SNCF 2D2 9100
| Company type | Electric locomotive series |
|---|---|
| Industry | Railway transport |
| Founded | 1950 |
| Headquarters | France |
| Products | Electric locomotives |
The 2D2 9100 series consisted of electric locomotives utilized by SNCF in France, debuting in 1950. These engines were derived from the earlier pre-war en:SNCF 2D2 5500 model and formed part of the post-World War II railway electrification efforts.
Design
This locomotive series represented an evolution of the pre-war 2D2 5500 units constructed for the PO-Midi railway. While maintaining mechanical similarities, the 9100 class featured upgraded electrical components aimed at achieving more refined operational control. It marked the final advancement in rigid-framed electric locomotive design before subsequent models transitioned to bogie configurations.
Tracing back to the Paris-Orléans 2D2 5300E locomotives numbered 501–2 built in 1925, these units employed four traction motors—one per axle—each powered via Buchli drives, a system inspired by Swiss engineering. Compared to other PO electric locomotives such as the 2BB2 400, they were regarded as more dependable. The French adaptation utilized a double-sided Buchli gear on each axle, which minimized wear and torsional stresses relative to the Swiss single-sided design.
Equipped with two pantographs collecting current from an overhead catenary, these locomotives powered four traction motors. Their speed regulation combined series-parallel switching with incremental adjustments through field-weakening resistance circuits. Improvements in motor construction, particularly enhanced compensating windings, enabled finer resistance modulation, significantly reducing jolts during switching to one-fifth of earlier levels and allowing a maximum speed increase up to .
Originally, driver accommodations consisted of simple saddles without proper seats; these were upgraded in 1963 to standing seats incorporating the VACMA 'dead man's pedal' system and further supplemented by jump seats in 1973.
Service history
Following World War II, the electrification expansion along the Paris-Lyon line generated a need for rapid express passenger locomotives. A total of 35 units from this class were manufactured between 1950 and mid-1951, falling short of an initially projected production run of approximately 100. The first locomotive was delivered on March 2, 1950, and the final one on July 31, 1951.
Manufacturing was halted as attention shifted towards Co-Co bogie designs exemplified by the CC 7100, introduced starting in 1952. Drawing inspiration from Swiss high-speed chassis such as the and , these bogie-equipped locomotives ultimately supplanted the rigid-framed 2D2 9100 series over three decades later, confirming bogie designs as suitable for express service.
In their later operational phase, the 2D2 locomotives were assigned primarily to freight duties based at . The withdrawal process commenced in 1982 and concluded with full retirement by 1987.
Preservation
One preserved example, unit 2D2 9135—the final locomotive built in this class—is recognized as a monument historique by the AFCL association and has been kept at the depot since 2014.
Another preserved unit, 2D2 9134, was once maintained at Saint-Étienne but was dismantled in 2008.