钻井周期预测新方法的建立

文章综合分析了国内外钻井周期预测方法，归纳出历史水平法、典型案例法、学习曲线法、工序工时法、周期定额法等，并进行了简要分析和论述。采用两个油气田的实际数据进行分析，建立了一种平均先进钻井周期预测新方法。充分考虑了钻井工程施工的阶段性、程序性和不确定性的特点，提出了按井眼尺寸和套管尺寸系列进行分段的方法。在系统分析周期定额编制方法、学习曲线法等多种方法的基础上，按照定额编制平均先进性的原则要求，建立了“0.3、0.5、0.2”分段加权平均先进法编制钻井周期定额的数学模型，编制出两个油气田钻井周期定额。研究给出了钻井周期预测数学模型，已应用于10余口井钻井周期预测和设计，取得了良好效果。

ESTABLISHING A NEW METHOD FORECASTING DRILLING CYCLE

This paper analyses and discusses five means of forecasting petroleum drilling cycle in the world, including historical level method, typical cases method, learning curve method, procedure work-hour method and cyclic rating method. Based on a lot of correlative data of two oilfields, in this paper a new average advancement technique for forecasting petroleum drilling cycle is introduced. Taking into full consideration the different phases existed in the drilling, the procedural requirements and the uncertainty of the drilling engineering, a method for segmentation by well sizes and casing sizes is set up. On the basis of systematic analysis of these methods, including cyclic ratings preparation method and learning curve method, according to the requirements of average advancement of the rating method, a mathematical model for cyclic rating decision is established which applies weighting factors of 0.3, 0.2 and 0.5 to different segments. 2 cyclic ratings for oil/gas field drilling are made. The drilling cycle prediction model set up during the study has been applied to predict and design the drilling cycles on over 10 wells, with good results.