Abstract: A method for carrying out grouting between adjacent gateroads in internal-staggered split-level coal mining. A return air gateroad of a stoping face and an inlet air gateroad of a heading face are not on the same level. The return air gateroad of the stoping face is arranged along a roof of a coal seam. The inlet air gateroad of the heading face is arranged along a floor of the coal seam. There is a height difference between the return air gateroad and the inlet air gateroad in a vertical direction. During the construction process, the inlet air gateroad is excavated at a delay distance of 180-200 meters from the return air gateroad. The drilling and grouting are performed while excavating the roadway, where grouting holes are arranged in a single row. A device for implementing the method is also provided.

Abstract: A perforating device includes a release sub, a rotating segment, a first centralizer, a braking segment, a casing collar locator, a traction mechanism, a second centralizer, a flex joint, a power supply segment, a shock absorber, a perforator, and a tail segment, which are in threaded connection sequentially to each other. The first joint assembly includes a first joint, a guide key, a connecting sleeve including a locking groove, a second joint, and an outer pipe; the first joint of the first joint assembly is in threaded connection to the cable bridle, and the second joint is in threaded connection to the outer pipe. The connecting sleeve is disposed inside the outer pipe and is connected to the first joint through the guide key. The second joint assembly includes a plurality of locking claws, a third joint, and a head.

Abstract: A perforating device includes a release sub, a rotating segment, a first centralizer, a braking segment, a casing collar locator, a traction mechanism, a second centralizer, a flex joint, a power supply segment, a shock absorber, a perforator, and a tail segment, which are in threaded connection sequentially to each other. The first joint assembly includes a first joint, a guide key, a connecting sleeve including a locking groove, a second joint, and an outer pipe; the first joint of the first joint assembly is in threaded connection to the cable bridle, and the second joint is in threaded connection to the outer pipe. The connecting sleeve is disposed inside the outer pipe and is connected to the first joint through the guide key. The second joint assembly includes a plurality of locking claws, a third joint, and a head.