空气潜孔锤孔底局部反循环封堵工具研究与应用

空气潜孔锤钻进工艺钻进效率是常规钻井工艺的10~20倍,对提高矿产资源勘探开发效率,促进贵州省经济发展具有重大意义.西南(贵州)喀斯特地区是全球最大的喀斯特连片分布区,碳酸盐岩地层分布广泛,溶洞及溶隙、裂隙发育,在使用空气潜孔锤钻进工艺钻进时,容易发生漏风现象,导致返渣困难,甚至发生卡钻、埋钻事故.双壁钻杆空气潜孔锤局部反循环钻进工艺可以有效解决喀斯特地区空气潜孔锤钻进工艺使用困难的问题,但该工艺使用的封堵工具极易磨损,限制了该工艺在深井钻探中的使用.本项目主要以双壁钻杆空气潜孔锤局部反循环封堵工具为对象,通过调整封堵工具结构,增加封堵环旋转性能等手段,对封堵环进行改良和优化设计,增加封堵工具的使用寿命,实现双壁钻杆空气潜孔锤局部反循环钻进工艺在深井钻探中的应用.

Sealing device for partial reverse circulation drilling with the DTH air hammer

The drilling efficiency of air DTH hammer drilling technology is 10 to 20 times higher than that of conventional drilling technology,which is of great significance for improving mineral resource exploration and development efficiency,and promoting the economic development of Guizhou Province.The southwest(Guizhou)karst area is the largest karst continuous area in the world,where carbonate strata is widely distributed,and karst caves,dissolution fissures and fractures are developed.When drilling with air DTH hammer drilling technology,air leakage is prone to occur,which leads to difficulty in return of cuttings,and even bit sticking and burial accidents.Though the partial reverse circulation drilling process with dual?wall drill rods and the air DTH hammer can effectively solve the difficulty in application of the air DTH hammer drilling process in the Karst area,but the existing sealing device is prone to wear,which limits the application of the process in deep well drilling.With the sealing device for partial reverse circulation drilling with the dual?wall drill rod and the air DTH hammer as the subject of study,through adjusting the structure of the sealing device and improving the rotation performance of the sealing ring,modification and optimization is conducted of the sealing ring to extend the service life of the sealing tool so that local reverse circulation drilling with the dual?wall drill rod and the air DTH hammer can be applied in deep well drilling.