PIPE WITH INTERNAL PLASTIC SHELL Russian patent published in 2016 - IPC F16L9/02 

FIELD: production of fittings.

SUBSTANCE: invention relates to pipeline transport and can be used in construction of pipelines of various purpose, transporting corrosive medium. Pipe with internal plastic shell has concentrically arranged at ends of pipes and attached to it prefabricated protective sleeves. Prefabricated protective sleeves consist of internal and external rings, outer rings are made with wall thickness not exceeding thickness of plastic shell. Internal ring is equipped with external face. On external surface, in area of plastic shell, internal ring has circular grooves with depth not less than 0.5 mm and not more than 1/3 thickness of internal ring. Annular grooves are provided on ends of chamfers or at corners with rounding. Thickness of external ring is less than thickness of shell by not more than 1/3. External and internal rings are connected to each other inside pipe by welding.

EFFECT: pipe with internal plastic shell reduces cost of anticorrosion protection of pipe, provides strength of prefabricated protective sleeves, ensures required tightness and strength of zone of pressing plastic shell to steel pipe.

1 cl, 3 dwg