- 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 grooved pulley wheel, mounted on plummer blocks, at the top of the headgear. The winding rope passes from a cage or skip around the sheave and onto the winding drum. For normal loads, the sheave rim and boss are made of castiron, and the spokes are made of round, mild steel. Winding sheaves range up to about 24 ft (7.32 m) in diameter. Sheaves up to 8 ft (2.44 m) in diameter are usually made in one piece, but above this size, they are built in halves and bolted together. To give efficient service, the sheave diameter should be at least 96 times the winding rope diameter.
Industry:Mining
A grooved pulley wheel, mounted on plummer blocks, at the top of the headgear. The winding rope passes from a cage or skip around the sheave and onto the winding drum. For normal loads, the sheave rim and boss are made of castiron, and the spokes are made of round, mild steel. Winding sheaves range up to about 24 ft (7.32 m) in diameter. Sheaves up to 8 ft (2.44 m) in diameter are usually made in one piece, but above this size, they are built in halves and bolted together. To give efficient service, the sheave diameter should be at least 96 times the winding rope diameter.
Industry:Mining
A ground-surveying instrument used in terrestrial photogrammetry, combining the functions of a theodolite and a camera mounted on the same tripod.
Industry:Mining
A group name comprising collinite and telinite. Differentiation between collinite and telinite depends in part on the method of observation. The distinction is more easily made in thin section or after etching a polished surface. Often there is uncertainty of distinction by reflected light, and in such cases, it is proper to use the general term vitrinite.
Industry:Mining
A group name for all authigenic, nonfluid bitumens; divided into stabile protobitumens and metabitumens.
Industry:Mining
A group name for bitumens that vary from gelatinous to hard resinous or elastic. Believed to represent an emulsion of highly acidic (humic acids) hydrocarbons with a varying amount of water (as high as 90%). Insoluble in organic solvents.
Industry:Mining
A group name for dark-colored hypabyssal or extrusive rocks rich in potassium and magnesium; also, any rock in that group, such as madupite, orendite, fitzroyite, verite, cedricite, or wyomingite.
Industry:Mining
