大规模水力压裂过程中超级13Cr 油管冲蚀预测模型建立

Erosion prediction model for super 13Cr tubing during large-scale hydraulic fracturing

王治国 杨向同 窦益华 罗生俊

WANG Zhiguo YANG Xiangtong DOU Yihua LUO Shengjun

西安石油大学机械工程学院 中国石油塔里木油田分公司 中国石油西部钻探工程有限公司试油公司

School of Mechanical Engineering, Xi’an Shiyou University, Xi’an, Shaanxi 710065, China PetroChina Tarim Oilfield Company, Korla, Xinjiang 841000, China Well Testing Company, Xibu Drilling Engineering Inc. CNPC, Karamay, Xinjiang. 834000, China

大规模水力压裂过程中，高速流动的携砂压裂液会对油管内壁造成冲蚀，导致油管壁厚减薄，承载能力降低。为了准确预测大规模水力压裂过程中油管的冲蚀速率，利用自制的冲蚀实验装置，采用0.2 % 胍胶压裂液与40/70 目石英砂混合形成的液固两相流体，实验研究了冲蚀角度和流体流速对超级13Cr 油管冲蚀速率的影响，建立了适用于大排量高砂比压裂的冲蚀预测模型，运用新模型，可以比较准确地预测注入总液量和排量对超级13Cr 油管壁厚损失的影响。算例分析结果表明，大规模压裂过程中，超级13Cr 油管的壁厚损失范围为0.2~1.3 mm，应该控制排量和砂含量，防止油管壁由于冲蚀而导致安全性降低。

Sand-carrying fracturing fluid flowing at high-speed during large-scale hydraulic fracturing can erode inner walls of tubing, resulting in thinning of tubing sidewall and reduction of tubing loading capacity. To predict erosion rate of tubing during large-scale hydraulic fracturing accurately, the impacts of erosion angle and fluid flow speed on erosion rate of the super 13Cr tubing have been tested with an erosion testing unit made by ourselves, solid-liquid dual-phase fluid made of 0.2 % guar fracturing fluid and quartz sand of 40/70 meshes, and an erosion prediction model for fracturing with large discharging rate and high sand proportion has been constructed. By using the newly constructed model, impact of total fluid volume and discharging rate on wall thickness loss of the super 13Cr tubing can be predicted accurately. Case study results show the super 13Cr tubing may lose sidewall thicknesses of 0.2-1.3 mm during large-scale fracturing. Therefore, cares shall be taken to control discharging rate and sand content properly to maintain necessary safety performance of tubing sidewalls in case of erosion.

10.13639/j.odpt.2016.04.013