Search results
Results from the WOW.Com Content Network
A man engine is a mechanism of reciprocating ladders and stationary platforms installed in mines to assist the miners' journeys to and from the working levels. It was invented in Germany in the 19th century and was a prominent feature of tin and copper mines in Cornwall until the beginning of the twentieth century.
In slope mining, the primary access to the mine is on an incline. Mine hoists may still be used to raise and lower loads on the incline if it is steep, but on shallower slopes, conveyor belts, locomotives or trucks may do the work. Drainage and ventilation of slope mines may be done using the primary slope, or it may be done using auxiliary ...
The ladder has handrails on both sides for safety. Accommodation ladders are constructed in such a way that the steps are horizontal whatever the angle of inclination of the ladder. The lower end the ladder/lower platform is based on a roll to compensate for the motion of the ship in relation to the quay.
Fall protection system: Fixed ladders above 24' must have a fall protection system in accordance with OSHA Standard 1910.28(b)(9)(i)(C). Cages are not anymore considered as fall protection, and ladders that are newly installed or replaced after November 19, 2018, must have a fall protection system based on OSHA's new fixed ladder requirements.
Mine surveying is the practice of determining the relative positions of points on or beneath the surface of the earth by direct or indirect measurements of distance, direction & elevation. [ 1 ] International and National Institutions
This can be expressed in the distance traveled horizontally for a rise of one unit, or in terms of an angle of inclination or a percentage difference in elevation for a given distance of the track. The allowable gradients may be based on the ruling gradient which is the maximum gradient over which a tonnage train can be hauled with one locomotive.
An extension ladder. A ladder is a vertical or inclined set of rungs or steps commonly used for climbing or descending. There are two types: rigid ladders that are self-supporting or that may be leaned against a vertical surface such as a wall, and rollable ladders, such as those made of rope or aluminium, that may be hung from the top.
A drift mine is an underground mine in which the entry or access is above water level and generally on the slope of a hill, driven horizontally into the ore seam. [ 2 ] Drift is a more general mining term, meaning a near-horizontal passageway in a mine, following the bed (of coal, for instance) or vein of ore.