The working principle of a drilling multifunctional safety rotary plug valve

The working principle of a drilling multifunctional safety rotary plug valve includes the following aspects:

1. **Remote Control Operation**:

   - The valve is equipped with a remote-controlled motor and signal receiving control switch, allowing users to control the opening and closing of the plug valve through remote control.

2. **Support Protective Cover and Automatic Opening and Closing Mechanism**:

   - A support protective cover is installed on the outside of the opening and closing handle, which features an automatic opening and closing mechanism. This allows workers to control the opening and closing of the safety plug valve body without climbing high drilling pipes, reducing safety hazards associated with manual operations.

3. **Ball Valve Body and Movable Valve Seat**:

   - The valve body contains a fixed valve seat, below which is a movable ball valve body and a resettable movable valve seat. The movable valve seat includes a sealing part that is in sealing contact with the valve body and an enlarged chamber that accommodates the sealing part, with the cross-sectional area of the enlarged chamber being greater than that of the sealing part.

4. **Pressure Relief and Check Valve Function**:

   - In the event of a blowout or kick, the ball valve body is closed to prevent well control incidents; at the end of drilling, if the device is placed at a specified depth or cannot be opened, continuous positive pressure can break the fixed pins, allowing the ball valve body and movable valve seat to form a unidirectional check valve.

5. **Fluid Flow Control**:

   - The plug valve controls fluid flow by rotating the plug. The plug is typically cylindrical or conical, and its internal channel works in conjunction with the valve body's channel. Rotating 90 degrees achieves the opening and closing of the valve.

6. **Reduce Friction and Improve Sealing Effect**:

   - The design includes a first pressure relief pipe and a second pressure relief pipe, which can reduce the oil pressure on one side inside the plug valve body, decrease the unidirectional thrust of oil pressure on the plug valve column, reduce friction between the plug valve column and the sealing ring, ensure good contact and sealing of the sealing ring on the plug valve column, and extend the service life of the plug valve body.

7. **Structural Optimization and Easy Maintenance**:

   - The plug valve body has a thread opening at one end and a threaded pipe at the other end, facilitating the installation and removal of the plug valve body. Additionally, a sealing gasket is placed between the upper surface of the plug valve column and the end cap to ensure the sealing between the plug valve column and the end cap, making replacement and maintenance easier.

In summary, the drilling multifunctional safety rotary plug valve, through its unique design and working principles, achieves various functions such as remote control, pressure relief, check valve protection, and reduced operational risks, providing effective safety assurance for drilling operations.