Application of a quick drill pipe connection method in high-power electro-hydraulic drilling rigs

In order to solve the problem of long time consumption and low efficiency in the pickup and placement and unscrewing of the drill pipe screw (drill pipe connection) on high-power electro-hydraulic drilling rigs, a quick drill pipe connection method is proposed. To achieve quick drilling and drill pipe connection, a method of closed loop linkage of the manipulator and power head synchronization on the buckle is adopted. After receiving the command for drilling and drill pipe connection, the mechanical arm, mechanical beam, and power head act simultaneously. When the drill pipe interferes (collides) with the power head and main holder during the curve trajectory movement, the mechanical beam stops acting. And the power head continues to retreat away from the main holder. When the interference is removed, after the mechanical beam continues to move until it is in place, the manipulator large arm and small arm are linked to quickly place the drill pipe into the middle loading and unloading area from top to bottom. When the forward rotation pressure reaches the preset value of 10 MPa, the screw engagement of the drill pipe ends. Aiming at the continuous cyclic action of lifting and connecting the drill pipe, the differential displacement synchronization method is adopted. By calculating the difference between the radial retraction of the mechanical grip and the axial displacement of the beam, the problems such as excessive time and interference of the manipulator in grasping and releasing the drill pipe during the loosening process of the power head and drill pipe threads are effectively solved. When the mechanical grip radially rises by 300 mm, the greater the difference in axial displacement from the mechanical beam, the safer it will be. After the power head releases the front buckle, the manipulator resets and control ends. The results of industrial tests show that compared with conventional methods, the average time saved by this quick drill pipe connection method for drilling down and drill pipe connection and lifting and drill pipe connection is 179 s and 41 s respectively, and the success rates of overall drilling down and drill pipe connection and lifting and drill pipe connection have increased by 22.3% and 19.1% respectively.