METHOD OF CONNECTING OF PIPES SUPPLIED WITH INTERNAL SHELL Russian patent published in 2017 - IPC F16L13/02 

FIELD: construction.

SUBSTANCE: method of connecting of pipes provided with an inner shell with a welded outer sleeve includes placing the thermal insulation material, the inner shells joining, the ends of which protrude beyond the pipe ends for a length sufficient to seal the inner shells at the pipe ends by the length of the active heat-affected welding zone between the inner surface of the pipe and the inner shell, followed by their sealing connection by welding, placing the sleeve above the junction of the pipes, and then attaching its ends to the pipes by welding. The internal space between the pipe ends, the glass and the inner shell is filled with a material having adhesion to both the material of the tube and the sleeve, and to the material of the inner shell. The material for filling the space between the ends is made of a thermoplastic material in the form of a branch pipe of a length less than the total length of the joined projecting ends of the inner shell by the amount necessary to compress these ends during welding. The branch pipe is placed over the protruding ends of the inner shells before welding the ends of the inner shells, which is produced by heating the ends of the inner shells and the branch pipe with simultaneous longitudinal compression of the pipes before the interaction of their ends with the ends of the branch pipe.

EFFECT: invention provides sufficient reliability and durability of the connection of the inner shell by increasing the area of the welded joint both over the inner shell and at the ends of the pipe, which protects the pipes from the inner shell flaking in the joint areas and leads to a significant increase in the overhaul period.

2 dwg