GWR 9400 Class

Great Western Railway 9400 class

9466 is one of two preserved members of the 210-strong class. Its Great Western Railway livery is inauthentic as it was one of those built for British Railways after nationalisation.

Type and origin Power type Steam Builder Swindon Works (10) R. Stephenson & Hawthorns (100) W. G. Bagnall (50) Yorkshire Engine Company (50) Order number GWR Lot Nos. 365, 382–387 Serial number RSH: 7450–69, 7547–96, 7611–40 WGB: 2910–2959 YEC: 2443–72, 2544–53, 2575–84 Build date 1947–1956 Total produced 210

Specifications Configuration: ​  • Whyte 0-6-0PT  • UIC C h2t (10) C n2t (200) Gauge 4 ft 8 1⁄2 in (1,435 mm) standard gauge Driver dia. 4 ft 7 1⁄2 in (1.410 m) Minimum curve 5 chains (330 ft; 100 m) normal, 4.5 chains (300 ft; 91 m) slow Wheelbase 15 ft 6 in (4.72 m) Length 33 ft 2 in (10.11 m) over buffers Width 8 ft 7 in (2.616 m) Height 12 ft 5 1⁄2 in (3.797 m) Axle load 19 long tons 5 cwt (43,100 lb or 19.6 t) (21.6 short tons) full Loco weight 55 long tons 7 cwt (124,000 lb or 56.2 t) (62.0 short tons) full Fuel type Coal Water cap 1,300 imp gal (5,900 l; 1,600 US gal) Firebox:  • Firegrate area 17.40 sq ft (1.617 m2) Boiler pressure 200 lbf/in2 (1.38 MPa) Heating surface 1,347 sq ft (125.1 m2)  • Tubes 1,245.7 sq ft (115.73 m2)  • Firebox 101.7 sq ft (9.45 m2) Cylinders Two, inside Cylinder size 17 1⁄2 in × 24 in (444 mm × 610 mm)

Performance figures Tractive effort 22,515 lbf (100.15 kN)

Career Operators Great Western Railway Western Region of British Railways Class 9400 or 94XX Power class GWR: C BR: 4F Numbers 9400–9499, 8400–8499, 3400–3409 Axle load class GWR: Red Withdrawn 1959–1965 Preserved 9400, 9466 Disposition Two preserved, remainder scrapped

The Great Western Railway (GWR) 9400 Class is a class of 0-6-0 pannier tank steam locomotive, used for shunting and banking duties.

The first ten 9400s were the last steam engines built by the GWR. After nationalisation in 1948, another 200 were built by private contractors for British Railways (BR). Most had very short working lives as the duties for which they were designed disappeared through changes in working practices or were taken over by diesel locomotives. Two locomotives survived into preservation, one as part of the National Collection.

The 9400 class was the final development in a long lineage of tank locomotives that can be directly traced to the 645 Class of 1872. Over the decades details altered, the most significant being the adoption of Belpaire fireboxes necessitating pannier tanks.

The 9400 resembled a pannier tank version of the 2251 class, and indeed shared the same boiler and cylinders as the 2251, but was in fact a taper-boilered development of the 8750 subgroup of the 5700 class. The advantage was a useful increase in boiler power, but there was a significant weight penalty that restricted route availability. The 10 GWR-built locomotives had superheaters but the remainder did not.

The first ten 9400s were built by the Great Western and were the last steam engines built by the company. After the nationalisation of Britain's railways in 1948, private contractors built another 200 for British Railways.

The 9400s were numbered 9400–9499, 8400–8499 and 3400–3409. BR gave them the power classification 4F.