Cement block incorporating a length of metal tube for use in making smoke ducts for modular buildings

摘要

The present invention concerns a cement block for use in making smoke ducts for modular buildings on the inside of which a metal tube is flexibly mounted that has a mouth at the base of increased diameter and at the top a section that projects in relation to the top of the said cement housing; it is arranged that the length of tube that projects from one such block is inserted into the enlarged lower mouth of the tube incorporated in the superimposed identical block. IMAGE