含硫气井酸压管柱受力及敏感性因素分析

LOADS ON ACID FRAC STRING USED IN SULFUR-CONTAINING GAS WELLS AND ANALYSIS ON SENSITIVE FACTORS

超深含硫气井生产管柱一般要满足替浆、坐封、改造、求产等多种工况,不同工况下井筒内温度压力变化范围广,导致管柱受力情况复杂,易出现管柱失效;同时含硫气井投产管柱需采用合金材质,管柱设计不合理将导致建井成本大幅度增加。文章详细论述了超深含硫气藏生产管柱受力分析模型建模过程,针对特定区块储层特征,开展了井筒压力温度分布模型校正及敏感性因素分析,系统全面的介绍了管柱力学分析技术,并以塔河油田深层含硫气藏为例,分析计算了测试管柱和投产管柱受力情况,归纳总结了压裂过程管柱受力情况随施工排量的变化过程,提出了塔河油田完井测试管柱的推荐方案。

Tubing strings in ultra-deep sour gas wells have to meet requirements of various working conditions,such as slurry replacement,packer setting,fracturing,production and etc.The borehole temperature and pressure vary a lot under different operation conditions,resulted in very complex loads on string and even string failure. And the tubing string used must be alloy in sour gas wells,any improper string design will lead to sharp increase in well construction cost. The model for sour-well tubing string mechanics analysis is introduced in this paper. And taking the reservoir properties of specific blocks as an example,the correction of borehole temperature-pressure distribution model, sensitive factors analysis and string mechanics analysisprocess are described. The paper ends with a case in Tahe Oilfield,an ultra-deep reservoir. The analysis and calculation of loads on well testing strings and production strings helps us to understand how the load on fracturing string changes with the pump rate. And a completion test string is recommended for Tahe Oilfield in this paper.