Bogie in the context of Axle

A well car, also known as a double-stack car (or also intermodal car/container car), is a type of railroad car specially designed to carry intermodal containers (shipping containers) used in intermodal freight transport. The "well" is a depressed section that sits close to the rails between the wheel trucks of the car, allowing a container to be carried lower than on a traditional flatcar. This makes it possible to carry a stack of two containers per unit on railway lines (double-stack rail transport) wherever the structure gauge assures sufficient clearance.

The top container is secured to the bottom container either by a bulkhead built into the car — possible when bottom and top containers are the same dimensions, or through the use of inter-box connectors (IBC). Four IBCs are needed per well car. In the terminal there are four steps: unlock and lift off the top containers of an inbound train, remove the bottom containers, insert outbound bottom containers, lock assembly after top containers emplaced. Generally this is done car-by-car unless multiple crane apparatus are employed.

The Boeing 747 is a long-range wide-body airliner designed and manufactured by Boeing Commercial Airplanes in the United States between 1968 and 2023.After the introduction of the 707 in October 1958, Pan Am wanted a jet 2+1⁄2 times its size, to reduce its seat cost by 30%. In 1965, Joe Sutter left the 737 development program to design the 747. In April 1966, Pan Am ordered 25 Boeing 747-100 aircraft, and in late 1966, Pratt & Whitney agreed to develop the JT9D engine, a high-bypass turbofan. On September 30, 1968, the first 747 was rolled out of the custom-built Everett Plant, the world's largest building by volume. The 747's first flight took place on February 9, 1969, and the 747 was certified in December 1969. It entered service with Pan Am on January 22, 1970. The 747 was the first airplane called a "Jumbo Jet" as the first wide-body airliner.

The 747 is a four-engined jet aircraft, initially powered by Pratt & Whitney JT9D turbofan engines, then General Electric CF6 and Rolls-Royce RB211 engines for the original variants. With a ten-abreast economy seating, it typically accommodates 366 passengers in three travel classes. It has a pronounced 37.5° wing sweep, allowing a Mach 0.85 (490 kn; 900 km/h) cruise speed, and its heavy weight is supported by four main landing gear legs, each with a four-wheel bogie. The partial double-deck aircraft was designed with a raised cockpit so it could be converted to a freighter airplane by installing a front cargo door, as it was initially thought that it would eventually be superseded by supersonic transports.

Steel casting is a specialized form of casting involving various types of steel cast to either final/net or near-net shape. Steel castings are used when iron castings cannot deliver enough strength or shock resistance.

Examples of items that are steel castings include: hydroelectric turbine wheels, forging presses, gears, railroad truck frames, valve bodies, pump casings, mining machinery, marine equipment, turbocharger turbines and engine cylinder blocks.

A flatcar (US) (also flat car, or flatbed) is a piece of rolling stock that consists of an open, flat deck mounted on trucks (US) or bogies (UK) at each end. Occasionally, flat cars designed to carry extra heavy or extra large loads are mounted on a pair (or rarely, more) of bogies under each end. The deck of the car can be wood or steel, and the sides of the deck can include pockets for stakes or tie-down points to secure loads. Flatcars designed for carrying machinery have sliding chain assemblies recessed in the deck.

Flatcars are used for loads that are too large or cumbersome to load in enclosed cars such as boxcars, but which will not be harmed by the weather. They are also often used to transport intermodal containers (shipping containers) or trailers as part of intermodal freight transport shipping.

A refrigerator car (or "reefer") is a refrigerated boxcar (U.S.), a piece of railroad rolling stock designed to carry perishable freight at specific temperatures. Refrigerator cars differ from simple insulated boxcars and ventilated boxcars (commonly used for transporting fruit), neither of which are fitted with cooling apparatus. Reefers can be ice-cooled, come equipped with any one of a variety of mechanical refrigeration systems, or use carbon dioxide (as dry ice) or liquid nitrogen as a cooling agent. Milk cars (and other types of "express" reefers) may or may not include a cooling system, but are equipped with high-speed trucks and other modifications that allow them to travel with passenger trains.

A train wheel or rail wheel is a type of wheel specially designed for use on railway tracks. The wheel acts as a rolling component, typically press fitted on to an axle and mounted directly on a railway carriage or locomotive, or indirectly on a bogie (CwthE) or truck (NAmE). The powered wheels under the locomotive are called driving wheels. Wheels are initially cast or forged and then heat-treated to have a specific hardness. New wheels are machined using a lathe to a standardised shape, called a profile. All wheel profiles are regularly checked to ensure proper interaction between the wheel and the rail. Incorrectly profiled wheels and worn wheels can increase rolling resistance, reduce energy efficiency and may even cause a derailment. The International Union of Railways has defined a standard wheel diameter of 920 mm (36 in), although smaller sizes are used in some rapid transit railway systems and on ro-ro carriages.

A wheelset is a pair of railroad vehicle wheels mounted rigidly on an axle. Wheelsets are often mounted in a bogie ("truck" in North America) – a pivoted frame assembly holding at least two wheelsets – at each end of the vehicle. Most modern freight cars and passenger cars have bogies each with two wheelsets, but three wheelsets (or more) are used in bogies of freight cars that carry heavy loads, and three-wheelset bogies are under some passenger cars. Four-wheeled goods wagons that were once near-universal in Europe and Great Britain and their colonies have only two wheelsets; in recent decades such vehicles have become less common as trainloads have become heavier.

The Gauge Change Train (GCT) or Free Gauge Train (フリーゲージトレイン; "FGT") is the name given to a Japanese project started in 1994 to develop a high-speed train with variable gauge axles to allow inter-running between the 1,435 mm (4 ft 8+1⁄2 in) standard gauge Shinkansen network, and the 1,067 mm (3 ft 6 in) narrow gauge regional rail network.

Two three-car and one four-car "GCT" electric multiple unit (EMU) trains have been built for testing. The first train operated from 1998 until 2006, the second train operated from 2006 until 2014 and the third-generation train commenced testing in 2014, although testing is currently suspended due to technical issues with the bogies. The GCT was due to be introduced on the Nagasaki Shinkansen upon its opening in 2022, but JR Kyushu announced in June 2017 that it had abandoned plans to adopt the GCT for these services.

A railroad car, railcar (American and Canadian English), railway wagon, railway carriage, railway truck, railwagon, railcarriage or railtruck (British English and UIC), also called a train car, train wagon, train carriage or train truck, is a vehicle used for the carrying of cargo or passengers on a rail transport network (a railroad/railway). Such cars, when coupled together and hauled by one or more locomotives, form a train. Alternatively, some passenger cars are self-propelled in which case they may be either single railcars or make up multiple units.

The term "car" is commonly used by itself in American English when a rail context is implicit. Indian English sometimes uses "bogie" in the same manner, though the term has other meanings in other variants of English. In American English, "railcar" is a generic term for a railway vehicle; in other countries "railcar" refers specifically to a self-propelled, powered, railway vehicle.

A current collector (often called a "pickup") is a device used in trolleybuses, trams, electric locomotives and EMUs to carry electric power (current) from overhead lines, electric third rails, or ground-level power supplies to the electrical equipment of the vehicles. Those for overhead wires are roof-mounted devices, those for rails are mounted on the bogies.

Typically, electric current connectors have one or more spring-loaded arms that press a collector or contact shoe against the rail or overhead wire. As the vehicle moves, the contact shoe slides along the wire or rail to draw the electricity needed to run the vehicle's motor.

Milk cars are a specialized type of railroad car intended to transport raw milk from collection points near dairy farms to a processing creamery. Some milk cars were intended for loading with multiple cans of milk, while others were designed with a single tank for bulk loading. Milk cars were often equipped with high-speed passenger trucks, passenger-type buffer plates, and train signal and steam lines seldom found on conventional refrigerator cars.

Bombardier Transportation was a Canadian rolling stock and rail transport manufacturer, with headquarters in Toronto and Berlin. It was one of the world's largest companies in the rail vehicle and equipment manufacturing and servicing industry, prior to being acquired by Alstom in 2021. Bombardier Transportation had many regional offices, production and development facilities worldwide. It produced a wide range of products including passenger rail vehicles, locomotives, bogies, propulsion and controls. In February 2020, the company had 36,000 employees, and 63 manufacturing and engineering locations around the world. Formerly a division of Bombardier Inc., the company was acquired by French manufacturer Alstom on 29 January 2021.

The leading wheel, or leading axle or pilot wheel, of a steam locomotive is an unpowered wheel or axle located in front of the driving wheels. The axle or axles of the leading wheels are normally located on a leading truck. Leading wheels are used to help the locomotive negotiate curves and to support the front portion of the boiler.

On a steam locomotive, a trailing wheel or trailing axle is generally an unpowered wheel or axle (wheelset) located behind the driving wheels. The axle of the trailing wheels is usually located in a trailing truck. On some large locomotives, a booster engine was mounted on the trailing truck to provide extra tractive effort when starting a heavy train and at low speeds on gradients.

Trailing wheels were used in some early locomotives but fell out of favor for a timeduring the latter 19th century. As demand for more powerful locomotives increased, trailing wheels began to be used to support the crew cab and rear firebox area.

In rail transportation, a rolling highway or rolling road is a form of combined transport involving the conveying of road trucks by rail, referred to as Ro-La trains. The concept is a form of piggyback transportation.

The technical challenges to implement rolling highways vary from region to region. In North America, the loading gauge is often high enough to accommodate double stack containers, so the height of a semi-trailer on a flatcar is no issue. However, in Europe, except for purpose built lines such as the Channel Tunnel or the Gotthard Base Tunnel, the loading gauge height is much smaller, and it is necessary to transport the trailers with the tires about 30 cm (11.81 in) above the rails, so the trailers cannot be simply parked on the surface of a flat car above the wagon wheels or bogies. Making the wagon wheels smaller limits the maximum speed, so many designs allow the trailer to be transported with its wheels lower than the rail wagon wheels. An early approach in France was the Kangourou wagon with modified trailers. This technology did not survive, due to the market resistance to modified trailers. Today, three designs for these special wagons are in commercial service, "Modalohr", "CargoBeamer" and "Niederflurwagen".

A bogie or railroad truck holds the wheel sets of a rail vehicle.