Alta Italia 4-6-0 Locomotives in Italy

Class Vittorio Emanuele II/Gr 650 (Locobase 2476)

Data from Titre Exposition universelle internationale de 1889 a Paris. Rapports du jury internationale. Auteur - Volume France. Ministere du Commerce, de l'industrie. Picard, Alfred, ed. Volume Groupe VI - -Outillage et precedes des industries mecaniques. Electricite (5e partie) Classes 60 a 63. Rapport sur le materiel des chemins de fer; tables pp. 194-195. ([] (accessed 1 September 2005); and "FS Class 650" in Wikipedia at ([], last accessed 4 July 2019) and [] is also a source of data, primarily for the weights and wheelbases. See also "Passenger Locomotive: Upper Italian Railways", Enginering, Volume 38 (11 July 1884), pp. 31-32; and "An Italian Ten-wheel Locomotive", Railroad and Engineering Journal, Volume 64, No 4 (April 1890), pp. 173-174.

One of those rare engines in which a link motion's large eccentrics and link are carried outside of the drivers; the Gooch motion is a variant of the Stephenson valve gear that puts the hub of the eccentrics on a return crank. Brian Hollingsworth (1982) observes that these very successful engines also featured one of the very first uses of a combustion chamber. Built by Ansaldo (Genoa), Miani & Silvestri (Milan), and Maffei (Munich).

The prototype was designed by Cesare Frescot of the Alta Italia and was produced by the SFAI's Turin shops. Almost immediately, the SFAI merged with the Mediterraneo with the latter's name being preserved. Ansaldo manufactured 36 for the RM, Maffei 13, and Officine Miani & Silvestri 5. Comendatore Frescot designed this engine to work the Genoa-Alessandria passenger and heavy freights. The requirements included an average speed of 31 mph over a profile that included one 14-mile grade with a ruling ascent of 1 3/4%.

Wikipedia claims that Frescot chose to use a round-top firebox instead of SFAI's usual Belpaire design. The round top, Wikipedia continues, "would be a mainstay of Italian locomotive practice." (On the other hand, 19th century sources reported that the boiler had a Belpaire firebox. It's possible that the Miani & Silvestri locomotives--described in the 1889 tables--had both the combustion chamber and a Belpaire firebox.)

Of more general note, the Vittorio Emmanuele II was the first class to use the Ten-wheeler arrangement in continental Europe.

The bogie had a very short wheelbase, which meant the cylinders were located between the bogie and the first driven axle. Consequently, the steam pipes led back from the boiler smokebox to the valve chests.

Tutto Treno shows seven different variants, although the diagrams give no indication other than weight differences why there were seven. Locobase suspects that many of the variations arose from their construction by different builders.

The Jury report notes that the locomotives were built for the new grade at Giovi, which had recently been reduced from a ruling grade of 1.6% to 1.2%. The 650s were intended to pull 140 metric tons(154 short tons) over that line.

As was often true with first designs in locomotives, however, the design had its shortcomings chiefly because it received a third driving axle to increase adhesion weight without exceeding axle loadings. It wasn't long before heavier traffic forced the use of more powerful locomotives. The last was retired in the 1920s.

Taken out of service by 1914 when the Giovi line was electrified.