Research status and prospects of novel lightweight aluminum alloy drill pipe

Abstract:

With increasing demand for deep drilling， existing steel drill pipes， titanium alloy drill pipes， and carbon fiber drill pipes cannot fully satisfy the demands for lightweight， high-temperature resistance， low cost， and high reliability. Aluminum alloy drill pipes have shown great potential due to their advantages such as low density， high specific strength， and relatively low cost. This paper systematically elaborates on failure mechanisms of aluminum alloy drill pipes under high-temperature， high-pressure， and complex load environments in deep wells， including the evolution of material microstructure， thermal stress mismatch of the connection structure， and the wear-corrosion synergistic effect on the surface. The research progress of key technologies is summarized： in terms of materials， high-temperature performance and strength are improved through the addition of rare earth elements， particle reinforcement， and optimization of strengthening phases； in terms of structure， cold assembly， double-taper thread design， and other methods are adopted to reduce stress concentration； in terms of surface strengthening， micro-arc oxidation （MAO） is taken as the core， combined with laser cladding and composite treatment technologies to enhance wear and corrosion resistance. Furthermore， bottlenecks such as high-temperature strength degradation and insufficient connection reliability are analyzed， and future research directions including the development of new materials， intelligent management， and biomimetic smart coatings are outlined. This study aims to provide a theoretical basis and technical guidance for the engineering application and future development of aluminum alloy drill pipes in ultra-deep drilling.