This is a nonprovisional patent application of U.S. Provisional Patent Application No. 61/647,695, filed May 16, 2012, and titled LAUNCH PLATFORM FOR HIGH WALL MINING, which is incorporated herein by reference.
The present invention relates to mining equipment, and more specifically to a launch platform for a high wall miner and conveyor cars and a method of high wall mining.
In high wall mining, for example of a coal seam in a mountain, a notch is cut in the side of the mountain at the elevation of the coal seam. This forms a flat surface, known as a bench, to work from and move equipment on, and a wall or face along which mine entries, also called shafts or rooms, are made into and along the coal seam. On the bench, a launch platform, also referred to as a table or deck, is used to push a continuous mining machine, also called a miner, forward against the high wall formed by the notch, cutting a mine entry horizontally into the coal seam.
As the miner is moved deeper in the coal seam, a coal conveyor car (for example, with a continuous web, belt, auger, or other conveyance to take away coal) is added behind the mining machine, and then behind each subsequent car, forming a mining string providing a continuous conveyor to remove coal as the miner cuts deeper into the wall. More specifically, generally a pair of cylinders, for example, hydraulic cylinders, can push each side of the miner and the subsequent conveyor cars connected in a string behind the miner. Often the maximum depth of the horizontal mine entry into the coal seam is limited by the length of the string formed by the cars behind the miner that can be effectively pushed by the hydraulic cylinders on the launch platform, for example, about 950 feet deep. Often the conveyor cars simply skid on the ground and thus significant friction and resulting resistance to advancement develops as more and more cars are added to the string behind the miner. Additionally, the maximum depth of the mine entry into the coal seam can be limited by the electrical current loss experienced in an excessively long power cable used to drive the mining head on the miner, for example, over about 800 feet of cable.
When the end of the coal seam or the maximum length of mining with the system used is reached, the conveyor cars are extracted one by one from the mine entry using the same launch platform and the same hydraulic cylinders. The extracted conveyor cars must be unhooked from the string, removed from the launch platform, and stowed. Such storage of conveyor cars on the narrow bench can be difficult when several dozen cars are used in a string.
After the miner is extracted, the launch platform is then moved sideways on the bench, along the face of the wall and next to the first mine entry just cut, to cut a target location for a second mine entry, with the second entry preferably extending parallel to the first entry. A pillar or supporting wall of coal is generally left between each pair of mine entries so that the mine entries do not collapse on the mining string under the weight of the overlying formation. However, because the launch platform hydraulic cylinders are used to advance the miner into the coal seam, for example, potentially pushing the miner from behind an 800 or 950 foot string of conveyor cars, it is difficult to ensure the side-by-side entries remain straight and parallel so that the pillars are not cut through into an adjacent entry. Such a cut through or too narrow of a pillar can result in subsidence of the overlying formation, trapping the miner and conveyor cars irretrievably.
Because of the height of a typical launch platform, in order for the miner to be advanced into the level of the coal seam, the bench must be downgraded below the level of the bottom of the coal seam, often by one or more feet. With a typical bench having a depth of 100 or more feet, this extra down downgrading removes a significant amount of material, material which must often be returned in order to again fill the bench and meet environmental and aesthetic requirements, thus greatly increasing the time and expense associated with the mining.
With the above described typical mining system and method, only one mine entry is being worked at any one time. Furthermore, during the extraction of the string after the maximum depth is reached in the coal seam, no coal is being cut or extracted because a second mine entry cannot be started until the entire extraction of cars and the miner is complete from the first mine entry, and the launch platform is moved to a new mine entry location adjacent the first mine entry.
The present invention may comprise one or more of the features recited in the attached claims, and/or one or more of the following features and combinations thereof.
An illustrative embodiment of a system and method for high wall bench mining, for example, of horizontal coal seams in mountains, includes a launch platform having two side-by-side tracks for guiding mining equipment, and utilizes two continuous miner machines and conveyor cars. With the presently disclosed system and method, two side-by-side mines entries can be worked simultaneously, one miner advancing deeper into the coal seam and conveyor cars being added behind the miner at a first mine entry, and the mining completed and cars and miner retreating and being extracted from the second mine entry. As conveyor cars are being extracted onto one track from the mine entry from which a string is retreating from, the cars are moved across the launch platform to the other track and are added behind the advancing miner machine launched from that track into the other adjacent mine entry.
An illustrative launch platform for high wall bench mining of two side-by-side mine entries into a coal seam, includes a support frame spanning the two side-by-side mine entries; a first track coupled to the support frame and having a first pair of guides configured for guiding a miner and conveyor cars; a second track coupled to the support frame and having a second pair of guides configured for guiding a miner and conveyor cars; the first and second tracks parallel to one another and spaced to provide a pillar between the two side-by-side mine entries; a first conveyor coupled to the support frame and positioned between the first pair of guides of the first track; and a second conveyor coupled to the support frame and positioned between the second pair of guides of the second track.
The illustrative launch platform can further include a first ramp associated with the first track, the ramp pivotably coupled to the support frame on an end positionable closest to the mine entries; and an adjustable height canopy mounted over at least a portion of the first ramp. The illustrative launch platform can further include a third track coupled to the support frame and having a third pair of guides configured for shifting and guiding a conveyor car between the first and second tracks.
An illustrative system of high wall mining of a coal seam using continuous mining machines and conveyor cars, includes a launch platform including a first and a second track, the first and second tracks parallel to one another; a first target for a first mine entry is aligned with the second track, a first mining machine is associated with the first mine entry; and a second target for a second mine entry aligned is with the first track, a second mining machine is associated with the second mine entry; and wherein the process of mining the first, second and a third mine entry in the coal seam includes the steps of: advancing the miner and subsequent cars from the second track into the first mine entry; retreating and removing cars from the first mine entry onto the second track simultaneous with advancing the miner and subsequent cars from the first track into the second mine entry, including the steps of: each car removed from the first mine entry is retracted onto the second track; each car retracted onto the first track is shifted to the first track; each car shifted to the first track is advanced into the second mine entry; upon completion of advancing into the second mine entry and extracting all cars from the first mine entry, the launch platform is slid along the face of the mine entries so that the first track is aligned with the first mine entry, the miner is extracted from the first mine entry onto the first track, then the launch platform is slid along the face of mine entries so that the first track is aligned with a third mine entry and the second track is aligned with the second mine entry, and the above process repeated to simultaneously retreat from the second mine entry and advance into the third mine entry.
An illustrative method of mining first, second, and third side-by-side mine entries into a coal seam, including the steps of positioning a launch platform with a side-by-side first and second track for conveyor cars so that the second track is aligned with the first mine entry and the first track is aligned with the second mine entry; advancing the miner and subsequent cars from the second track into the first mine entry; retreating and removing cars from the first mine entry onto the second track simultaneous with advancing the miner and subsequent cars from the first track into the second mine entry, including the steps of: each car removed from the first mine entry is retracted onto the second track; each car retracted onto the first track is shifted to the first track; each car shifted to the first track is advanced into the second mine entry; upon completion of advancing into the second mine entry and extracting all cars from the first mine entry, the launch platform is moved along the face of the mine entries so that the first track is aligned with the first mine entry, the miner is extracted from the first mine entry onto the first track, then the launch platform is moved along the face of mine entries so that the first track is aligned with a third mine entry and the second track is aligned with the second mine entry, and the above process repeated to simultaneously retreat from the second mine entry and advance into the third mine entry.
Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of the illustrative embodiments.
The detailed description particularly refers to the accompanying figures in which:
For the purposes of promoting and understanding the principals of the invention, reference will now be made to one or more illustrative embodiments illustrated in the drawings and specific language will be used to describe the same.
The launch platform 101 generally includes a support frame 110, a first track 130, a first conveyor 140, a first ramp 150, a second track 160, a second conveyor 170, a second ramp 180, and a cross track 190. Each of the first and second track 130 and 160 and their associated first and second ramps 150 and 180 provide for advancement and retraction of a mining equipment string 40 (
In the illustrative embodiment, only the second track 160 includes extraction cylinders 210 that are used to extract the mining equipment string 40 (
The cross track 190 provides for the shifting of conveyor cars 60 from the second track 160 to the first track 130. For example, as conveyor cars 60 are extracted from the mining equipment string 40 in the mine entry 20 (
Referring to
Referring to referring to
The slope of the ramps 150 and 180 is adjustable relative to the support frame 110 and the bench 12. Thus, the height at which the mining equipment string 42, including the miner 50, comes off of the ramp and into the mine entry 20 and 22 can be adjusted as desired based on the height of the bench 12 relative to the coal seam 14. For example, the floor 152 and 182 of the ramp 150 and 180 can be rotated about the pivot 154 and 184 by a pair of hydraulic cylinders 155 and 185 coupled between the base 152 and 182 and vertical posts 122 that are coupled to the support platform 110 and selectively driven by the hydraulic power supply 124.
Referring to
Each track 130 and 160 includes a pair of guides 132 and 162 that are configured for guiding a miner 50 and conveyor cars 60 by receiving and guiding wheels or another portion of the structure of the miner 50 and conveyor cars 60, keeping the miner and cars laterally aligned with the mine entry 20 and 22, and facilitating keeping the entries 20 and 22 parallel along their full depth. The guides 132 and 162 are also aligned with guides 153 and 183 on the ramps 150 and 180. In the illustrated embodiments, each respective pair of guides 132 and 162 are spaced about 42 inches apart, and the spacing between the centerlines (not shown) of the tracks 130 and 160 is about 12 feet.
By providing for lateral guidance of the miner 50, the space between the mine entries 20 and 22, which is generally a pillar 26, is kept intact and of sufficient width along the full depth of the miner entries 20 and 22 into the coal seam 14 to prevent collapse of the mine entries 20 and 22 due to the weight of the overlying formations. For example, the guides 132 and 162 may provide a channel in which the wheels of the miner 50 and conveyor cars 60 are retained and guided. Alternatively, the guides 132 and 162 may provide rail on which or along which the wheels of the miner 50 and conveyor cars 60 are guided.
The spacing between the parallel sets of tracks 130 and 160 is determined by the width of the peg 119 portion of the support frame 110. For example, in the illustrative embodiment, the width is about 48 inches. Depending on the desired pillar 26 width in the coal seam 14, a wider or narrower peg 119 can be utilized. In one illustrative embodiment, the width of peg 119 is adjustable or pegs of varying width 119 are interchangeable in order to vary the spacing between the tracks 130 and 160, thus providing a selected pillar 26 width.
The launch platform 101 may also include a transfer system for moving and guiding conveyor cars 60 between the first and second tracks 130 and 170. For example, for moving an conveyor car 60 that has been extracted from the mine entry 20 and onto the second track 160, across the peg 119 and onto the first track 130, so that the conveyor car may be added to and advanced with the advancing mining equipment string 40 into the mine entry 22. For example, the transfer system can include a third track, cross track 190, that is also coupled to the support frame 110 and includes a pair of guides 192.
The guides 192 may provide a channel in which a set of transverse wheels 62 of the conveyor cars 60 are retained and guided. Alternatively, the guides 192 may provide a rail on which or along which the transverse wheels 62 of the conveyor cars 60 are guided. Where the guides 192 intersect with the guides 132 and 162, a T or X intersection 194 is formed as shown in
Winches 198, for example, hydraulic winches selectively actuated by the hydraulic power source 124, can be used to pull the car 60 transversely across the launch platform 101. Upon the car 60 being positioned over the first track 130 and the advance wheels 64 being aligned with the guides 132, the transverse wheels 62 can be actuated to swing upward and out of the way, allowing the car 60 to lower and the advance wheels 64 to engage with the rails 132, bearing the weight of the car 60.
In an alternative embodiment, the track guides 132 and 162 or the wheels 64 retract downward or upward respectively, allowing the car 60 to be transversely moved from track 160 to track 130. In an additional alternative embodiment, the guides 192 extend upwardly to lift the car 60 so that the advance wheels 64 are clear from the guides 132 and 162 so that the car 60 can be moved on guides 192 transversely from track 160 to track 130.
In yet another alternative embodiment of the launch platform 101 and car 60, rather than transverse wheels 62 included with car 60, a dolly 230 as shown in
Referring to
The conveyors 140 and 170 may be a beltline type conveyor of about 36 feet in length, and detachable from the support frame 110 for more convenient transport of the launch platform 101. The conveyors 140 and 170 extend from the wall end 104 of the launch platform 101 and continue past the rear end 102 opposite the wall 10. Advantageously, as the end of a conveyor car 60 is at any position along the length of the launch platform 101 as the car is being advanced in the mine entry 20 or 22, or as the car is being extracted from the mine entry 20 and coal is still being conveyed on the mining equipment string 40, the conveyor 60 extending across the depth of the launch platform 101 will ensure that the coal is collected and not wasted.
Referring to
Detachment of the conveyors 140 and 170, which can be, for example, about 36 feet long, provides for movement and repositioning of the launch platform between benches 12, including transport on vehicle highways. After detachment of the conveyors, and the ramps are folded upward or detached, for the illustrative embodiment, the depth of the platform along the length of the tracks 130 and 170, between ends 102 and 104 is about 16 feet, and the width is about 24 feet, which will allow permitting and movement on most public roads. In one illustrative embodiment, the support frame 110 divides so that the first track 130, conveyor 140, and ramp 150 can be separated from the second track 160, conveyor 170, and ramp 180. In such an embodiment, the support frame 110 includes alignment and coupling hardware to ensure the tracks 130 and 140 are parallel when the two halves of the support frame are coupled. Additionally, the support frame 110 may include such alignment and coupling hardware on both sides of each half for the tracks 130 and 160 so that one track, for example the first track 130 can be left in position, and the other track 160 uncoupled, moved to the opposite side, and recoupled.
Typical prior art launch platforms are about 40 feet in depth or longer, in order to accommodate typical miner length of about 36 feet. With these miners typically being loaded onto such prior art launch platforms from the rear end, opposite the mine wall 10, the required bench in the prior art is generally more than 90 feet in depth from wall 10. With the present launch platform 110, and using miners 50 and cars 60 about 20 feet in length, and miners cars loaded onto the launch platform from the side or from the rear end 102, a bench 12 of only about 40 feet is required, providing a significant advantage in how much material must be moved in forming and in restoring the bench.
The launch platform 101 can be constructed primarily of steel, however, other rigid materials are contemplated and can be selected by a person of ordinary skill in the art based on considerations such as strength, durability, weight, cost, and ease of construction and maintenance.
An illustrative method 300 of high wall mining of a coal seam using continuous mining machines and conveyor cars and the illustrative embodiment 101 is shown in schematic form in
Referring to
Referring to
Upon completion of extraction of all car 60 of the retreating mining equipment string 40 from the mine entry 20, and completion of the advancing mining equipment string 42 into the mine entry 22 such that the launch platform 101 tracks 130 and 160 are empty, as shown in
Referring to
Although the illustrative embodiments relate to high wall mining, the inventive concept can be used with or adapted as is known in the art to be used with other types of mining, including longwall, room & pillar, and surface mining.
While the invention has been illustrated and described in detail in the foregoing drawings and description, the same is to be considered as illustrative and not restrictive in character, it being understood that only illustrative embodiments thereof have been shown and described and that all changes and modifications that come within the spirit and scope of the invention as defined in the claims and summary are desired to be protected.
Number | Name | Date | Kind |
---|---|---|---|
2698169 | Fawkes | Dec 1954 | A |
3897976 | Gallis | Aug 1975 | A |
3918536 | Deeter et al. | Nov 1975 | A |
4118072 | Kelley et al. | Oct 1978 | A |
4150853 | McCoy | Apr 1979 | A |
4441761 | Fields et al. | Apr 1984 | A |
5161857 | Mayercheck et al. | Nov 1992 | A |
5273344 | Volkwein et al. | Dec 1993 | A |
5709433 | Christopher et al. | Jan 1998 | A |
5782539 | Peterson | Jul 1998 | A |
5810447 | Christopher et al. | Sep 1998 | A |
5879057 | Schwoebel et al. | Mar 1999 | A |
5967616 | Offutt et al. | Oct 1999 | A |
6652035 | Chisholm | Nov 2003 | B2 |
7594702 | Lowery | Sep 2009 | B2 |
20040245843 | Lowery | Dec 2004 | A1 |
20040245844 | Lowery | Dec 2004 | A1 |
20040245845 | Lowery | Dec 2004 | A1 |
20040251732 | Lowery | Dec 2004 | A1 |
20080120926 | Antoline et al. | May 2008 | A1 |
Number | Date | Country |
---|---|---|
662915 | Sep 1995 | AU |
671935 | Sep 1996 | AU |
9633600 | Oct 1996 | WO |
9748883 | Dec 1997 | WO |
2004110915 | Dec 2004 | WO |
2006075910 | Jul 2006 | WO |
Entry |
---|
Caterpillar Inc.; Highwall Mining System; 2011; pp. 1-8. |
ADDCAR; Highwall Mining System; Broad Bench Highwall System for Benches Over 90ft; retrieved Sep. 16, 2011 from <<http://www.addcarsystems.com/broad.html>>. |
Number | Date | Country | |
---|---|---|---|
20130307315 A1 | Nov 2013 | US |
Number | Date | Country | |
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61647695 | May 2012 | US |