GWR 4700 Class

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GWR 4700 Class
GWR 4700 Class 2-8-0 4706.jpg
GWR Class 4700 2-8-0 4706 at Old Oak Common MPD, London, on 15 December 1963
Type and origin
Power type Steam
Designer George Jackson Churchward
Builder GWR Swindon Works
Order number Lots 214, 221
Serial number 4700: 2866,
4701–4708: none
Build date 1919 (1), 1922–1923 (8)
Total produced 9
Specifications
Configuration 2-8-0
UIC classification 1'D h2
Gauge 4 ft 8 12 in (1,435 mm)
Leading wheel
diameter
3 ft 2 in (0.965 m)
Driver diameter 5 ft 8 in (1.727 m)
Minimum curve 8 chains (530 ft; 160 m) normal,
7 chains (460 ft; 140 m) slow
Length 66 ft 4 14 in (20.22 m)
Width 8 ft 11 in (2.72 m)
Height 13 ft 4 34 in (4.08 m)
Axle load 19 tons 12 cwt (43,900 lb or 19.9 t) full
Weight on drivers 73 tons 8 cwt (164,400 lb or 74.6 t) full
Locomotive weight 82 tons 0 cwt (183,700 lb or 83.3 t) full
Tender weight 46 tons 14 cwt (104,600 lb or 47.4 t) full
Fuel type Coal
Water capacity 4,000 imperial gallons (18,000 l; 4,800 US gal)
Boiler pressure 225 lbf/in2 (1.55 MPa)
Firegrate area 30.28 sq ft (2.813 m2)
Heating surface:
– Tubes
2,062.35 sq ft (191.599 m2)
– Firebox 169.75 sq ft (15.770 m2)
Superheater type 4-element or 6-element
Superheater area 4-element: 211.20 sq ft (19.621 m2),
6-element: 276.98 sq ft (25.732 m2)
Cylinders Two, outside
Cylinder size 19 in × 30 in (483 mm × 762 mm)
Valve gear Stephenson
Valve type Piston valves
Performance figures
Tractive effort 30,460 lbf (135.5 kN)
Career
Operator(s) GWR » BR
Class 4700
Power class GWR: D,
BR: 7F
Number(s) 4700–4708
Axle load class GWR: Red
Withdrawn 1962–1964
Disposition All scrapped

The Great Western Railway (GWR) 4700 Class was a class of nine 2-8-0 steam locomotives, numbered 4700 through 4708. They were the final locomotives designed by George Jackson Churchward and were introduced in 19191921 for fast goods work. Although built for freight, the class sometimes hauled passenger trains, notably heavy holiday expresses in the summer.

History[edit]

The 4700 Class was intended for a quite different role than the 2800 Class. The 2800s were small-wheeled mineral haulers with 4 ft 7½ in driving wheels. The 4700s had 5 ft 8 in driving wheels - the intermediate of Churchward's three standard wheel sizes, and were intended for express goods trains.

Accidents and incidents[edit]

  • On 12 November 1958, locomotive No. 4707 was hauling a freight train when it overran signals and was derailed at Highworth Junction, Swindon, Wiltshire. A newspaper train collided with the wreckage.[1]

Boilers[edit]

The prototype, No. 4700, was constructed in 1919. It was built with a Standard No. 1 boiler as the intended design of a larger boiler, the Standard No. 7, was not yet ready.[2] 4700 was converted to the Standard No. 7 when it was available, and the rest of the class was built with them.

No. 4707 at Swindon Works 25 April 1954

Withdrawal[edit]

Withdrawals began in June 1962 with No.4702, while the last were removed from service in May 1964. No.4705 recorded the greatest distance travelled, at 1,656,564 miles.

Preservation[edit]

No members of the class were preserved. However, the Great Western Society made the decision to create the next locomotive in the sequence, 4709. Supported via a GWS sub-group, it is being built using a mixture of new parts and others recycled from former Barry scrapyard locomotives:

  • GWR 5101 class 2-6-2T 4115 - six of the eight driving wheels and the frame extension.[3]
  • GWR 2800 class 2-8-0 2861 - the cylinder block.
  • GWR 5205 class 2-8-0T 5227 - the axleboxes, horns, fourth axle (axle only) and other various components.

The plates for the new frames were cut and machined in 2012, and 4709 is now under construction at Llangollen, alongside other new-build projects 6880 Betton Grange and 45551 The Unknown Warrior.

References[edit]

  1. ^ Trevena, Arthur (1980). Trains in Trouble. Vol. 1. Redruth: Atlantic Books. p. 47. ISBN 0-906899-01-X. 
  2. ^ Cook, K.J. (1974). Swindon Steam. Ian Allan. 
  3. ^ The 5199 Project (2011). "5199 Project". 5199.co.uk. Retrieved 2011-07-25. 

External links[edit]