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United States Bureau of Mines
Industry: Mining
Number of terms: 33118
Number of blossaries: 0
Company Profile:
The U.S. Bureau of Mines (USBM) was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources. Founded on May 16, 1910, through the Organic Act (Public Law 179), USBM's missions ...
Obsolete syn. for a triclinic crystal system.
Industry:Mining
Consists of wooden staves driven down in soft ground during sinking to keep back water. The lining is stated to be capable of withstanding pressures up to a maximum of 130 psi (896 kPa). The lining resembles the sides of a wooden tub and the word tubbing is doubtless derived from this similarity.
Industry:Mining
Coal-cutting machine that is an adaptation of a shortwall machine, designed to make the cut, or kerf, at desired place in the coal seam some distance above the floor. The main difference between an overcutting machine and an ordinary shortwall machine is that the cutter bar in the overcutting machine is mounted at the top of the machine instead of at the bottom.
Industry:Mining
Hoisting in a deep shaft with two skips running in one shaft. The lower skip is suspended from the tail rope of the upper skip. Both are loaded and discharged simultaneously. The upper one discharges at the surface and is loaded at a pocket halfway down the shaft. The lower skip is loaded at the shaft bottom and discharges at the half-way pocket. Thus, the rope on the winding drum is only equal to half the full depth.
Industry:Mining
Clay found under a coalbed, usually a fireclay.
Industry:Mining
In the underground gasification of coal, a borehole is drilled to a blind end having no outside connection. A tube of smaller diameter is inserted nearly the full length through which air is passed to supply a gasification reaction at the far end of the hole. The hot gases return around the outside of the tube.
Industry:Mining
Generally 500 to 3,000 ft (152 to 915 m) in length. It is used to transport material between the gathering conveyor and the outside. Haulage conveyors are commonly classified as either intermediate or main haulage conveyors.
Industry:Mining
In mining, portion of underground workings sealed off, usually because of fire (in which case no air is allowed to enter) or because no mineable coal remains in the area.
Industry:Mining
Curved length of steel, usually of H-section, used for supporting mine roadways. Two-, three-, or four-segment arches are available, with straight leg, splayed leg, horseshoe, or circular design; in double radius or with welded baseplate.
Industry:Mining
Minerals included in a lode or vein, including economically valueless gangue.
Industry:Mining