由于计划封堵和废弃的井数量众多，使用铋合金作为封堵和废弃的屏障材料在文献中得到了广泛关注。此外，人们对水泥的长期密封效率提出了许多问题。在此背景下，本文对用共晶铋锡合金制成的塞子的密封性进行了深入研究。
这项工作分为三个方面：实验室测试以验证这些塞子的耐压性和泄漏率，显微镜分析以通过观察合金微观结构来证实测试的见解，以及数值模拟以捕捉和模拟所涉及的现象，旨在重现未来真实的井场景。
结果表明，铋锡塞比水泥塞具有更好的耐压性和更低的泄漏率，这表明这种材料是一种合适的候选材料。当塞子在比大气压力更高的固化压力下设置时，密封性能会更好，观察形成的微结构可以证实这一点。
最后，提出了一种适合捕捉凝固时膨胀的材料模型，并观察了热膨胀对插头和管道组件的影响。
本摘要摘自挪威科技大学 L. Hmadeh、A. Manataki、MA Jaculli、B. Elahifar 和 S. Sangesland 撰写的论文 SPE 219744。该论文已通过同行评审，可在 OnePetro 上的 SPE 期刊上以开放获取形式获取。
The use of bismuth alloys as a barrier material for plugging and abandonment has gained traction in the literature because of the large number of wells scheduled to be plugged and abandoned. In addition, many questions have been raised regarding the sealing efficiency of cement in the long run. Within this context, this work performs a thorough study of the sealability of plugs made with the eutectic bismuth-tin alloy.
This effort is divided into three fronts: laboratory tests to verify the pressure resistance and leakage rate of these plugs, microscopy analyses to corroborate the tests’ insights through observations of the alloy microstructure, and numerical simulations to capture and model the involved phenomena aiming to reproduce real well scenarios in the future.
Results show that bismuth-tin plugs exhibit better pressure resistance and lesser leakage rates than cement plugs, which indicates that this material is a suitable candidate. Better sealing properties are achieved when the plugs are set under higher curing pressures than the atmospheric pressure, an observation that is confirmed when observing the microstructures formed.
Finally, a suitable material model that captures the expansion upon solidification is proposed, and the effect of thermal expansion on the plug and pipe assembly is observed.
his abstract is taken from paper SPE 219744 by L. Hmadeh, A. Manataki, M. A. Jaculli, B. Elahifar, and S. Sangesland, Norwegian University of Science and Technology. The paper has been peer reviewed and is available as Open Access in SPE Journal on OnePetro.