This invention provides a vacuum composite LNG cryogenic pipeline, comprising four functional
layers from the inside out: an inner composite pipeline layer, a vacuum layer, an outer composite pipeline layer, and an outer sheath layer. The inner composite pipeline layer consists of an inner spiral wire layer, a sealing layer, a braided layer, another sealing layer, and an outer spiral wire layer, arranged sequentially from the inside out. The vacuum layer is formed by an annular area between the inner and outer composite pipeline
layers, supported by an insulating
gasket ring, providing vacuum insulation. The outer composite pipeline layer consists of inner and outer spiral wire
layers as its innermost and outermost layers, a sealing layer as its second layer, and a braided layer as its third layer. The outer sheath layer comprises an outer sheath. This invention offers superior bending flexibility and low
bending stiffness, making it less prone to
fatigue damage under external tensile and bending cyclic loads. It also provides excellent insulation, more rational stress transmission in cryogenic pipelines, and a wider range of applications.