Lourenco Marques 2-8-2 Locomotives in Mozambique

Class 401 (Locobase 14729)

Data from DeGolyer, Vol 72, pp. 386+. Works numbers were 57966-57969 in August 1924.

The boiler and firebox as well as the weights, engine wheelbase, and tender on this Mikado quartet duplicated the 301-class Pacifics that had arrived from Baldwin beginning in 1919 (Locobase 14728). Firebox heating surface area included 15 sq ft (1.4 sq m) in three arch tubes. Piston valves measured 8" (203 mm) in diameter.

Rail weighed a relatively heavy 80 lb/yard (40 kg/metre). The 401s faced minimum curve radii of 200 metres (656 feet) and grades that at most inclined at 1 1/2% and that for only 1,500 metres (0.93 miles). Transvaal coal had an average calorific power that was 83.3% of the best Welsh coal. The 401 was expected to haul a load of 500 short tons (454 metric tons) enter the 1 1/2% grade at 40-45 kph (24.8-28 mph) and maintain a speed of 20 kph (12.4 mph) as it crested.

Experience with the first three guided the production of the latter two. For example, the staybolt holes bored into the firebox plates in the first batch were not in the same line and were "slantwise", advises the spec for the second batch. "[W]ith vibration and work of loads of locos, they break too frequently."

Stresses on the locomotive contributed to the failure of driving spring hangers, so 304-305 were to get stronger ones.