COMPOSITE-MATERIAL PIPE AND METHOD FOR ITS FABRICATION Russian patent published in 2008 - IPC F16L9/12 F16L9/133 

FIELD: mechanics.

SUBSTANCE: pipe incorporates load-bearing composite-material carcass and tip with circular stepwise flanges representing cylindrical ledges with radial circular grooves. The first layer of the aforesaid load-bearing carcass features the thickness equal to that of the first flange, while every following layer is a combined one with alternating lengthwise or a spiral and circular layers wherein the end of every lengthwise or spiral layer is laid into the radial groove and is secured by an additional circular layer with the thickness equal to the groove depth. The propose method of pipe production consisting in a layer-by-layer laying on to the mandrel of the reinforcing layers, wherein every lengthwise or spiral combined layer is laid so that the fibers extend the reinforcing carcass edges and are secured in the tip outer edges, comprises coiling an additional circular along with deforming the previous layer and cutting off excess fibers coiling the final layer with subsequent thermal treatment and withdrawal from the mandrel. The proposed invention allows obtaining rectilinear fibers and their minimum possible deformation in all bearing layers, layer-by-layer coupling and independent layer securing on the tips.

EFFECT: smaller pipe sizes, reduced wall thickness and higher strength and reliability.

7 cl, 12 dwg