4-6-2 Class 8P Merchant Navy rebuilt SR Profile and Models

The SR Merchant Navy 4-6-2s were a class of steam locomotive with an unusual air-smoothed casing, designed for use on the Southern Railway network by Oliver Bulleid. The design incorporated a number of new developments in British steam technology, with the locos featuring the use of welding in the construction process (one of the first in the UK), thermic syphons within the boiler and Bulleid’s controversial chain-driven valve gear. Named after Merchant Navy shipping lines, the locos also earned several enthusiast nicknames such as “Spam Cans” and “Packets”, due to their unique design. Due to problems with some of the more novel features of their design, all members of the class were modified in the 1950s and lost their air-smoothed casing in the process.

Type of Locomotive

Steam

Builder

SR Eastleigh Works

Build Date

1941-1949

Total Built

30

Tractive Effort

37,515 lbf
(later reduced to 33,495 lbf)

Wheel Configuration

4-6-2

Operated By

Southern Railway
British Railways

Main Duties

Express Passenger

In Service Until

1967

Surviving Locos

10 preserved, 1 sectioned (all surviving locos modified)