Schwartz砾石尺寸设计方法的解析、改进及其应用

Analysis,Improvement and Application of Schwartz Gravel Size Model

砾石尺寸的大小会影响防砂效果和油气井生产动态,砾石尺寸设计是砾石充填类防砂完井设计的关键步骤之一。Schwartz方法是国外应用广泛的一种砾石尺寸设计方法,但由于其原始文献描述模糊、设计过程电算化困难且部分参数的取值范围不明确等原因,该方法在国内应用较少。根据原始文献重新推导了Schwartz砾石尺寸设计方法,对其设计方法和过程进行了解析和改进,提出了相关参数的推荐取值,给出了简明的设计步骤,并编制了计算程序。Schwartz方法使用地层砂筛析曲线,信息依据丰富,尤其适用于不均匀地层砂及油气井产量较高的情况。

Gravel size affects directly the sand control effect and the well production performance. Therefore, gravel size design is the key step of gravel-packing sand control optimization. Schwartz model, a widely used gravel size model abroad, was rarely used in China due to unclear description in original reference, the difficult of its calculation and the uncertainty in how to determine the range of parameters. In this paper, Schwartz gravel size model is re-developed and analyzed. The design and procedure were analyzed and improved; the range of corresponding parameters was recommended; the design procedure was provided, and the program was developed. Using the sieved curve of formation sand, Schwartz model is feasible for non-uniform sand or high production rate wells especially.