A method of laying district heating pipe lengths in the ground and a pipe element for use herewith

摘要

In subterranean district heating pipe systems the problem occurs that the end portions of long, straight pipe stretches (2) expand and contract by temperature changes of the conductor pipe (16) of the heat insulated pipe, this giving rise to corresponding lateral displacements of the end portions of the transverse pipe elements (5, 6) as joined with the ends of the long pipe stretches (2). Such dis­placements are in no way desirable, and they can be counter­acted by expensive ground anchorings. According to the in­vention they are not eliminated, but reduced to an accept­able level in a simple and cheap manner, viz. by using for the said end portions such pipe elements (3), the outer sur­face of which is provided with a coarse pattern of marked depressions (10, 20), which serve to increase the friction between the pipe and the surrounding infill material (18) when the latter is of a high internal shear strength. Hereby the said displacements are reduced considerably.