The utility model discloses an automatic ultrasonic wave axletree defectoscope spout the fat subassembly, its include the butter machine and with butter machine intercommunication spout the fat pipe, it is effective in carrying butter machine spun coupling fat back axle to spout fat. Should spout the fat subassembly and spray coupling fat on can the back axle, and avoid detecting a flaw at the axletree and examine the time measuring manual work and paint coupling fat, and can use manpower sparingly, and can improve the detection efficiency that detects a flaw of axletree. The utility model discloses still disclose the probe carrier mechanism of the ultrasonic wave axletree defectoscope of automizing, it has been used the aforesaid and has spouted the fat subassembly, in use manpower sparingly, to improve detection efficiency favourable. The utility model also discloses an use the automatic ultrasonic wave axletree defectoscope of above -mentioned probe carrier mechanism, has province's manpower, efficient characteristics.