... operate, 2.strong torque,high drilling efficency The most stable mobile hydrogeologic drilling rig AKL-S ... in various geological conditions construction, overall for the pulling type, mechanical drive, some hydraulic control ... rigs, hydraulic lift..(3). Has a through hole with big diameter, drilling depth, large torque, high ... *16.7Weight (t)9.4 The most stable mobile hydrogeologic drilling rig AKL-S-400 ...