Buenos Aires Western 4-6-0 Locomotives in Argentina

Class 695 (Locobase 13021)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 29, p. 220.

Locobase 2720 shows the Vulcan version of this design; it went to the Buenos Aires & Rosario. This is the Baldwin quintet of von Borries cross-compound Ten-wheelers that fulfilled the same order for the BAW. They too had Belpaire fireboxes and in all likelihood were superheated with the Vulcan engines in 1933; see Locobase 9924.

Class unknown (Locobase 9924)

Data from Charles Lake, "A New Two-Cylinder Compound", Loco Prototypes News and Notes, The Model Engineer and Practical Electrician, 12 January 1933, p.30.

This design was a superheated upgrade of the original North British engines that came to the Buenos Aires & Rosario in 1904 (see Locobase 2720) and the BAW engines described in Locobase 13021.

The engines retained their Belpaire fireboxes. In the modification, special attention to the valve travel because, as Lake explained, "A common fault of cross compounds, especially when accompanied by short lap valves, is that about 75 per cent of the total horsepower is developed from the low-pressure side." Believing that the reason for this imbalance lay in the "restricted exhaust opening" on the HP side, which created high back pressure, the engine was reconfigured with valves that had a travel of 5 5/16" and laps of 1 5/16" on the HP and 1 1/2" on the LP sides. Also, increasing the cylinder diameter by 1/2" resulted in a slightly higher compounding ratio.