Detailed introduction

18

2023

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01

Alloy screw motor is what?


alloy screw motor is what?

  

合金螺杆


Non-professionals may rarely hear about alloy screw motors, but they are a key component that plays a vital role in the oil drilling industry. Co., Ltd. has rich experience and advanced mature technology in the production of alloy screw motors. Today, the editor will take you to understand what an alloy screw motor is, its structural characteristics and working principle.

  alloy screwThe motor is a volumetric motor. The high-pressure drilling fluid passes through a plurality of sealed cavities formed by the rotor and the stator, which have a spiral surface to rotate the rotor and drive the drill bit to break the rock. The alloy screw motor has hard characteristics such as low speed, large torque, strong overload capacity, convenient operation, simple structure, small size, large torque and power, and lateral vibration.

The alloy screw motor is mainly composed of 4 parts, including bypass valve, motor, universal joint shaft and transmission shaft.

1. Bypass valve assembly.

The bypass valve assembly is composed of valve core, valve sleeve, spring, valve port and other components. The spool valve has two positions: an open position and a closed position. The opening and closing of the bypass valve is controlled by the flow rate of the drilling fluid. In view of the harsh environment of oil drilling, these key components should generally be made of hard alloy materials with wear resistance and corrosion resistance.

During normal drilling, the pressure of the drilling fluid forces the spool to move downward, causing the spring to compress and close the passage on the valve body. At this time, the mud flows through the motor and converts the pressure energy into mechanical energy.

During the tripping operation, the mud pump stops pumping or the flow rate is small, the drilling fluid pressure disappears, the compression spring lifts the spool, and the bypass valve is opened to connect the inner hole of the drill string with the annulus. During tripping, the mud in the drill string flows into the annulus through the valve port and does not overflow onto the drilling platform. During run-in, the mud in the annulus enters the drill string through the valve port to reduce the pressure difference between the inside and outside of the drill string.

2. Motor components.

  alloy screwThe motor of the motor consists of a stator and a rotor. The stator is a rubber bushing that presses on the inner wall of the steel pipe and is firmly bonded together. The rubber inner hole is a spiral hole with multiple round ends in cross section. The rotor is a machined screw with a high hardness surface treatment. The upper end is a free end, and the lower end is connected to the universal joint shaft.

The rotor and the stator have a special meshing relationship. These joints form a helical sealing line in the axial direction, forming a sealed cavity. When a pressurized fluid with a certain amount of energy enters these sealed chambers and flows from one end of the motor to the other, it drives the rotor to rotate in the stator and converts hydraulic energy into mechanical energy.

The speed of the rotor is proportional to the input flow of the motor. By controlling the input flow, the output speed of the alloy screw motor can be controlled. 3. Cardan shaft assembly.

The cardan shaft assembly consists of a housing and a cardan shaft. The upper end of the universal joint shaft is connected to the rotor of the motor, and the lower end is connected to the water guide cover of the transmission shaft. The function of the universal joint shaft is to connect the rotor that performs planetary motion with the transmission shaft that rotates the fixed shaft, and transmit the output torque of the motor to the drill bit through the transmission shaft. Cardan shaft has petal type cardan shaft, flexible shaft and other structural forms. The flexible shaft has a certain degree of flexibility, and the upper and lower ends are threaded connections

The cardan shaft assembly consists of a housing and a cardan shaft. The upper end of the universal joint shaft is connected to the rotor of the motor, and the lower end is connected to the water guide cover of the transmission shaft. The function of the universal joint shaft is to connect the rotor that performs planetary motion with the transmission shaft that rotates the fixed shaft, and transmit the output torque of the motor to the drill bit through the transmission shaft. Cardan shaft has petal type cardan shaft, flexible shaft and other structural forms. The flexible shaft is an optical shaft with a certain degree of flexibility, and its upper and lower ends are connected with threads. The universal joint shaft housing of the straight alloy screw motor has no structural bending angle, while the steering knuckle shaft housing of the curved screw motor has a structural bending angle.