GWR 3800 Class

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GWR 3800 'County' Class
GWR 3818 County of Radnor (Boys' Book of Locomotives, 1907).jpg
3818 County of Radnor
Specifications
Power type Steam
Designer George Jackson Churchward
Builder Swindon Works, Great Western Railway
Order number 149, 165, 184
Serial number 2056–65, 2209–28, 2415–25
Build date 1904, 1906, 1911–12
Total produced 40
Configuration 4-4-0
Gauge 4 ft 8 12 in (1,435 mm)
Leading wheel
diameter
3 ft 2 in (965 mm)
Driver diameter 6 ft 8 12 in (2,045 mm)
Wheelbase 24 ft 0 in (7,315 mm)
Axle load 18.15 long tons (18.44 t)
Weight on drivers 34.3 long tons (34.85 t)
Locomotive weight 55.3 long tons (56.19 t)
Tender weight 36.75 long tons (37.34 t)
Locomotive and tender
combined weight
92.05 long tons (93.53 t)
Fuel type Coal
Water capacity 3,000 imp gal (13,638 L)
Boiler Standard No. 4
Boiler pressure 200 psi (1,379 kPa)
Firegrate area 20.56 sq ft (1.91 m2)
Heating surface:
– Tubes
1,689.82 sq ft (156.99 m2)
– Firebox 128.30 sq ft (11.92 m2)
– Total 1,818.12 sq ft (168.91 m2)
Cylinders 2, outside
Cylinder size 18in diameter x 30in stroke
Valve gear Stephenson
Tractive effort 20,530 lbf (91 kN)
Career
Railroad(s) Great Western Railway
Class 3800
Power class GWR: C
Number in class 40
Number 3473–82, 3801–30 until Dec 1912
3800–39 from December 1912
Official name County
Nicknames Churchward's Rough Riders
Axle load class GWR: Red
Withdrawn 1930–33
Disposition All scrapped
Dimensions as built[1]

The Great Western Railway County Class were a class of 4-4-0 steam locomotives for express passenger train work introduced in 1904 in a batch of ten. Two more batches followed in 1906 and 1912 with minor differences. They were designed by George Jackson Churchward, who used standard components to produce a four-coupled version of his Saint Class 4-6-0s.

Construction[edit]

The first locomotive, no. 3473 County of Middlesex, was built at Swindon Works in May 1904, with the following nine completed by October 1904.[2] They were initially fitted with parallel-sided copper-capped chimneys, which were soon replaced by tapered cast iron chimneys.[3] The second batch, of twenty, were built between October and December 1906. This batch had tapered cast iron chimneys from the start.[4] A third and last batch of ten were built between December 1911 and February 1912.[5] On these the footplates had curved drop ends at the cab and front bufferbeam.[6] They were also fitted from new with a superheater and top feed.[5] Chimneys were a larger version of the copper-capped type of the first batch.[3] Coupled wheels had independent springing, without the compensating beams fitted between the axleboxes on Churchward's 4-6-0s.[7] The cylinder block, including the piston valves and smokebox saddle, was constructed from two castings from the same pattern, bolted back to back, each casting containing one half of the saddle.[2] The cab, boiler and coupled wheels were attached to plate frames. The cylinder block was carried on two bar frames, bolted to the front end of the plate frames.[7] The piston valves were driven by Stephenson valve gear. The class were fitted with the Standard No. 4 boiler.[2] One locomotive, no. 3805 County Kerry was fitted with a smaller Standard No. 2 boiler between November 1907 and May 1909.[4]

Operation[edit]

They were the last new GWR 4-4-0 design and by far the most modern, with inside frames and outside cylinders. They were designed as a part of Churchward's standardisation plan, but were found to have a front end too powerful for the wheel arrangement and all were withdrawn by the early 1930s. They were designed, in part, for the Hereford to Shrewsbury LNWR line over which the GWR had running powers, but on which they were expressly forbidden to use 4-6-0 locomotives. The 4-4-0 Counties were in effect a shortened GWR 2900 Class, providing engines powerful enough for the trains but with the requisite four coupled wheels.

The key components were all proven but the combination was somewhat unhappy, and perhaps the least successful Churchward design. From the outset they were found to be rough riders but otherwise effective locos. All other GWR 4-4-0s were inside cylindered and none had a piston stroke greater than 26", whereas the 'County' had a 30" stroke driving a meagre 8' 6" wheelbase.

The County Class used the same cylinders and motion as Churchward's six-coupled locomotives, and required the same mass to counterbalance the reciprocating parts of the motion. However the weight required had to be divided between four driving wheels rather than six. The heavier balance weights produced a high level of wheel hammer blow; at 6 revolutions per second the hammer blow was 8 tons, compared with the 3.6 tons of the inside-cylindered City Class and the 6.4 tons of the six-coupled Saint Class. The left hand trailing axleboxes often developed hammering, which was caused by the amount of counterbalancing used.[8]

This class were subject to the 1912 renumbering of GWR 4-4-0 locomotives, which saw the Bulldog class gathered together in the series 3300-3455, and other types renumbered out of that series. The County Class took numbers 3800-3839.

No. 3833 County of Dorset was the first to be withdrawn, in February 1930. By the middle of 1933 all had gone, the last survivor being no. 3834 County of Somerset, withdrawn in November of that year.[9]

County Tank 2221

They were also the basis for the 'County Tank' design, a 4-4-2T using the same basic design as the County but with a smaller and lighter boiler, and the replacement of the tender by the addition of side tanks, bunker and trailing axle.

Numbers Name
First Second (1912)
3473 3800 County of Middlesex
3801 3801 County Carlow
3802 3802 County Clare
3803 3803 County Cork
3804 3804 County Dublin
3805 3805 County Kerry
3806 3806 County Kildare
3807 3807 County Kilkenny
3808 3808 County Limerick
3809 3809 County Wexford
3810 3810 County Wicklow
3811 3811 County of Bucks
3812 3812 County of Cardigan
3813 3813 County of Carmarthen
3814 3814 County of Chester
3815 3815 County of Hants
3816 3816 County of Leicester
3817 3817 County of Monmouth
3818 3818 County of Radnor
3819 3819 County of Salop
3820 3820 County of Worcester
3821 3821 County of Bedford
3822 3822 County of Brecon
3823 3823 County of Carnarvon
3824 3824 County of Cornwall
3825 3825 County of Denbigh
3826 3826 County of Flint
3827 3827 County of Gloucester
3828 3828 County of Hereford
3829 3829 County of Merioneth
3830 3830 County of Oxford
3474 3831 County of Berks
3475 3832 County of Wilts
3476 3833 County of Dorset
3477 3834 County of Somerset
3478 3835 County of Devon
3479 3836 County of Warwick
3480 3837 County of Stafford
3481 3838 County of Glamorgan
3482 3839 County of Pembroke

Models[edit]

Hornby Railways manufacture a model of the 38xx in OO gauge. 3mm Scale Model Railways manufacture a model kit of the 38xx in TT gauge.

References[edit]

  1. ^ le Fleming 1962, pp. J10-J12
  2. ^ a b c Nock 1978, p. 14
  3. ^ a b Harewood 1993, p. 56
  4. ^ a b Nock 1978, p. 15
  5. ^ a b Nock 1978, p. 38
  6. ^ Holcroft 1971, p. 102
  7. ^ a b Nock 1978, p. 13
  8. ^ Nock 1978, p. 16
  9. ^ Nock 1978, p. 66

Bibliography[edit]

  • le Fleming, H.M. (February 1962). White, D.E., ed. The Locomotives of the Great Western Railway, part nine: Standard Two-Cylinder Classes. RCTS. 
  • Holcroft, Harold (1971). An Outline Of Great Western Locomotive Practice 1837-1947. Shepperton, Middlesex: Ian Allan. ISBN 0-7110-0228-2. 
  • Haresnape, Brian; Swain, Alec (1976 (reprinted 1993)). Churchward Locomotives: A Pictorial History. Shepperton, Middlesex: Ian Allan. ISBN 0-7110-0697-0. 
  • Nock, O.S. (1977). Standard Gauge Great Western 4-4-0s Part 1 Inside Cylinder Classes 1894-1910. Newton Abbot: David & Charles. ISBN 0-7153-7411-7. 
  • Nock, O.S. (1978). Standard Gauge Great Western 4-4-0s Part 2 Counties to the Close 1904-1961. Newton Abbot: David & Charles. ISBN 0-7153-7684-5. 

External links[edit]