Width detection device for high pressure injection column e.g. for cement foundations, using flat material measuring band projecting through opening in wall of boring rod

摘要

The width detection device has an extendible and retractable measuring element in the form of a flat material measuring band (10), attached to a rotating rod positioned within a boring rod (2), via a coaxial cylinder (15) at the front end of the rotating rod, around which the measuring band is wound. The measuring band extends through an opening (22) in the wall (20) of the boring rod in the direction of the boundary region (B) of the high pressure injection column (1).