Design Optimization and Performance Analysis of the Pneumatic DTH Hammer with Self-Propelled Round Bit

Although pneumatic down-the-hole (DTH) hammers have good performance of high penetration rate and minimal deviation tendency in the vertical section oil gas wells, they not been successfully used directional drilling due to drill tool wear wellbore disturbance. Herein, we developed a novel type DTH hammer with self-propelled round bit overcome technical difficulties drilling. Nonlinear dynamic modeling by authors was analyze working principle hammer. The kinematics dynamics simulation this were carried out using MATLAB language, motion law piston revealed. numerically simulated evaluated considering fluctuations front rear chamber pressure, impact energy, acceleration, frequency. results show that our hammer’s is feasible has an adequate structural design. demonstrate reasonable design parameters. Compared numerical for conventional hammers, velocity acceleration changed smoothly. frequency slightly higher than while other parameters nearly equal. can be drilling, trenchless seabed sampling