Common	Wolverhampton, Stafford Road	Scrapped at Cox & Danks, Oldbury
6002	King William IV	July 1927	March 1956	September 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury
6003	King George IV	July 1927	July 1958	June 1962	Old Oak Common	Cardiff Canton	Involved with incident at Midgham August 1927 when bogie derailed producing redesign of bogie springing on the whole of 'King' class. Scrapped by Swindon Works
6004	King George III	July 1927	July 1958	June 1962	Plymouth Laira	Old Oak Common	Scrapped by Swindon Works.
6005	King George II	July 1927	July 1956	November 1962	Old Oak Common	Old Oak Common	'Alfloc' water treatment fitted 1954. Scrapped at Cashmore's, Great Bridge.
6006	King George I	February 1928	June 1956	February 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped by Swindon Works.
6007	King William III	March 1928	September 1956	September 1962	Old Oak Common	Wolverhampton, Stafford Road	Severely damaged in Shrivenham collision 15 January 1936 and condemned 5 March 1936. Replacement 6007 King William III built March 1936 using some parts of the original engine. 'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury
6008	King James II	March 1928	December 1958	June 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped by Swindon Works.
6009	King Charles II	March 1928	May 1956	September 1962	Old Oak Common	Old Oak Common	'Alfloc' water treatment fitted 1954. Scrapped at Cashmore's, Newport.
6010	King Charles I	April 1928	March 1956	June 1962	Plymouth Laira	Cardiff Canton	Scrapped by Swindon Works.
6011	King James I	April 1928	March 1956	December 1962	Old Oak Common	Old Oak Common	'Alfloc' water treatment fitted 1954. 1,718,295 miles (2,765,328 km) recorded on withdrawal. Scrapped by Swindon Works.
6012	King Edward VI	April 1928	February 1958	September 1962	Newton Abbot	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury
6013	King Henry VIII	May 1928	June 1956	June 1962	Old Oak Common	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped by Swindon Works
6014	King Henry VII	May 1928	September 1957	September 1962	Newton Abbot	Wolverhampton, Stafford Road	Fitted with streamlining from March 1935, but all removed by January 1943 except for 'v'-shaped cab. 'Alfloc' water treatment fitted 1954. 1,830,386 miles (2,945,721 km) on withdrawal. Scrapped at Cox & Danks, Oldbury
6015	King Richard III	June 1928	September 1955	September 1962	Old Oak Common	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury.
6016	King Edward V	June 1928	January 1958	September 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury
6017	King Edward IV	June 1928	December 1955	July 1962	Old Oak Common	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury
6018	King Henry VI	June 1928	March 1958	December 1962	Plymouth Laira	Cardiff Canton	Re-instated to work last King journey under BR from Birmingham via Southall to Swindon. Scrapped by Swindon Works
6019	King Henry V	July 1928	April 1957	September 1962	Wolverhampton, Stafford Road	Wolverhampton, Stafford Road	Scrapped at Cashmore's, Newport.
6020	King Henry IV	May 1930	February 1956	July 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury.
6021	King Richard II	June 1930	March 1957	September 1962	Old Oak Common	Old Oak Common	Scrapped at Cashmore's, Newport.
6022	King Edward III	June 1930	May 1956	September 1962	Plymouth Laira	Wolverhampton, Stafford Road	'Alfloc' water treatment fitted 1954. Scrapped at Cox & Danks, Oldbury.
6023	King Edward II	June 1930	June 1957	June 1962	Newton Abbot	Old Oak Common	Acquired by Woodham's, Barry in December 1962. One pair of driving wheels deliberately cut to enable shunting within the scrap yard. Sold to Brunel Trust, Bristol Temple Meads and left as the 159th departure from Barry December 1984. After protracted preservation (with new driving wheels having been cast; the only steam locomotive in preservation to have received such treatment), the locomotive was restored and entered traffic with an official launch ceremony at Didcot on 2 April 2011.
6024	King Edward I	June 1930	March 1957	June 1962	Plymouth Laira	Cardiff Canton	Acquired by Woodham's, Barry in December 1962. Sold to Quainton Road, Bucks and left as the 36th departure from Barry March 1973. Preserved, owned and operated by the 6024 Preservation Society.
6025	King Henry III	July 1930	March 1957	December 1962	Old Oak Common	Old Oak Common	Scrapped by Swindon Works.
6026	King John	July 1930	March 1958	September 1962	Old Oak Common	Old Oak Common	Scrapped by Swindon Works.
6027	King Richard I	July 1930	August 1956	September 1962	Old Oak Common	Wolverhampton, Stafford Road	Scrapped at Cox & Danks, Oldbury.
6028	King George VI	July 1930	January 1957	November 1962	Old Oak Common	Cardiff Canton	Originally built as King Henry II, renamed January 1937. 1,663,271 miles (2,676,775 km) at withdrawal. Scrapped at Bird's, Newport. Involved in Norton Fitzwarren rail crash (1940); severely damaged but repaired.
6029	King Edward VIII	August 1930	December 1957	July 1962	Old Oak Common	Old Oak Common	Originally built as King Stephen, renamed May 1936. Scrapped at Cashmore's, Newport

Preservation

King Edward II on the Mid-Norfolk Railway

Due to its previous Broad gauge system, the GWR resultantly had the largest loading gauge of all the pre-nationalisation railays. To allow for maximum power creation and resultant speed, the GWR designed the King class to its maximum mainline loading gauge specification, specifically a maximum height allowance of 13 feet 5 inches (4.09 m). This resultantly restricted them as to where they could operate under both GWR and British Railways ownership.

Developments in high-speed rail from the 1970s mean that ballast depths have increased, resulting in a present decrease in UK pan-network loading gauge height. This has recently started to be reversed with the introduction of pan-European loading gauge standards on some mainlines, mainly originating from ports. The present result of these civil engineering changes is that an original height King locomotive would not pass through various points of the modern Network Rail system, designed to a loading gauge height of 13 feet 1 inch (3.99 m).

Faced with a choice of either not operating their locomotives on the mainline or modifying to allow them to pass within the current restricted UK loading gauge, private societies choose to reduce the height of their locomotives by 4 inches (100 mm) by: reducing cab and chimney height; modifying some upper pipe work. The National Railway Museum, owners of 6000 King George V, decided to keep this locomotive in its original condition. This would restrict it to routes which have the original GWR loading gauge, resulting in its present status peserved as a static exhibit only.

Number	Image	Name	Owner	Current location	Current status
6000		King George V	National Railway Museum	NRM York	On static display. Only original height King
6023		King Edward II	Great Western Society	Didcot Railway Centre	Operational
6024		King Edward I	Jeremy Hosking	West Somerset Railway	Operational. Main line certificate expires March 2012, with overhaul scheduled to take place at the West Somerset Railway

Gallery

• 
  AutoCAD drawing of a GWR King
• 
  6026 King John outside Swindon shed 1954
• 
  6000 King George V at Swindon
• 
  6000 King George V at National Railway Museum, York

Sources

• Haresnape, Brian (1978). Collett & Hawksworth Locomotives: A Pictorial History. Shepperton: Ian Allan. ISBN 0 7110 0869 8. {{cite book}}: Invalid |ref=harv (help)
• Whitehurst, Brian (1973). Great Western Engines, Names, Numbers, Types and Classes (1940 to Preservation). Oxford, UK: Oxford Publishing Company. pp. 55, 103, 145. ISBN 978-0-9028-8821-0. OCLC 815661.
• Nock, O.S. (1980). The GWR Stars, Castles and Kings (Omnibus edition). London: Book Club Associates. {{cite book}}: Invalid |ref=harv (help)

External links

• Great Western Society pages on King Class
• King Edward II
• 6024 Preservation Society Ltd