wherein the plug part comprises a plug housing, a pin provided in the plug housing, and a push-pull sleeve, a rotary sleeve, a front retaining ring, a ratchet lock nut and a rear retaining ring provided outside the plug housing; one end of the plug housing is provided with a submarine cable A; the plug housing is uniformly provided with slider mounting holes for mounting sliders along a radial direction, and the sliders are radially movable along the slider mounting holes; an inner wall of the plug housing is provided with an unequal-width key group for guiding the socket part, and the keys of the unequal-width key group are provided between the sliders; the plug housing is provided with a hoop mounting structure A, and both sides of the hoop mounting structure A are provided with force-bearing bosses A; the plug housing is also provided with a housing pin hole A and a thread A for connecting external equipment; the plug housing is provided with a sealing ring groove A for sealing between the external equipment and the plug housing, wherein the push-pull sleeve is configured to press the sliders and the rotary sleeve; an end of the push-pull sleeve is provided with a stop block mounting hole for mounting a stop block, wherein the stop block is configured to clamp the ratchet lock nut to prevent a threaded connection between the ratchet lock nut and the plug housing from being loosened, and the other end of the stop block is provided with a spring for ejecting the stop block to lock the ratchet lock nut; the push-pull sleeve is provided with a push-pull sleeve pin mounting hole for mounting a threaded pin, and the threaded pin is used for preventing the stop block from sliding out and rotating; the rotary sleeve is provided with a slider pin groove, and the slider is provided with a slider pin, and the slider pin groove is matched with the slider pin to implement a radial movement of the sliders by rotating the rotary sleeve and thereby implement the locking and unlocking of the plug part and the socket part; the plug housing is further provided with a rear retaining ring groove for mounting the rear retaining ring, wherein the rear retaining ring is configured to prevent the ratchet lock nut from slipping out; the plug housing is further provided with a front retaining ring groove for installing the front retaining ring, and the front retaining ring is configured to prevent the rotary sleeve from slipping out;

the socket part comprises a socket housing and a jack provided in the socket housing; the pin and the jack are matched to connect the plug part and the socket part; one end of the socket housing is provided with a submarine cable B which is provided coaxially with the submarine cable A; the socket housing is provided with a hoop mounting structure B, both sides of which are provided with force-bearing bosses B; the socket housing is provided with a slider groove matched with the slider and a bell mouth guide keyway group matched with the unequal-width key group, wherein an insertion end of the bell mouth guide keyway group is trumpet-shaped and thereby convenient for the unequal-width key group to be smoothly inserted within a certain angle range so as to insert the pin into the jack; the socket housing is also provided with a sand-proof sealing ring groove for mounting a sealing ring to prevent sand; the socket housing is further provided with a housing pin hole B and a thread C for connecting the external equipment; the socket housing is provided with a sealing ring groove B, and a sealing ring is provided at the sealing ring groove B to seal between the external equipment and the socket housing.