The 448 series electric railcars, originally known as the 444.500 subseries, were a major improvement over the 432 and 444 series as they were able to travel at 160 km/h and allowed the new daily long-distance Intercity service to be extended. With the introduction of the Euromed, Alaris and Talgo 7 trains, these units were gradually moved over to the mid-distance service.
This train has a capacity of 236 seats, plus another for people with reduced mobility and 8 fold down seats, diaphanous, with a standard class and space for bicycles. The seats are ergonomic and are made of fireproof material.
The vehicle is temperature controlled and has double glazed windows with an air chamber. It has two toilets, one of which is adapted for people with reduced mobility.
These vehicles also have an area for people with reduced mobility as well as ambient music, GPS public address, indoor and outdoor display screens and folding tables in the passenger lounges.
The four trains that operate in Long Distance traffic have two classes: First Class and Standard Class, as well as a buffet car.
The trains that formed part of the 444,500 subseries constituted Renfe's third generation of electric trains, and had significant improvements over the previous series (432 and 444), being able to circulate at 160 km/h, and making it possible to provide a new long-distance daytime service product, Intercity trains, characterised by various frequencies and high speeds.
The 31 trains that originally comprised the 444,500 series were subdivided into two subseries. The first subseries, consisting of 11 units, was built by Caf, who also made the engine carriages in the second subseries, with Macosa and Ateinsa (now Alstom) building the trailers. The electrical equipment was supplied by Cenemesa (now Bombardier). Both series were built between 1987 and 1991.
Functionally, they are identical, with small differences in the appearance of the interior (buffet car) and the exterior (end carriages). From 1992, trains from the 444.500 subseries began to be called 448.
As a result of the entry into service of the Euromed, Alaris and Talgo 7 branches, from 1999 on, the trains from this series of long to mid-distance products were progressively transferred, focussing their activities in the area of Catalonia.
In May 2007, the 448 series had 27 units specialised in Mid-Distance traffic, with the remaining four trains running Long Distance services.
From a technical point of view, there are no differences between the 448 and the original 444,500, meaning that the modernisation that began in 2001 to finally adapt it to Mid-Distance traffic consisted of a new interior design, with new seats and upholstery, floors and wall panelling, in addition to the incorporation of spaces for people with reduced mobility, bikers and improvements in toilets.
Body
The bodies of the 448 are made of welded steel and are self-supporting. The end carriages are made of polyester, with the driver's cab behind them. The front window of the end carriage is anti-shock and anti-fog. Two access doors from the outside, on each side, give entrance to small platforms that communicate with the passenger lounge. These doors have an automatic sliding inner footboard, although they can also be activated manually in the event of an anomaly. The interior communicating doors between lounges are automatic.
Automatic Scharfenberg couplers are used for coupling. On the cab side, coupling is mechanical, electric and pneumatic, while coupling between carriages is semi-permanent and mechanical.
The minimum composition is two carriages (Ec - Tc), although its usual composition is three: an engine carriage (Ec), an intermediate trailer (IT) and a trailer with cab (Tc) Up to nine carriages can be driven in multiple composition, controlled from a single driving position. The traction equipment, air compressor, battery and converter for auxiliary services are located under the chassis.
Traction and auxiliary systems
Four DV, MB-3165-C, mass-rolled electric motors provide propulsion (two traction motors for each engine bogie), with 4 main poles, switching poles, cylindrical laminated steel and self-ventilated steel chassis.
The engines have a power of 290 kW each, creating a combined power of 1,160 kW. The transmission has gears, flexible coupling and single gearbox, WN type.
Traction is controlled by means of cam contactors that short-circuit the start or brake resistors by weakening the field. Automatic start-up takes place by controlling the intensity of the engines. Power is generated for auxiliaries using a 150 kVA and 120 kW converter.
The pneumatic equipment is Knorr, producing air using a W230/180 compressor with a production of 1,600 l/m, driven by an 18 kW electric motor.
The battery is nickel-cadmium, and provides electricity at 72 V DC. It has 55 elements and 190 amps/hour capacity. Traction motors and converter are protected against overvoltage and overcurrent using differential sensing. Likewise, the main resistors are protected from overheating and lack of air flow for ventilation.
It incorporates equipment that facilitates the renewal of air, cooling or heating, according to the needs. Air is diffused from the ceiling, while heating comes from the floor. Finally, it has Asfa and train-ground safety equipment.
Bogies, brakes and suspension
Each carriage is supported by two bogies, with the chassis and the bolster beam made of welded steel. Each engine bogie has two fully suspended traction motors, with elastic and gearbox couplings.
The primary suspension is made with coil springs and guide dampers, while the secondary suspension is made with two pneumatic springs and a horizontal hydraulic damper.
It is equipped with a pneumatic brake (compressed air), combined with the rheostatic brake, and electromagnetic brake with railskid.
It has two disc brakes on each axle, mounted on the wheels of the engine bogies, while in the trailer bogies are located on the axle body. All axles incorporate anti-lock system.
Dimensions and Weights