海上“落鱼”井实施打捞与侧钻方案的经济分析

Economic analysis for offshore well fishing and sidetracking scheme

摘要:

井下“落鱼”打捞工期的不确定性导致施工成本不可控，制定合理的打捞经济决策点至关重要。本文以渤海油田某“落鱼”井为例，不打捞“落鱼”则需在“落鱼”上部进行套管开窗侧钻，为两开井身结构，打捞“落鱼”则在套管鞋下裸眼侧钻，为一开井身结构，放弃打捞或者盲目打捞都并非最经济的方案。通过对冲砂打捞工期进行量化，提出了经济工期和决策工期，通过现场尝试冲砂打捞作业，在决策工期内分析其作业难度，并判断是否能够在经济工期内完成作业，最大程度降低总体实施成本，提高油田开发经济效益。渤海油田A井应用该决策方法，共节约费用近420万元。提出的“落鱼”井打捞经济工期和决策工期计算方法具有一定的推广价值。

关键词:“落鱼”;打捞;侧钻;经济工期;决策工期

Abstract:

The uncertainty of fishing schedules makes operation costs uncontrollable, and it is of vital importance to formulate a proper economic decision point. This paper takes a certain fishing well in Bohai Oilfield as an example. Sidetracking from above the fish was necessary without fishing, or from below the casing shoe with fishing. Abandoning fishing or fishing blindly was not the most economical solution. The two concepts i. e., the economic operation period and the decision-making period, were proposed by quantifying the fishing period. Through field fishing attempts, the difficulty of the operation was analyzed during the decision-making period, and it was determined whether the operation can be completed within the economic period; thus minimizing overall operation costs and improving economic benefits of oilfield development. This decision-making method was applied at Well A in Bohai Oilfield, saving a total of nearly 4.2 million. The calculation method for the economic fishing period and the decision-making period proposed in this paper is worthy of promotion.

Key words:fish; fishing; sidetracking; economic construction period; decision-making period