DF1井氮气泡沫欠平衡钻井实践与认识

Practice and Experience on Under-balanced Drilling with Nitrogen-foam

摘要:

氮气加泡沫欠平衡钻井是当前国际上已经成熟的一种钻井新技术。其优点是静液柱压力低，漏失量小，携屑能力强，对油气层损害小，保证水敏性地层钻井安全；可及时发现油气层，提高单井产量；因而能够最大限度地发现和保护中、低压低渗油气藏，以获取比常规过压钻井高得多的经济效益。在大牛地气田DF1井的施工应用中，针对本工区低压、低渗、水敏的特点，使用该项技术，很好地解决了工区内使用普通泥浆造成对产层污染的问题，并取得了成功。

Abstract:

Under-balanced drilling with nitrogen-foam is an international mature technology with advantages of low pressure of hydrostatic, less leakage, strong cutting carrying capacity, less damage to oil-gas layer and safe drilling in water-sensitive layer. With this technology, low pressure and low permeability oil-gas reservoir can be discovered and protected furthest for much higher economic benefit than conventional over-pressure well. It was applied in DF1 Well of Danudi gas field of low pressure and water-sensitive layer, and pollution on producing formation by ordinary slurry was solved.