基于Taguchi方法的计数式全通径压裂滑套优化设计

针对全通径压裂滑套中内滑套的动作压力不能满足现场施工要求的问题，对内滑套的结构参数进行了优化，以期在保证内滑套结构强度的同时提高内滑套的动作压力。利用Plackett-Burman设计法筛选了影响内滑套动作压力的显著影响因子，采用Taguchi方法优化了显著影响因子，通过方差分析确定了最优参数组合。采用数值模拟及室内模拟试验方法评价了内滑套优化前后的性能，得到了最优参数组合:筋宽角18.0°，筋长170.0 mm，筋厚5.5 mm，筋锥角89.5°，爪倾角115.0°，爪锥角65.0°。数值模拟得出，内滑套动作压力由4.8 MPa增大到了7.5 MPa，内滑套在运动过程中所受的最大应力由992.0 MPa增大到了1 101.0 MPa，但仍小于材料的许用应力；室内试验得出，内滑套动作压力由5.1 MPa提高到了7.9 MPa，满足现场施工要求。研究结果表明，应用Taguchi方法优化的计数式全通径压裂滑套结构参数合理。 

Design Optimization of Full Bore Stimulation Sleeves with Ball Drop Counting using the Taguchi Method

:In this paper,the structural parameters of sliding sleeves were optimized to ensure initiating pressure of internal sliding sleeve satisfy the requirements of field operations. In addition to strength enhancement of inner sliding sleeves,initiating pressures can be effectively increased in the proposed optimized design.Major factors that may affect the initiating pressure of internal sliding sleeve were identified by using the Plackett-Burman design method,then major influence factors were optimized based on the Taguchi method.The optimal combination of parameters was determined through variance analysis.Performance of the internal sliding sleeve before and after optimization were investigated through numerical simulation and experimental tests.The optimized parameters included angle of bracket width,18°;bracket length,170 mm;bracket thickness,5.5 mm;cone angle of bracket,89.5°,dip angle of jaw,115°and the cone angle of jaw,65°.The numerical simulation results showed that the initiating pressure of the internal sliding sleeve is enhanced from 4.8 MPa to 7.5 MPa.At the same time,the maximum stress of moving the internal sliding sleeve is increased from 992 MPa to 1 101 MPa,which is still below the allowable stress of the sleeve material.Experiment tests showed that the initiating pressures of an internal sliding sleeve is enhanced from 5.1 MPa to 7.9 MPa to meet field operation requirements.The results showed that the Taguchi method could be used as a reliable method in structural optimization of full bore stimulation sleeve of ball drop counting type.