Drilling apparatus for producing a cased bore and method for operating a drilling apparatus

A method for operating a drilling apparatus, in which a cased bore is produced with a support tube, the drilling apparatus comprising:

• a first drill drive for driving a drill rod in a rotating manner, at the lower end of which a drilling tool for removing ground material is arranged,
• a mast, along which the first drill drive is movable with a sledge, and
• a second drive, with which the support tube for the cased bore can be introduced into the ground,
• wherein
• the drilling tool is configured to be moved in and out of an inner hollow space of the support tube,
• a computer unit is provided, in which a current drilling depth of the drilling tool and a depth of introduction of the support tube are indicated, and
• a monitor is provided, on which the current drilling depth in relation to the depth of introduction of the support tube can be displayed by the computer unit, which provides a gauge as to whether drilling is being carried out with the drilling tool in a preceding position or in a lagging position with respect to the support tube, wherein the method comprises:
• indicating the depth of introduction of the support tube into the ground in the computer unit,
• detecting the current drilling depth of the drilling tool during the production of the cased bore and indicating the current drilling depth in the computer unit and
• displaying by means of the computer unit the current drilling depth in relation to the depth of introduction of the support tube on the monitor.