Symmetrical differential magnetic focusing probe for detecting without detaching coating layer pipeline and implementation method

The invention discloses a symmetric differential magnetic focusing probe for detecting a pipeline without detaching a coating layer and an implementation method. The symmetric differential magnetic focusing probe comprises a support frame, the support frame is provided with an upper differential magnetic sensor assembly, a first silicon steel sheet assembly, a first excitation coil assembly, a zero magnetic flux point sensor assembly, a second excitation coil assembly, a second silicon steel sheet assembly and a lower differential magnetic sensor assembly from top to bottom; the lowest end of the support frame is provided with a sliding part; the first and second excitation coil assemblies adjust the positions of the upper and lower excitation coils through a lifting mechanism and a fine adjustment mechanism to determine a zero magnetic flux surface and a zero magnetic flux point; the zero magnetic flux point sensor assembly is arranged on a zero magnetic flux point; the upper and lower differential magnetic