- 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 ...
This is a type of sensor that measures bursts of high-energy electromagnetic waves that are emitted spontaneously by some naturally occurring radioactive elements, such as potassium-40, thorium-232, and uranium-238, that are commonly present in shales and clays.
Industry:Mining
This is found by the formula: water content of test sample-water content at plastic limit/index of plasticity. This gives a value of 100% for clay at the liquid limit, and zero at the plastic limit, and is the reverse of the consistency index.
Industry:Mining
This is measured in a calibrated glass bottle with special precautions against the inclusion of air. Such testing is applied in many soil problem computations.
Industry:Mining
This is the region in which, if a sufficient quantity of explosive is used, the rock will be shattered and projected outward to form a crater.
Industry:Mining
This is the zone of additional stress in the rock surrounding and caused by a stoped area.
Industry:Mining
This kit is designed to prevent coal-dust explosions. It helps to determine the explosion hazard prior to rock dusting, the fineness of the rock dust as it comes from the pulverizer, and the percentage of combustible matter present in rock and coal dust mixtures after rock dusting.
Industry:Mining
This lamp consists of a flat portable battery that is strapped around the miner's waist and is connected by an insulated cord to a small electric light and reflector that is fastened on the front of the miner's cap.
Industry:Mining
This lower oxide, FeO, tends to be formed under reducing conditions; it will react with SiO<sub>2</sub>to produce a material melting at about 1,200 degrees C, hence the fluxing action of ferruginous impurities present in some clays if the latter are fired under reducing conditions. Melting point, 1,420 degrees C; sp gr, 5.7.
Industry:Mining
This machine comprises a number of horizontal rotating flight bars working near the floor of the seam and driven through gearing by an electric motor. These bars push into the coal in their extended position and are almost completely concealed inside the loader casing in their retracted position. They push prepared coal up a ramp on to a low, bottom-loaded conveyor belt. The machine is hauled along the face by means of two steel ropes wound on separate drums on the loader; one rope passes up the front of the coal and is held by means of an anchor prop; the other rope is threaded under the cut coal by means of a threader pipe attached to the rear of the coal cutter. Lengths of rope equal to the drum capacity are joined by figure-8 links and are detached and unwound from the drum as the loader proceeds along the face.
Industry:Mining
This machine consists essentially of two horizontal cutting chains, one working at the base of the coal seam and the other at a distance from the floor; a third cutter chain is mounted vertically on a shearing jib at right angles to the other two and shears off the coal at the back of the cut. The upper jib breaks the coal up into loadable size, and a short conveyor transfers it to the face conveyor. Similar in principle to the A.B. Meco- Moore cutter-loader.
Industry:Mining
