WO2004053294A1

WO2004053294A1 - Height adjustable support prop

Info

Publication number: WO2004053294A1
Application number: PCT/AU2003/001612
Authority: WO
Inventors: Steven Stanley Drew
Original assignee: Croesus Mining N.L.
Priority date: 2002-12-06
Filing date: 2003-12-04
Publication date: 2004-06-24
Also published as: AU2002953141A0

Abstract

A height adjustable support prop for providing vertical support between a footwall and a hangingwall of an underground mine working. The height adjustable support prop comprises a vertically disposed upper sleeve telescopically slidable relative to a vertically disposed lower sleeve. An upper end of the upper sleeve and a lower end of the lower sleeve are each encased with a capsular seal. The height adjustable support prop is also provided with a means to telescopically slide the upper sleeve relative to the lower sleeve and thereby adjust an effective height of the height adjustable support prop so that the capsular seals can be located adjacent to the footwall and the hangingwall. There is also provided a means to facilitate an ingress of grout into an internal void contained within the upper and lower sleeves and the capsular seals. In use, when the internal void is filled with grout, the capsular seals take on a contoured profile corresponding to the respective contiguous surfaces of the footwall and the hangingwall.

Description

TITLE

HEIGHT ADJUSTABLE SUPPORT PROP FIELD OF THE INVENTION

The present invention relates to a height adjustable support prop, in particular to a height adjustable support prop for use in underground mines between the floor and ceiling of an underground mine working.

BACKGROUND OF THE INVENTION It is frequently necessary to provide a plurality of support props between the floor and ceiling of underground mine workings to allow miners to operate safely underground. Typically wooden pillars, cut to an appropriate size on site from wooden logs, are wedged between the floor (also known as a footwall) and a ceiling (also known as a hanging wall) of the underground mine workings. The wooden pillars may be provided with resilient caps to account for uneven surfaces on the floor and/or ceiling. Blasting in the vicinity of wooden pillars will dislodge or break them. Alternatively, a support prop may be formed from a bag placed inside a circular mesh ring about 1.5 metres high, whereupon the bag is filled with grout. Both methods of providing support props are time consuming and expensive. Furthermore, in sites where a hanging wall or footwall is contoured, it is often difficult to provided stable support therebetween with the above described prior art support props. The present invention attempts to overcome at least in part some of the aforementioned disadvantages.

SUMMARY OF THE INVENTION In accordance with a first aspect of the present invention there is provided a height adjustable support prop for providing vertical support between a footwall and a hanging wall of an underground mine working, the height adjustable support prop comprising a vertically disposed upper sleeve telescopically slidable relative to a vertically disposed lower sleeve, an upper end of the upper sleeve and a lower end of the lower sleeve each being encased with respective capsular seals, a means to slide the upper sleeve relative to the lower sleeve and thereby adjust an effective height of the height adjustable support prop such that in use respective capsular seals are disposed adjacent the footwall and hanging wall, and a means to facilitate an ingress of grout into an internal void contained within the lower and upper sleeves and capsular seals, such that in use when the internal void is filled with grout, the capsular seals take on a contoured profile of respective contiguous surfaces of the footwall and the hanging wall, thereby affording a rigid substantially vertical support prop having a height and respective surface contours that substantially matches a height and surface contours of the footwall and the hangingwall that the height adjustable support prop spans.

DETAILED DESCRIPTION OF THE DRAWINGS The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a diagrammatic view of a height adjustable support prop in accordance with the present invention in a retracted configuration located between a footwall and a hanging wall of an underground mine working;

Figure 2 is a diagrammatic view of the height adjustable support prop shown in Figure 1 in an extended configuration located between the footwall and the hanging wall of the underground mine working, wherein the height adjustable support prop is also shown attached to a grout delivery hose for delivery of grout to an interior void contained therein and a height adjusting means to adjust the height of the support prop;

Figure 3 is a diagrammatic view of the height adjustable support prop shown in

Figures 1 and 2 in an extended configuration located between the footwall and the hanging wall of the underground mine working, wherein the grout delivery hose and the height adjusting means have been removed from the height adjustable support prop; and

Figure 4 is a diagrammatic view of the height adjustable support prop in an extended configuration located between a contoured footwall and a contoured hanging wall, wherein the height adjustable support prop is shown attached to a grout delivery means via the grout delivery hose shown in Figure 2.

DESCRIPTION OF AN EMBODIMENT OF THE INVENTION Referring to the Figures, wherein like numerals and symbols refer to like parts throughout, there is shown a height adjustable support prop 10. The height adjustable support prop 10 includes a vertically disposed rigid lower sleeve 20 provided with a capsular seal 22 encasing a lower end 23 of the lower sleeve 20, and a vertically disposed rigid upper sleeve 30 provided with a capsular seal 32 encasing an upper end 33 of the upper sleeve 30, wherein the upper sleeve 30 is telescopically slidable relative to the lower sleeve 20. In this particular embodiment, the upper sleeve 30 is telescopically slidable within the lower sleeve 20. Typically, an O-ring sealing member 64 is provided between the lower and upper sleeves 20, 30, to seal a gap between adjacent respective vertical walls of the lower and upper sleeves 20, 30. Preferably, the sleeves 20, 30 are formed from a plastics material, such as polyvinyl chloride (PNC), or polyethylene (HDPE) having a diameter from about 30 mm to

2500 mm.

The capsular seals 22, 32 are secured about external surfaces of the lower and upper ends 23, 33, respectively, of the lower and upper sleeves 20, 30 by at least one corresponding securing band 24, 34.

Telescopic movement of the upper sleeve 30 with respect to the lower sleeve 20 is facilitated by a height adjustment means comprising a pneumatic or hydraulic ram 60 that is arranged in use to interconnect the lower and upper sleeves 20, 30 by engaging respective ends 61, 63 of the ram 60 with an upwardly disposed L-shaped bracket 28 outwardly extending from an external surface of the lower sleeve 20 and a downwardly disposed L-shaped bracket 38 outwardly extending from an external surface of the upper sleeve 30, as shown in Figures 1 and 2. Extension or contraction of the ram 60 is actuated by operation of a control valve 62. Extension of the ram 60 facilitates the upper sleeve 30 to telescopically slide upwardly relative to the lower sleeve 20 and thus extend the effective height of the height adjustable support prop

10, whilst contraction of the ram 60 consequently facilitates the upper sleeve 30 to telescopically slide downwardly relative to the lower sleeve 20 and thus shorten the effective height of the height adjustable support prop 10.

It is envisaged that the effective height of the height adjustable support prop 10 can be varied from about 1000 - 3000 mm.

It will also be understood that an additional height adjustment means could be required for height adjustment of support props 10 of the present invention with diameters and heights towards the higher end of the aforementioned ranges. The lower sleeve 20 is also provided with a grout inlet valve 21 located adjacent the lower capsular seal 22 to facilitate an ingress of grout, from a grout delivery means 68 via a grout delivery hose 69 as shown in Figure 4, into an internal void 66 contained within the support prop 10 when the upper sleeve 30 is either partially or fully extended. The upper sleeve 20 is also provided with an air outlet valve 31 located adjacent the upper capsular seal 32 to facilitate an egress of air out of the internal void 66 contained within the support prop 10 as grout is delivered into the void through the grout inlet valve 21.

The lower and upper sleeves 20, 30 are provided with respective lower and upper cylindrical mesh inserts 26, 36 that are also telescopically slidable with respect to one another. The purpose of the mesh inserts 26, 36 is to provide additional internal structural support for the height adjustable support prop 10 of the present invention. In use, a desired location for the height adjustable support prop 10 is chosen and the lower sleeve 20 of the support prop 10 is installed on the site such that the lower capsular seal 22 is adjacent to and contiguous with a surface of a footwall 40. The ram 60 is then engaged with the lower and upper L-shaped brackets 28, 38 and the ram 60 is actuated by the control valve 62 to extend to a degree whereupon the upper sleeve 30 slides telescopically with respect to the lower sleeve 20 until the upper capsular seal 32 is adjacent to a surface of a hanging wall 50. Clearly, the degree to which the ram 60 will be required to extend depends on substantially matching the effective height of the support prop 10 and the distance between the footwall 40 and the hanging wall 50. At this point, a locking mechanism provided between the lower and upper sleeves 20, 30 is tightened to secure the location of the upper sleeve 30 relative to the lower sleeve 20. The grout delivery hose 69 is then attached to the grout inlet valve 21 and grout is pumped into the internal void 66 contained within the lower and upper sleeves 20, 30 from the grout delivery means 68 via the grout delivery hose 69, as shown in Figure 4. Air is able to bleed from the internal void 66 through the air outlet valve 31 as the internal void 66 fills with grout. As the internal void 66 fills with grout and the mesh inserts 26, 36 are encased with grout, the lower and upper capsular seals 22, 32 also begin to fill with grout and to take up the contours of the adjacent footwall 40 and hanging wall 50, respectively. In this way, the contoured shaping of the lower and upper capsular seals 22, 32 enables each end of the support prop 10 to exactly conform to both profiles of the footwall 40 and the hanging wall 50, as shown in Figure 4, thus permanently wedging the support prop 10 in a static position. After the lower and upper capsular seals 22, 32 have filled to capacity with grout, the grout hose 69 is removed and the grout inlet valve 21 is permanently capped. The grout is then allowed to cure, typically about 72 hours before firing or work in the local area takes place.

In this way, the height adjustable support prop 10 of the present invention affords a strong, rigid substantially vertical pillar of a precise height and surface contour between the footwall 40 and the hanging wall 50 of an underground mine working. The height adjustable support prop 10 of the present invention is particularly applicable for use in areas where a pillar of rock bearing ore has been retained as a support prop in mine workings. The height adjustable support prop 10 may be readily employed to allow the pillar to be mined more economically.

Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention. For example, it will be understood that the lower sleeves 20of the height adjustable support prop 10 may be formed to be recoverable once the grout within the internal void has cured. The lower sleeves 20 may be formed from a pair of semi-cylindrical portions that can be bolted together. The bolts can be removed after the grout has set, the semi-cylindrical portions removed, then bolted back together again in order to be re-used in formation of a subsequent height adjustable support prop 10.

Claims

1. A height adjustable support prop for providing vertical support between a footwall and a hanging wall of an underground mine working, the height adjustable support prop comprising a vertically disposed upper sleeve telescopically slidable relative to a vertically disposed lower sleeve, an upper end of the upper sleeve and a lower end of the lower sleeve each being encased with respective capsular seals, a means to telescopically slide the upper sleeve relative to the lower sleeve and thereby adjust an effective height of the height adjustable support prop such that in use respective capsular seals are disposed adjacent the footwall and hangingwall, and a means to facilitate an ingress of grout into an internal void contained within the lower and upper sleeves and capsular seals, such that in use when the internal void is filled with grout the capsular seals take on a contoured profile of respective contiguous surfaces of the footwall and the hangingwall, thereby affording a rigid substantially vertical support prop having a height and respective surface contours that substantially match a height and respective surface contours of the footwall and the hangingwall that the height adjustable support prop spans.

2. The height adjustable support prop according to claim 1, characterised in that an O-ring sealing member is provided between the lower and upper sleeves to seal a gap between adjacent respective vertical walls of the lower and upper sleeves.

3. The height adjustable support prop according to claim 1 or claim 2, characterised in that the lower and upper sleeves are formed from a plastics material.

4. The height adjustable support prop according to any one of the preceding claims, characterised in that the capsular seals are secured about external surfaces of the lower and upper ends, respectively of the lower and upper sleeves by at least one securing band.

5. The height adjustable support prop according to any one of the preceding claims, characterised in that the means to telescopically slide the upper sleeve relative to the lower sleeve comprises a pneumatic or hydraulic ram that is arranged in use to interconnect the lower and upper sleeves by engaging respective ends of the ram with an upwardly disposed L-shaped bracket outwardly extending from an external surface of the lower sleeve and a downwardly disposed L-shaped bracket outwardly extending from an external surface of the upper sleeve.

6. The height adjustable support prop according to any one of the preceding claims, characterised in that the lower sleeve is provided with a grout inlet valve located adjacent the lower capsular seal, to facilitate an ingress of grout, from a grout delivery means via a grout delivery hose, into the internal void contained within the support prop.

7. The height adjustable support prop according to claim 6, characterised in that the upper sleeve is provided with an air outlet valve located adjacent the upper capsular seal to facilitate an egress of air out of the internal void contained within the support prop as grout is delivered into the internal void through the grout inlet valve.

8. The height adjustable support prop according to any one of the preceding claims, characterised in that the lower and upper sleeves are provided with respective lower and upper cylindrical mesh inserts that are telescopically slidable with respect to one another.

9. The height adjustable support prop according to any one of the preceding claims, characterised in that the lower and upper sleeves have a diameter from about 30 mm to 2500 mm.

10. The height adjustable support prop according to any one of the preceding claims, characterised in that a locking mechanism is provided between the lower and upper sleeves, whereby actuation of the locking mechanism secures the location of the upper sleeve relative to the lower sleeve.

11. The height adjustable support prop according to any one of the preceding claims, characterised in that the effective height of the height adjustable support prop can be varied from about 1000 mm to 3000 mm.

12. The height adjustable support prop according to any one of the preceding claims, characterised in that the upper and lower sleeves are removable after the grout in the internal void has cured such that the upper and lower sleeves can be reused in formation of a subsequent height adjustable support prop.