Shaft mining

The chute is a mining operations in mining, with which the deposit is being developed from the surface ( above ground ) ago. Shafts are used to transport people ( rope way) and material promoting the degradation products and the supply of fresh air ( ventilation ).

History

The first bays there were already more than 7500 years. From about 8 meters deep shafts flints were recovered in the mining process in small pits designed to veritable pit fields ( Grimes Graves). To get to the mine, the miners drove probably already on ropes through the slot. However, these wells remained only a short time in operation and have been, if the flint was mined, backfilled. This happened with the overburden of a shaft, which was further dug a few meters. A similar principle was also used in Duckelbau.

With the introduction of steam power, the technique of depth Bausch at night on a large scale was possible. The steam power was also necessary to pump out the accumulated in large masses groundwater inflows from the sump section. For extensive technical equipment such as boilers, steam engine, pulleys, etc. stronger shaft buildings were required. From these, the headframe has developed. Middle of the 15th century reached the shafts in the Mansfeld mining of metal ores already a depth of about 200 meters. In the 16th century have been created near Kitzbühel, underground mines, where the wells had a depth of about 880 meters.

Basics

Shafts are always required when a deposit is below the lug outsole, so no more tunneling is possible, or in support of the tunnel construction. The lowest point of a shaft is the shaft sump, the uppermost point of the pit bank. The pit bank is comparable in function to the tunnel mouth hole. Between pit bank and manhole sump, the individual soles depending on the deposit. The transition from the shaft tube to route calls to the miner shaft bell. In the region of the shaft bell, there is a special design shaft chair is called. The areas immediately adjacent to the shaft bottom part is called the fill location, here the horizontal line promotion is conducted into the shaft promotion. The shaft cross-section of a shaft with a shaft extension is called shaft washer. A shaft is usually divided into several departments. Each of these sections will be referred to as a run (including strand ), there is the accelerator, the Kunsttrum (also pipe or Leitungstrum ) and the conveying strands.

Loaded conveyor cage at the stop

Water retention in early civil engineering. Right of the conveyor shaft and left the art shaft with the pump art.

Subdivision by location

Shafts are created either cowardly (vertical) or tonnlägig. In the former ore mining shafts were created almost exclusively tonnlägig. These shafts follow the steeply inclined deposits (eg, veins ) and therefore deviate from the vertical. One advantage tonnlägiger shafts were the low investment costs, since the transition fill is usually softer than the surrounding rock. Due to the oblique approach of the deposit can be omitted alignment distances from the shaft to the disposal site. When ore mining could gain additional ores already while drilling, when Gangerzbergbau one learned in addition the Erzführung of the aisle know. A disadvantage tonnlägiger shafts is that the basket is lowered on wheels along guide rails, thus there is a higher rope wear.

Seigere shafts were indeed in creating more expensive than tonnlägige shafts, but have a longer operating period greater benefits. First, the shaft joints suffer a lower pressure than at tonnlägigen shafts. This allows the shaft lining is dimensioned smaller and the repair costs are not so large as in tonnlägigen shafts. In addition, the geteufte shaft length is less at the same depth at seigeren shafts. Today, usually only seigere shafts are created.

Use

Depending on how the wells were divided into a ventilation shaft, driving shaft, redrive shaft, conveyor shaft, Kunstschacht, alignment shaft, Pull shaft or main shaft.

Weather shafts are shafts, whose main task is to aeration ( ventilation ). Smaller Weather shafts that are used mainly drift mining, hot light holes.

Shafts that serve the biking the deeper mines were formerly called lift wells, today by internals partitioned from the conveying vehicle or Fahrentrum landing is sometimes called. Shafts that serve primarily to carry passengers, are now called rope drive shaft.

Bays, which serve to promote the materials, the minerals were formerly called redrive well or production well, now they are just called mine shaft. Bays, where an art boom was installed to raise the mine water, Kunstschacht were called.

Directional wells were used for alignment of the deposit. In the early Gangerzbergbau it was not customary to sink vertical ( saigere ) shafts. I.d.R. they were created in the incidence of the Ganges. As you about the 17-18. Century to over went to break down the deposits of scheduled, saigere shafts came into fashion. Since they were used for alignment of the deposit, they were called directional wells in order to flank from the other. So the miner says the term alignment shaft that it is a main shaft outside of the deposit, which is continuous - as opposed to the old tonnlägigen shafts with reel promotion that were dropped because manual reel creating less than 100 m head. Nowadays, there are actually only directional wells. Alignment shaft is a position and status of a shaft.

When a shaft combines all these tasks in itself, it is called the main shaft.

If the promotion of the ore was carried out by a reel with shafts, he was called Pull shaft or pull the shaft.

A shaft, which communicates with the earth's surface, called day shaft or Tagschacht. A blind shaft, however, is a shaft, which connects several soles just another " underground ". He does not lead to the light of day.

Shapes and dimensions,

Wells may be rectangular, oval or circular shaped. Round shafts have the advantage that with them the lateral rock pressure can be much better controlled by a shaft extension as with square shafts. The shaft diameter has increased over the years from an initial 1 to a maximum of 2 meters. Days later the wells already had a diameter of 2.5 to 4 meters. Today's shafts typically have a diameter of 8 meters. Since the shaft diameter has a large influence on the production capacity of the well, several factors should be considered when planning a well. First is crucial, which material needs, the mine and wants to promote through the corresponding slot. Additionally, the size and the weight of the material to be conveyed plays an essential role. In addition, it is decisive how many miners come to the cable ride.

The depth of a well depends on the depth of the exploitable deposit. Depending on the deposit -rich often pit depths of less than 100 meters from. Most of today's shafts have a depth of several hundred, sometimes more than a thousand meters. In one of the deepest mines in the world, the Western Deep Levels Mine, a weather slot has a depth of over 3000 meters.

Bay fixtures

Depending on the shaft type and shaft diameter are in the bay several components that serve the commissioning of the shaft, installed. In seigeren shafts special constructions of U-irons are built for the promotion, the miner called Einstein Riche. These plantains Once the track slats are attached. Furthermore, the brackets are installed for the reception of cables, pipes and the shaft as required.

In tonnlägigen shafts Schacht slats or Tonnlatten be to guide the shaft ton shaft rods, called built-in. These are shod with iron bars which are fixed to the footwall. For attachment of the shaft on the base rods special strong nails of iron are used. To change from one shaft to the other bar strand specific changes are installed, the. Bay with rails that are strong iron plates, are posted to the shaft rods

In Art shafts a rod to the rocker was installed, the shaft linkage or local linkage was called. The shaft linkage reached into the deepest pit, to him the smaller tie rods were attached.

Shaft

The sinking of a shaft is generally referred to as drilling, which today mainly manual and machine into the trench depth is meant. Shafts are sunk today by drilling and blasting. Before a well is sunk, the exact location of the shaft point approach is planned in advance. In loose water- bearing rock shafts with the freezing tray method are created in the presence of loose superficial layers the Senkschachtverfahren was in the 19th century sometimes applied.

By means of large-hole drilling wells can also be drilled in the full profile. The drills in this process are full cut machines such as those used in tunneling. Due to the size of the drill bits and the costs necessary Bohrgerüste the Schachtbohrverfahren is rarely applied. An example is the raise - boring process.

In an open-minded pit buildings shafts are broken up mechanically increased especially since the 20th century. The elaborate promotion of rock masses by above ground is omitted here, which makes this shaft construction method is very fast and inexpensive.

Throw off

Discarded shafts are generally held in safekeeping. This can be done by covering, filling or backfilling.

The former main method for shaft reclamation was the cover. The shaft opening a stage was either boarded with wood or sheet metal, or a few meters below the pit bank fed from a timber or vault and the shaft tube is filled up to ground level with gravel and soil. In such, according to present knowledge improperly backfilled or custody shafts, it often comes after years of Schachtverbruch, as the wood rots over time and the arch collapses or rust through the sheets. For this reason, this storage method is no longer used in modern times.

Shafts in the solid rock can be sealed. Is the long-term stability of the shaft tube is given, it is sufficient to close the upper part of the shaft tube with a seal made ​​of reinforced concrete. The seal is placed in the amount of solid rock and then filled up on days with gravel or mineral mixture.

Shafts in the solid rock not to be filled. A filling material is gravel or concrete. The Füllorte be removed before backfilling by dams from the mine. When using gravel occurs Nachsetzungen the Verfüllsäule. Therefore, a control and filling aperture is incorporated into the traffic load plate. The Verfüllspiegel is regularly controlled by the mine surveyor, at abandoned mines by the competent mining authority.

In the coal mining a Protegohaube is inserted into the lid for safe dissipation of mine gases.