F.S. Gr. 623 - CAPROTTI

Gr. 623 FS "H0" Scale


Download depliant Gr. 623 FS


Steam Locomotive Gr. 623.323: with Caprotti valve gear steam engine, engine cab with flat roof, oil lamps, 3 axles tender, capacity 12 cubic meters, builder's plate in Black Colour, small wheel of frontal axle: spoke type, steam whistle, steam locomotive in red/black colour, 50ies/60ies Status, Built by : "Ansaldo Sampierdarena".

Steam Locomotive Gr. 623.472: with Caprotti valve gear steam engine, engine cab with flat roof, electric lamps, 3 axles tender, capacity 12 cubic meters, front snow plough, builder's plate in Red Colour, small wheel of frontal axle: full type, air whistle, steam locomotive in red/black colour, 50ies/60ies Status, Built by : "Costruzioni Meccaniche Saronno".

FS 623 Group

The Franco-Crosti heater system was applied to five express trains and fast steam locomotives, the 683 FS prototypes turned out World War II . After this system was applied also to the freight train service with the FS 740 Group giving rise to famous group FS 743. After the success of these applications, it was decided to transform some locomotives for passenger train of group Gr. 625 with low traffic on railways where the reduction in operating costs, achieved by the over heater, would be even more important.

It was decided to transform 35 steam locomotives, between 1952 and 1953, from a large group of FS 625 Group ( originally in the 1952 were 341 units) uniformly distributed throughout the territory.

Only 25 machines of these 625 FS were with the original distribution Walschaerts.

Other 10 steam locomotives derived from the Group 600 FS and were transformed into FS 625 Gr. with distribution Caprotti already rebuilt between 1929 and 1933 providing them at the time of a generating superheated steam and a twin cylinder engine instead of the original compound and Caprotti distribution system valves

The power increased from 800 hp of Gr. 625 to 920 hp of the Gr. 623.

The transformation also entailed a change in the pipers of smoke, water and steam and big changes to the boiler tube. Compared with the 625 Gr. , the ratio of warming surface and the heating surface was increased by 38%.

The water supply was carried out with a pump system Nielebock-Knorr.

Such machines were not widely used or were used only for secondary lines. In this way the effects of transformation were not fully exploited.

The last units Gr. 623 with distribution Walschaerts were eliminated in the 1972.

The text of this paper and technical data are taken from the book Steam Locomotive - New 1998 edition of"Giovanni Cornolò", Edizioni Ermanno Albertelli Editore Address : G.S. Sonnino, 34 – PARMA – ITALY



Gr. 623 FS Caprotti valve gear steam engine


Gr. 623 FS Caprotti valve gear steam engine