Special screwed joint connecting structure for titanium alloy oil well tube

The invention provides a special screwed joint connecting structure for a titanium alloy oil well tube. The male sealing face of the structure is of an arc face type, the female sealing face of the structure is of a taper face type, sealing is achieved through interference fit of the male sealing face and the female sealing face, and the magnitude of interference between the arc face and the taper face is determined by the chord height (shown in the description) of a profile map formed after interference of the arc face and the taper face, so that the problem that API threads and conventional threads are not suitable for titanium alloy materials is solved. The structure has the advantages that the joint connecting structure meets the requirement of international standard API 5B for oil well tubes that thread gluing of oil well tubes does not occur after multiple times of screw-on or screw-off operation; thread gluing of a sleeve does not occur after two times of screw-on or screw-off operation, and thread gluing of an oil tube does not occur after nine times of screw-on or screw-off operation. Due to the fact that titanium alloy is low in surface hardness and poor in wear resistance, risks can be avoided by means of the arc face-taper face sealing mode; according to the arc face-taper face sealing mode, sealing face contact pressure is distributed evenly in a hill shape.