1. Drilling fluid requirements: Reaming Bit can work effectively for various muds, including oil-based mud, emulsified mud and clay mud, and even clean water. The mud viscosity and specific gravity have little effect on the drilling tool, but it has a direct impact on the pressure of the entire system. If the pressure under the recommended displacement is greater than the rated pump pressure, the mud displacement must be reduced, or it is necessary to reduce the flow through the drilling tool and The pressure drop of the drill bit. Impurities such as sand particles in the mud will affect the performance of the drilling tool and accelerate the wear of the bearing and motor stator. Therefore, the sand content in the mud must be controlled below 1%. Each type of drilling tool has its own input flow range, and only within this range can the drilling tool have higher efficiency. Generally, the middle value of the input flow range should be taken as the better input flow value.

       2. Mud pressure requirements: When the drilling tool is suspended and the displacement remains unchanged, the mud pressure drop through the drilling tool will also remain unchanged. As the drill bit touches the bottom hole and the WOB increases, the mud circulation pressure increases, and the pump pressure also increases. Drilling can be controlled by the following formula: Drilling pump pressure = circulating pump pressure + drilling tool load pressure drop. The circulating pump pressure is the pump pressure when the drilling tool does not touch the bottom of the well. It is also called the off-bottom pump pressure. The pressure is about to rise, and the reading of the pressure gauge is called the drill pump pressure. The off-bottom pump pressure is not a constant, it varies with the well depth and the characteristics of the mud, but in actual operation, it is not necessary to measure the accuracy of the circulating pump pressure at any time. Generally, the off-bottom pump pressure after each connection is taken as Approximate value, this can fully meet the accuracy requirements of the formula. When the drilling tool is working, when the drilling pump pressure reaches a higher recommended pressure, the drilling tool produces better torque. Continue to increase the drilling pressure will increase the pump pressure. When the greater design pressure is exceeded, the motor may brake. At this time, it should be immediately Lower the drilling pressure to prevent internal damage to the Extension Drilling Tools.