Fiat Materfer 7131
| Industry | Rail transport manufacturing |
|---|---|
| Founded | 1958 |
| Headquarters | Córdoba , Argentina |
| Products | Diesel multiple unit trains (7131 series) |
The 7131 represented a class of Argentine diesel multiple units initially manufactured in Italy by Fiat Ferroviaria, with subsequent production licensed to the Argentine firm Materfer. Launched during the 1960s, these railcars were introduced to replace outdated rolling stock on key metropolitan lines including Roca, Urquiza, Mitre, and Sarmiento.
Following the privatization of Argentina's railways in the early 1990s, the 7131 series was gradually withdrawn and succeeded by newer light rail models also produced by Materfer. They were popularly known by the nickname Chanchas (meaning Piggies in Spanish).
Background
In 1958, Argentina’s Ministry of Transport entered into a contract with Fiat Ferroviaria to purchase 210 new diesel railcars. Each consisted of two connected cars powered by a FIAT diesel engine generating 660 HP, enabling maximum speeds up to 115 km/h. Their lightweight construction allowed operation across diverse railway lines, and having driving cabins at both ends reduced turnaround time at terminal stations, improving operational efficiency for urban transit.
At that period, the Mitre and Sarmiento lines were still using obsolete Drewry Car Co. railcars dating back to the 1930s, which were insufficient for increasing passenger volumes, creating a demand for modern replacements such as the 7131 units.
Production
Manufacturing took place at FIAT facilities in Turin, Decauville, and Córdoba. While early batches were produced in Italy and France, most units were assembled domestically at Materfer’s plant in Ferreyra, Córdoba, a facility specifically established for this production.
The 7131 design was inspired by the 1934 Pioneer Zephyr, a diesel train developed by the Budd Company for the Chicago, Burlington and Quincy Railroad (CB&Q). The Zephyr was known for its articulated cars supported by Jacobs bogies and extensive use of stainless steel, serving as an emblematic example promoting passenger rail service in the United States.
The initial 7131 units entered service on both standard and broad gauge routes (Roca, Mitre, Urquiza, and Sarmiento lines), with the exception of the San Martín railway, which selected rolling stock from Ganz Works. Early models featured green and ochre paint schemes before transitioning to the official yellow, blue, and red colors of Ferrocarriles Argentinos.
By 1962, FIAT Concord deployed the 7131 on segments of the Mitre Railway between Villa Ballester–Zárate and Victoria–Capilla del Señor, replacing older Ganz railcars that had been operating since 1938. The 7131 also served certain routes in Santa Fe.
On the Roca and Sarmiento lines, these units substituted aging coaches from Drewry, Birmingham, and Armstrong Whitworth across multiple suburban branches such as Temperley–La Plata–Cañuelas; Haedo–José Mármol; Merlo–Lobos; Pereyra–Ensenada; La Plata–Pipinas–Atalaya–Magdalena; Moreno–Luján–Mercedes; Lobos–Navarro. Additionally, they operated on longer-distance routes including Bahía Blanca–Darregueira–Carmen de Patagones and Constitución–Tandil–Necochea, covering large portions of southern and western Buenos Aires Province.
Decline
By the 1990s, the operation of the 7131 railcars was confined to a few local routes such as Temperley–Haedo, La Plata–Río Santiago, Merlo–Lobos, and Villa Ballester–Zárate. Due to neglect by Ferrocarriles Argentinos, the fleet experienced severe deterioration, with numerous units frequently suffering damage or being destroyed by fire, which significantly diminished the number of functional vehicles.
After Argentina's railway privatisation, the 7131 series was considered outdated and subsequently replaced by newer Materfer models. The last route employing 7131 units was the Victoria–Capilla del Señor line on the Mitre railway. The concessionaire for the Mitre Line, Trenes de Buenos Aires, procured eight new Materfer railcars, colloquially known as Pitufos ("Smurfs") because of their compact size. Nevertheless, their limited passenger capacity and inadequate suspension meant that many 7131 units continued to be used.
A cooperative named "Ferroser" suggested reopening the Ringuelet-Brandsen route using 7131 railcars, but this initiative never came to fruition.
In 2008, there was a brief resurgence when the defunct company Trenes Especiales Argentinos refurbished a 7131 unit to operate the Gran Capitán service between F. Lacroze station and Posadas in Misiones.