SHAFT MINING

(Redirected from Mine shaft)
Abandoned mine shafts in Marl, Germany.

A plan-view schematic of a mine shaft showing cage and skip compartments. Services may be housed in either of the four open open compartments.

'Shaft mining' or 'Shaft sinking' refers to the method of excavating a vertical or near-vertical tunnel from the top down, where there is initially no access to the bottom.
[1]
When the top of the excavation is surface it is refered to as a shaft, when the top of the excavation is underground it is called a ''winze''.

Contents
Off-shaft Access
Surface facilities
Shaft lining
Shaft compartments
See Also
Notes and references
External Links

Off-shaft Access


The mine shaft is used to access to an underground mining facility. Horizontal workings off the shaft are called drifts, galleries or levels, these extend from the central shaft towards the ore body. The point of contact between these levels and the shaft itself is known as the inset, or shaft station.

Surface facilities


On the surface above the shaft stands a building known as the headframe (or poppet head or pit head). Depending on the type of hoist used the top of the headframe will either house a hoist motor or a sheave wheel (with the hoist motor mounted on the ground).
The headframe will also contain bins for storing ore being transfered to the processing facility. If the shaft is used for mine ventilaton a plenum or casing, is incorporated into the headframe to ensure the proper flow of air into and out of the mine.

Shaft lining


In North and South America, smaller shafts are designed to be rectangular with titmber supports. Larger shafts are round and are concrete lined.
[2]

Shaft compartments


A mine shaft is split into multiple compartments. The largest compartment is used for the cage, a conveyance used for moving workers and supplies below the surface. It functions in a similar manner to an elevator. The second compartment is the skip, used to transport ore to the surface. Smaller mining operations use a skip mounted underneath the cage, rather than a separate device. The third compartment is used for an emergency exit; it may house an auxiliary cage or a system of ladders. An additional compartment houses mine services such as high voltage cables and pipes for transfer of water, compressed air or diesel fuel.

See Also



Underground mining (hard rock)

Drift mining

Notes and references


1. Underground Drilling and Loading Handbook, , Tuula (editor), Puhakka, Tamrock Corp., ,
2. Hard Rock Miner's Handbook, Edition 3, , Jack, De la Vergne, McIntosh Engineering, ,

External Links



Abandoned Mine Shafts & Tunnels

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