A method of manufacturing a large-diameter composite material pipe elbow

Abstract

A method for manufacturing a large-diameter composite material pipeline elbow. First, the left and right inner shells are made on the elbow half-mold, and a layer of surface felt is laid first; then, two layers of chopped strand felt are laid; Make the total thickness of the inner shell reach 6-10mm, and complete the production of the left and right halves of the inner shell after demoulding; butt the left and right two halves of the inner shell, and then lay resin-soaked plastic along the surface of the inner shell from one end face to the other Lay layers of unidirectional yarn; then alternately lay the outer shell layer in the order of two layers of square grid cloth and one layer of chopped strand mat until the designed thickness is reached, and release the mold after curing. The present invention makes full use of the advantages of the designability of the composite material, optimizes the lay-up structure, improves the ability of the elbow to withstand the tensile and compressive stress generated by the bending moment, thereby reducing the risk of leakage and rupture of the composite material elbow and reducing waste products The efficiency is improved, and the reliability of the product is improved; the weak link in the FRP pipeline is solved, and the stability of the whole pipeline is improved.

Description

technical field [0001] The invention relates to a manufacturing technology of a pipeline elbow, in particular to a manufacturing method of a large-diameter composite material pipeline elbow. Background technique [0002] For elbows with a diameter greater than 450mm, the manufacturing method is to manually paste half of the inner lining on the male mold, then demoulding and butt the two halves of the inner lining to form a whole elbow inner lining, and then alternately lay on the above inner lining Paste gingham and chopped strand mat until design thickness is achieved. Because the fibers in the square cloth have been woven, it has more bending points and cannot resist large tensile and compressive loads. For the composite material elbow manufactured by this process, when there is liquid pressure inside, the elbow will be subjected to the bending moment generated by the internal pressure, thereby generating tensile stress on the inner side of the elbow and compressive stre...

AI Technical Summary

Problems solved by technology

When the pipeline is subjected to high internal pressure or water hammer, the inner tensile stress of the elbow exceeds the range that the traditional elbow can withstand, cracks are likely to occur between the hoop fiber bundle and the lap joint of the grid cloth, and the composite structure is damaged, resulting in leakage or rupture