2-4-0+0-4-2

In the Whyte notation for the classification of steam locomotives by wheel arrangement, the 2-4-0+0-4-2 is an articulated locomotive, usually of the Garratt type. The wheel arrangement is effectively two 2-4-0 locomotives operating back to back, with the boiler and cab suspended between the two power units. Each power unit has two leading wheels on one axle, four powered and coupled driving wheels on two axles, and no trailing wheels. Since the 2-4-0 type is sometimes known as a Porter, the corresponding Garratt type could be referred to as a Double Porter. A similar wheel arrangement exists for Mallet locomotives, but is referred to as 2-4-4-2.

Other equivalent classifications are:

• UIC classification: 1B+B1 (also known as German and Italian classifications)
• French classification: 120+021
• Turkish classification: 23+23
• Swiss classification: 2/3+2/3 up to the early 1920s, later 4/6

Overview

This was the second rarest Garratt wheel arrangement. Only five locomotives were constructed to this arrangement, four of which were built by Beyer, Peacock (BP).

The four BP locomotives comprised three for the 5 ft 3 in (1,600 mm) São Paulo Railway of Brazil in 1915, and one for the 2 ft 6 in (762 mm) gauge Ceylon Government Railway (CGR) in 1929, the CGR’s class H1.

One more was built in 1919 by the São Paulo Railway, for its own use on 1,000 mm (3 ft 3+3⁄8 in) metre gauge.

2-4-0+0-4-2 Garratt production list – All manufacturers

Gauge	Railway	Class	Works no.	Units	Year	Builder
2 ft 6 in	Ceylon Government Railway	H1	6629	1	1929	Beyer, Peacock
1,000 mm	São Paulo Railway, Brazil			1	1919	São Paulo Railway
5 ft 3 in	São Paulo Railway, Brazil	Q	5892-5894	3	1915	Beyer, Peacock