There are three main types of Gantry Milling Machine in the industry which includes Conventional Gantry Type Milling Machine, Moving Gantry Machining Center and Fixed Gantry Machining Center. 

The Conventional Gantry Type Milling Machines are typically used for large-scale machining tasks that require heavy cutting, such as the production of large components for industries like aerospace, automotive, and shipbuilding. They are manually operated and have the advantage of versatility and the ability to handle oversized work-pieces that may not fit on smaller milling machines. Their operation requires skilled and experienced operators due to the manual control of the machine's movements.

The Conventional Gantry Type Milling Machine, often referred to as a Gantry Mill, is a large and powerful milling machinery used for precision machining of heavy and oversized work-pieces. It is characterized by its unique gantry-style structure. This kind of milling machine is typically operated manually, don’t have CNC Control System, with the operator manual controlling the machining process.