- 行业: 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 ...
The timber, steel, brick, or concrete structure fixed around a shaft to support the walls. In modern shafts, a concrete lining is generally favored as a permanent shaft support.
Industry:Mining
The timbers composing any framing, whether used in a shaft, slope, level, or gangway. Thus, the four pieces forming a single course in the curbing of a shaft, or the three or four pieces forming the legs and collar, and sometimes the sill, of an entry framing are together called a set, or timber set.
Industry:Mining
The time between the application of an electric current and the setting off of an explosive charge. In seismic prospecting, it may be necessary to take into account the maximum difference in time lag between the bursting of the earliest and latest detonators in a series. In a series firing current of over 1 A direct current, the maximum difference with submarine seismic detonators is always less than 1 ms.
Industry:Mining
The time elapsing between two successive exposures of an aircraft camera when taking vertical photographs.
Industry:Mining
The time in which, through the employment of the available capital, the ore reserves--or such reasonable extension of the ore reserves as conservative geological analysis may justify--will be extracted.
Industry:Mining
The time interval between the appearance of two consecutive wave repetitions at a given point, usually expressed in seconds. The wave segments considered must be the same; i.e., the crests, troughs, etc.
Industry:Mining
The time it takes the scraper or truck to haul a load to the dumping area and return to position in the loading area.
Industry:Mining
The time necessary to make the separation into concentrate and tailing depends on such factors as particle size and reagents used, and must be known for determination of the size and number of flotation cells in the plant.
Industry:Mining
The time required for a dilute solution of hydrofluoric acid of a specific strength to etch the inside of an acid bottle enough so that the line of demarcation between the etched and unetched portions of the acid bottle is clearly discernible. Also known as etching time.
Industry:Mining
The time required for the dipper of a mechanical shovel to push through the bank and fill, swing to the haul unit, unload, and swing back to the digging position. Cycle time is established under standard conditions of a 90 degrees angle of swing and with an optimum depth of cut.
Industry:Mining
