Inverted cleaning device for main bolt hole of pump shell of shielding main pump

The utility model relates to the technical field of nuclear power station shielding main pump maintenance, in particular to a shielding main pump shell main bolt hole inverted cleaning device which comprises a cleaning mechanism used for cleaning a first main bolt hole, a lifting mechanism used for placing the cleaning mechanism and a fixing mechanism detachably installed in a second main bolt hole. The lifting mechanism is in threaded lifting connection with the retention mechanism; the retention mechanism comprises a rotation stopping piece used for stopping the cleaning mechanism from rotating in the horizontal direction relative to the retention mechanism. Compared with the prior art that lifting is carried out through a worm and gear transmission assembly and a chain wheel lifting assembly, lifting is carried out through a threaded connection structure, the structure is simpler and more stable, damage is not likely to happen, and cost is lower. The cleaning device further comprises a rotation preventing