GWR 3100 Class

The Great Western Railway (GWR) 3100 Class was a class of 2-6-2T side tank steam locomotive.

This article is about the 5 locomotives rebuilt in 1938/9 from the 3150 Class. For the 40 locomotives built in 1903–06 as the 3100 class, see GWR 5100 Class.

GWR 3100 Class
Type and origin Power type Steam Designer Churchward (rebuilt by Collett) Builder GWR Swindon Works Order number Lot 319 Build date 1906 Rebuild date 1938 Number rebuilt 5
Specifications Configuration: ​  • Whyte 2-6-2T  • UIC 1'C1 h2t Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Leading dia. 3 ft 0 in (0.914 m) Driver dia. 5 ft 3 in (1.600 m) Trailing dia. 3 ft 8 in (1.118 m) Minimum curve 6 chains (396 ft; 121 m) normal, 5 chains (330 ft; 101 m) slow Length 41 ft 0 in (12.50 m) over buffers Width 8 ft 11+1⁄4 in (2.724 m) Height 13 ft 2 in (4.013 m) Axle load 19 long tons 3 cwt (42,900 lb or 19.5 t) (21.4 short tons) full Adhesive weight 57 long tons 6 cwt (128,400 lb or 58.2 t) (64.2 short tons) full Loco weight 81 long tons 9 cwt (182,400 lb or 82.8 t) (91.2 short tons) full Fuel type Coal Water cap. 2,000 imp gal (9,100 L; 2,400 US gal) Firebox: ​  • Grate area 20.56 sq ft (1.910 m2) Boiler GWR Standard No. 4 Boiler pressure 225 lbf/in2 (1.55 MPa) Heating surface: ​  • Firebox 128.72 sq ft (11.958 m2)  • Tubes 1,349 sq ft (125.3 m2) Superheater: ​  • Type 4-element or 6-element  • Heating area 4-element: 136.64 sq ft (12.694 m2), 6-element: 181.10 sq ft (16.825 m2) Cylinders Two, outside Cylinder size 18.5 in × 30 in (470 mm × 762 mm)
Performance figures Tractive effort 31,170 lbf (138.7 kN)
Career Operators GWR » BR Class 3100 Power class GWR: D, BR: 4MT Numbers 3100–3104 Axle load class GWR: Red Withdrawn 1957–1960 Disposition All scrapped

History

This class of large prairie was created in 1938 when Collett rebuilt some of Churchward's 3150 Class engines for use as bankers, particularly from Severn Tunnel Junction shed. These engines used the same standard class 4 boiler, but with pressure increased to 225 psi (1,550 kPa) and smaller 5 feet 3 inches (1.600 m) driving wheels and a one-half inch (13 mm) increase in cylinder diameter. This raised their tractive effort to 31,170 pounds (14,140 kg). Almost unnoticeable was a 2 in (50.8 mm) reduction in pony truck wheel diameter to 3 ft 0 in (914 mm). Only five engines were ever modified, Nos. 3173, 3156, 3181, 3155 and 3179 which were rebuilt as 3100 to 3104 respectively. All members of the class were scrapped.

See also

• GWR 3100/5100 Class (1906)
• GWR 3150 Class
• GWR 5101 Class
• GWR 6100 Class
• GWR 8100 Class
• List of GWR standard classes with two outside cylinders

References

• Whitehurst, Brian (1973). Great Western Engines, Names, Numbers, Types and Classes (1940 to Preservation). Oxford, UK: Oxford Publishing Company. pp. 30, 102, 135. ISBN 978-0-9028-8821-0. OCLC 815661.

External links

• Class 3100 Details at Rail UK