Study on mechanical characteristics of anchor drilling rig group for rapid excavating

Sci Rep. 2023 Mar 20;13(1):4524. doi: 10.1038/s41598-023-31809-z.

Abstract

Aiming at the imbalance problem of excavating and anchoring efficiency ratio in the underground coal mine, a new type of parallel operation unit of excavation-supporting-anchoring is proposed to improve the excavating efficiency. Considering the uneven factors of the roof and floor of the coal mine roadway, the influence of different drilling angles and leg support angles on the leg support force is studied under the condition of simultaneous drilling of multiple drilling rigs. The results show that the maximum support force is 4.002 KN when the leg angle is different and the drilling angle is different. By constructing the coupling vibration model of the multi-drill drilling process and using the Lagrange method to solve the vibration law of key components of the anchorage system, the vibration law of drill pipe under different influencing factors such as cantilever extension, multi-drill simultaneous drilling, and drilling incident angle is studied. The results showed: (1) The vibration of the drill pipe in the cantilever extension state is more severe than that in the retracted state, and the maximum vibration peak reaches 7.61 mm. (2) The vibration response of the drill pipe is the most intense under the condition of four top anchor drilling rigs drilling at the same time. Under the working condition of only two drilling rigs, the vibration response of the drill pipe is the smallest. (3) As the drilling angle of the drilling rig increases, the vibration response of the drill pipe is more severe and the vibration amplitude is larger. A test prototype is built to simulate the actual anchoring drilling process, and the vibration law of the support platform and the drilling rig is obtained through the vibration detection system. The test results show that the vibration law of the key components is approximately the same as the theoretical simulation results. The relevant theoretical results can provide a technical basis for the drilling stability of the anchoring system.