659:. The activities of the sinking cycle (excavation, installation of temporary ground support, placement of the shaft lining and extending shaft services) all take place in this phase of construction. In a shaft where there are to be multiple working levels, shaft stations and station stubs (short lengths of a horizontal tunnel leading away from the station) will be developed by the sinkers on the way down. As the equipment to excavate these stations must be small enough to fit through the openings in the Galloway, the rate of advance in developing the station stubs is typically low, compared to what can be achieved with full-size mining equipment, so station stubs are typically kept as short as possible.
229:
615:. The pre-sink is the excavation and support of the first 60 – 100 metres of the shaft barrel, often completed with smaller equipment such as handheld, pneumatic drilling equipment to drill holes for basting and ground support and mini-excavators for mucking. During the pre-sink, hoisting of muck and equipment is usually performed by a mobile crane on the surface. It is necessary to sink this part of the shaft first so that the Galloway, a multi-level working platform may be installed with enough vertical distance to the shaft bottom that it will not be damaged by
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means of winches, which move slowly and are rated for significant loads, while the sinking buckets (or kibbles) are moved in the shaft by the sinking hoist, which moves quickly and is rated for less load than the winches. To protect the hoist(s) and winches and the sensitive electronics which are used to control their operation they are normally installed inside a build called a hoist (or winder) house.
600:
down to bedrock, inside which the shaft collar will be constructed. Having the loads imposed by the collar, headframe and hoisting plant transferred into solid rock is necessary to prevent unplanned subsidence. Where the depth of bedrock is too great to for a box cut to be economically viable, or the
570:
as the project team repeats the same series of activities over and over in what is called "the sinking cycle", eventually approaching the theoretical maximum rate for that sinking set up over time. The use of experienced shaft sinkers is necessary to reduce the length of this learning curve and thus
665:
Once the shaft reaches the final design depth, the shaft is stripped of any temporary services, the
Galloway cut up or modified to suit the installation of the permanent shaft set-up, the shaft sets (if required) installed and the headframe / winders modified to allow for permanent hoisting. Any
646:
With the collar constructed and the
Galloway installed the headframe and hoist (or winder) houses may be constructed and the hoist and winch ropes installed. Headframes may be either steel or concrete and their design will determine how they are constructed. The Galloway is moved in the shaft by
421:
The shaft liner does not reach right to the bottom of the shaft during sinking, but lags behind by a fixed distance. This distance is determined by the methodology of excavation and the design thickness of the permanent liner. To ensure the safety of persons working on the shaft bottom temporary
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Traditionally, sinking contractors would build a temporary headframe for the sinking set-up, which would then be dismantled to make way for a permanent headframe. With the growth in complexity and duration of shaft sinking projects over time it has become more common to incorporate more of the
437:
For this reason, and to minimise the number of persons on the shaft bottom a number of projects have successfully switched to shotcrete for this temporary lining. Research and development in this area is focusing on the robotic application of shotcrete and the commercialisation of thin sprayed
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located on the surface. The
Galloway allows sinkers to efficiently work on different levels as required by the various tasks of the sinking cycle. It is typical for the Galloway to be constructed off to one side of the shaft and lowered into the pre-sink with a crane in as complete a state as
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At ground level beneath and around the headframe is the Shaft Collar (also called the Bank or Deck), which provides the foundation necessary to support the weight of the headframe and provides a means for workers, materials and services to enter and exit the shaft. Collars are usually massive
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With the advancements made in raise boring technology, raise borers have been used to create a pilot hole for shaft sinking, where access exists at the bottom of the new shaft, in this case the sinking phase is dedicated to enlarging this pilot hole to full diameter (a process usually called
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to the surface. Smaller mining operations use a skip mounted underneath the cage, rather than a separate device, while some large mines have separate shafts for the cage and skips. The third compartment is used for an emergency exit; it may house an auxiliary cage or a system of ladders. An
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Final choice of shaft lining is dependent on the geology of the rock which the shaft passes through, some shafts have several liners sections as required Where shafts are sunk in very competent rock there may be no requirement for lining at all, or just the installation of welded mesh and
380:. The shaft lining performs several functions; it is first and foremost a safety feature preventing loose or unstable rock from falling into the shaft, then a place for shaft sets to bolt into, and lastly a smooth surface to minimise resistance to airflow for ventilation.
128:), dimensions and depth of mine shafts vary greatly in response to the specific needs of the mine they are part of and the geology they are sunk through. For example, in North and South America, smaller shafts are designed to be rectangular in plan view with
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and top hat sections. Top hat sections offer a number of advantages over hollow structural sections including simpler installation, improved corrosion resistance and increased stiffness. Mine conveyances run on the guides in a similar way to how a
78:
Shaft sinking is one of the most difficult of all mining development methods: restricted space, gravity, groundwater and specialized procedures make the task quite formidable. Shafts may be sunk by conventional drill and blast or mechanised means.
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permanent shaft set-up into the sinking phase. This results in a reduced overall project duration, as for example, if the service piping used to sink the shaft does not need to be stripped out to make way for permanent piping.
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A shaft may be either vertical or inclined (between 80 and 90 degrees to the horizontal), although most modern mine shafts are vertical. If access exists at the bottom of the proposed shaft, and ground conditions allow, then
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Although significant emphasis is placed on the rate of progress of a project sinking cycle by shaft sinkers, sinking is only one of a number of phases in the conventional construction of a new shaft, as follows;
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The lowest point in a sinking shaft is known as the "shaft bottom". Shaft projects differ from some other forms of mine development in that all activities that take place on the shaft bottom become part of the
209:". Many other global mining jurisdictions have adopted this rule and shafts are therefore often found in pairs (although there are multiple alternative methods of providing a second means of egress).
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where the single shaft at the mine became blocked, the United
Kingdom made single shaft mines illegal in 1862, establishing the practice that all underground mines must have a "
540:. One or more of the compartments discussed above may be used for air intake, while others may be used for exhaust. Where this is the case a steel or concrete wall called a
105:
The modern shaft sinking industry is gradually shifting further towards greater mechanisation. Recent innovations in the form of full-face shaft boring (akin to a vertical
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505:, a conveyance used for moving workers and supplies below the surface, which is suspended from the hoist on steel wire rope. It functions in a similar manner to an
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wheel (with the hoist motor mounted on the ground). The headframe will also typically contain bins for storing ore being transferred to the processing facility.
289:, sometimes for many kilometers. The lowest shaft station is most often the point where rock leaves the mine levels and is transferred to the shaft, if so a
139:
Mine shafts may be used for a variety of purposes, including as a means of escape in the event of an emergency underground and allowing for the movement of:
285:(or inset) which allows men, materials and services to enter and exit the shaft. From the station tunnels (drifts, galleries or levels) extend towards the
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possible. Once in place, the
Galloway is "chaired" (suspended from the shaft collar) while the headframe is built above, often protected by a bulkhead.
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As with the depth and design of shafts, significant variations may exist in this sequence depending on local conditions. For example, shafts in the
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It is typical for progress (the "sinking rate") in the sinking phase (that is excavation, ground support and lining) of a shaft project to follow a
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Historically, mine shaft sinking has been among the most dangerous of all the mining occupations and the preserve of mining contractors called
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typically connects the bottom of the shaft with the rest of the mine, this ramp often contains the mine's water handling facility, called the
180:. Small shafts may be excavated upwards from within an existing mine as long as there is access at the bottom, in which case they are called
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The
Permanent set-up must then be commissioned to ensure that all parts are operating as planned before being handed over to the new owner.
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A plan-view schematic of a mine shaft showing cage and skip compartments. Services may be housed in either of the four open compartments.
509:. Cages may be single-, double-, or rarely triple-deck, always having multiple redundant safety systems in case of unexpected failure.
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is installed between the two compartments to separate the air flow. At many mines there are one or more complete additional separate
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696:(waste rock) from sinking falls down the pilot hole and is handled using existing mine infrastructure off critical path.
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The
Galloway (also known as a Sinking Stage or Scaffold) is a multi-level working platform, suspended in the shaft from
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and even squash balls have been required by specific circumstances. In extreme cases, particularly when sinking through
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du Judeel, G; Keyter and Harte (April 2012). "Shaft Lining design for a potash shaft in rock salts at large depths".
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121:, which are "sunk" as a means of accessing an underground ore body, during the development of an underground mine.
629:. From the bottom of the box cut, the shaft collar is constructed bottom up in a planned series of concrete pours.
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is both strong and close to the surface. This reduces the amount of time required to establish the shaft collar.
220:, which has a depth of 2991 meters. Along with its twin ventilation shafts, it took ten years to sink and equip.
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for the project schedule. The infrastructure required to sink a shaft is referred to as "the sinking set-up".
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is the action of excavating a mine shaft from the top down, where there is initially no access to the bottom.
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430:) is among the most physically challenging parts of the shaft sinking cycle as bolts must be installed using
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Beneath the lowest shaft station the shaft continues on for some distance, this area is referred to as the
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or casing is incorporated into the collar to ensure the proper flow of air into and out of the mine.
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247:(or winding tower, poppet head or pit head) which stands above the shaft. Depending on the type of
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is excavated on one side of the shaft at this location to allow transfer facilities to be built.
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Where the shaft is to be used for hoisting it is frequently split into multiple compartments by
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Many (although not all) shafts are lined following excavation and the installation of temporary
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The
Sinking set-up must then be commissioned to ensure that all parts are operating as planned.
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Getting the various components of the sinking set-up correct and installed at the right time.
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Sanders, D. (April 2012). "New
Waterproofing Technologies for Vertical Shaft Construction".
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segments have all been used at one time or another. Additionally, the use of materials like
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Currently, the deepest continuous single-lift mine shaft in the world is the main shaft at
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Beneath the collar the part of the shaft which continues into the ground is called the
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Mine services (such as compressed air, water, backfill, power, communications and fuel)
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939:"Sinking Contractor's Close Out Presentation on the completion of South Deep Shafts"
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692:"slashing"). This methodology can be considerably faster than full face sinking as
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596:. A box cut is a large square or rectangular excavation typically completed using
388:. The material of choice for shaft lining is mass concrete which is poured behind
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projects, differ greatly in execution method from deep shafts, typically sunk for
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251:(or winder) used, the top of the headframe will either house a hoist motor or a
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Some shafts do not use guide beams but instead utilize steel wire rope (called
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may be used to excavate the shaft from the bottom up; such shafts are called
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When the top of the excavation is the ground surface, it is referred to as a
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Having experienced people involved from as early in the project as possible
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Process of excavating a vertical or near vertical tunnel from the top down
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runs on its rails, both having wheels which keep them securely in place.
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At locations where the shaft barrel meets horizontal workings there is a
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Using the available time on the shaft bottom as efficiently as possible.
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236:, Katowice. Currently functioning as observation tower and part of the
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The most visible feature of a traditionally-built mine shaft is the
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bedrock is not strong enough, civil engineering techniques such as
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ground support is installed, usually consisting of welded mesh and
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or wheel of cheese) as these are easier to maintain and replace.
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Proceedings of the Third South
African Conference on Base Metals
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generally do not need a deep and complex shaft collar since the
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structures with more than one level. If the shaft is used for
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490:) kept in tension by massive weights at shaft bottom called
426:. The installation of the temporary ground support (called
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843:"Case Study - Blind Shaft Sinking for BHP Jansen Project"
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Galloway (Sinking Stage) Construction & Installation.
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Repurposing old mine shafts for energy storage purposes
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permanent conveyances will be installed at this stage.
86:. Today shaft sinking contractors are concentrated in
860:
Gleeson, D (September 2018). "That Sinking Feeling".
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in lifts of 6 m as the shaft advances (gets deeper).
521:
additional compartment houses mine services such as
474:. For steel shaft guides, the main two options are
501:The largest compartment is typically used for the
454:Typical mine cage, located in Harzbergbau, Germany
132:supports. Larger shafts are round in plan and are
571:the duration of the project as much as possible.
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609:may be used to create a deep foundation instead.
30:"Mineshaft" redirects here. For other uses, see
574:Key to a successful shaft sinking project are:
512:The second compartment is used for one or more
817:"A Glossary of Mining Terms used in mid 1800s"
795:. John Wiley and Sons Inc. pp. 282, 284.
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466:. Vertical members in a shaft set are called
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663:Shaft Equipping & Headframe Changeover.
536:A second reason to divide the shaft is for
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117:Mine shafts are vertical or near-vertical
774:Underground Drilling and Loading Handbook
644:Headframe & Hoist House Construction.
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890:: McIntosh Engineering. p. 92.
155:Broken rock (in the form of payable
998:Abandoned Mine Shafts & Tunnels
913:"Work: The Hartley Mining Disaster"
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747:Glossary of coal mining terminology
550:with separate head gear and cages.
494:(because of their resemblance to a
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875:De la Vergne, Jack (August 2003).
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525:and pipes for transfer of water,
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945:: 455 – via Academia.edu.
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958:Shaft Design and Construction
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651:Commissioning Sinking Set-Up.
780:: Tamrock Corp. p. 173.
772:Puhakka, Tuula, ed. (1997).
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791:Hartman, Howard L. (2002).
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841:Rennkamp, P (2019).
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300:. A tunnel called a
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937:Douglas, A (2005).
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921:, retrieved
916:
906:
876:
870:
861:
855:
846:
836:
824:. Retrieved
820:
811:
792:
786:
773:
767:
712:Engine shaft
707:Drift mining
690:
686:
675:
669:
662:
656:
650:
643:
632:
626:
612:
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547:
541:
535:
511:
502:
500:
491:
487:
485:
471:
467:
459:
457:
436:
427:
420:
406:tubing, and
394:
389:
382:
375:
323:
314:Shaft lining
305:
301:
298:shaft bottom
297:
295:
290:
282:
280:
276:shaft barrel
275:
273:
269:plenum space
257:
242:
233:
211:
200:
195:
192:raise boring
188:
182:
177:
171:
167:
165:
138:
123:
116:
104:
100:South Africa
81:
77:
60:
57:Shaft mining
56:
55:
1213:Prospecting
1095:Sub-surface
983:(1): 90–92.
964:(1): 51–54.
880:, Edition 3
776:. Tampere,
727:Raise borer
538:ventilation
531:diesel fuel
390:shaft forms
113:Mine shafts
1233:Categories
1123:Directions
1041:techniques
759:References
722:Man engine
488:guide rope
460:shaft sets
424:rock bolts
386:rock bolts
348:false edge
75:projects.
18:Mine shaft
1203:Automated
1198:Abandoned
1114:Soft rock
1109:Hard rock
1061:Quarrying
923:3 October
888:North Bay
717:Headframe
657:Full Sink
503:mine cage
432:pneumatic
404:cast iron
396:Shotcrete
357:mineshaft
353:hoistroom
324:headframe
245:headframe
178:sub-shaft
146:Materials
126:plan view
1173:Longwall
1150:Borehole
1145:Bell pit
1076:Dredging
1056:Open-pit
826:10 April
700:See also
621:blasting
617:fly rock
613:Pre-Sink
543:brattice
507:elevator
442:liners.
287:ore body
234:Warszawa
134:concrete
1178:Retreat
1160:Stoping
1102:Classes
1048:Surface
778:Finland
682:bedrock
637:winches
619:during
496:truckle
472:buntons
440:polymer
428:bolting
412:bitumen
136:lined.
119:tunnels
92:Germany
84:sinkers
1071:Placer
1039:Mining
894:
821:GENUKI
799:
468:guides
416:halite
253:sheave
183:raises
143:People
130:timber
88:Canada
73:mining
1191:Other
1140:Shaft
1135:Slope
1130:Drift
1066:Strip
919:, BBC
884:Tempe
849:: 42.
514:skips
464:steel
400:brick
343:sheer
339:wheel
335:cable
330:hoist
249:hoist
176:or a
173:winze
168:shaft
96:China
925:2013
892:ISBN
828:2017
797:ISBN
694:muck
307:sump
302:ramp
267:, a
98:and
605:or
529:or
518:ore
157:ore
59:or
1235::
979:.
960:.
941:.
915:,
882:.
845:.
819:.
533:.
402:,
278:.
198:.
102:.
94:,
90:,
1031:e
1024:t
1017:v
981:1
962:1
900:.
886:/
830:.
805:.
623:.
185:.
34:.
20:)
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