A fully hydraulic drilling drilling rig is a drilling rig that uses hydraulic pressure to drive and control all moving parts. This type of drilling rig realizes the stepless speed change by means of the high-pressure variable oil pump and the variable oil motor, which can simplify the transmission mechanism and remove the gear box, which not only reduces the weight of the drilling rig, but also makes full use of the power. At the same time, the drilling rig has high speed, stable operation, convenient and safe operation, easy to realize automation and instrumentation, and has good adaptability to high-speed small-diameter drilling (such as diamond drilling) and engineering drilling with high torque and low speed. However, the processing and manufacturing of the hydraulic components of this kind of drilling rig is complicated, and the requirements for use and maintenance are relatively high. According to its structure, it can be divided into two types: vertical axis full hydraulic drilling rig and power head full hydraulic drilling rig. The fully hydraulic drilling rig has been widely used in the world, and it is also the main direction of the development of new drilling rigs in China.