大庆油田深层气井微间隙封堵固井技术

Cementing technology of microclearance block in deep gas wells of Daqing Oilfield

为了解决深层天然气固井后气窜的问题,大庆油田开展了微间隙封堵固井技术的研究。通过对庆深气田气窜机理的研究,分析了微裂隙、微环隙形成的主要原因,计算了不同规格的套管由于憋压而引起的微环隙数值,提出了新的消除微环隙、微裂隙的防窜措施,即封堵液封堵技术。大量的室内试验和现场模拟试验表明,该封堵液悬浮性能和流变性能好,封堵和防气窜效果明显。

The cementing technology of microclearance block is studied in Daqing Oilfield in order to solve the gas migration problem of deep-zone gas after cementing. This paper analyzes the main reasons of microclearance and micro-annulus formation through the study of gas migration mechanism in the field. It calculates the microclearance, figure due to the pressure blocking of casing. The new measures are proposed to remove the microclearances and micro-annulus. This is called as block liquid technology. The laboratory experiments approve that the block liquid has a good rheological property and good levitation property. The effectiveness of blocking gas migration is very obvious.