GWR 7 (Armstrong) Class

Armstrong Class
Type and origin
Power type Steam
Designer William Dean
Builder Great Western Railway
Specifications
Configuration 4-4-0
Gauge 4 ft 8 12 in (1,435 mm)
Leading wheel
diameter
4 ft 1.5 in (1.26 m)
Driver diameter 7 ft 0.5 in (2.15 m)
Wheelbase 23 ft 0 in (7.01 m)
Cylinder size 20 in × 26 in (50.80 cm × 66.04 cm)

The William Dean 7 or Armstrong Class refers to a group of four prototype 4-4-0 double-frame locomotives built at the Swindon Works of the Great Western Railway in 1894.

History

They were nominal renewals of four of Dean's "experimental locomotives", Nos. 7, 8, 14 and 16. Had it not been for the recent derailing of one of his 3001 Class 2-2-2s in Box Tunnel, these engines would probably have been rebuilt as 2-2-2s; in the event they emerged as double-framed four-coupled engines with 7' driving wheels and a front bogie similar to that used on the 3031 Class.

Names

The four locomotives, which with their double-curved running plates were exceptionally handsome, were named as follows:

Use

At the end of the 19th century the four locos ran between London and Bristol, but after about 1910 they were moved to Wolverhampton and worked north from there. Rather later, between 1915 and 1923, all four were rebuilt with 6 ft 8.5 in (2.04 m) driving wheels and Standard No. 2 boilers, and became members of the Flower class.[1] They were renumbered 4169-4172.[2]

References

  1. Nock 1977, p. 80.
  2. le Fleming 1954, pp. G27-G29.

Sources