Composition and Working Principle of Rotary Control Device
When the rotary control device is in operation, the drilling tool drives the central pipe and sealing rubber core to rotate together with the drill string through the upper drive assembly of the rotary assembly. The sealing rubber core seals the annulus between the drilling tool and the wellhead casing by its own elastic deformation. When pressure exists in the annulus, the well pressure acts on the conical surface of the sealing rubber core to form pressure-assisted sealing, ensuring wellhead safety.