Ultrasonic testing special probe for butt girth welding of austenitic stainless steel pipe

The invention discloses an ultrasonic testing special probe for butt girth welding of an austenitic stainless steel pipe. The probe adopts a send-receive double crystal focusing structure, so that geometrical scattering of the inner wall of a steel pipe is reduced, and random and interfering echo caused by a wedge block is reduced; an inward concave curved surface is arranged at the bottom of a delay tapered wedge, so that the top of the inward concave curved surface is in contact with the steel pipe to be tested; a horizontal polarized shear wave is generated in the austenitic stainless steel pipe by the special probe and cannot be converted into other types of waves when compared with other wave forms and reflected from the surface parallel to the polarization direction; random echo is less; the horizontal polarized shear wave is almost entirely transmitted into the weld metal, and the acoustic beam directional deflection is minimum when compared with other wave forms. The ultrasonic testing special probe c