What is gantry or portal crane?

portal crane, also known as gantry crane, commonly known as gantry crane or gantry crane, is a crane built on a gantry, and a gantry is a structure that can span huge objects. Gantry cranes are capable of lifting some heavier objects.
A gantry or portal crane is a type of crane consisting of a bridge or a beam supported by two legs that run on rails or wheels. This type of crane is commonly used in construction, shipyards, and other industries for lifting and moving heavy objects or materials. The bridge or beam of the crane is supported by trolleys that can move along the legs, allowing the crane to have a wide range of movement. Gantry cranes are often used in applications where overhead space is limited, as they do not require a runway or overhead support structure.