高酸性气藏完井类陶瓷覆膜处理技术

Application of the quasi-ceramic coating technique to well completion in highly sour gas reservoirs

完井工具在高酸性气藏中的腐蚀破坏普遍存在。对完井工具的腐蚀形式和各种处理技术进行了研究。研究结果表明,采用化学气—固平衡反应工艺制取(TiCr)xNy和(TiCr)xNy膜具有很好的阻氢效果,其防止氢渗透的效率是抗氢不锈钢的1 000倍以上,可以有效防止氢进入材料内部所造成的氢致应力腐蚀。通过模拟井下H2S环境的室内的腐蚀试验结果表明,在各种工具表面制备的多层致密类陶瓷覆膜能够适应油田井下各种复杂的腐蚀环境,提高完井工具的防腐性能及其部分机械性能指标,从而为高酸性气藏完井研究了一种安全新型、经济合理的关键技术。

The corrosion of well-completion tools used in highly sour gas reservoirs is very common.The present paper dealt with the corrosion of well-completion tools and the related anti-corrosion techniques,and the study found that（TiCr）xNy and（TiCr）xNy membranes prepared in a chemical gas-solid equilibrium reaction process were very helpful in hydrogen resistance,their efficiency of preventing hydrogen from permeation was 1000 times higher than that of hydrogen-proof stainless steel,so they could effectively resist the hydrogen-induced stress corrosion by preventing hydrogen from entering the interior of materials.Through a laboratory corrosion experiment on material samples used for well-completion tools at a simulated downhole H2S environment,the study proved that dense quasi-ceramic multi-layer coatings prepared on the surface of various tools were capable of adapting to various complex downhole corrosive environments,enhancing corrosion-proof properties of well-completion tools and improving some of their mechanical performance indicators.Therefore,this key technique is a safe and economical new approach for the anticorrosion of well-completion tools used in highly sour gas reservoirs.