AU2023202192A1 - Underground raise ladderway and installation method - Google Patents

Abstract

Provided is an underground raise ladderway section comprising a pair of ladder rails, each ladder rail defining a series of spaced rung apertures and sheet slots along a length thereof; a plurality of rungs operatively receivable in corresponding rung apertures of each ladder rail to form a ladder; at least one interlocking member configured to mount said pair of ladder rails to a surface; and a resiliently flexible and substantially flat sheet defining castellated edges on opposite sides thereof, each castellated edge operatively receivable in the series of sheet apertures of a ladder rail to form a protective surface around the ladder. CD 3/7 c'J NJJ

Description

CD 3/7

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NJJ UNDERGROUND RAISE LADDERWAY AND INSTALLATION METHOD TECHNICAL FIELD

[0001] This invention broadly relates to the field of

underground mining and more specifically to an underground

raise ladderway and an associated underground ladderway

installation method.

BACKGROUND ART

[0002] The following discussion of the background art is

intended to facilitate an understanding of the present

invention only. The discussion is not an acknowledgement or

admission that any of the material referred to is or was part

of the common general knowledge as at the priority date of the

application.

[0003] In underground mining, a raise generally refers to

a vertical or inclined excavation that leads from one level,

or drift, to another. A raise may also extend to the surface.

Raises may serve a number of purposes, including transportation

of ore and waste rock, ventilation, creating a free face for

mining, and/or movement of workers via ladders. For these

purposes, raises with diameters ranging from less than 2 to 5

metres and lengths up to several hundred metres are often

drilled by powerful raise-boring machines in underground

mines. Airleg drills may be used to create a square raise.

[0004] In many instances, such underground mining raises

serve as emergency escape routes via which miners can escape

to the surface in the event of an emergency. Accordingly, it

is common for raises to include a ladderway to permit miners to climb up out of the mine. Conventional ladderways are typically in the form of a prefabricated steel ladder surrounded with a steel mesh caging to provide a measure of protection from debris and from falling for the miners as they ascend the ladder inside the cage. Such metal ladderways for raises have been used for many decades in the field of mining.

[0005] Subsequent modern developments on conventional

ladderways for mining raises have primarily involved the use

of polymer materials to reduce metal corrosion and degradation

due to many mining environments being saline, wet or damp,

often leading to rust and corrosion of metal ladderways. For

example, subsequent developments have seen the use of elongate

plastic tubes with a separate interior ladder mounted via

mounting means, as described in AU2005312343 to Bortana Pty

Ltd, as well as a progression to a laddertube comprising an

elongate tube of plastics material with steps moulded directly

into the laddertube, as described in AU2014225271 to Hiram

(WA) Pty Ltd.

[0006] While a shift from metal ladderways to polymer-based

ladderways saw general improvement in the field regarding

corrosion resistance, it also introduced shortcomings in the

art. Specifically, prior art polymer tube ladderways, whilst

being resistant to corrosion, are bulky to transport and

cumbersome to install. Such logistics of transport and handling

of bulky polymer laddertube sections can increase both

transport and installation costs, and also increase

installation time and effort. Shipping of bulky and cumbersome

polymer laddertube sections also present challenges,

specifically to remote locations where mines are often located.

Additionally, introducing fastening apertures into polymer

tubes for installation purposes typically introduce potential points of failure which may exacerbate ingress of fluid and mechanical failures.

[0007] The current invention was conceived with these

shortcomings in mind.

SUMMARY OF THE INVENTION

[0008] According to a first aspect of the invention there

is provided an underground raise ladderway section comprising:

a pair of ladder rails, each ladder rail defining a series

of spaced rung apertures and sheet slots along a length

thereof;

a plurality of rungs operatively receivable in

corresponding rung apertures of each ladder rail to form a

ladder;

at least one interlocking member configured to mount said

pair of ladder rails to a surface; and

a resiliently flexible and substantially flat sheet

defining castellated edges on opposite sides thereof, each

castellated edge operatively receivable in the series of sheet

apertures of a ladder rail to form a protective surface around

the ladder.

[0009] The skilled addressee is to appreciate that the

ladder rails, rungs, interlocking member(s) and sheet are

easily flat-packed for transport purposes. Similarly, these

components are easily assembled on site to construct an

underground raise ladderway.

[0010] In an embodiment, each ladder rail defines a bracket

for receiving the interlocking member.

[0011] Typically, each ladder rail defines a bracket at an

upper and lower end thereof to facilitate mounting of the

ladder at both end of the ladder rails.

[0012] In an embodiment, each ladder rail defines the series

of rung apertures towards one side thereof with the sheet slots

defined toward another side thereof, both series of apertures

and slots defined along a length of the rail and spaced apart.

[0013] In an embodiment, the interlocking member includes

a cable attachment for receiving a cable to facilitate in

lowering a ladderway section into a raise.

[0014] In an embodiment, the interlocking member defines

mounting apertures via which the ladder rails are mountable to

a surface, such as an inside surface of a raise, by means of

suitable fasteners.

[0015] In an embodiment, one or each ladder rail includes

a spacing member at a lower or upper portion thereof, said

spacing member configured to abut against a ladder rail and/or

rung of a preceding or succeeding ladderway section when such

sections are arranged on top or below each other.

[0016] Typically, the a resiliently flexible and

substantially flat sheet comprises a polymer material.

[0017] In an embodiment, the resiliently flexible polymer

sheet comprises a high density polyethylene (HDPE) material.

[0018] In an embodiment, the resiliently flexible polymer

sheet is between 1mm and 10mm in thickness.

[0019] In an embodiment, the resiliently flexible polymer

sheet is a quadrilateral.

[0020] In an embodiment, the resiliently flexible polymer

sheet is a trapezoid.

[0021] In an embodiment, the resiliently flexible polymer

sheet comprises a curved trapezoid or isosceles trapezoid.

[0022] In an embodiment, the resiliently flexible sheet is

urged so that said opposite castellated sides each engages a

respective ladder rail so that the sheet forms a curved

protective surface.

[0023] In an embodiment, one non-castellated side of the

resiliently flexible polymer sheet defines an overlap portion

which is configured to overlap with another sheet of a

successive ladderway section.

[0024] According to a second aspect of the invention there

is provided an underground raise ladderway comprising a

plurality of underground raise ladderway sections in

accordance with the first aspect of the invention arranged on

top of each other.

[0025] According to a third aspect of the invention there

is provided an underground ladderway installation method

comprising the steps of:

providing a plurality of underground raise ladderway

sections in accordance with the first aspect of the invention;

lowering said ladderway sections into a raise; and

fastening each section to an inside surface of the raise

via the respective interlocking members so that the resiliently flexible polymer sheets of successive sections overlap to form a protective ladderway along the raise.

[0026] According to a further aspect of the invention there

is provided an underground raise ladderway section, an

underground raise ladderway and an associated underground

ladderway installation method, substantially as herein

described and/or illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

The description will be made with reference to the accompanying

drawings in which:

Figure 1 is a diagrammatic exploded-view representation

of parts of an underground raise ladderway section, in

accordance with aspects of the invention;

Figure 2 is a diagrammatic perspective-view

representation of assembled ladder rails, rungs and an

interlocking member of the underground raise ladderway section

of Figure 1;

Figure 3 is diagrammatic top-view representation of a

resiliently flexible polymer sheet of an underground raise

ladderway section;

Figure 4 is a diagrammatic exploded-view representation

of an underground raise ladderway section, in accordance with

aspects of the invention;

Figure 5 is a diagrammatic perspective-view

representation of the underground raise ladderway section of

Figure 4;

Figure 6 is a further diagrammatic perspective-view

representation of the underground raise ladderway section of

Figure 4;

Figure 7 is a diagrammatic perspective-view

representation of an underground ladderway comprised of a

plurality of the underground raise ladderway sections of Figure

4; and

Figure 8 is a diagrammatic side-view representation of

the ladderway of Figure 7.

DETAILED DESCRIPTION OF EMBODIMENTS

[0027] Further features of the present invention are more

fully described in the following description of several non

limiting embodiments thereof. This description is included

solely for the purposes of exemplifying the present invention

to the skilled addressee. It should not be understood as a

restriction on the broad summary, disclosure or description of

the invention as set out above.

[0028] In the figures, incorporated to illustrate features

of the example embodiment or embodiments, like reference

numerals are used to identify like parts throughout.

Additionally, features, mechanisms and aspects well-known and

understood in the art will not be described in detail, as such

features, mechanisms and aspects will be within the

understanding of the skilled addressee.

[0029] With reference now to the accompanying figures,

there is broadly shown one embodiment of an underground raise

ladderway section 10. Ladderway section 10 generally comprises

a pair of ladder rails 12, rungs 18, at least one interlocking

member 20, and a resiliently flexible and substantially flat

sheet 22. The skilled addressee is to appreciate that the

ladder rails 12, rungs 18, interlocking member(s) 20 and flat

sheet 22 are generally easily flat-packed for transport and/or

storage purposes. Similarly, these components are easily

assembled on site to construct a sturdy underground raise

ladderway 36, as described below.

[0030] As more clearly shown in Figures 1 and 2, each ladder

rail 12 generally defines a series of spaced rung apertures 14

and sheet slots 16 along a length thereof. In a typical

embodiment, each ladder rail 12 defines the series of rung

apertures 14 toward one side thereof with the sheet slots 16

defined toward another side thereof, both series of apertures

and slots 14 and 16 defined along a length of the rail 12 and

spaced apart, as shown. Ladderway section 10 also includes a

plurality of rungs 18 that are operatively receivable in

corresponding rung apertures of each ladder rail 12 to form a

ladder.

[0031] Each ladder rail 12 also defines a bracket 28 for

receiving the interlocking member 20. Typically, each ladder

rail 12 defines a bracket 28 at an upper and lower end thereof,

as exemplified, to facilitate mounting of the ladder formed in

this manner at both upper and lower ends of the ladder rails

12.

[0032] In one embodiment, one or each ladder rail 12 also

includes a spacing member 34 at a lower or upper portion

thereof, the spacing member 34 configured to abut against a

ladder rail 12 and/or rung 18 of a preceding or succeeding

ladderway section 10 when such sections 10 are arranged on top

or below each other, as shown in Figures 7 and 8. Spacing

members 34 generally facilitate proper installation of each

section 10 on top of each other, as will be appreciated by the

skilled addressee.

[0033] The at least one interlocking member 20 is configured

to mount the pair of ladder rails 12 to a surface, such as an

inside surface of a raise. In an embodiment, the interlocking

member 20 defines mounting apertures via which the ladder rails

12 are mountable to a surface, such as an inside surface of a

raise, by means of suitable fasteners, e.g. bolts, etc. In an

embodiment, the interlocking member 20 includes a cable

attachment 30 for receiving a cable 32 to facilitate in

lowering a ladderway section 10 into a raise during

installation.

[0034] The interlocking member 20 may be configured to

attach to the ladder rails 12 in a variety of manners. For

example, in the exemplified embodiment, the respective

brackets 28 and interlocking member defines interlocking

apertures and tabs with suitable detents and/or fasteners for

locking such tabs within the apertures to secure the ladder

rails 12 to the interlocking members 20, as shown. Of course,

variations hereon are possible and expected.

[0035] Ladderway section 10 also includes the resiliently

flexible and substantially flat sheet 22 which defines

castellated edges 24 on opposite sides 26 thereof, as shown.

The skilled addressee is to appreciate that the castellations

may take any of a variety of shapes and such various

castellations are included within the scope of the present

invention, e.g. squared castellations, curved castellations,

triangular castellations, etc.

[0036] Importantly, each castellated edge 24 is operatively

and complementarily receivable in the series of sheet slots 16

of a ladder rail 12 to form a protective surface around the

ladder formed in the manner described. In a typical embodiment,

the resiliently flexible sheet 22 is urged during installation

so that said opposite castellated sides 24 each engages a

respective ladder rail 12 so that the sheet 22 forms a curved

protective surface around the ladder.

[0037] In a preferred embodiment, the castellations form an

interference-fit with the respective sheet slots 16 whereby

the sheet 22 is locked to the rails 12, thereby obviating the

need for mechanical fasteners that may jeopardise a structural

integrity of the sheet 22. In an optional embodiment, each or

some castellations may also define apertures 24.1 via which

suitable detents or fasteners are passable in order to secure

the sheet to the ladder rails 12. However, such apertures 24.1

are generally constrained to each castellation, rather than an

overall surface of the sheet 22.

[0038] Importantly, by the resiliently flexible and

substantially flat sheet 22 defining suitable castellations

(with or without apertures 24.1) allows such castellated edge

24 to be operatively and complementarily receivable in the

series of sheet slots 16 of ladder rail 12 without requiring

apertures through a major surface of the sheet 22 for

fastening. For example, using rivets or similar fasteners to fasten a polymer sheet introduces potential points of failure into the major surface of the sheet, via which cracks may propagate and diminish an integrity of said sheet, e.g. ingress or water, mechanical failure, etc. By having the castellations, even with apertures 24.1 in such castellations only, means no such possible points of failure and mechanical weakness are introduced into the major surface of the sheet, which is often under mechanical stress due to being bent or bowed to form the protective surface around the ladder. Should an aperture 24.1 cause cracking, such mechanical failure is limited to that particular castellation rather than jeopardising the entire sheet.

[0039] Sheet 22 is typically made of a polymer material,

such as a high-density polyethylene (HDPE) material, or the

like. However, variations hereon are possible, including

metals, or the like. In an embodiment, one non-castellated

side of the resiliently flexible polymer sheet 22 defines an

overlap portion 38 which is configured to overlap with another

sheet 22 of a successive ladderway section, as shown in Figures

7 and 8. Such overlap portions 38 find particular application

in allowing water to run down an outside surface of the

ladderway 36 without entering into said ladderway 36.

[0040] In an embodiment, the resiliently flexible polymer

sheet is between 1mm and 10mm in thickness. The overlap portion

38 may be formed by the sheet being somewhat conical once the

castellated edges 24 are secured to the ladder rails 12, as

described above. To facilitate this, the resiliently flexible

polymer sheet 22 is a quadrilateral, such as a trapezoid,

particularly, a curved trapezoid or isosceles trapezoid which

provides a somewhat conical shape once engaged by the ladder

rails 12 to facilitate overlap to minimise water ingress.

[0041] In this manner, an underground raise ladderway 36

can be constructed by arranging a plurality of underground

raise ladderway sections 10 on top of each other, according to

requirements.

[0042] The present invention also includes a broad

underground ladderway installation method which typically

comprises the steps of providing a plurality of underground

raise ladderway sections 10, lowering said ladderway sections

into a raise, such as via cable 32, and fastening each

section 10 to an inside surface of the raise via the respective

interlocking members 20 so that the resiliently flexible

polymer sheets 22 of successive sections overlap to form a

protective ladderway 36 along the raise.

[0043] Applicant believes it particularly advantageous that

the present invention provides for underground raise ladderway

sections 10 which are easily flat-packed for transport

purposes. Sections 10 can further be easily assembled on site,

as required, in order to construct a ladderway 36 inside a

raise. Additionally, polymer sheets are typically receivable

in the series of sheet slots 16 of the ladder rail 12 via an

interference-fit, so that an overall surface integrity of the

sheet is not jeopardised via fastening apertures, facilitating

longevity of a resulting underground raise ladderway.

[0044] Optional embodiments of the present invention may

also be said to broadly consist in the parts, elements and

features referred to or indicated herein, individually or

collectively, in any or all combinations of two or more of the

parts, elements or features, and wherein specific integers are

mentioned herein which have known equivalents in the art to which the invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. In the example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail, as such will be readily understood by the skilled addressee.

[0045] The use of the terms "a", "an", "said", "the", and/or

similar referents in the context of describing various

embodiments (especially in the context of the claimed subject

matter) are to be construed to cover both the singular and the

plural, unless otherwise indicated herein or clearly

contradicted by context. The terms "comprising, " "having,

" "including, " and "containing" are to be construed as open

ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. As used herein, the term "and/or"

includes any and all combinations of one or more of the

associated listed items. No language in the specification

should be construed as indicating any non-claimed subject

matter as essential to the practice of the claimed subject

matter.

[0046] Spatially relative terms, such as "inner," "outer,"

"beneath, " "below, " "lower, " "above, " "upper, " and the like,

may be used herein for ease of description to describe one

element or feature's relationship to another element(s) or

feature(s) as illustrated in the figures. Spatially relative

terms may be intended to encompass different orientations of

the device in use or operation in addition to the orientation

depicted in the figures. For example, if the device in the

figures is turned over, elements described as "below" or

"beneath" other elements or features would then be oriented "above" the other elements or features. Thus, the example term

"below" can encompass both an orientation of above and below.

The device may be otherwise oriented (rotated 90 degrees or at

other orientations) and the spatially relative descriptors

used herein interpreted accordingly.

[0047] It is to be appreciated that reference to "one

example" or "an example" of the invention, or similar exemplary

language (e.g., "such as") herein, is not made in an exclusive

sense. Various substantially and specifically practical and

useful exemplary embodiments of the claimed subject matter are

described herein, textually and/or graphically, for carrying

out the claimed subject matter.

[0048] Accordingly, one example may exemplify certain

aspects of the invention, whilst other aspects are exemplified

in a different example. These examples are intended to assist

the skilled person in performing the invention and are not

intended to limit the overall scope of the invention in any

way unless the context clearly indicates otherwise. Variations

(e.g. modifications and/or enhancements) of one or more

embodiments described herein might become apparent to those of

ordinary skill in the art upon reading this application. The

inventor(s) expects skilled artisans to employ such variations

as appropriate, and the inventor(s) intends for the claimed

subject matter to be practiced other than as specifically

described herein.

[0049] Any method steps, processes, and operations

described herein are not to be construed as necessarily

requiring their performance in the particular order discussed

or illustrated, unless specifically identified as an order of

performance. It is also to be understood that additional or

alternative steps may be employed.

Claims (17)

1. An underground raise ladderway section comprising:

a pair of ladder rails, each ladder rail defining a series of

spaced rung apertures and sheet slots along a length thereof;

a plurality of rungs operatively receivable in

corresponding rung apertures of each ladder rail to form a

ladder;

at least one interlocking member configured to mount said

pair of ladder rails to a surface; and

a resiliently flexible and substantially flat sheet

defining castellated edges on opposite sides thereof, each

castellated edge operatively receivable in the series of sheet

apertures of a ladder rail to form a protective surface around

the ladder.

2. The underground raise ladderway section of claim 1,

wherein each ladder rail defines a bracket for receiving the

interlocking member.

3. The underground raise ladderway section of either of

claims 1 or 2, wherein each ladder rail defines a bracket at

an upper and lower end thereof to facilitate mounting of the

ladder at both end of the ladder rails.

4. The underground raise ladderway section of any of claims

1 to 3, wherein each ladder rail defines the series of rung

apertures towards one side thereof with the sheet slots defined

toward another side thereof, both series of apertures and slots

defined along a length of the rail and spaced apart.

5. The underground raise ladderway section of any of claims

1 to 4, wherein the interlocking member includes a cable attachment for receiving a cable to facilitate in lowering a ladderway section into a raise.

6. The underground raise ladderway section of any of claims

1 to 5, wherein the interlocking member defines mounting

apertures via which the ladder rails are mountable to a

surface, such as an inside surface of a raise, by means of

suitable fasteners.

7. The underground raise ladderway section of any of claims

1 to 6, wherein one or each ladder rail includes a spacing

member at a lower or upper portion thereof, said spacing member

configured to abut against a ladder rail and/or rung of a

preceding or succeeding ladderway section when such sections

are arranged on top or below each other.

8. The underground raise ladderway section of any of claims

1 to 7, wherein the resiliently flexible and substantially

flat sheet comprises a polymer material.

9. The underground raise ladderway section of claim 8,

wherein the resiliently flexible polymer sheet comprises a

high-density polyethylene (HDPE) material.

10. The underground raise ladderway section of either of

claims 8 or 9, wherein the resiliently flexible polymer sheet

is between 1mm and 10mm in thickness.

11. The underground raise ladderway section of any of claims

8 to 10, wherein the resiliently flexible polymer sheet is a

quadrilateral.

12. The underground raise ladderway section of any of claims

8 to 11, wherein the resiliently flexible polymer sheet is a

trapezoid.

13. The underground raise ladderway section of any of claims

8 to 12, wherein the resiliently flexible polymer sheet

comprises a curved trapezoid or isosceles trapezoid.

14. The underground raise ladderway section of any of claims

1 to 13, wherein the resiliently flexible sheet is urged so

that said opposite castellated sides each engages a respective

ladder rail so that the sheet forms a curved protective

surface.

15. The underground raise ladderway section of any of claims

1 to 14, wherein one non-castellated side of the resiliently

flexible sheet defines an overlap portion which is configured

to overlap with another sheet of a successive ladderway

section.

16. An underground raise ladderway comprising a

plurality of underground raise ladderway sections, in

accordance with any of claims 1 to 15, arranged on top of each

other.

17. An underground ladderway installation method

comprising the steps of:

providing a plurality of underground raise ladderway

sections in accordance with any of claims 1 to 15;

lowering said ladderway sections into a raise; and

fastening each section to an inside surface of the raise

via the respective interlocking members so that the resiliently flexible polymer sheets of successive sections overlap to form a protective ladderway along the raise.