- 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 ...
A system of gears, ratchets, and friction devices, or some combination of these parts, in the swivel head of a diamond drill, which controls the rate at which a bit is made to penetrate the rock formation being drilled. When controlled by a feed gear, the bit maintains the same penetration rate per revolution regardless of drill-stem revolutions per minute.
Industry:Mining
A system of geophysical prospecting based on measuring underground temperatures or temperature gradients and relating their irregularities to geological deformation.
Industry:Mining
A system of haulage (usually endless rope) in which the engine is installed on the surface, and the power is transmitted to the haulage drums at the pit bottom by means of a rope, which is known as a strap rope, or a driving rope. This rope merely transmits power and is distinct from the haulage rope.
Industry:Mining
A system of haulage in which the set of full cars is lowered at the end of a rope, and gravity force pulls up the empty cars, the rope being passed around a sheave at the top of the incline. The speed of the haulage is controlled by a band brake on the sheave.
Industry:Mining
A system of haulage in which the set of full cars is lowered at the end of a rope, and gravity force pulls up the empty cars, the rope being passed around a sheave at the top of the incline. The speed of the haulage is controlled by a band brake on the sheave.
Industry:Mining
A system of haulage in which the set of full cars is lowered at the end of a rope, and gravity force pulls up the empty cars, the rope being passed around a sheave at the top of the incline. The speed of the haulage is controlled by a band brake on the sheave.
Industry:Mining
A system of leasing practiced at Cripple Creek, Colorado, whereby the miners and company divide the profits.
Industry:Mining
A system of longwall stalls in which the faces are carried forward in a steplike formation, one stall about 5 yd (4.6 m) in advance of the next stall. It is claimed to have advantages when the roof is friable.
Industry:Mining
A system of longwall working in which the developing headings are driven narrow to the boundary or limit line and then the coal seam is extracted by longwall faces retreating toward the shaft. In this method, all the roadways are in the solid coal seam and the waste areas are left behind.
Industry:Mining
