油气固井纤维水泥浆性能研究

为了提高水泥石的抗冲击能力,延长油井生产寿命,在油井水泥浆中加入了纤维。研究了纤维对水泥浆流变性、稠化时间、失水的影响,实验结果表明,纤维的加入对水泥浆的流变模式无影响,但对流变参数有一定影响,当纤维掺量为0.12%~0.19%、长度为400~1400 μm时,有利于改善水泥浆的流变性能;与不掺纤维的水泥浆相比,纤维水泥浆的稠化时间稍有减小,但不影响施工;对于水泥浆的失水性能来说,纤维长度和掺量均存在最优值,该实验条件下纤维最佳掺量为0.12%~0.37%,最佳长度为700~1400 μm。该研究证明了在水泥浆中加入适当长度及掺量的纤维可有效提高水泥石的界面胶结强度及韧性,从而为纤维水泥应用于现场提供可靠保证。

Performance of Fiber Cement Slurry for Well Cementation

To improve the anti-impacting fracture ability of set cement, and meanwhile prolong oil well production longevity, fiber cement slurry system has been formerly tested by our subject group, which has shown that the use of fiber can effectively reduce volume shrinkage of set cement, and improve the interface cementing quality and toughness of set cement. To meet the needs of cementing operations, the full-length paper has made experimental research on the performance of fiber cement slurry. Results show that the use of fiber has no effect on cement-slurry rheological mode, but has some influence on its rheological behavior. When fiber proportion ranges from 0.12% to 0.19% and fiber length from 400 μm to 1400 μm, the rheological behavior of cement slurry can be improved. Under normal pressure, the use of fiber can extend the thickening time at some extent, but has no effect on field operations. For water loss of cement slurry, there are optimal values for fiber length and proportion. The optimal range separately is 0.12%~0.37% and 700~1400 μm under this test conditions. Research results show that the employment of fiber with appropriate length and proportion in cementing slurry can benefit the cementing operations.