| 摘要 |
<p>The present invention relates to a set of two coaxial pipes of PiP type, comprising at least two individual coaxial pipe elements (5a, 5b) each comprising an internal pipe (5a2,5b2) and an external pipe (5a1,5b1) with an annular space (5a3,5b3), preferably filled with an insulating material, assembled end to end by welding, comprising a sleeve (1) with a hollow tubular wall made of rigid or semirigid material, preferably a plastic or composite, surrounding the said pipe facing the region of the welded connection (7) of the two said individual coaxial pipe elements (5a, 5b), said hollow tubular wall of the sleeve comprising an outer jacket (1a) and an inner jacket (1b) which are connected in a sealed manner at their longitudinal ends (1c), thus defining an internal volume filled with a near-incompressible thermal insulator.</p> |
