Patent Number: 048633119
Section: summary

BACKGROUND OF THE INVENTION The present invention is directed to a lining or covering for bore holes in salt rocks used for storing radioactive materials, the bore holes consisting of superimposed tubular sections. Radioactive waste after suitable conditioning are inserted into final storage containers and terminally stored in geological formations. The terminal storage containers are so designed that they safely surroud the radioactive inventory, block the radioactive rays, withstand the pressure of the rocks and also are effectively protected against corrosion during the longterm storage. Therefore, it has been the practice to make such terminal storage containers very expensively of steel, constructed partially in multiple layers, and provided with special corrosion protection devices. There are needed a large number of pieces of such expensive and relatively difficult to handle containers which are stored in caverns or bores without any possibility of recovery for reuse. This point is also true for containers and packages made of ceramic material which are besides, sensitive to the pressure of the rocks. There are known from German No. OS 3034821 above ground intermediate storage members for radioactive materials in containers in which the shielding containers are located in superimposed tubular sections made of concrete. Likewise there are known storage tunnels lined or covered with concrete. The present invention is based on the problem of providing a covering for bore holes in salt rocks for the storage of radioactive materials comprising superimposed tubular sections which make possible the receiving of the static shielding and corrosion protection members of terminal storage containers so that these can be laid out in their stored containers of lower weight but simply and at low cost in order to be easily and conveniently handled. SUMMARY OF THE INVENTION The objects were obtained according to the invention by making the tubular sections of a metallic material and having each of them composed of an outer ring and an inner ring which are securely joined together by an intermediate ring of a electrochemically nobler material, welding the intermediate rings of the individual tubular sections together, the inner rings being not as high as the outer and intermediate rings in order to form a recess in the interior of the covering. The outer rings have upper and lower edges and directly engage an intermediate ring, whereby in each case there is applied in one of the recesses a support ring having twice the height of the depth of the recess and made of the same material as the intermediate ring and welded to the intermediate ring. In assembly, one inserts each support ring in the free recess of each adjacent outer ring, whereby the bottom of the recess in the outer ring sets deeper than the bottom of the recess in the inner ring. It is advantageous if the inserted side of the support ring grasp the free recess of the adjacent outer ring and there are provided manipulated recesses in the inner ring. Advantageously the inner rings and the outer rings comprise spherical case graphite.