Hole sealing device used for low-permeability coal-bed gas-phase crushing drilling hole

The utility model discloses a hole sealing device used for a low-permeability coal-bed gas-phase crushing drilling hole. The hole sealing device comprises two sets of metal members, a hole sealing apparatus, a crushing wire and a water channel. The water channel is arranged in an end face, facing drilling holes, of the hole sealing apparatus. The hole sealing apparatus can expand and contract. The hole sealing apparatus has a hollow steel pipe inside. The rubber cylinder is arranged on the outermost part of the hole sealing apparatus. A groove type sealing system is used for sealing two ends of the hole sealing apparatus. The metal members are respectively symmetrically arranged on two ends of the hole sealing apparatus. Each of the metal members comprises a male metal member and a female metal member and controls expansion and contraction of the hole sealing apparatus through water input or water releasing of the water channel. In addition, by adding the metal members on two ends of the hole sealing apparatus, the crushing wire will not be directly exposed out of the hole sealing apparatus. During crushing, the crushing wire is free from shock of high-pressure gas, so using frequency of the crushing wire is greatly increased.