8. If the drilling rig has been idle for a long time or after the hydraulic system is repaired, the casing of the power head rotation, traveling oil motor and main oil pump should be filled with hydraulic oil before starting.
8. If the drilling rig is idle for a long time or after the maintenance of the hydraulic system, the hydraulic oil should be filled into the shell of the power head rotation and travel oil motor and main oil pump before starting up.