Device for lowering sleeve in drilled hole during gas extraction

The utility model provides a device for lowering a sleeve in a drilled hole during gas extraction. The device comprises a sleeve clamping device and a chuck pushing device. A first upper clamping seat of the sleeve clamping device is buckled on a first lower clamping seat to form a first bayonet for clamping the sleeve. A first movable clamp is arranged on the first upper clamping seat in a sliding mode. A first adjusting rod is arranged on the first upper clamping seat in a penetrating mode and connected with the first movable clamp, and clamps or releases the sleeve in the first bayonet by adjusting the first movable clamp. A second upper clamping seat of the chuck pushing device is buckled on a second lower clamping seat to form a second bayonet for clamping the sleeve. A second movable clamp is arranged on the second upper clamping seat in a sliding mode. A second adjusting rod is arranged on the second upper clamping seat in a penetrating mode and connected with the second movable clamp, and clamps or releases the sleeve in the second bayonet by adjusting the second movable clamp. The sleeve clamping device and the chuck pushing device are matched with each other for clamping or releasing the sleeve, and therefore the sleeve with the diameter of 4 inches and larger can be lowered into the drilled hole safely and efficiently, and sleeve lowering stability and safety are improved.