Low-temperature-resistant two-component solvent-free epoxy coating for pipeline joint coating

Abstract

The invention discloses a low-temperature-resistant two-component solvent-free epoxy coating for pipeline joint coating. The low-temperature-resistant two-component solvent-free epoxy coating for pipeline joint coating is composed of a component A and a component B; wherein the component A comprises, by weight, 30 to 45% of bisphenol F epoxy resin; 5-10% of bisphenol A epoxy resin; 5 to 10% of epoxy butyronitrile prepolymer; 3-7% of a glycidyl ether reactive diluent, 15-25% of modified silica powder, 8-15% of titanium dioxide, 3-10% of aluminum dihydrogen tripolyphosphate, 4-10% of mica powder, 0.6-1.4% of a thixotropic agent, 0.2-0.5% of a dispersing agent, 0.2-0.5% of a leveling agent, 0.3-0.7% of an antifoaming agent and 0.1-0.7% of carbon black; the component B is prepared from 50 to 75% of Mannich base and 25 to 50% of a thiourea-polyamine condensate. Compared with a common epoxy coating, the low-temperature-resistant two-component solvent-free epoxy coating for pipeline joint coating has the characteristics of being high in low-temperature curing speed, free of crystallization and precipitation, excellent in low-temperature bending resistance, excellent in low-temperature impact resistance, excellent in hot water soaking resistance, excellent in cold and hot impact resistance and the like.

Description

technical field [0001] The invention relates to a low-temperature-resistant two-component solvent-free epoxy anticorrosion coating for jointing of oil and gas pipelines, belonging to the technical field of oil and gas pipeline anticorrosion. Background technique [0002] At present, most of the main anti-corrosion layers of domestic oil and gas pipelines use 3PE anti-corrosion layers, while most of the joint anti-corrosion materials still use radiation cross-linked polyethylene heat shrinkable tape. Since the insulation resistance of radiation cross-linked polyethylene is very large, it will shield the cathodic protection current, resulting in the failure of the cathodic protection current. Two-component solvent-free epoxy coating, as a new type of sealing material, has the advantages of simple coating process, easy repair, reliable inspection results, no cathodic protection current shielding, etc., and has developed rapidly in the field of domestic pipeline joint anticorros...

AI Technical Summary

Problems solved by technology

[0004] With the promotion and use of two-component solvent-free epoxy coatings in the field of oil and gas pipeline joints, the existing two-component solvent-free epoxy coatings on the market have the following defects: ①The commonly used two-component solvent-free epoxy coatings for pipeline joints When the temperature is lower than 0 ℃, the curing speed of oxygen coating is very slow or even not curing, which is not conducive to the winter construction of pipeline joint anticorrosion in northern my country; , in the northern region of my country (the temperature can reach minus 30°C in winter), low-temperature cracking is prone to occur, resulting in anti-corrosion failure; ③The conventional two-component solvent-free epoxy coating has poor low-temperature bending resistance. In the northern region, during winter construction, When the pipe is welded and anti-corrosion, when it goes down the ditch, when the pipe is slightly bent, cracks are prone to occur at the joint part of the epoxy coating, which directly leads to the failure of the joint anti-corrosion

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