A standardized steel box (typically 20, 40, 45, 48, or 53 feet in length) that can be transferred between ships, trains, and trucks without unloading the contents. Containers conform to ISO or domestic standards and are the fundamental unit of intermodal logistics. Their standardization revolutionized global freight economics.
A wheeled undercarriage or trailer frame designed to carry an intermodal container over the road. Chassis are lifted onto or off of the container and are a critical piece of drayage equipment. Detention charges apply when chassis are held beyond the allowed free time at a shipper's facility.
An intermodal service in which ISO or domestic containers are loaded onto well cars or flatcars, often double-stacked, for the rail portion of a move. COFC is the dominant form of intermodal rail service in North America and enables double-stack efficiency. Containers are transferred between trucks and trains at intermodal terminals.
An intermodal service in which an over-the-road highway trailer is loaded directly onto a flatcar for the rail portion of a move, sometimes called piggyback. TOFC allows door-to-door service with standard trailers and is used where containers are not available or practical. It has largely been supplanted by COFC double-stack service on high-density lanes.
An intermodal flatcar with a depressed center section (the well) that allows stacking two 20- or 40-foot containers vertically, known as double-stack operation. Double-stacking roughly doubles the payload per train and reduces cost per container. Well cars are typically articulated in sets of five or more to reduce weight and the number of inter-car connections.
A facility equipped with cranes, reach stackers, or other lifting equipment to transfer intermodal containers and trailers between railcars and trucks. Intermodal terminals are the interface between the rail and trucking networks and are located in major metropolitan areas and port cities. Throughput capacity and truck gate efficiency are critical performance metrics.