Anti corrosion engineering of new materials coating for marine facilities
The marine atmospheric corrosion environment of coastal steel structures such as offshore wind power, ports and wharves is full of salt fog.
The marine atmospheric corrosion environment of coastal steel structures such as offshore wind power, ports and wharves is full of salt fog. The salt mist contains chloride salts, such as sodium chloride and magnesium chloride, which can absorb moisture at very low relative humidity, and chloride ions are also highly corrosive. Therefore, salt spray has a strong corrosion effect on metal structures and their protective layers in coastal or offshore areas. Academician Hou Baorong and others have shown in long-term experimental results that the spray splash area is a neglected "tiger". Compared with the coating of steel structures in the atmospheric area, the cathodic protection of underwater parts, and the spray splash area of offshore steel structures in the areas with the most serious marine corrosion, it is a real corrosion protection weakness.
The following measures are mainly taken at home and abroad for the corrosion of the spray splash area of offshore steel structures:(1) Increase the corrosion allowance (causing steel waste, increasing the cost, and there is still potential safety hazard because uneven corrosion cannot be avoided); (2) Coating protection (corrosion in splash zone can not be solved), (3) coating seawater resistant alloy (expensive, difficult to promote and apply comprehensively);
The new material coating anti-corrosion scheme for offshore facilities is a multi-layer structural composite material composed of "high-strength material+new material layer+protective layer+solid oil layer", which has durable corrosion resistance, aging resistance, puncture resistance, scratch resistance and impact resistance. It is a new coating anti-corrosion protection technology developed for the corrosion characteristics and protection requirements of steel structures in the splash zone.
This technology not only integrates the characteristics of several currently popular coating anti-corrosion systems, but also avoids the shortcomings of various coating technologies. Compared with conventional anti-corrosion protection technologies, the new material coating anti-corrosion scheme for offshore facilities has obvious technical advantages: ① low requirements for surface treatment. Below St2, there may be a small amount of water, oil stain, floating rust, etc. on the surface; ② Strong structural adaptability. The coating can be completed on any complex structure surface, and can resist crack shrinkage and expansion changes within a certain range without damage; ③ Impact resistance and puncture resistance. High strength ultra fiber protective layer and high memory fiber layer can resist impact, stab and scratch, and ensure that the armor is firmly covered; ④ Simple construction and short construction period.
Application scope of new material coating anti-corrosion scheme for offshore facilities splash zone corrosion