CA2040716C - Mine shaft sinking - Google Patents

Mine shaft sinking Download PDF

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Publication number
CA2040716C
CA2040716C CA002040716A CA2040716A CA2040716C CA 2040716 C CA2040716 C CA 2040716C CA 002040716 A CA002040716 A CA 002040716A CA 2040716 A CA2040716 A CA 2040716A CA 2040716 C CA2040716 C CA 2040716C
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Canada
Prior art keywords
stage
equipping
shaft
sinking
stages
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Expired - Lifetime
Application number
CA002040716A
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French (fr)
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CA2040716A1 (en
Inventor
Bruce Alexander Sobey
Malcolm Ernest Greenway
Helmut Teerman Bernadus Jozefus Dost
Sidney Gibson
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Anglo American Corp of South Africa Ltd
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Anglo American Corp of South Africa Ltd
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Filing date
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Priority claimed from GB909008669A external-priority patent/GB9008669D0/en
Application filed by Anglo American Corp of South Africa Ltd filed Critical Anglo American Corp of South Africa Ltd
Publication of CA2040716A1 publication Critical patent/CA2040716A1/en
Application granted granted Critical
Publication of CA2040716C publication Critical patent/CA2040716C/en
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Expired - Lifetime legal-status Critical Current

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  • Excavating Of Shafts Or Tunnels (AREA)
  • Earth Drilling (AREA)

Abstract

In a method of sinking a mine shaft, the shaft is excavated and lined from a sinking stage and the previously excavated and lined shaft is simultaneously equipped from an equipping stage which is located above the sinking stage and which follows the sinking stage down the shaft. In this way, considerable time savings can be achieved in the sinking of the shaft.

Description

BACKGROUND TO THE INVENTION
THIS invention relates to the sinking of mine shafts.
In a conventional mine shaft sinking operation, there are three distinct steps. Firstly, shaft excavation and lining is carried out. This is done from a sinking stage in the shaft and employs kibbles to raise broken rock from the bottom of the shaft as excavation proceeds. Rope winders and a headgear equipped with temporary sheaves at the surface are used to raise and lower the sinking stage and the kibbles.
Once the shaft is fully excavated and lined with concrete, the sinking stage is taken to the surface and dismantled or modified for equipping conditions.
Secondly, an equipping stage is assembled and lowered into the lined shaft at the surface using the previously installed sinking winders and headgear. The kibbles are replaced by equipping skeletons which are used to transport men and permanent equipment such as shaft steelwork, services and guides to the equipping stage, from which the shaft can be equipped. Once the shaft has been fully equipped with the permanent equipment, the equipping stage is dismantled and its components are raised to the surface.
Thirdly and finally, the permanent headgear sheaves and new ropes are installed and the new shaft is commissioned.
Clearly, the three step procedure is a time-consuming one.
SUMMARY OF THE INVENTION

According to the present invention there is provided a method of sinking a mine shaft, the method comprising the steps of excavating and lining the shaft from a sinking stage and, at substantially the same time, simultaneously equipping previously excavated and lined zones of the shaft from an equipping stage which is located above the sinking stage and which follows the sinking stage down the shaft.
The sinking and equipping stages can be moved independently of one another down the shaft as sinking proceeds. Preferably the stages are moved by respective sinking stage and equipping stage winders mounted on the stages themselves, on supporting steelwork spanning across the shaft, or at surface.
In one form of the invention, a permanent headgear and associated winding equipment is installed at surface at an early stage, excavated material from the shaft face is raised to the equipping stage in kibbles driven by kibble hoists, the material is transferred to shaft conveyances at the equipping stage, and the shaft conveyances, with the excavated material, are raised to surface using the permanent headgear and associated winding equipment.
In this case, the sinking and equipping stages may be moved independently of one another down the shaft as sinking proceeds by means of the permanent headgear and associated winding equipment. The kibbles may be loaded into kibble bridles at the equipping stage, and the kibble bridles are raised to surface using the permanent headgear and associated winding equipment. In another embodiment, material is emptied from the kibbles into skips at the equipping stage, and the skips are raised to surface using the permanent headgear and associated winding equipment.
In another embodiment of the invention, excavated material from the shaft face is raised to the equipping stage in kibbles which are transferred at the equipping stage to ropeless shaft conveyances, the ropeless conveyances then transporting the kibbles to the surface. In this case, the ropeless conveyances are driven by linear motor drive systems with the stators of,the linear motor drive systems installed in the shaft from the equipping stage and with the rotors of the linear motor drive systems being mounted on the ropeless conveyances.
Typically, the ropeless conveyances are moved paternoster fashion between the surface and an intermediate level above the equipping stage, and yo-yo fashion between the intermediate level and the equipping stage. A traversing apparatus is then provided at the intermediate level for transferring the ropeless conveyances between the paternoster above the intermediate level and the yo-yo paths below the intermediate level.
In both embodiments the sinking and equipping stages will be independently supported off the shaft, by means of releasable supports, at each successively lower position of the stages.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings which illustrate two embodiments of the shaft sinking method of the invention and in which:
Figure 1 is a cross-sectional view illustrating the first embodiment at shaft collar and pre-sink level;
Figure 2 is a cross-sectional view illustrating the first embodiment at the level of the equipping stage;

-S-Figure 3 is a cross-sectional view of the bottom end of the shaft illustrating the first embodiment at the level of the sinking stage and below; and Figure 4 is a cross-sectional view illustrating the second embodiment using ropeless conveyances.
SPECIFIC DESCRIPTION
Figures 1 to 3, which in combination illustrate a first embodiment of the invention, show various levels in a mine shaft 10 during the sinking thereof. As a first step in the shaft sinking process a shaft collar 12 and shaft pre-sink 14 are formed at the surface.
A sinking stage 28 is assembled in the pre-sink 14. At the same time, permanent headgear and winding equipment, indicated generally with the numeral 18, is erected at the surface. The permanent winding equipment includes a pair of skip winders 20 and a conveyance winder 22. Permanent sheaves 19 and 21 form part of the headgear and winding equipment 18.
The sinking stage 28 is used to carry out the initial excavation of the shaft beneath the shaft pre-sink 14. During this procedure, the sinking stage can be supported off suitable steelwork erected for the purpose at surface level, or directly off the permanent winding equipment. As soon as the shaft is deep enough, an equipping stage 30 is assembled in the shaft above the sinking stage 28. Supporting steelwork 16 is installed at the bottom of the pre-sink 14, spanning across the shaft.
The steelwork 16 supports a set of sheaves 24 and a set of sheaves 26.
The sinking and equipping stages 28 and 30 are unconnected, and may in fact be spaced apart by a substantial vertical distance. Nevertheless, as will appear from the description which follows, they may be considered to be grouped together in tandem in the sense that the equipping stage follows the sinking stage down the shaft as sinking proceeds.
The apparatus of Figures 1 to 3 includes a sinking stage winder 32 for winding ropes 34 passing around the sheaves 24 for the purposes of raising and lowering the sinking stage 28. In the illustrated embodiment, the stage winder 32 is mounted on the sinking stage itself. In other embodiments, the sinking stage winder could be surface mounted with suitable sheaves on the sinking stage. In this case the sheaves 24 would not be necessary.
The apparatus of Figures 1 to 3 also includes an equipping stage winder 36 for winding ropes 38 passing around the sheaves 26 for the purposes of raising and lowering the equipping stage. In the illustrated embodiment, the equipping stage winder is mounted on the equipping stage 30. As in the case of the sinking stage winder 32, the equipping stage winder could be mounted instead at surface level with suitable sheaves on the sinking stage. In this case the sheaves 26 on the steelwork 16 would not be necessary.
A still further possibility for the sinking and equipping stage winders is to mount them on the supporting steelwork 16, once again with suitable sheaves on the sinking and equipping stages themselves. With this configuration, there would again be no requirement for the sheaves 24 and 26 on the steelwork 16.
By independently operating the stage winders 32 and 36, irrespective of their positions, the sinking equipping stages can be raised and lowered in the shaft entirely independently of one another without any assistance from the surface mounted headgear and winding equipment. It is however within the scope of the _7_ invention for the sinking and equipping ~ stages to be raised and lowered when required using the permanent headgear and surface-mounted winding equipment.
Of course in the latter case there is no requirement for independent sinking and equipping stage winders.
The sinking and equipping stages each have a number of horizontal decks 42, 43.
From the decks 42, cleaning and concrete lining of the shaft is carried out.
Mounted beneath the lowest deck 42 of the sinking stage is lashing gear (not illustrated) which includes a conventional cactus grab that is used to lift broken rock, resulting from blasting operations at the shaft face 44, into kibbles 46.
The kibbles 46 are suspended on ropes 48 and are raised and lowered by a kibble hoist winder 50 mounted on a lower deck 43 of the equipping stage 30. The rope 48 passes over a jib arm 52 which is mounted on the top deck 43 of the equipping stage for pivotal movement about a vertical axis. After a round of blasting at the shaft face 44, a kibble 46A is lowered by the hoist winder 50 and jib arm 52 to the shaft face where it is loaded with broken rock using the lashing gear.
The invention is not limited to the use of lashing gear for loading the broken rock into the kibbles. A lazy chain system, or in fact any other suitable loading system, could equally well be used.
When the kibble is full of broken rock, it is raised to the top deck 43 of the equipping stage 30. The jib arm 52 is swivelled about the vertical axis to swing the full kibble into a kibble bridle 54 suspended on a rope 56 extending about the permanent sheaves 19 at the surface and controlled by the relevant skip winder 20.
Once loaded into the kibble bridle, the kibble is disconnected from the rope 48 and the bridle, with the kibble on board, is raised to surface by the relevant skip winder 20 for disposal of the broken rock. Another kibble can now be lowered to the _g_ bottom of the shaft to collect a fresh charge of broken rock.
During unloading of the contents of the kibble bridle 54, another similar bridle can be lowered down to the top deck 43 of the equipping stage using the other skip winder 20. With appropriate timing of the loading and unloading operations, rapid removal of the broken rock from the shaft bottom can take .place.
To enable the kibbles to pass through the equipping and sinking stages 28 and during travel to and from the shaft face, vertical kibble passages 60 and 62 are provided that extend through the decks 42 and 43. Between the sinking and equipping stages, rope guides incorporating tensioning pulleys 47 are provided to guide the kibbles 46 during their travel between the sinking and equipping stages.
For drilling and loading of broken rock, the sinking stage will be situated close to the shaft face 44. However, before each blast, the sinking stage must be raised away from the face 44, using the stage winder 32, to prevent damage to it.
After blasting the sinking stage can again be lowered to the correct elevation for drilling and lashing.
As stated previously, shaft cleaning and lining operations are carried out from the decks 42 of the sinking stage 28. While the shaft cleaning and lining operations are under way, permanent installation of shaft steelwork and shaft services, such as electrical cables, piping and so forth is carried out from the decks 43 of the equipping stage 30. The bottom deck of the equipping stage may be provided with sealing means to prevent potentially hazardous blast-generated fumes from passing up the shaft to the equipping stage.
The sinking and equipping stages are moved independently of one another by means of their own stage winding gear, with each successive movement of the stages taking place when the necessary work has been completed at each level. Thus the stages will not necessarily be moved at the same time to a lower location, but the general principle is that the equipping stage follows the sinking stage down the shaft, with shaft sinking and equipping operations being conducted on the two stages at substantially the same time.
At each progressively lower level as sinking proceeds, it is necessary to support the sinking and equipping stages and to reposition the ropes 34 and 38. In the illustrated embodiment, the supporting steelwork 16 is periodically dismantled and re-anchored at a lower elevation in the shaft. The stages themselves are supported at each new level by means of releasable supports 70 and 72 which are inserted into preformed pockets 74,76 in the wall of the shaft. The supports 70, 72 remain in operation at each level until such time as the sinking or equipping work is completed at that level, and they are then released to permit lowering of the respective stages to lower levels,. where they are again employed to anchor the stages in position.
As mentioned previously, the permanent equipping of the shaft is carried from the decks 43 of the equipping stage 30. Part of the permanent equipment is the shaft steelwork, including buntons, skip guides and so forth. The kibble bridles 54 are designed to run in the permanent skip guides that have already been installed from the equipping stage.
Men and materials are raised and lowered to the equipping and sinking stages in conveyances 78 carried by a rope 80 passing around the permanent sheave 21 and controlled by the conveyance winder 22.
Once the shaft has reached the full design depth, and has been fully equipped, the now defunct stages 28 and 30 are dismantled and their components are raised to surface using the permanent headgear equipment. The kibble bridles are replaced by permanent skips and the conveyances 78 by permanent personnel and material conveyances.
As an alternative to the use of kibble bridles to transport the full kibbles to the surface, it would also be possible to empty the full kibbles arriving at the top deck of the equipping stage into permanent skips which would then be wound up to the surface using the permanent headgear and winding equipment. In this case, suitable handling equipment would be provided at the top deck of the equipping stage to empty the full kibbles into the skips.
It is believed that a considerable time saving can be achieved in the sinking of a mine shaft in the manner described above, because the sinking and equipping functions are carried out at the same time and also because the final headgear and winding equipment is installed right at the outset.
Figure 4 illustrates a second embodiment of the invention which makes use of ropeless conveyances. The Figures shows a shaft which has been sunk to a depth below the first working level in the mine and which is equipped with ropeless conveyances 110 that move due to linear motor activity. The stators 111 of the linear motor drive system are fixed n the shaft and the rotors of the system are mounted on the conveyances 110.
Reference may be made to the specification of PCT/GB90/00335 for the details of a suitable linear motor drive system.
In Figure 4, the shaft face is marked with the numeral 112 and the surface collar level with the numeral 113. A mufti-platformed sinking stage 114 is supported off supporting steelwork 115 spanning across the shaft. A rope winder 127 is provided on the stage 114 to raise and lower the sinking stage as required during the drilling, blasting and lashing operations carried out from the stage 114.
The winder 127 acts on a rope 129 passing upwardly from the stage 114, around a sheave 131 mounted on the steelwork 115 and back to the stage 114.
An equipping stage, located above the sinking stage, is similarly supported off the steelwork 115 with a winder 132 provided on the stage 116 for the purposes of raising and lowering it as required. In this case, the winder 132 acts on a rope 134 passing upwardly from the stage 116, around a sheave 35 on the steelwork 115 and back to the stage 116.
As in the first embodiment, there are various alternative positions for the sinking stage winder 127 and the equipping stage winder 132 besides on the stages themselves. The winders could, for instance, be mounted on the steelwork 115 or at surface.
Also as in the first embodiment, it will be necessary to support the stages 114 and 116 as the shaft gets deeper and the stages move down. Once again, this is achieved by relocating the steelwork 115 at progressively lower anti lower levels, re-arranging the ropes 129 and 134, and by supporting the stages themselves at each new level with the use of releasable supports 150.
Kibbles 117 can pass from the shaft face 112 through the stages 114 and 116 to the top of the stage 116 where a crane 126, with the illustrated pivoting jib arm, is provided for loading the kibbles 117 onto and off the ropeless conveyances 110. In practice, the kibbles 117 are hoisted to the stage 116 by means of the crane using a kibble hoist winder 151 mounted on that stage. Rope guides are once again provided to guide the movement of the kibbles during their movement between the stages 114 and 116.
At an intermediate level 118 there is a traversing apparatus 124 for transferring conveyances 110 from one linear motor path to another. The traversing apparatus 124 may transfer conveyances 110 between the linear motor paths which extend upwardly to the surface from the level 118, between the linear motor paths extending downwardly to the stage 116 from the level 118, and between these upper and lower linear motor paths.
At the surface there is a conveyance storage zone 119. Above the zone 119 there is a surface loading level 121 where a crane 123 is provided to unload kibbles from the conveyances 110 as they arrive from underground and to replace them with empty kibbles 117.
Another traversing apparatus 125 operates to transfer the conveyances 110 from one linear motor path to the other, i.e. from the ascending linear motor path to the descending linear motor path, so that the conveyances 110 can return into the shaft.
Above the level 118 the conveyances 110 circulate paternoster fashion with some being removed and others being inserted at the zone 119 as circumstances dictate.
Below the level 118, each conveyance 110 that is diverted downwardly by the traversing apparatus 124 moves down to the top of the stage 116. Here, the crane 126 removes an empty kibble from the conveyance 110 and loads a full kibble, hoisted from the shaft face, in its place. The conveyance 110 now climbs back to the level 118 where it joins the paternoster for subsequent transfer to the surface. The loading and unloading of the conveyances 110 at the stage 116 can take place on either linear motor path, depending on the operation of the traversing apparatus 124.
It will be appreciated that conveyances 110 move yo-yo fashion between the level 118 and the stage 116 and circulate paternoster fashion above the level 118.
Full kibbles 117 are hoisted from the shaft face to the top of the equipping stage where the crane 126 loads them onto conveyances 110 which transport them to the surface. At the surface, the crane 123 removes the kibbles from the conveyances 110 for subsequent unloading of the kibble contents. Empty kibbles are loaded by the crane 123 onto empty conveyances 110 which travel down the paternoster to the level 118. At that level, the they are diverted by the traversing apparatus 124 to the stage 116, down one or other of the linear motor paths between the level 118 and the stage 116. On the stage 116, the empty kibbles are attached to the hoisting rope and are lowered to the shaft face to collect further loads of broken rock created by the excavation procedures.
The underlying principle of the second embodiment is the same as that of the first embodiment; in that the equipping stage follows the sinking stage down the shaft, with shaft sinking and equipping operations being carried out from the two stages at substantially the same time. As before, the stages can be moved independently of one another, and not necessarily at the same rate.
As in the first embodiment, equipping of the shaft takes place from the decks of the equipping stage 116 while excavation and lining is being carried out from the decks of the sinking stage 114. In this embodiment, the equipping procedures include the installation of the ropeless system, i.e. the stators 11, as excavation proceeds and the equipping stage moves to progressively lower and lower levels.
Once again, with equipping taking place at substantially the same time as shaft sinking and lining, it is anticipated that the completion time of the shaft can be reduced considerably compared to the conventional three-stage shaft sinking technique. With levels like the level 118 in use, development and actual mining can take place even before the shaft reaches its ultimate depth 140.

Claims (15)

1.
A method of sinking a mine shaft, the method comprising the steps of excavating and lining the shaft from a sinking stage and, at substantially the same time, equipping previously excavated and lined zones of the shaft from an equipping stage which is located above the sinking stage and which follows the sinking stage down the shaft.
2.
A method according to claim 1 wherein the sinking and equipping stages are moved independently of one another down the shaft as sinking proceeds.
3.
A method according to claim 2 wherein the sinking and equipping stages are moved respectively by sinking stage and equipping stage winders mounted on the stages themselves, on supporting steelwork spanning across the shaft, or at surface.
4.
A method according to claim 1 wherein a permanent headgear and associated winding equipment is installed at surface at an early stage, excavated material from the shaft face is raised to the equipping stage in kibbles driven by kibble hoists, the material is transferred to shaft conveyances at the equipping stage, and the shaft conveyances, with the excavated material, are raised to surface using the permanent headgear and associated winding equipment.
5.
A method according to claim 4 wherein the kibbles are loaded into kibble bridles at the equipping stage, and the kibble bridles are raised to surface using the permanent headgear and associated winding equipment.
6.
A method according to claim 4 wherein material is emptied from the kibbles into skips at the equipping stage, and the skips are raised to surface using the permanent headgear and associated winding equipment.
7.
A method according to claim 3 wherein excavated material from the shaft face is raised to the equipping stage in kibbles which are transferred at the equipping stage to ropeless shaft conveyances, the ropeless conveyances then transporting the kibbles to the surface.
8.
A method according to claim 7 wherein the ropeless conveyances are driven by linear motor drive systems and wherein the stators of the linear motor drive systems are installed in the shaft from the equipping stage with the rotors of the linear motor drive systems being mounted on the ropeless conveyances.
9.
A method according to claim 8 wherein the ropeless conveyances are moved paternoster fashion between the surface and an intermediate level above the equipping stage.
10.
A method according to claim 9 wherein the ropeless conveyances are moved yo-yo fashion between the intermediate level and the equipping stage, and wherein traversing apparatus is provided at the intermediate level for transferring the ropeless conveyances between the paternoster above the intermediate level and the yo-yo paths below the intermediate level.
11.
A method according to claim 4 wherein the kibbles are raised to the top of the equipping stage through vertical passages formed in the sinking and equip ding stages.
12.
A method according to claim 10 wherein the kibbles are raised to the top of the equipping stage through vertical passages formed in the sinking and equipping stages.
13.
A method according to claim 11 wherein the kibbles are guided between the sinking and equipping stages by means of rope guides extending between the stages.
14.
A method according to claim 12 wherein the kibbles are guided between the sinking and equipping stages by means of rope guides extending between the stages.
15.
A method according to claim 1 wherein the sinking and equipping stages are independently supported off the shaft, by means of releasable supports, at each successively lower position of the stages.
CA002040716A 1990-04-18 1991-04-17 Mine shaft sinking Expired - Lifetime CA2040716C (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB909008669A GB9008669D0 (en) 1990-04-18 1990-04-18 The sinking of mine shafts
ZA902920 1990-04-18
ZA90/2920 1990-04-18
GB9008669.5 1990-04-18

Publications (2)

Publication Number Publication Date
CA2040716A1 CA2040716A1 (en) 1991-10-19
CA2040716C true CA2040716C (en) 2003-10-21

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Application Number Title Priority Date Filing Date
CA002040716A Expired - Lifetime CA2040716C (en) 1990-04-18 1991-04-17 Mine shaft sinking

Country Status (4)

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AU (1) AU650010B2 (en)
BR (1) BR9101574A (en)
CA (1) CA2040716C (en)
ZW (1) ZW4591A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112627826B (en) * 2020-12-03 2022-05-03 招金矿业股份有限公司夏甸金矿 Safe and efficient shaft tunneling method
CN117386374B (en) * 2023-12-13 2024-03-08 中国建筑第五工程局有限公司 Shaft tunneling device with supporting structure

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Publication number Publication date
ZW4591A1 (en) 1992-04-22
BR9101574A (en) 1991-12-10
CA2040716A1 (en) 1991-10-19
AU7525391A (en) 1991-10-24
AU650010B2 (en) 1994-06-09

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