Liquid motor
It is composed of a rotor and a stator. The rotor is a machined X-head screw with anti-corrosion and wear-resistant coating on the surface. The stator is composed of an alloy steel tube and an inner spiral rubber bushing with an X+1 head that is glued on its inner wall. The shape and size of the rotor and stator should be able to ensure the meshing relationship, and these meshing points lift in the axial direction to form a sealed cavity of the motor. When a drilling wave with a certain energy passes through, the cavity moves along the axial direction, continuously generating and disappearing, thereby pushing the rotor to eccentrically roll along the spiral inner wall of the stator, acting as a motor.
The screw motor is the main component of the drilling tool. Many practical and theoretical analysis results show that if the motor is to work normally and effectively, the pressure drop that each stage of the motor can withstand should not exceed 0.8MPa, otherwise the motor will leak. The speed drops quickly, and in severe cases, it stops rotating completely and the motor is damaged. The mud flow rate used on site should be within the recommended range, otherwise it will affect the efficiency of the motor and even increase wear.
The performance parameters of the screw motor are the main performance parameters of the screw drilling tool. The theoretical output torque of the motor is proportional to the motor pressure drop; the output revolution is proportional to the input mud flow. With the increase of load, the revolution of the drilling tool decreases very little, so As long as you control the readings of the pressure gauge on the ground and the flow of the pump, you can control the torque and speed of the downhole drilling tool.