A variety of equipment can be used to perform intermodal operations at a terminal. The choice of equipment is related to a number of factors in terms of capital investment, volume, stacking density, and productivity.
- The forklift (not shown) can be considered the most basic piece of intermodal equipment but has limitations and is able to handle only loaded 20-foot containers or empty containers of other dimensions. This is not a piece of equipment suitable for intermodal operations.
- The hostler truck (not shown) is designed to move containers loaded on chassis within terminals. Although it represents a low capital investment and can move containers at a high speed, it is restricted to move containers already loaded on chassis and therefore requires other equipment.
- The straddle carrier is a flexible piece of equipment that can be used for all intermodal operations such as loading/loading railcars and trucks as well as stacking containers up to three in height depending if the straddle carrier is a 3-high or 4-high. So, depending on the straddle carrier type, the stacking density may vary between 500 and 700 TEU per hectare. Straddle carriers are often used to move containers for piers to stacks.
- The front-end loader is a more restricted piece of equipment that can reach stacks of up to 3 full containers and can be used for double-stack intermodal rail operations. It can also be used to manage empty stacks by reaching up to 8 empty containers in height.
- The reach stacker (also known as a side loader) is also a flexible piece of equipment performing intermodal operations for rail and trucks as well as the stacking of containers. Since reach stackers are limited to stacks of three full containers (four or five empty) they can support a stacking density of 500 TEU per hectare. They are often used in intermodal rail terminals and in maritime terminals for specialized moves (e.g. reefers).
- The rubber-tired gantry (RTG) is a fixed intermodal piece of equipment that is used for loading and unloading railcars from trucks in high-density terminals as it can span over up to 4 rail tracks. It is also used for stacking operations where it can manage densities of up to 1,000 TEU per hectare with stacks of up to 4 full containers or 5 empty containers. It can service 8 to 9 trucks per hour, which involves 30 to 40 container movements since containers need to be reshuffled within their stacks. The RTG has higher acquisition costs, but lower operational costs, and fits well regular container yard operations.
- The rail-mounted gantry (RMG) is a fixed piece of intermodal equipment that is widespan and can be used for intermodal operations over 6 to 10 rail tracks. While they tend to be mostly used at port terminals for operations over large container stacks, new intermodal rail terminals are increasingly relying on RMGs to perform intermodal operations over a series of train tracks, often with some below crane space for track-side stacking. Several RMG models can swivel, allowing for perpendicular crane side loading and unloading. An RMG used solely for stacking can accommodate densities above 1,000 TEU per hectare (4 full or 5 empty containers).
- A portainer is a gantry crane strictly used to load and unload containerships and comes in different sizes based upon the ship class they can accommodate. While a Panamax portainer can accommodate ships up to 13 containers in width, a Post-Panamax portainer reaches up to 18 containers alongside. The latest class of portainers is dubbed “Super Post Panamax” and can handle the latest generation of containerships of 12,500 TEU by being able to span up to 22 containers. Containers have to be brought to the portainer by holsters using chassis or by straddle carriers.
The ongoing automation of intermodal terminals is replacing the manually operated conventional equipment with semi or fully automated improvements. This is particularly the case for portainers, gantries, and straddle carriers, which can be remotely controlled.