Sleeper Car

Overview

The Sleeper Car is a railway passenger carriage built for overnight travel, where the interior is divided into private sleeping rooms rather than open seating. A welded Underframe carries an insulated Carbody Shell shell that encloses a row of ten Sleeping Compartment served by a side Corridor and Vestibules. The car runs on two Passenger Bogie bogies, connects to the rest of the train through Coupler and Drawgear drawgear, and stops under a pneumatic Air Brake System. Onboard comfort is provided by a roof HVAC Unit unit, a Electrical System system, and a Water System feeding washbasins and toilets. A typical car weighs around 48 tonnes empty and runs at speeds up to 200 km/h on main lines.

Underframe and carbody

The structural base is the Underframe, a welded steel chassis with a Center Sill box beam running end to end as the main draft member. Two Side Sill members run along the edges, Headstock cross beams close each end and carry the coupler pockets, and six Cross Bearer beams support the floor while tying the side sills together. At each bogie position a Body Bolster transfers the carbody weight to the bogie center pivot, with the whole frame bolted by a Fastener Set. Above the underframe, the Carbody Shell is a stressed-skin shell: two Side Wall Frame side walls of vertical posts, an arched Roof Structure, a Floor Pan, and several Sheet Metal Panel stressed-skin sheets that carry load with the framing. Twelve Window Unit double-glazed windows and a continuous Body Insulation blanket of mineral wool and foam keep noise and heat out.

Sleeping compartments

The defining feature is the row of Sleeping Compartment, each a private room for one or two passengers. Two Berth Frame bunk frames fold down from the wall on gas struts, each fitted with a Berth Mattress and a safety net for the upper berth. A laminate Compartment Partition separates adjacent rooms, and a sliding Compartment Door with a latch and lock seals the room from the corridor. Each compartment includes a fold-out Fold-Out Washbasin with running water, a Storage Rack for luggage, and two Reading Light lamps with local switches. By day the berths fold away to leave seating, and by night the attendant makes them up for sleeping, which is why the room layout and the berth hardware are designed for repeated daily conversion.

Corridor and access

Passengers reach their rooms through the Corridor and Vestibules, a side aisle that runs the length of the car between the compartments and the body side. A non-slip Corridor Floor covering and several Corridor Handrail grab rails make the aisle safe to walk while the train is moving. At each end a powered Vestibule Door separates the vestibule, and a Gangway Bellows rubber bellows bridges to the next car so passengers can pass between carriages. A Folding Step deploys at low platforms to bridge the gap during boarding.

Bogies and running gear

Each Passenger Bogie is a two-axle passenger bogie tuned for ride comfort rather than tonnage. A welded Bogie Frame carries two Wheelset wheelsets, each built from a forged Axle pressed with two monobloc Rail Wheel wheels turning on Ball Bearing journal bearings. Suspension works in two stages: Coil Spring primary springs in the Axle Box axle boxes, and Air Spring secondary air springs between the bogie and the carbody that also level the floor as load changes. Four Hydraulic Damper hydraulic dampers control bounce and yaw to keep the ride quiet enough for sleeping. The forged Axle is made from EA1N steel and the monobloc Rail Wheel from ER7 steel, both heat treated for fatigue resistance under continuous high-speed running. The wheel tread carries a worn profile that interacts with the rail head to centre the wheelset and damp hunting, while the flange provides the last line of guidance through curves and switches.

Brakes, climate, and power

Braking uses the Air Brake System system. A Distributor Valve watches the brake pipe and, on a pressure drop, ports air from the Air Reservoir tanks into four Brake Cylinder cylinders that clamp the Brake Disc axle discs, with a Pressure Sensor and an O-Ring Set completing the pneumatics. Climate comes from the roof HVAC Unit unit: an AC Compressor, Condenser Coil, and Evaporator Coil cooling loop plus a Heating Element bank feed conditioned air through the Supply Ductwork under a HVAC Controller that holds each room to its own setpoint. The Electrical System system draws from the train line through a Power Supply converter, backed by a Backup Battery bank, and distributes through a Distribution Box and a Wire Bundle to the Cabin Lighting and Power Sockets outlets.

Water and sanitation

The Water System makes the car self-contained between depot stops. A Fresh Water Tank holds about 1000 liters of potable water, a Water Pump pressurizes the supply, and a Water Heater warms water for the washbasins. Two Vacuum Toilet vacuum toilets route waste through the Water Piping to a sealed Waste Tank that is emptied during servicing rather than discharged on the line, which is required on modern stock to meet environmental rules. Together these subsystems let a sleeper car operate through the night without resupply, carrying its passengers, their comfort systems, and their water and waste as one rolling unit.