A ventilation method for a high gas working face based on alternating intake and air return in a mine gallery is provided. In this method, an isolated island working face is divided into several sections along a strike direction. A coal pillar is alternately set as a conventional section and a gas-drainage section. Opposite coal pillars in the two mine galleries within the same section are respectively used as the conventional section and the gas-drainage section. Two mine galleries on both sides of the isolated island working face are alternately used as an intake gallery and a return gallery. The coal pillar at the side of the mine gallery as the return gallery is the gas-drainage section. A gas-drainage hole communicating a goaf is provided in the gas-drainage section, so that gas in the goafs at two sides of the isolated island working face can be extracted alternately.

A mine door system which includes a mine door having a door leaf, and a door-moving mechanism that articulates between a first configuration in which the mechanism applies a relatively smaller door-moving force to the door leaf and moves it at a first speed and a second configuration in which the mechanism applies a larger door-moving force to the door leaf and moves it at a second speed less than the first speed.

A mine door system which includes a mine door having a door leaf, and a door-moving mechanism that articulates between a first configuration in which the mechanism applies a relatively smaller door-moving force to the door leaf and moves it at a first speed and a second configuration in which the mechanism applies a larger door-moving force to the door leaf and moves it at a second speed less than the first speed.

A reinforced lightweight mine door for installation in a mine passageway. The mine door includes a generally rectangular sheet metal door panel having four sides and four corners, and a reinforcing structure projecting from a face of the door panel. The reinforcing structure has a central section and a plurality of channel sections extending from the central section toward respective sides or corners of the door panel. A mine door including at least one hinge arrangement having unique reversibility features is also disclosed.

A reinforced lightweight mine door for installation in a mine passageway. The mine door includes a generally rectangular sheet metal door panel having four sides and four corners, and a reinforcing structure projecting from a face of the door panel. The reinforcing structure has a central section and a plurality of channel sections extending from the central section toward respective sides or corners of the door panel. A mine door including at least one hinge arrangement having unique reversibility features is also disclosed.

A longitudinally yieldable support for underground roof support includes an elongate outer shell filled with a solid compressible filler material. At least one air ventilation tube extends between opposite sides of the support to allow a flow of air through the support as the support yields.

A longitudinally yieldable support for underground roof support includes an elongate outer shell filled with a solid compressible filler material. At least one air ventilation tube extends between opposite sides of the support to allow a flow of air through the support as the support yields.

A personnel access door assembly of an opposing wing of a mine ventilation door. The personnel access door includes a frame including a top portion, a bottom portion, a first post portion and a second post portion, the top frame portion and the bottom frame portion coupled to respective top and bottom ends of the first post and second post portions. The personnel access door further includes sets of trolley wheels affixed to the top or bottom of the frame to engage a top rail or bottom rail affixed on the opposing wing.

Example inflatable air barriers are disclosed herein. Some example barriers disclosed herein include one or more inflatable tubes for maintaining a sealed airlock leading to an underground shelter. Such shelters provide miners with temporary refuge in the event of a mining incident involving the release of contaminated air. Some example barriers disclosed herein include one or more of the following: an inflatable tube with an air permeable section, a resiliently compressible foam body or other resilient member for supporting a deflated tube, a magnet for providing a secure seal, an inflatable tube with interchangeable end caps, elastic bands for securing the position of an inflatable tube, or an inflatable tube with one or more windows.

Example inflatable air barriers are disclosed herein. Some example barriers disclosed herein include one or more inflatable tubes for maintaining a sealed airlock leading to an underground shelter. Such shelters provide miners with temporary refuge in the event of a mining incident involving the release of contaminated air. Some example barriers disclosed herein include one or more of the following: an inflatable tube with an air permeable section, a resiliently compressible foam body or other resilient member for supporting a deflated tube, a magnet for providing a secure seal, an inflatable tube with interchangeable end caps, elastic bands for securing the position of an inflatable tube, or an inflatable tube with one or more windows.