Apparatus and methods for preparing a blast hole in a rock face during a mining operation are disclosed. An exemplary method comprises: deploying a first tool toward the blast hole in the rock face via a common tool outlet of a feed unit using a first tool station of the feed unit; retracting the first tool from the common tool outlet using the first tool station of the feed unit and retaining the first tool in the first tool station; and while the first tool is retained in the first tool station, deploying a second tool toward the blast hole in the rock face through the common tool outlet of the feed unit using a second tool station of the feed unit.

Apparatus and methods for preparing a blast hole in a rock face during a mining operation are disclosed. An exemplary method comprises: deploying a first tool toward the blast hole in the rock face via a common tool outlet of a feed unit using a first tool station of the feed unit; retracting the first tool from the common tool outlet using the first tool station of the feed unit and retaining the first tool in the first tool station; and while the first tool is retained in the first tool station, deploying a second tool toward the blast hole in the rock face through the common tool outlet of the feed unit using a second tool station of the feed unit.

A microwave-mechanical fluidization mining system and a mining method for metal mines. The microwave-mechanical fluidization mining system comprises a microwave pre-splitting mechanical mining system, a microwave separation system, a high-power microwave focused melting system and a goaf, wherein ore-waste rock mixtures mined by the microwave pre-splitting mechanical mining system are transported to the microwave separation system through a conveyor and an elevator on the microwave pre-splitting mechanical mining system, separated ores are transported to the high-power microwave focused melting system, and separated waste rocks are transported through a conveyor to the goaf for filling. Microwave pre-splitting mechanical mining is adopted instead of a traditional blasting mining method to increase an excavation speed and avoid the influence of blasting on the stability of surrounding rocks.

A microwave-mechanical fluidization mining system and a mining method for metal mines. The microwave-mechanical fluidization mining system comprises a microwave pre-splitting mechanical mining system, a microwave separation system, a high-power microwave focused melting system and a goaf, wherein ore-waste rock mixtures mined by the microwave pre-splitting mechanical mining system are transported to the microwave separation system through a conveyor and an elevator on the microwave pre-splitting mechanical mining system, separated ores are transported to the high-power microwave focused melting system, and separated waste rocks are transported through a conveyor to the goaf for filling. Microwave pre-splitting mechanical mining is adopted instead of a traditional blasting mining method to increase an excavation speed and avoid the influence of blasting on the stability of surrounding rocks.

The present disclosure relates to a technical field of coal mining, particularly to a method of no-pillar mining with gob-entry retaining adapted for fully-mechanized top coal caving in a thick coal seam, which comprises the following steps: reinforcing support on a roof and two sides of a roadway; performing roof slitting blasting to form a pre-splitting slit; erecting a temporary support device and a gangue retaining device in the roadway along the retained entry; performing no caving within a range of a preset distance at an end of the working face near the retained entry side; and removing the temporary support device in the roadway after entry forming stabilizes, and closing the goaf to complete entry retaining. The roof slitting blasting is more beneficial to collapse of strata in the goaf, so that the strata in the slit can better fill stoping space after collapse, and the roof of the retained entry forms a short arm beam structure laterally, which avoids forming a long suspended roof in the goaf, and improves the stress of surrounding rock of gob-side entry retaining; coal caving is not performed in a certain range at the end of the working face of the retained entry side, which further ensures the filling effect of the goaf on the retained entry side, effectively limits the rotary sinking of blocks of the main roof, and greatly reduces effect on the stability of the retained entry.

The present disclosure relates to a technical field of coal mining, particularly to a method of no-pillar mining with gob-entry retaining adapted for fully-mechanized top coal caving in a thick coal seam, which comprises the following steps: reinforcing support on a roof and two sides of a roadway; performing roof slitting blasting to form a pre-splitting slit; erecting a temporary support device and a gangue retaining device in the roadway along the retained entry; performing no caving within a range of a preset distance at an end of the working face near the retained entry side; and removing the temporary support device in the roadway after entry forming stabilizes, and closing the goaf to complete entry retaining. The roof slitting blasting is more beneficial to collapse of strata in the goaf, so that the strata in the slit can better fill stoping space after collapse, and the roof of the retained entry forms a short arm beam structure laterally, which avoids forming a long suspended roof in the goaf, and improves the stress of surrounding rock of gob-side entry retaining; coal caving is not performed in a certain range at the end of the working face of the retained entry side, which further ensures the filling effect of the goaf on the retained entry side, effectively limits the rotary sinking of blocks of the main roof, and greatly reduces effect on the stability of the retained entry.

An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

An assembly (7) for triggering an explosive in a hole (9) to produce an explosive blast in the hole includes (a) an explosion trigger (15, 19) for triggering the explosive in the hole, (b) a detonation unit body (21) that is configured to be located at or proximate an open end of the hole in an initial position of the assembly in the hole and (c) a trigger cord (31) that is connected to the detonation unit body and to the explosion trigger.

Apparatus and methods for preparing a blast hole in a rock face during a mining operation are disclosed. An exemplary method comprises: deploying a first tool toward the blast hole in the rock face via a common tool outlet of a feed unit using a first tool station of the feed unit; retracting the first tool from the common tool outlet using the first tool station of the feed unit and retaining the first tool in the first tool station; and while the first tool is retained in the first tool station, deploying a second tool toward the blast hole in the rock face through the common tool outlet of the feed unit using a second tool station of the feed unit.

Apparatus and methods for preparing a blast hole in a rock face during a mining operation are disclosed. An exemplary method comprises: deploying a first tool toward the blast hole in the rock face via a common tool outlet of a feed unit using a first tool station of the feed unit; retracting the first tool from the common tool outlet using the first tool station of the feed unit and retaining the first tool in the first tool station; and while the first tool is retained in the first tool station, deploying a second tool toward the blast hole in the rock face through the common tool outlet of the feed unit using a second tool station of the feed unit.