A device includes a pressure measuring segment, a connecting rod, a hydraulic pump, a pressure gauge, a high-pressure oil pipe, a pressure control valve, a tray, a push rod and a connection casing. The pressure measuring segment is on the connecting rod, a front end of the push rod is connected with the connecting rod, the tray is at a rear end of the push rod, the connection casing is connected with the tray. The pressure measuring segment includes a main pipe, a hydraulic bladder, a fixing ring, a barrier sheet, an outer pillow housing and a connection sleeve. Both ends of the hydraulic bladder are sleeved on the main pipe, an oil inlet is in communication with the hydraulic bladder, the outer pillow housing is sleeved on the main pipe, the connection sleeve is wrapped around the outer pillow housing.

The present invention provides a retainer device 1 for retaining or holding an anchor rod 11 of a rock anchor, especially a self-drilling anchor, in a hole H drilled above horizontal. The retainer device 1 comprises: a body portion 2 configured to be mounted on the anchor rod 11, e.g., on an outer or external periphery of the anchor rod, and at least one locking arm or tab 6, 7 that projects from the body portion 2 in a direction transverse to a longitudinal extent of the anchor rod 11. The body portion 2 is configured to engage an abutment or shoulder on the outer or external periphery of the anchor rod to prevent its movement relative to the anchor rod 11 in use, and the at least one arm or tab 6, 7 is configured to deform so as to engage and bear against an inner wall W of the hole H when the retainer device 1 mounted on the anchor rod 11 is driven into the hole H. The invention also relates to a rock anchor system 10, comprising: at least one elongate anchor rod 11; a drill bit 12 configured for attachment to one end region 13 of the elongate anchor rod 11 for drilling the anchor rod 11 into rock strata R; and at least one retainer device 1 according to the invention described above for retaining or holding the anchor rod 11 in a hole H drilled in the rock strata R above horizontal. The invention also provides a method for installing a rock anchor.

The present invention provides a retainer device 1 for retaining or holding an anchor rod 11 of a rock anchor, especially a self-drilling anchor, in a hole H drilled above horizontal. The retainer device 1 comprises: a body portion 2 configured to be mounted on the anchor rod 11, e.g., on an outer or external periphery of the anchor rod, and at least one locking arm or tab 6, 7 that projects from the body portion 2 in a direction transverse to a longitudinal extent of the anchor rod 11. The body portion 2 is configured to engage an abutment or shoulder on the outer or external periphery of the anchor rod to prevent its movement relative to the anchor rod 11 in use, and the at least one arm or tab 6, 7 is configured to deform so as to engage and bear against an inner wall W of the hole H when the retainer device 1 mounted on the anchor rod 11 is driven into the hole H. The invention also relates to a rock anchor system 10, comprising: at least one elongate anchor rod 11; a drill bit 12 configured for attachment to one end region 13 of the elongate anchor rod 11 for drilling the anchor rod 11 into rock strata R; and at least one retainer device 1 according to the invention described above for retaining or holding the anchor rod 11 in a hole H drilled in the rock strata R above horizontal. The invention also provides a method for installing a rock anchor.

The present invention discloses a zero-gangue-discharge short-wall face pillar-free mining method, which is applicable to zero-gangue-discharge disposal in the mining operation in a mine shaft. A short-wall face is arranged in a selected area near a mine shaft according to the actual conditions of the mine shaft, the short-wall face is mined in a fully mining and fully back-filling mode, the gangues produced at other mining faces of the mine shaft are filled into the short-wall face, the short-wall face is supported with anchor rods along the edge of the filling face and the solid coal side to form an entry, and the entry is utilized to mine an adjacent working face. The method in the present invention mainly displaces the coal mass with gangues and thereby maximizes the utilization of the resources; in addition, the method can fully control the roof and realize mining without damage to the rock formation. Therefore, the method is of great value for wide application.

The present disclosure relates to an extendable apparatus, such as an extendable apparatus for a drill head, a drill head including an extendable apparatus, and a method of operating a drill head. The extendable apparatus includes a base section, a drive section, an extension section, and a functional section. The base section and the drive section are moveable with respect to the extension section and the functional section along a longitudinal axis. The drive section and the functional section are rotationally rigidly coupled to each other. The base section and the extension section are rotationally rigid coupled to each other, and the drive section and the functional section are rotationally moveably coupled to the extension section.

The present disclosure relates to an extendable apparatus, such as an extendable apparatus for a drill head, a drill head including an extendable apparatus, and a method of operating a drill head. The extendable apparatus includes a base section, a drive section, an extension section, and a functional section. The base section and the drive section are moveable with respect to the extension section and the functional section along a longitudinal axis. The drive section and the functional section are rotationally rigidly coupled to each other. The base section and the extension section are rotationally rigid coupled to each other, and the drive section and the functional section are rotationally moveably coupled to the extension section.

An apparatus for controllably unfolding a flexible mesh for a continuous miner includes a mesh roll storage rack, a height adjustment post, a mesh rolling shaft and a flexible mesh. The flexible mesh includes a mesh roll and an unfolded mesh. The mesh roll and the unfolded mesh are an integrated structure. The mesh roll is located on the mesh roll storage rack. The unfolded mesh is clamped on the mesh rolling shaft, and is pressed on a cut un-supported tunnel roof via a roof bolt. The mesh rolling shaft is rotatably connected to a top portion of the height adjustment post. The mesh roll storage rack and the height adjustment post are both mounted on the continuous miner. The mesh rolling shaft is located at a back end of the mesh roll storage rack. A limit mechanism and a damping mechanism are disposed on the mesh rolling shaft.

A drilling and bolting device for driving a drill element into a rock surface includes a frame, a drive unit supported for movement relative to the frame, and an actuator for moving the drive unit relative to the frame. The drive unit includes a motor and a chuck for engaging the drill element. The chuck is driven by the motor. In some aspects, the actuator includes a magnet exerting a magnetic force on the block to provide magnetic coupling between the actuator and a block supporting the motor. In some aspects, the actuator is positioned at least partially within an elongated member of the frame. In some aspects, the drive unit includes a switched reluctance motor including a stator and a rotor supported for rotation relative to the stator, and the rotor is directly coupled to the chuck.

A self-drilling rock anchor assembly includes: a friction fit tubular sleeve extending longitudinally between leading and trailing ends; a rod extending through the sleeve between first and second ends, and projecting from each sleeve end; a drill bit member engaged with the rod's first end having an exterior surface part of which tapers towards a back end of the member; a backstop element engaged with the rod's second end having a first drive surface; a load bearing element on the rod between the sleeve's trailing end and the backstop that has a second drive surface. The rod moves relative to the sleeve between a drill position, wherein the drill bit is spaced from the sleeve's leading end, and an insertion position, wherein the sleeve's leading end abuts the bit. The drill and insertion positions are achieved by applying a force to the first and second drive surfaces, respectively.

A self-drilling rock anchor assembly includes: a friction fit tubular sleeve extending longitudinally between leading and trailing ends; a rod extending through the sleeve between first and second ends, and projecting from each sleeve end; a drill bit member engaged with the rod's first end having an exterior surface part of which tapers towards a back end of the member; a backstop element engaged with the rod's second end having a first drive surface; a load bearing element on the rod between the sleeve's trailing end and the backstop that has a second drive surface. The rod moves relative to the sleeve between a drill position, wherein the drill bit is spaced from the sleeve's leading end, and an insertion position, wherein the sleeve's leading end abuts the bit. The drill and insertion positions are achieved by applying a force to the first and second drive surfaces, respectively.