**Abstract**

A theoretical study was conducted to investigate the limit depth reached by aluminum alloy drill pipes combined with steel pipes for deep well drilling in the Algerian country. Therefore, the present study is based on various parameters that have an impact on the fatigue behavior of these tubes, focusing particularly on the damage caused by the gravity of the dogleg in the crooked path in addition to their mechanical behavior, and determines the extent to which the aluminum drill pipe can drill without failures using well-engineering software modeling which provides the expected loads in the drilling and provides results more or less close to reality. This analysis indicates that the aluminum drill pipe has good fatigue resistance, despite the cumulative presence of axial and bending stress concentrations in the dogleg zones.

**Keywords:** tortuous trajectory, torque, drag, dogleg, 2024 aluminum alloy, fatigue
