定向穿越用超大规格螺杆钻具的研制与试验

Development of Ultra-large Specification Positive Displacement Motor Used for Directional Drilling Crossing

在大口径管道施工中,采用常规定向穿越技术时钻杆承受扭矩大,导致钻杆扭断或寿命大幅缩短。为此,提出了大口径管道穿越动力前置工艺,设计研制了定向穿越用超大规格螺杆钻具。该螺杆钻具与现有施工工艺参数基本匹配,不需额外增加设备。为分析采用超大规格螺杆钻具作为孔底动力进行复合钻进时的效果,将其与常规定向穿越扩孔钻进进行对比。试验结果表明:使用螺杆钻具作为孔底动力,可弥补因长距离穿越造成的钻机扭矩衰减,同时能够提高机械钻速,减少钻杆应力循环次数,从而延长钻杆的使用寿命,降低作业事故发生率。该产品的研制成功提高了定向穿越技术现场应用的安全性。

In the construction of large-diameter pipeline, the conventional directional drilling crossing tech-nology often observes fatigue break and greatly reduced service life of drill pipe under large torque. To address the issue, the front positioned power section has been proposed for large-diameter pipeline drilling crossing. The ultralarge specification positive displacement motor used for directional drilling crossing has been designed and developed, which basically match with the existing operation parameters without additional equipment. In order to analyze the composite drilling performance of the newly developed device as the bottomhole power, it is compared with the conventional directional drilling crossing operation. The test results show that the newly developed device can make up for rig torque reduction caused by long distance crossing, improve the drilling rate, reduce the number of drill pipe stress cycle, thus, extending the service life of the drill pipe and reducing the incidence of operation accidents.