The tapered bit is an important part of the drilling rig, and it is used frequently, so the drilling rig is also a part that often fails when it is working. Once a failure occurs, the drilling rig cannot work, which will bring various losses to the project.

　　If it is a drilling rig with high-speed earth throwing function, the sequence valve controlling the throwing of the earth is stuck or damaged, resulting in poor oil return from the oil circuit that opens the friction plate, and the friction plate is in a semi-engaged state, which will also cause abnormal rotation of the power head. In this case, it is enough to clean the sequence valve or replace the sequence valve. The sequence valve can also be removed to cancel the high-speed soil-throwing function to ensure normal construction.

　　Blockage of the oil circuit will also cause a similar failure phenomenon, and the solution is to dredge the pipeline. The slewing bearing of the follower frame is damaged, replace the slewing bearing. The main valve relief pressure is too low. There is generally a main safety valve and a separate relief valve for each valve section on the main valve. The pressure relief of the main safety valve and the relief valve controlling each valve section of the power head will cause the tapered bit to rotate weakly. If the main safety valve overflows, not only will the rotation be weak, but walking, main hoisting, auxiliary hoisting, and slewing will all be in a state of weakness. Re-adjust the relief pressure of the main safety valve or the relief valve of the power head valve plate, and this fault can be eliminated.

　　The general problem is here. If you encounter this situation again in the future, you can solve it by yourself or maintain the tapered bit and drill pipe regularly, so that this kind of failure can be avoided.