Image Number 4 for United States Patent #6397957.
A jacket tube for a device for drilling holes and forming an anchorage in the earth or rock. The jacket tube is coupled with a drill pipe and/or a drill bit or a drill hammer and is configured with a plurality of through openings across its periphery. Once the borehole has been made, or after an anchor has been introduced, the jacket tube can be filled with a hardenable suspension. The jacket tube consists of at least one expanded metal element which has evenly distributed through openings and connecting elements, especially sleeves, at the ends for connecting to a drill bit and/or other jacket tube elements. The borehole is therefore easy to produce and the jacket tube can be anchored securely.