井筒温度和压力场计算是深水海底泵举升钻井设计的重要内容.综合考虑温压场与泥浆性能,特别是泥浆流变性能的相互影响,建立深水海底泵举升钻井井筒传热和流动耦合计算模型,并与常规隔水管钻井计算结果进行比对.结果表明:受海水低温影响,上部井段环空温度小于入口温度,海底泵举升钻井井筒温度小于常规隔水管钻井,需注意低温时天然气水合物形成带来的安全隐患;海水段和地层段压力存在不同的压力梯度,地面泵压小于循环压耗,海底泵举升钻井井筒压力小于常规隔水管钻井;考虑泥浆密度和泥浆流变性能变化对井筒温度、ECD 和泵压均有影响,相对来说,ECD 受前者影响较大,而井筒温度场和泵压受后者影响较大;两者都考虑,泵压计算误差将大大降低.
The calculation of wellbore temperature and pressure is an important part in deepwater subsea mud lift drilling (SMD) design. Considering the influence of temperature, pressure and mud property, this study established a model of flow and heat transfer in the borehole of SMD. The results show that affected by the low seawater temperature, the upper wellbore annulus temperature was lower than the mud entrance temperature; the temperature in the borehole of SMD was lower than that of regular deepwater drilling; the potential safety problems caused by gas hydrate formation need to be watched. The pressure gradients in the borehole were different between the sea section and underground section. The pump pressure above the ground was lower than the circulating pressure loss, and the pressure in the borehole of SMD was lower than that in regular drilling. Both mud density and viscosity had impact on the equivalent circulating density (ECD) and pump pressure and temperature in the borehole, while the former had relatively large impact on ECD, and the latter had relatively large impact on the pump pressure and temperature. When both were considered, the calculation error of pump pressure would be greatly reduced.
[1] Stiles D, Trigg M. Mathematical temperature simulators for drilling deepwater HTHP wells: Comparisons, applications and limitations[C]. SPE/IADC Drilling Conference, Amsterdam, The Netherlands, February 20-22, 2007.
[2] 高永海, 孙宝江, 王志远, 等. 深水钻探井筒温度场的计算与分析[J]. 中国石油大学学报: 自然科学版, 2008, 32(2): 58-62． Gao Yonghai, Sun Baojiang, Wang Zhiyuan, et al. Calculation and analysis of wellbore temperature field in deepwater drilling[J]. Journal of China University of Petroleum: Natural Science Edition, 2008, 32(2): 58-62.
[3] 宋洵成, 管志川. 深水钻井井筒全瞬态传热特征[J]. 石油学报, 2011, 32(4): 704-708． Song Xuncheng Guan Zhichuan. Full transient analysis of heat transfer during drilling fluid circulation in deep- water wells[J]. Acta Petrolei Sinica, 2011, 32(4): 704-708.
[4] 夏环宇, 翟应虎, 安岩, 等. 深水钻井隔水管增压排量对井筒温度分布 的影响[J]. 石油钻探技术, 2012, 40(1): 32-35． Xia Huanyu, Zhai Yinghu, An Yan, et al. The effect of boost flow in riser on the wellbore temperature in deep water drilling[J]. Petroleum Drilling Techniques, 2012, 40(1): 32-35.
[5] Harris O O, Osisanya S O. Evaluation of equivalent circulating density of drilling fluids under high-pressure/high-temperature conditions[C]. SPE Annual Technical Conference, Dallas, Texas, USA, October 9-12, 2005.
[6] 汪海阁, 刘岩生. 高温高压井中温度和压力对钻井液密度的影响[J]. 钻采工艺, 2000, 23(1): 56-60． Wang Haige, Liu Yansheng. Effect of temperature and pressure on drilling fluid density in HTHP wells[J]. Drilling & Production Technology, 2000, 23(1): 56-60.
[7] 管志川. 温度和压力对深水钻井油基钻井液液柱压力的影响[J]. 石油 大学学报: 自然科学版, 2003, 27(4): 48-52． Guan Zhichuan. Effect of temperature and pressure on fluid column pressure of wellbore drilling fluid in deep-water drilling with oil-based drilling fluid[J]. Journal of the University of Petroleum: Natural Science Edition, 2003, 27(4): 48-52.
[8] 王博. 深水钻井环境下的井筒温度压力计算方法研究[D]. 东营: 中国 石油大学, 2007． Wang Bo. Research on the method of wellbore temperature and pressure calculation during deep-water drilling[D]. Dongying: University of Petroleum, 2007
[9] 郭晓乐, 汪志明. 大位移井循环压耗精确计算方法研究及应用[J]. 石 油天然气学报, 2008, 30(5): 99-102． Guo Xiaole, Wang Zhiming. Precise method of calculating circulating pressure loss in extended reach wells[J]. Journal of Oil and Gas Technology, 2008, 30(5): 99-102.
[10] 鄢捷年, 李志勇, 张金波. 深井油基钻井液在高温高压下表观粘度和 密度的快速预测方法[J]. 石油钻探技术, 2005, 33(5): 35-39． Yan Jienian, Li Zhiyong, Zhang Jinbo. Methods for quickly predicting apparent viscosity and density of oil-based drilling fluids under HTHP conditions[J]. Petroleum Drilling Techniques, 2005, 33(5): 35-39.
