连续管水平段套管内冲砂试验与效果评价

Sand Washing Test and Evaluation in Horizontal Cased Hole Using Coiled Tubing

为优化连续管水平段套管内冲砂的主要参数和验证不同工况下水平段冲砂效果,采用连续管作业机控制连续管带冲砂工具在水平段透明套管内进行冲砂试验。试验结果表明:150~180 L/min的排量虽能使清水将砂子完全带出透明套管,但必须依靠液体携砂和冲砂器上行的共同作用才能快速完成;最佳冲砂效果对应的参数为排量180 L/min,连续管内流速3.78 m/s,环空流速0.266 m/s,固定式、旋流式冲砂器的射流速度分别为34.12和23.90 m/s,下放、上提冲砂速度分别为0.3和0.6 m/min,冲砂时间9 min;在相同排量下,固定式冲砂器下放冲砂循环压力最高8.5 MPa,上提冲砂循环压力最高14.0 MPa,而旋流式冲砂器冲砂期间的循环压力均低于7.2 MPa,说明旋转式冲砂器喷嘴数量和喷射方向的多元化,使得喷嘴扫射透明套管内壁的面积更大,悬砂段砂粒紊动能力和上提通扫能力更强。研究结果可为后期水平井精细化冲砂作业参数优化提供依据,也可为降低现场施工风险提供参考。

To optimize the main parameters of sand washing in the horizontal cased hole using coiled tubing and verify the sand washing performance under different working conditions,the coiled tubing unit is used to convey the sand washing tool to carry out sand washing test in the horizontal transparent casing.The test results show that although the displacement of 150~180 L/min can make the sand completely out of the transparent casing,it must rely on the combined action of liquid-carrying and sand washing tool running out to quickly complete sand washing.The displacement for the best sand washing performance is 180 L/min,and the corresponding flow rate in coiled tubing is of 3.78 m/s and annular flow velocity is of 0.266 m/s.The jet velocities of the fixed-type and swirl-type sand washing tools are 34.12 and 23.90 m/s,respectively.The tool’s running in and out speeds are 0.3 and 0.6 m/min,respectively.The sand washing time is 9 min.Given the same displacement,the maximum circulation pressure of the fixed-type sand washing tool during running in hole is up to 8.5 MPa and is 14.0 MPa for running out of hole.While the circulation pressure during the sand washing with the swirl-type sand washing tool is lower than 7.2 MPa,which indicates that the diversified number of nozzles and the jet direction makes the washing area larger,and results in a better stirring effect of the sand in the sand suspending section and stronger washing capacity.The study can provide a reference for the operation parameters optimization of sand washing in the horizontal wells and reducing the risk of on-site operation.