1. Hydraulic oil sediment: During the 2000-hour use of hydraulic oil in rotary drilling rigs, the oil also entrains a small amount of fine air bubbles during flow, which leads to oxidation of the oil. After oxidation, the acidic substances produced will change the color of the oil, either red or black, increasing its corrosiveness to metals. The sludge sediment produced after corrosion will clog the hydraulic oil filter element, hydraulic oil radiator, and the gaps of various small oil circuit valves on the distributor.

　　2. Impact of acidic substances on the rotary drilling rig system: Due to the inherent factors of temperature difference between morning and evening and regional climate, the hot air in the hydraulic oil tank cools and becomes water droplets, so the hydraulic oil inevitably contacts moisture. Moisture, air, and acidic substances produced after oxidation will cause rust and corrosion to metals, affecting the normal operation of the hydraulic system.

　　3. Air bubbles in hydraulic oil: In the hydraulic oil tank, air bubbles mixed into the oil circulate with the oil, which reduces the system pressure, worsens lubrication conditions, and also produces abnormal noise, blackens the hydraulic piston rod, slows down the machine speed, and makes movements incoherent, commonly known as "mechanical cerebral thrombosis".

　　4. Hydraulic oil heating also affects the working speed of rotary drilling rigs: While sediment clogs the hydraulic oil radiator, the hydraulic oil temperature will rise, reaching over 70 degrees. At high temperatures, the hydraulic oil loses its anti-wear lubrication function. If the hydraulic oil remains at high temperature for a long time, it will increase mechanical wear and vibration. In addition, air bubbles also increase the contact area between oil and air, accelerating oil oxidation. Since the hydraulic oil radiator is located outside the engine water tank radiator, under the action of the engine fan drawing air, the hydraulic oil radiator at high temperature will also increase the temperature of the antifreeze inside, causing the engine cooling to be abnormal and also high temperature, thereby greatly reducing the vehicle speed. At high temperatures, hydraulic oil can also cause oil pipeline rupture, oil seal rupture, blackening of the piston rod, etc., causing serious economic losses to the owner.