Fatigue test device for composite material pipe

The invention provides a fatigue test device for a composite material pipe. The fatigue test device comprises a power mechanism, two joint inner cores, two joint outer sleeves and two connecting flanges, the power mechanism comprises a power source and an output shaft used for outputting torque. One end of each joint inner core is connected with a power mechanism; and the other end of the joint inner core is inserted into a sample pipe of the composite material pipe. Each joint outer sleeve is coaxially arranged outside the joint inner core in a sleeving manner, and the joint outer sleeves are used for fixing the end parts of the sample tubes between the joint outer sleeves and the joint inner core after being inwards buckled and pressed in the radius direction of the joint outer sleeves. Each connecting flange comprises a plurality of first threaded holes formed in the inner ring and a plurality of second threaded holes formed in the outer ring, the first threaded holes are used for being fixedly connected w