Disclosed is a method for designing supporting parameters of a transition support for a mixed mining face of filling and fully-mechanized mining. The method includes: first, determining a total length of a mixed mining working face and a length of a filling section according to requirements of a coal mining production capacity of the mixed mining working face and a filling capacity of the filling section working face; then, establishing a mixed mining numerical model of filling and fully-mechanized mining by using three-dimensional distinct element software, and simulating and calculating a caving height of a roof of a transition section and a stress influence range of the transition section when a filling rate of a mined-out area of the filling section changes; based on a result of numerical simulation and calculation, performing curve fitting according to a correlation coefficient to obtain a functional relationship between the filling rate and the caving height and a functional relationship between the filling rate and the stress influence range of the transition section; and finally designing supporting parameters of a transition support in combination with actual engineering geological parameters. The method can provide a reference for supporting design of a support, and enables a smooth transition between a filling support and a fully-mechanized mining support for a mixed working face, thereby further enriching filling mining theories and expanding the application range of filling mining.

An active temporary roof support apparatus for attachment to a mining machine includes at least one set of support members, each set including at least a first support member and a second support member for supporting the roof of an underground tunnel. A drive assembly is arranged to drive the set of support members, such that the first and second support members are sequentially moved for engaging the roof so that the roof is supported by at least one support member during an excavation operation of the mining machine. A mining machine and a corresponding method is also provided.

A grout tillable prop assembly for supporting a ceiling such as the ceiling of an underground mine. The prop assembly comprising an inner member and an outer member adapted for movement between an extended use configuration and a retracted configuration, a unidirectional grout inlet in an upper part of a sidewall of the outer member to allow grout to pass into the prop, the inner member and the outer member having wall portions and being self-supporting, an air conduit through the prop having an opening adjacent an upper limit of the prop, a pressure relief valve coupled to the air conduit whereby the prop is be brought from the retracted configuration to the extended configuration by application of pressurized air through the air conduit and whereby the extended prop is filled with grout via the unidirectional grout inlet.

A distributed coal cutting device for a Longwall face of a coal mine includes coal cutting units, where each coal cutting unit includes one coal cutting machine and two hydraulic supports, the two hydraulic supports are arranged side by side, the arrangement direction of the two hydraulic supports is parallel to the coal wall of the Longwall face, and the coal cutting machine is connected with one of the hydraulic supports. According to the device, multiple coal cutting machines are used for simultaneously carrying out coal cutting operation, and single-point coal cutting is changed into multiple-point simultaneous coal cutting, so that the coal cutting production capacity and the production efficiency are greatly improved. The multiple coal cutting machines can derive multiple control modes, so that the production flexibility and adaptability are improved.

A method of controlling a longwall mining system, the longwall mining system including a longwall shearer, a conveyor, and a plurality of roof supports, such that the method includes creating, by a controller, a load profile of the conveyor representing a distribution of mineral along a length of the conveyor, calculating, by the controller, a desired change in the load profile based on the load profile of the conveyor, and controlling, by the controller, the longwall mining system to adjust the distribution of mineral on the conveyor based on the desired change in load profile.

Disclosed is a method for designing supporting parameters of a transition support for a mixed mining face of filling and fully-mechanized mining. The method includes: first, determining a total length of a mixed mining working face and a length of a filling section according to requirements of a coal mining production capacity of the mixed mining working face and a filling capacity of the filling section working face; then, establishing a mixed mining numerical model of filling and fully-mechanized mining by using three-dimensional distinct element software, and simulating and calculating a caving height of a roof of a transition section and a stress influence range of the transition section when a filling rate of a mined-out area of the filling section changes; based on a result of numerical simulation and calculation, performing curve fitting according to a correlation coefficient to obtain a functional relationship between the filling rate and the caving height and a functional relationship between the filling rate and the stress influence range of the transition section; and finally designing supporting parameters of a transition support in combination with actual engineering geological parameters. The method can provide a reference for supporting design of a support, and enables a smooth transition between a filling support and a fully-mechanized mining support for a mixed working face, thereby further enriching filling mining theories and expanding the application range of filling mining.

Systems and methods are provided for detecting face alignment and face steering of a longwall mining system. The system includes a detection device mounted in a maingate roadway and a first indicator device mounted on a shearer of the longwall mining system to indicate a position of the shearer to the detection device. The system further includes a controller coupled to the detection device. The controller determines a shearer path of the shearer as the shearer moves along an ore face. The shearer path is determined based on a signal from the first indicator device received by the detection device. The controller generates an indication of face alignment based on the shearer path.

A wear pad for a longwall mining shield base lift. The wear pad includes at least one spanner hole for rotating the wear pad with a lever, at least one threaded retaining hole, and a retaining bolt threaded through the retaining hole until it contacts a cylinder rod to which the wear pad is to be attached.

A method for removing a hydraulic support for solid filling coal mining includes digging a support removing channel (3) in a coal body (2) in front of the hydraulic support (1), and laying a support removing track (4), then removing the hydraulic support from a coal conveying gateway (11) to a track gateway (5), temporary supporting is carried out by matching a single supporting column with a n-type steel beam before each hydraulic support is removed. A supporting roof is reinforced in time by means of erecting a crib (13) and grouting after each hydraulic support is removed, three grouting pipelines (12) are laid after the supports of the whole work surface are removed, and grouting is carried out in the whole finishing cut space. The roof of the support removing space of the work surface is stable so that the hydraulic supports on the work surface of solid filling coal mining are ensured to be safely and efficiently removed.

A fluid spray for an underground roof support includes a first housing portion, a spray outlet, a second housing portion formed integrally with the first housing portion, and a service port. The first housing portion includes an elongated shaft having a first end, a second end, and a first fluid passage extending between the first end and the second end. The spray outlet is positioned adjacent the second end of the shaft. The second housing portion is positioned adjacent the first end of the shaft. The second housing portion includes at least one port and a second fluid passage between the at least one port and the first fluid passage. The service port is aligned with the first fluid passage, and the service port is selectively opened to provide access to the first fluid passage from the first end of the first housing portion.