MULTI-LAYER INSULATION COATING Russian patent published in 2021 - IPC F16L58/04 B32B27/32 B32B27/06 

FIELD: pipeline construction.

SUBSTANCE: invention relates to an anticorrosive insulating coating of cold application on steel pipelines during construction and repair in field conditions. The coating contains a sequentially arranged outer impact-resistant layer, an inner additional layer applied to the outer impact-resistant layer, a first inner adhesive layer applied to an additional layer of the outer impact-resistant layer, an inner impact-resistant layer, an adhesive layer additionally applied to the surface of the inner impact-resistant layer, a second adhesive layer applied to another surface of the inner impact-resistant layer, and a primer layer. At the same time, the outer shock-resistant layer contains high-pressure polyethylene, low-pressure polyethylene modified by accelerated electron irradiation to gel fraction content of 40-75%, a heat stabilizer and carbon black. The inner additional layer applied to the outer impact-resistant layer contains high-pressure polyethylene, low-pressure polyethylene, butyl rubber and carbon black. The first inner adhesive layer applied to an additional layer of the outer impact-resistant layer contains butyl rubber, high-pressure polyethylene, petroleum polymer resin, insulating bitumen, rubber bitumen, zinc oxide, carbon black, talc. The inner impact-resistant layer contains high-pressure polyethylene, low-pressure polyethylene, butyl rubber, carbon black. The adhesive layer, additionally applied to the surface of the inner impact-resistant layer, contains high-pressure polyethylene, butyl rubber, carbon black. The second adhesive layer applied to another surface of the inner impact-resistant layer contains butyl rubber, high-pressure polyethylene, petroleum polymer resin, insulating bitumen, rubber bitumen, talc, zinc oxide, carbon black. The primer layer of the insulation coating containing butyl rubber, petroleum polymer resin, insulating bitumen, rubber bitumen, talc, zinc oxide, carbon black, additionally contains an epoxy-urethane oligomer, a copolymer of ethylene and butyl acrylate and a low molecular weight copolymer of ethylene with vinyl acetate. The compositions of the layers are given.

EFFECT: invention makes it possible to create a multi-layer cold-applied insulation coating for anticorrosive insulation of steel pipelines in track conditions, which is 1.5 times more resistant to cathodic peeling.

1 cl, 2 tbl