GB2152101A

GB2152101A - Mine system

Info

Publication number: GB2152101A
Application number: GB08334690A
Authority: GB
Inventors: David Anthony Smith
Original assignee: Mining Supplies Minsup Pty Ltd
Current assignee: Mining Supplies Minsup Pty Ltd
Priority date: 1983-12-31
Filing date: 1983-12-31
Publication date: 1985-07-31
Also published as: GB8334690D0

Abstract

A mine system for extracting a pillar (4) of mineral defined between a pair of spaced apart roadways (1), comprising an armoured, scraper chain conveyor (10) extending along a face (9) of the pillar (4) from which mineral is to be extracted, a shearer type mining machine (23) provided with at least one spiral vane rotary cutting head (26) and mounted on and/or guided by the scraper chain conveyor (10) for reciprocal movement with respect thereto, a plurality of hydraulically powered, self-advancing mine roof supports (21) extending between the mine floor and mine roof and located side-by-side along the side (12) of the conveyor (10) remote from the face (9) and attached to the individual line pans (13) making up the conveyor (10) by one or more double-acting advancing rams, the scraper chain conveyor (10), beyond one end of the pillar (4) either being curved into or being adapted to discharge onto a further conveyor (29) extending along a roadway (1), in the direction of advance of the face (9), the roadway (1) extending transversely of a cross drive (2) towards which the face (9) is to be advanced, a plough device (30) located at the entrance to the cross drive (2) and adapted to plough mineral from the further conveyor (29) at the entrance to the cross drive (2), with a packing system (31) located in the cross drive (2) and adapted to pack the ploughed-off mineral into the cross drive (2) until the latter is filled, thus forming a roof supporting pack. <IMAGE>

Description

SPECIFICATION Mine system This invention relates to a mine system for the extraction of pillars of mineral such as coal.

Although in Europe the most commonly employed mining technique is the long'j%'all system, with powered supports extending along an advancing or retreating l'ace and with controlled caving effected behind the supports, in other parts of the world, systems known as "room and pillar" etc., are operated, whereby caving is not encouraged, but on the contrary pillars of coal e.g. 75 yards square, are left in place to effect roof support, with the mineral being extracted from around the pillars firstly by driving a plurality of spaced apart roadways (which are usually parallel) through the seam, which roadways are intersected by a plurality of spaced apart cross drives (which again are usually parallel and may extend orthogonally to the roadways).

This system avoids the use of hydraulically powered, self-advancing roof supports, and their attendant cost, maintenance, initial installation and eventual removal after the seam is worked out, with the roof above the roadways and cross drives being stabilized by rock bolts. Mineral winning is effected by what is known as a continuous mining machine, which is self-propelled and mounted either on crawler tracks or on ground engaging wheels, a gathering and elevating conveyor of which discharges the won mineral into shuttle cars. These are loaded at the machine and then driven along the roadways and cross-drives, and then driven to a bunker or a hopper mounted over the main belt conveyor for conveyance to the surface up a drift, or to the shaft bottom for skip winding.

Although known as "continuous" miners, the operation is to a large extent intermittent and the economics of the system depends upon the efficient use of shuttle cars.

Although it is not uncommon to leave these pillars permanently in place, modern practice is to attempt to extract the pillars, and this is also done by the continuous miner/shuttle car system. This method of pillar extraction is not without hazard to both the continuous mining machine and its operator during extraction of pillars, with the machine frequently becoming buried, but the machine in any event having a relatively low mineral winning output.

According to the present invention, there is provided a mine system for extracting a pillar of mineral defined between a pair of spaced apart roadways, comprising an armoured, scraper chain conveyor extending along a face of the pillar from which mineral is to be extracted, a shearer type mining machine provided with at least one spiral vane rotary cutting head and mounted on and/or guided by the scraper chain conveyor for reciprocal movemem with respect thereto, a plurality of h;;ydrauSicaily powered self-advancing mine roof suppers extending between the mine floor and mine rocT and located side-by-side along the side or he conveyor remote from the face and attached te the individuai line pans making up the conveyor by one or more double-acting advancing rams, the scraper clam conveyor, beyond one end of the pillar either being curved into or being adapted to discharge onto a further conveyor extending along 3 roadway, in the direction of advance of the face, th,,' roadway extending ,-ransversely of a cross drive towards which the fac' is to be advanced, a plough device located at the entrance to the cross drive and adapted to plough mineral from the further conveyor at the entrance to the cross drive, with a packing system located in the cross drive and adapted to pack the ploughed-off mineral into the cross drive until the latter is filled, thus forming a roof supporting pack.

It will be appreciated that the provision of powered supports gives complete protection from roof fal!s to both the mining machine and the machine operator, while the packing o the cross drive towards which the face is advancing provides a roof supporting facility in that cross drive, e.g. which may be 1 5-feet wide and which would otherwise be unstable.

It follows that when the entire pillar has been extracted and the machine reaches the packed cross drive, the packing system is removed, if it has not previously been removed, and the machine continues to be reciprocated to and fro with respect to its scraper chain conveyor, so that its conventional, spiral vane rotary cutting heads) simply loads the packed material from the cross-drive onto the scraper chain conveyor from whence it is conveyed into the downstream mine conveyor system, with the plough and packing system then dismantled and re-assembled at the next, or next empty, cross drive.Furthermore the use of a shearer type mining machine, which is not dependent upon shuttle car availability, wins mineral at a more regular rate than that consequent upon operating the shuttle car system, and hence advantageously provides a more even loading of the mine conveyor system. In addition, a shearer type mining machine is able to win mineral at a tonnage that is substantially in excess of a continuous mining machine. It follows that as the (first) cross drive is approached by the shearer type mininy machine and its associated equipment i.e.

the scraper chain conveyor and the self-advancing roof supports, packing can commence at the next, or next empty, cross drive.

The packing system may be of the slusher type or the pump(ed) type. In the former case, the plough device would plough mineral on to the mine floor, which in the latter system, the plough device would plough mineral into a hopper etc., associated with the pump pack ing system. In detail, the scraper chain conveyor may be of single strand or twin strand type. The twin strand type may have inboard or outboard chains, with a single strand type or twin inboard strand type, the conveyor can be of a curved type, e.g. incorporating a 90 curve at the end of the face, and extending for a short distance along the roadway, to overlie a further conveyor, e.g. a beam stage loader, which is a conventional item of equipment in which case while the plough device may be a belt plough.

After the first cross drive has been packed with won mineral, which may occur after only some 20% of the pillar has been extracted, ploughing off of the material at that roadway is halted, e.g. by raising the plough device.

with the material remaining on the further conveyor. In most circumstances, the remaining conveying and/or any bunkering system of the mine will be able to handle the output from the shearer type mining machine. However, if for some reason this is not the case, then the plough device and the packing system can be transported to the next cross drive(s), for that (or those) to be packed with won mineral and hence act as additional bunkering capacity. In any event, if the next cross drive has not previously been packed with mineral extracted from a previous pillar, then the packing system needs to be set up in that next cross-drive for packing with mineral won at the commencement of extraction of the next pillar. Normally, the roadways would be parallel to one another, as would the cross drives, with the latter at right angles to the roadways, so that the pillars would be rectangular.

The invention will now be described in greater detail by way of example, with reference to the accompanying drawing.

In the drawing are iliustrated two parallel roadways 1 of a plurality of such roadways.

The roadways 1 are intersected at 90 by a plurality of parallel cross drives 2, so that rectangular pillars 3, 4, 5, 6, 7, 8, of mineral e.g. coal, are defined between a pair of roadways 1 and a pair of cross drives 2.

The mine system in accordance with the invention is about to remove the pillar 4, commencing at a face 9 of the pillar, by an advancing shortwall technique, and for that purpose an armoured scraper chain conveyor 10 is located in the cross drive 2 adjacent the face 9, so that the conveyor 10 has a face side 11 and a goaf side 12.

The conveyor 10 is built up in the usual way from a plurality of individual line pans 1 3 of unit length e.g. 5ft, secured together endto-end, each pan 1 3 having a pair of spaced apart, sigma section sidewalls 14. The conveyor 10 is of the centre strand type, for it includes a 90 curve 1 5 leading to a head end 1 6 of the conveyor or housing a chaindriving sprocket barrel (not shown) powered by an electric motor 1 7. fluid coupling 1 8 and speed reduction gearbox 1 9. with a return sprocket barrel (not shown) housed at a tail end 20 of the conveyor 10.A plurality of hydraulically powered. self-advancing mine roof supports 21 are located side by side along the goaf side 1 2 of the conveyor 1 0.

and have cantilever roof engaging beams 22 extending over the conveyor 10 and into close proximity with the face 9. Seated on the sidewall 1 4 is a single ended. shearer type mining machine 23, having a power module 24 housing an electric motor (not shown) to power a haulage unit 25, whereby the machine 23 is reciprocable along the face 9 and also to power a pick-armed, spiral vane rotary cutting head 26 carried on a ranging arm 27 extending from a gearhead 28 of the machine 23. The head end 1 6 of the conveyor 10 is located in the roadway 1 and is elevated, so that it may discharge onto a belt conveyor 29 extending further along the roadway 1.In the vicinity of the next cross drive 2 is located a belt plough device 30. adapted to plough mineral from the belt 1 A packing system in the form of a slusher bucket/packer 31 is illustrated, which operates in the conventional manner, by being driven in reciprocating manner along its cross drive, to pack that cross drive progressively, beginning at its end remote from the belt plough 30, with mineral ploughed from the belt conveyor 29 and on to the floor of that cross drive, until that cross drive is filled with a roof supporting pack of mineral removed from the face 9. Thereafter.

the plough device 30 is removed so that the belt conveyor 29 beyond the packed cross drive 2 can convey mineral removed from the face 9 either to the remainder conveyor/bunkering system of the mine or alternatively to the next cross drive 2, where the plough device 30 is reassembled, and the slusher bucker/packer 31 reassembled, to form a roof supporting pack in the next cross drive. Alternatively or in addition, should the bunkering system of the mine be filled to capacity, then it is possible to remove the plough device 30 and slusher bucket/packer 31 to successive cross drives, for these to be filled- with mineral, to provide additional bunkering capacity.

When the mining machine 23 has removed the pillar 4 and reaches the packed cross drive 1, its rotary cutting head 26 progressively dismantles the pack, by loading the same onto the armoured conveyor 10, and thence onto the belt conveyor 29 for transportation out of the mine and/or into the mine bunkering system.

Claims

1. A mine system for extracting a pillar of mineral defined between a pair of spaced apart roadways, comprising an armoured, scraper chain conveyor extending along a face of the pillar from which mineral is to be extracted, a shearer type mining machine provided with at least one spiral vane rotary cutting head and mounted on and/or guided by the scraper chain conveyor for reciprocal movement with respect thereto, a plurality of hydraulically powered, self-advancing mine roof supports extending between the mine floor and mine roof and located side-by-side along the side of the conveyor remote from the face and attached to the individual line pans making up the conveyor by one or more double-acting advancing rams, the scraper chain conveyor, beyond one end of the pillar either being curved into or being adapted to discharge onto a further conveyor extending along a roadway, in the direction of advance of the face, the roadway extending transversely of a cross drive towards which the face is to be advanced, a plough device located at the entrance to the cross drive and adapted to plough mineral from the further conveyor at the entrance to the cross drive, with a packing system located in the cross drive and adapted to pack the ploughed-off mineral into the cross drive until the latter is filled, thus forming a roof supporting pack.

2. A mine system as claimed in Claim 1, wherein the packing system is of the slusher type.

3. A mine system as claimed in Claim 1, wherein the packing system is of the pumped type.

4. A mine system as claimed in any prededing claim wherein the scraper chain conveyor is of the single strand type.

5. A mine system as claimed in any one of Claims 1 to 3, wherein the scraper chain conveyor is of the twin strand type.

6. A mine system as claimed in Claim 5, wherein the twin strands are inboard.

7. A mine system as claimed in Claim 5, wherein the twin strands are outboard.

8. A mine system as claimed in any preceding claim, wherein the scraper chain conveyor is curved at 90 or so, at the end of the face, and into an adjacent roadway.

9. A mine system as claimed in Claim 8, wherein the armoured scraper chain conveyor extends a relatively short distance along the roadway to overlie a further conveyor.

10. A mine system as claimed in Claim 9, wherein the further conveyor is a belt conveyor.

11. A mine system as claimed in any one of claims 1 to 8 wherein the scraper chain conveyor discharges onto a beam stage loader conveyor, an elevated end of which discharges onto a belt conveyor.

12. A mine system as claimed in any preceding, wherein the plough device is a belt plough.

1 3. A mine system as claimed in any preceding claim, wherein, after the first cross drive has been packed with won mineral, ploughing off of the material at that roadway is halted, with the material remaining on the belt conveyor.

14. A mine system as claimed in Claim 13, wherein, the mineral remaining on the belt conveyor is conveyed to the remaining conveying and/or any bunkering system of the mine.

1 5. A mine system as claimed in Claim 13, wherein the plough device and the packing system is transported to the next cross drive(s) and the material remaining on the belt conveyor is ploughed and packed into that (or those) cross drives, which act as additional bunkering capacity.

16. A mine system as claimed in any preceding claim, wherein the roadways are parallel to one another.

17. A mine system as claimed in any preceding claim, wherein the cross drives are parallel to one another.

1 8. A mine system as claimed in any preceding claim, wherein, the cross drives are at right angles to the roadways.

1 9. A mine system for extracting a pillar of mineral defined between a pair of spaced apart roadways, substantially as hereinbefore described with reference to the accompanying drawing.