Steel tubing segment, in addition to a lateral gallery with embodiment for a directional - free bore for carrying out of drilling rods

摘要

The steel tubing segment elements, which surround the transverse impact opening, have cassettes on. At the points at which, by means of the steel tubing segment through bores and / or lances are to be guided to the outside, the cassettes are inversely, and preferably also made larger. The usually on the outside of the tubbings existing external sheet metal plate is missing at these inverse cassettes and is instead to the inner side of the lateral stiffening wall members spaced apart far inwardly offset by. In this sheet metal, there is a closable opening, for example, with a metal cover sheet. The inverse cassettes are internally with respect to the conventional cassettes additionally stiffened, so that the total rigidity of the tubing segment is maintained in spite of the inverse cassettes. Preferably, this is accomplished by a filling of the outwardly open hollow space of the inverse cassettes with concrete.