Alsace-Lorraine S 12

S 12 (Alsace-Lorraine) SNCF 1-231
Numbering:	REL 1301-1308 SNCF 1-231 A 301-304, 306-308
Number:	8th
Manufacturer:	Grafenstaden
Year of construction (s):	1908 ff
Retirement:	1951
Type :	2'C1 'h4v
Gauge :	1435 mm ( standard gauge )
Length over buffers:	21,500 mm
Service mass:	82.2 t
Friction mass:	48.0 t
Top speed:	100 km / h
Indexed performance :	1,214 kW
Driving wheel diameter:	2,040 mm
Impeller diameter front:	950 mm
Rear wheel diameter:	1,400 mm
Cylinder diameter:	2 × 380/600 mm
Piston stroke:	660 mm
Boiler overpressure:	15 bar
Grate area:	3.22 m²
Superheater area :	38.50 m²
Evaporation heating surface:	200.21 m²
Tender:	2'2 'T 21.5
Water supply:	21.5 m³
Brake:	Air brake

The vehicles of type S 12 of the Reichseisenbahnen in Alsace-Lorraine were express locomotives with the wheel arrangement 2'C1 '( Pacific ). They were initially called the S 6 and were among the first Pacific locomotives in Europe.

Due to the boiler pressure of 15 bar and in order to be able to limit the length for a 20 m turntable, they had a long, narrow fire box between the drive wheels . The four-cylinder compound engine corresponded to the de Glehn type ; the external high-pressure cylinders were located close to the drive wheels and worked on the central coupling axle, the internal low-pressure cylinders on the cranked first coupling axle.

However, the boiler was too small for this locomotive; in addition, the superheater was quite small. Since the vehicles of type S 10 from Prussia and the southern German Pacifics Bayerische S 3/6 and Badische IV f were more powerful, only eight copies were made.

The locomotive with the number 1305 was lost in the First World War in 1918, the others stayed in France, where they came to the SNCF in 1938 as 1-231 A 301 to 308 (without 305) . The last locomotive, the 1-231 A 301, was retired in 1951.

The locomotives received Schlepptender the type 2'2 'T 21.5.