Somerset & Dorset Joint 2-8-0 Locomotives in Great_Britain

Class 7F/ G9AS (Locobase 3658)

Data from "New Consolidation Mineral Engine, Somerset & Dorset Joint Ry", Locomotive Magazine, Volume XX [20], No 260 (15 April 1914), p. ; and "Mineral Engines for the Somerset & Dorset Joint Ry", Locomotive Magazine, Volume XX [20], No 261 (15 May 1914), p.

Powerful Consolidation designed by Henry Fowler and first put into service just before World War I. Although smaller in boiler size and lighter on the drivers than most British 2-8-0s, this engine generated a higher tractive effort. It had a relatively large firebox area and good-sized superheater.

The [] link from the West Somerset Railway's link gives a detailed history of this class. "The locomotives were the first on the S&D to have outside cylinders and Walschaerts valve gear," says the history. "The cylinders were inclined at 1 in 12, to clear the platform edges. ...The locomotives were amongst the most powerful in the country at the time."

A later (1925) batch -- 86-90 -- had larger boilers fitted with 146 1 3/4" small tubes and 21 5 1/8" flues and and show a Belpaire firebox with 190.7 sq ft of direct heating surface. The grate area did not change.