U.S. patent application number 15/571972 was filed with the patent office on 2018-05-24 for suspension and guidance apparatus for tools and platforms relative to a mill.
This patent application is currently assigned to RUSSELL MINERAL EQUIPMENT PTY LTD. The applicant listed for this patent is RUSSELL MINERAL EQUIPMENT PTY LTD. Invention is credited to Peter John Rubie.
Application Number | 20180141052 15/571972 |
Document ID | / |
Family ID | 57217337 |
Filed Date | 2018-05-24 |
United States Patent
Application |
20180141052 |
Kind Code |
A1 |
Rubie; Peter John |
May 24, 2018 |
Suspension and Guidance Apparatus for Tools and Platforms Relative
to A Mill
Abstract
The present disclosure provides an apparatus for suspending and
guiding at least one tool or work platform externally about a
grinding mill, the apparatus including (a) a fixed track suspended
above the grinding mill and extending about an outer periphery
thereof in a plane substantially parallel to a surrounding floor of
the mill, and, (b) at least one carriage assembly mounted to the
track for suspending and guiding the at least one tool or work
platform, the at least one carriage assembly configured to provide
the at least one tool or work platform with at least two degrees of
freedom, and wherein a first degree of freedom is linear movement
along a first axis orthogonal to the surrounding floor of the
mill.
Inventors: |
Rubie; Peter John;
(Toowoomba, Quensland, AU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
RUSSELL MINERAL EQUIPMENT PTY LTD |
Toowoomba, Queensland |
|
AU |
|
|
Assignee: |
RUSSELL MINERAL EQUIPMENT PTY
LTD
Toowoomba, Queensland
AU
|
Family ID: |
57217337 |
Appl. No.: |
15/571972 |
Filed: |
May 6, 2016 |
PCT Filed: |
May 6, 2016 |
PCT NO: |
PCT/AU2016/050333 |
371 Date: |
January 8, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B25J 11/008 20130101;
B02C 17/18 20130101; B02C 23/00 20130101 |
International
Class: |
B02C 17/18 20060101
B02C017/18; B25J 11/00 20060101 B25J011/00; B02C 23/00 20060101
B02C023/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 6, 2015 |
AU |
2015901622 |
Claims
1. An apparatus for suspending and guiding at least one tool
externally about a grinding mill, the apparatus including: (a) a
fixed track suspended above the grinding mill and extending about
an outer periphery thereof in a plane substantially parallel to a
surrounding floor of the mill; and, (b) at least one carriage
assembly mounted to the track for suspending and guiding the at
least one tool, the at least one carriage assembly configured to
provide the at least one tool with at least two degrees of freedom,
and wherein a first degree of freedom is linear movement along a
first axis orthogonal to the surrounding floor of the mill.
2. The apparatus according to claim 1, wherein a second degree of
freedom is linear movement along the track.
3. The apparatus according to claim 1, wherein five degrees of
freedom are provided, further including: (a) a third degree of
freedom being angular movement about the first axis; (b) a fourth
degree of freedom being angular movement about a second axis
orthogonal to the first axis; and, (c) a fifth degree of freedom
being linear movement about a third axis orthogonal to both the
first and second axes.
4. The apparatus according to claim 1, wherein the apparatus is
further configured to suspend and guide at least one platform and
to provide the at least one platform with at least two degrees of
freedom, and wherein a first degree of freedom provided to the at
least one platform is linear movement along an axis orthogonal to
the surrounding floor of the mill.
5. The apparatus according to claim 4, wherein the second degree of
freedom provided to the at least one platform is linear movement
along the track.
6. The apparatus according to claim 5, wherein four degrees of
freedom are provided to the at least one platform, further
including: (a) a third degree of freedom being angular movement
about the axis orthogonal to the surrounding floor of the mill;
and, (b) a fourth degree of freedom being linear movement parallel
to the surrounding floor of the mill.
7. The apparatus according to claim 1, wherein the carriage
assembly is a first carriage assembly that includes: (a) a first
carriage moveably mounted to the track for linear movement
therealong; (b) a first post member supported by the first carriage
and arranged to be orthogonal to the surrounding floor of the mill,
at least a part of the post member moveable along the first axis
orthogonal to the surrounding floor of the mill; and, (c) a first
tool carriage for carrying the at least one tool, the tool carriage
mounted to the post member such that the tool carriage is provided
with angular movement about the first axis and angular movement
about a second axis orthogonal to the first axis, the tool carriage
further including a linear slide mechanism allowing the at least
one tool to be slidably received thereby allowing the at least one
tool to move along a third axis orthogonal to both the first and
second axes.
8. The apparatus according to claim 4, wherein the apparatus
includes a second carriage assembly for supporting the at least one
platform, the second carriage assembly including: (a) a second
carriage moveably mounted to the track for linear movement
therealong; (b) a second post member supported by the secondary
carriage and arranged to be orthogonal to the surrounding floor of
the mill, at least a part of the post member moveable along an axis
orthogonal to the surrounding floor of the mill; and, wherein, the
at least one platform is mounted to a distal end of the second post
member to allow angular movement about the axis orthogonal to the
surrounding floor of the mill and linear movement orthogonal to the
second post member.
9. The apparatus according to claim 7, wherein the at least one
platform is supported by the first carriage assembly.
10. The apparatus according to claim 8, wherein the first carriage
assembly is moveably mounted to a first track and the second
carriage assembly is moveably mounted to a second track, the second
track parallel to the first track.
11. The apparatus according to claim 1, wherein the at least one
tool is a linerbolt removal tool.
12. The apparatus according to claim 1, wherein the at least one
platform is a work platform.
13. An apparatus for suspending and guiding at least one linerbolt
removal tool and at least one work platform externally about a
grinding mill, the apparatus including: (a) a fixed track suspended
above the grinding mill and extending about an outer periphery
thereof in a plane substantially parallel to a surrounding floor of
the mill; (b) a first carriage assembly coupled to the track for
supporting the at least one linerbolt removal tool, the first
carriage assembly configured to provide the at least one linerbolt
removal tool with at least two degrees of freedom, and wherein a
first degree of freedom is linear movement along an axis orthogonal
to the surrounding floor of the mill; and, (c) a second carriage
assembly coupled to the track for supporting the at least one work
platform, the second carriage assembly configured to provide the at
least one work platform with at least two degrees of freedom, and
wherein a first degree of freedom is linear movement along an axis
orthogonal to the surrounding floor of the mill.
14. The apparatus according to claim 13, wherein the at least one
linerbolt removal tool is provided with five degrees of freedom and
the at least one work platform is provided with four degrees of
freedom.
15. The apparatus according to claim 13, wherein a third carriage
assembly is provided for supporting a second linerbolt removal tool
externally about the grinding mill.
16. The apparatus according to claim 15, wherein a fourth carriage
assembly is provided for supporting a third linerbolt removal tool
externally about the grinding mill.
17. The apparatus according to claim 16, wherein a fifth carriage
assembly is provided for supporting a fourth linerbolt removal tool
externally about the grinding mill.
18. The apparatus according to claim 17, wherein a sixth carriage
assembly is provided for supporting a second work platform
externally about the grinding mill.
Description
PRIORITY DOCUMENTS
[0001] The present application claims priority from Australian
Provisional Patent Application No. 2015901622 titled "SUSPENSION
AND GUIDANCE APPARATUS FOR TOOLS AND PLATFORMS RELATIVE TO A MILL"
and filed on 6 May 2015, the contents of which are hereby
incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an apparatus for suspension
and guidance of tools and platforms relative to a mill, and in one
example to the suspension and guidance of linerbolt removal tools
and work platforms about the exterior of a grinding mill.
DESCRIPTION OF THE PRIOR ART
[0003] The reference in this specification to any prior publication
(or information derived from it), or to any matter which is known,
is not, and should not be taken as an acknowledgment or admission
or any form of suggestion that the prior publication (or
information derived from it) or known matter forms part of the
common general knowledge in the field of endeavour to which this
specification relates.
[0004] Sacrificial liners are secured to the internal casing of ore
grinding mills. They are typically provided as segments, and they
are secured internally of the mill shell by bolts which are fitted
from the internal side of the shell and project through apertures
in the liners and through mounting bores in the shell. A nut and
sealing washer are threaded onto and tightened onto each bolt from
outside the shell, drawing the liner to the inner surface of the
shell. An example of a conventional liner segment fastener system
is shown in U.S. Pat. No. 4,018,393. Typically the bolts used for
such application are referred to as linerbolts.
[0005] Ore mills are generally run continuously for economic
efficiency. The continuous process wears down the liners over a
period of time, which will depend on the type of ore and
application, after which the liners will have to be replaced.
Because down time of the ore mill adversely affects the economic
efficiency of the process, it is essential to change liners as
quickly as possible.
[0006] In such applications, the bolts on liners become corroded
and clearances between bolts and holes become compacted with ore
fines. This results in difficult bolt removal. As a result the many
bolts that are utilised to attach the liners to the mill shell are
often required to be freed manually by the use of large
sledge-hammers, and more frequently by percussive devices such as
jack-hammers and hydraulically powered hammers to provide
repetitive impacts.
[0007] Liner replacement involves removal of nuts, typically
followed by hammering the exposed bolt from the outside the mill.
In known hammering devices capable of delivering the necessary
impacts, a high reaction force is produced which necessitates that
such devices be carried by articulating machines or be rigidly
attached to some support structure. Various types of hydraulic and
pneumatic hammering devices, commonly referred as linerbolt removal
tools, are shown in International publication WO1997/026116, U.S.
Pat. No. 6,904,980 and U.S. Pat. No. 8,196,676.
[0008] Typically linerbolt removal tools are suspended from
monorails or telescoping jibs, which requires manual manipulation
and leads to error in tool alignment. Whilst efficiency has
improved over the years with use of linerbolt removal tools, it is
desirable to further improve the replacement of liners.
[0009] US 2007/0180678 and US 2012/0102703 propose a robotized
method of removing bolts from SAG and/or ball mills. A five-axis
anthropomorphic robot mounted on rails is used to address handling
and alignment issues. However, such an anthropomorphic robot is an
expensive option particularly when two or more robots are disposed
around the mill and is likely to require a complicated control
system.
[0010] Another method proposed in WO2014/124491 involves the
manipulation of tools about the exterior of a mill along a beam
which is broadly concentric to the cylindrical section of the mill
shell. However this apparatus only functions to its highest
potential on the cylindrical section of the mill shell. Furthermore
such a system does not aid workers faced with inevitable manual
tasks.
[0011] It is against this background, and the problems and
difficulties associated therewith, that the present invention has
been developed.
SUMMARY OF THE PRESENT INVENTION
[0012] In one broad form the present invention seeks to provide an
apparatus for suspending and guiding at least one tool externally
about a grinding mill, the apparatus including: [0013] a) a fixed
track suspended above the grinding mill and extending about an
outer periphery thereof in a plane substantially parallel to a
surrounding floor of the mill; and, [0014] b) at least one first
carriage assembly mounted to the track for suspending and guiding
the at least one tool, the at least one carriage assembly
configured to provide the at least one tool with at least two
degrees of freedom, and wherein a first degree of freedom is linear
movement along a first axis orthogonal to the surrounding floor of
the mill.
[0015] Typically, a second degree of freedom is linear movement
along the track.
[0016] Typically, five degrees of freedom are provided, further
including: [0017] a) a third degree of freedom being angular
movement about the first axis; [0018] b) a fourth degree of freedom
being angular movement about a second axis orthogonal to the first
axis; and, [0019] c) a fifth degree of freedom being linear
movement about a third axis orthogonal to both the first and second
axes.
[0020] Typically, the apparatus is further configured to suspend
and guide at least one platform and to provide the at least one
platform with at least two degrees of freedom, and wherein a first
degree of freedom provided to the at least one platform is linear
movement along an axis orthogonal to the surrounding floor of the
mill.
[0021] Typically, the second degree of freedom provided to the at
least one platform is linear movement along the track.
[0022] Typically, four degrees of freedom are provided to the at
least one platform, further including: [0023] a) a third degree of
freedom being angular movement about the axis orthogonal to the
surrounding floor of the mill; and, [0024] b) a fourth degree of
freedom being linear movement parallel to the surrounding floor of
the mill.
[0025] Typically, the carriage assembly is a first carriage
assembly that includes: [0026] a) a first carriage moveably mounted
to the track for linear movement therealong; [0027] b) a first post
member supported by the first carriage and arranged to be
orthogonal to the surrounding floor of the mill, at least a part of
the post member moveable along the first axis orthogonal to the
surrounding floor of the mill; and, [0028] c) a first tool carriage
for carrying the at least one tool, the tool carriage mounted to
the post member such that the tool carriage is provided with
angular movement about the first axis and angular movement about a
second axis orthogonal to the first axis, the tool carriage further
including a linear slide mechanism allowing the at least one tool
to be slidably received thereby allowing the at least one tool to
move along a third axis orthogonal to both the first and second
axes.
[0029] Typically, the apparatus includes a second carriage assembly
for supporting the at least one platform, the second carriage
assembly including: [0030] a) a second carriage moveably mounted to
the track for linear movement therealong; [0031] b) a second post
member supported by the secondary carriage and arranged to be
orthogonal to the surrounding floor of the mill, at least a part of
the post member moveable along an axis orthogonal to the
surrounding floor of the mill; and, wherein, the at least one
platform is mounted to a distal end of the second post member to
allow angular movement about the axis orthogonal to the surrounding
floor of the mill and linear movement orthogonal to the second post
member.
[0032] Typically, the at least one platform is supported by the
first carriage assembly.
[0033] Typically, the first carriage assembly is moveably mounted
to a first track and the second carriage assembly is moveably
mounted to a second track, the second track parallel to the first
track.
[0034] Typically, the at least one tool is a linerbolt removal
tool.
[0035] Typically, the at least one platform is a work platform.
[0036] According to another broad form the present invention seeks
to provide an apparatus for suspending and guiding at least one
linerbolt removal tool and at least one work platform externally
about a grinding mill, the apparatus including: [0037] a) a fixed
track suspended above the grinding mill and extending about an
outer periphery thereof in a plane substantially parallel to a
surrounding floor of the mill; [0038] b) a first carriage assembly
coupled to the track for supporting the at least one linerbolt
removal tool, the first carriage assembly configured to provide the
at least one linerbolt removal tool with at least two degrees of
freedom, and wherein a first degree of freedom is linear movement
along an axis orthogonal to the surrounding floor of the mill; and,
[0039] c) a second carriage assembly coupled to the track for
supporting the at least one work platform, the second carriage
assembly configured to provide the at least one work platform with
at least two degrees of freedom, and wherein a first degree of
freedom is linear movement along an axis orthogonal to the
surrounding floor of the mill.
[0040] Typically, the at least one linerbolt removal tool is
provided with five degrees of freedom and the at least one work
platform is provided with four degrees of freedom.
[0041] Typically, a third carriage assembly is provided for
supporting a second linerbolt removal tool externally about the
grinding mill.
[0042] Typically, a fourth carriage assembly is provided for
supporting a third linerbolt removal tool externally about the
grinding mill.
[0043] Typically, a fifth carriage assembly is provided for
supporting a fourth linerbolt removal tool externally about the
grinding mill.
[0044] Typically, a sixth carriage assembly is provided for
supporting a second work platform externally about the grinding
mill.
[0045] According to another broad form the present invention seeks
to provide an apparatus for suspending and guiding at least one
tool externally about a grinding mill via a fixed track, said
apparatus provides five degrees of freedom to said at least one
tool, wherein at least one of said degrees of freedom is linear
movement along a first axis orthogonal to the surrounding floor of
said mill.
[0046] Typically, a second of said five degrees of freedom is
angular movement about said first axis orthogonal to the
surrounding floor of said mill.
[0047] Typically, a third of said five degrees of freedom is
angular movement about a second axis orthogonal to said first axis,
and a fourth of said five degrees of freedom is linear movement
along an axis orthogonal to said second axis of rotation.
[0048] Typically, a fifth degree of freedom is movement along a
fixed track parallel to and located above said mill and said mill
floor.
[0049] Typically, the apparatus also provides four or less degrees
of freedom to said at least one platform, wherein at least one of
said degrees of freedom is linear movement along a first axis
orthogonal to the surrounding floor of said mill.
[0050] Typically, a second of said four degrees of freedom is
angular movement about said first axis orthogonal to the
surrounding floor of said mill.
[0051] Typically, a third of said four degrees of freedom is linear
movement along an axis parallel to the surrounding floor of said
mill.
[0052] Typically, a fourth degree of freedom is movement along a
fixed track parallel to and located above said mill and said mill
floor.
[0053] Typically, at least one tool is a first tool and said
apparatus comprises a fixed track parallel to the outline of said
mill in plan view, such that said fixed track is disposed outside
and surrounding said mill, a primary carriage is mounted for travel
along said fixed track, and a substantially straight first rail
orthogonal to said surrounding floor of said mill is mounted to
said primary carriage, and at least one tool carriage is mounted
for first angular movement about said first axis orthogonal to said
floor and second angular movement about a second axis orthogonal to
said first axis, said first tool mounted to said tool carriage via
a linear slide mechanism allowing said first tool to move along an
axis orthogonal to said second axis.
[0054] Typically, at least one platform is mounted to a secondary
carriage mounted for travel along said fixed track, and a
substantially straight second rail orthogonal to said surrounding
floor of said mill is mounted to said secondary carriage, and at
least one platform is mounted for angular movement about said first
axis of said second rail and linear movement orthogonal to said
first axis of said second rail.
[0055] Typically, said fixed track is a structure suspended above
said mill.
[0056] Typically, said first tool is a linerbolt removal tool.
[0057] Typically, said platform is a work platform.
[0058] According to another broad form the present invention seeks
to provide an apparatus for suspending and guiding at least a
linerbolt removal tool and at least a work platform externally of a
grinding mill, said linerbolt removal tool associated with a first
carriage assembly and used for knocking out linerbolts and liners
on a cylindrical main body portion of said mill and knocking out
linerbolts on a frusto-conical end portion of said mill connected
to said cylindrical main body portion, said first carriage assembly
providing no more than five degrees of freedom to its linerbolt
removal tool and wherein at least one of said degrees of freedom is
linear movement along an axis orthogonal to the surrounding floor
of said mill. Said work platform with a second carriage assembly
and used for manual tasks on a cylindrical main body portion of
said mill and manual tasks on a frusto-conical end portion of said
mill connected to said cylindrical main body portion, said second
carriage assembly providing no more than four degrees of freedom to
its first work platform and wherein at least one of said degrees of
freedom is linear movement along an axis orthogonal to the
surrounding floor of said mill.
[0059] Typically, a second linerbolt removal tool associated with a
third carriage and similar to that of the primary carriage
assembly, said second linerbolt removal tool and its associated
carriage assembly used for knocking out linerbolts on a cylindrical
main body portion of said mill and knocking out linerbolts on a
frusto-conical end portion of said mill connected to said
cylindrical main body portion.
[0060] Typically, a third linerbolt removal tool associated with a
fourth carriage and similar to that of the primary carriage
assembly, said third linerbolt removal tool and its associated
carriage assembly used for knocking out linerbolts on a cylindrical
main body portion of said mill and knocking out linerbolts on a
frusto-conical end portion of said mill connected to said
cylindrical main body portion.
[0061] Typically, a fourth linerbolt removal tool associated with a
fifth carriage and similar to that of the primary carriage
assembly, said fourth linerbolt removal tool and its associated
carriage assembly used for knocking out linerbolts on a cylindrical
main body portion of said mill and knocking out linerbolts on a
frusto-conical end portion of said mill connected to said
cylindrical main body portion.
[0062] Typically, a second work platform associated with a sixth
carriage and similar to that of the secondary carriage assembly,
said second work platform and its associated carriage assembly used
for manual tasks on a cylindrical main body portion of said mill
and manual tasks on a frusto-conical end portion of said mill
connected to said cylindrical main body portion.
[0063] It will be appreciated that the broad forms of the invention
and their respective features can be used in conjunction,
interchangeably and/or independently, and reference to separate
broad forms in not intended to be limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] An non-limiting example of the present invention will now be
described with reference to the accompanying drawings, in which:
--
[0065] FIG. 1A is a perspective view of an example of an apparatus
for suspending and guiding at least one tool or work platform
externally about a grinding mill;
[0066] FIG. 1B is a plan view of the apparatus of FIG. 1A;
[0067] FIG. 1C is an end view of the apparatus of FIG. 1A;
[0068] FIG. 2A is a perspective view of a further example of an
apparatus for suspending and guiding at least one tool or work
platform externally about a grinding mill;
[0069] FIG. 2B is a plan view of the apparatus of FIG. 2A;
[0070] FIG. 2C is an end view of the apparatus of FIG. 2A;
[0071] FIG. 3 is an enlarged perspective view of an example of a
first carriage assembly mounted to a track for suspending and
guiding a linerbolt removal tool;
[0072] FIG. 4 is an enlarged perspective view of an example of a
second carriage assembly mounted to a track for suspending and
guiding a work platform; and,
[0073] FIG. 5 is an enlarged perspective view of an example of a
work platform and linerbolt removal tool mounted to the same
carriage assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0074] An example of an apparatus 1 for suspending and guiding at
least one tool 30 externally about a grinding mill 11 will now be
described with reference to FIGS. 1A to 1C.
[0075] In this example, a fixed track 20 is suspended above the
grinding mill 11 so as to extend about an outer periphery thereof
in a plane substantially parallel to a surrounding floor of the
mill 11.
[0076] At least one first carriage assembly 18 is mounted to the
track for suspending and guiding the at least one tool 30, the at
least one first carriage assembly 18 configured to provide the at
least one tool 30 with at least two degrees of freedom including a
first degree of freedom that is linear movement along a first axis
orthogonal to the surrounding floor of the mill.
[0077] The above described arrangement provides a number of
advantages.
[0078] Firstly, the at least one tool is able to access a large
area of the mill casing so that required maintenance actions (for
example linerbolt removal during liner replacement) can be
performed more efficiently requiring less mill rotations and time
out of service. This may provide the mill operator with a
significant cost saving.
[0079] The apparatus further provides safety benefits to mill
workers involved in routine mill maintenance. In the past, tools
were suspended from hanging cables that were free to move about
which presents a safety risk to workers who may be struck with the
tools. In the above described arrangement, the tool is suspended
and guided by a carriage assembly mounted to a track which provides
a stable and secure means of supporting the tool.
[0080] Furthermore, as the carriage assemblies may be easily
removed from the track, a high degree of modularity is provided. At
a mine site with several mills potentially of different sizes, the
carriage assemblies are able to be interchanged between different
mills as required for servicing. This provides a substantial cost
reduction as each mill does not require separate apparatus and
tools for liner replacement for example.
[0081] A number of further features will now be described.
[0082] Typically, the first carriage assembly is moveably mounted
to the track so that it is permitted to move (e.g. slide) along the
track. This provides the at least one tool with a second degree of
freedom being linear movement along the track. In one example, the
movement is parallel to a direction of elongation of a cylindrical
main body portion of the mill.
[0083] In a further example, the first carriage assembly may
provide five degrees of freedom to the at least one tool. A third
degree of freedom provided may be angular movement or rotation
about the first axis. A fourth degree of freedom provided may be
angular movement or rotation about a second axis orthogonal to the
first axis. A fifth degree of freedom may be linear movement about
a third axis orthogonal to both the first and second axes (i.e.
toward the mill). By providing the at least one tool with such
dexterity of movement, the position and orientation of the tool can
be precisely controlled allowing the tool to be used in the removal
of linerbolts in both the cylindrical main body portion and
frusto-conical end portions of the mill, including linerbolts that
may be at an oblique or skewed angle relative to the other
linerbolts.
[0084] In one example, the apparatus is further configured to
suspend and guide at least one platform and to provide the at least
one platform with at least two degrees of freedom, and wherein a
first degree of freedom provided to the at least one platform is
linear movement along an axis orthogonal to the surrounding floor
of the mill. The at least one platform can be utilised by workers
to perform manual tasks and may be equipped with manual tools such
as nut removal tools and the like to assist in removing the
linerbolts. The at least one platform may also enable workers to
manipulate the tool guided by the first carriage assembly, such as
a linerbolt removal tool.
[0085] Typically, the second degree of freedom provided to the at
least one platform is linear movement along the track. The at least
one platform is therefore able to move up and down and laterally
about the mill to the position desired by the worker.
[0086] In a further example, four degrees of freedom are provided
to the at least one platform, further including a third degree of
freedom being angular movement about the axis orthogonal to the
surrounding floor of the mill, and a fourth degree of freedom being
linear movement parallel to the surrounding floor of the mill (i.e.
towards and away from the mill). These further degrees of freedom
enable the platform to be positioned and oriented for example to
manipulate a linerbolt removal tool mounted to the first carriage
assembly that may be required to remove linerbolts from one of the
frusto-conical ends of the mill or linerbolts at an oblique or
skewed angle relative to the other linerbolts.
[0087] In one example, the first carriage assembly includes a first
carriage moveably mounted to the track for linear movement
therealong. A first post member is supported by the first carriage
and arranged to be orthogonal to the surrounding floor of the mill,
at least a part of the post member moveable along the first axis
orthogonal to the surrounding floor of the mill. The post member
may be arranged with respect to the first carriage to slide
relative thereto or alternatively at least a portion of the first
post member may be telescopically arranged to extend and
retract.
[0088] A first tool carriage for carrying the at least one tool is
mounted to the post member such that the tool carriage is provided
with angular movement about the first axis and angular movement
about a second axis orthogonal to the first axis. The tool carriage
further includes a linear slide mechanism allowing the at least one
tool to be slidably received thereby allowing the at least one tool
to move along a third axis orthogonal to both the first and second
axes. The angular movement of the tool carriage with respect to the
post may be achieved via any suitable coupling arrangement.
[0089] In a further example, the apparatus includes a second
carriage assembly for supporting the at least one platform, the
second carriage assembly including a second carriage moveably
mounted to the track for linear movement therealong. A second post
member is supported by the secondary carriage and arranged to be
orthogonal to the surrounding floor of the mill, at least a part of
the second post member moveable along an axis orthogonal to the
surrounding floor of the mill. The at least one platform is
rotatably coupled to a distal end of the second post member to
allow angular movement about the axis orthogonal to the surrounding
floor of the mill. The coupling may further permit linear movement
orthogonal to the second post member.
[0090] In the above described examples, the at least one work
platform is suspended and guided by a different carriage assembly
to the at least one tool. However this need not be the case, and in
other arrangements, the at least one platform and at least one tool
are both suspended and guided by the first carriage assembly.
[0091] Furthermore, whilst typically, there is only one fixed track
or monorail suspended above the mill, in other examples, more than
one track may be provided. In one example, a second track runs
parallel to the first track and the first carriage assembly is
moveably mounted to the first track whilst the second carriage
assembly is moveably mounted to the second track.
[0092] Typically, the at least one tool is a linerbolt removal tool
used for knocking out linerbolts and liners on a cylindrical main
body portion of the mill and knocking out linerbolts on a
frusto-conical end portion of the mill connected to said
cylindrical main body portion. Other tools however may be used
including for example high torque/impact nut removal tools and
cleaning tools such as an electric drill with wire brush used in
preparing the hole and/or cleaning the shell of the mill once the
Linerbolt has been removed. The various tools may be
interchangeably mounted to the first carriage assembly or
alternatively mounted in addition to the linerbolt removal
tool.
[0093] As previously described, typically the at least one platform
is a work platform for carrying one or more workers and positioning
them about the mill to carry out manual tasks as required.
[0094] In one example, there is provided an apparatus for
suspending and guiding at least one linerbolt removal tool and at
least one work platform externally about a grinding mill. The
apparatus includes a fixed track suspended above the grinding mill
and extending about an outer periphery thereof in a plane
substantially parallel to a surrounding floor of the mill. A first
carriage assembly is coupled to the track for supporting the at
least one linerbolt removal tool, the first carriage assembly
configured to provide the at least one linerbolt removal tool with
at least two degrees of freedom, and wherein a first degree of
freedom is linear movement along an axis orthogonal to the
surrounding floor of the mill. A second carriage assembly is also
coupled to the track for supporting the at least one work platform,
the second carriage assembly configured to provide the at least one
work platform with at least two degrees of freedom, and wherein a
first degree of freedom is linear movement along an axis orthogonal
to the surrounding floor of the mill. In this arrangement both the
platform carrying at least one worker and the linerbolt removal
tool can be positioned and oriented as desired in order to remove
linerbolts in both the cylindrical main body portion of the mill
and frusto-conical end sections of the mill.
[0095] In one example, in order to provide maximum dexterity to
both the linerbolt removal tool and work platform, the at least one
linerbolt removal tool is provided with five degrees of freedom and
the at least one work platform is provided with four degrees of
freedom as previously described.
[0096] Any suitable number of carriage assemblies may be used by
the apparatus for carrying a desired number of linerbolt removal
tools and/or work platforms. For example, a third carriage assembly
can be provided for supporting a second linerbolt removal tool
externally about the grinding mill. A fourth carriage assembly may
be provided for supporting a third linerbolt removal tool
externally about the grinding mill. A fifth carriage assembly may
be provided for supporting a fourth linerbolt removal tool
externally about the grinding mill, and a sixth carriage assembly
may be provided for supporting a second work platform externally
about the grinding mill.
[0097] Referring again to FIGS. 1A to 1C, the apparatus 1 for
suspending and guiding at least one tool or work platform
externally about a grinding mill 11 shall be described in further
detail.
[0098] In this example, grinding mill 11 is a SAG, AG or ball ore
mill of a conventional type which has sacrificial liners (not
shown) secured to the internal casing (not shown). Mill 11 has a
cylindrical main portion 16 disposed between two frusto-conical end
portions 12,17. Linerbolts 13,14 are used to secure the sacrificial
liners to mill 11, respectively through the cylindrical main
portion 16 and frusto-conical end portions 12,17.
[0099] The apparatus 1 includes a first carriage assembly 18
associated with first linerbolt removal tool 30 used for knocking
out linerbolts 13,14, on cylindrical main body portion 16 and on
frusto-conical end portions 12,17 of grinding mill 11. The first
carriage assembly 18 is moveable along a fixed track 20 suspended
above the grinding mill 11 and extending about an outer periphery
thereof in a plane substantially parallel to a surrounding floor of
the mill 11. The track 20 shown in FIG. 1A is of the monorail type
comprising a single rail elevated above the mill 11 and suspended
above the ground via a plurality of support pillars or poles. The
track structure is typically a permanently fixed structure built
around the mill 11.
[0100] The apparatus 1 further includes a second carriage assembly
19 associated with work platform 40 used for manual tasks on
cylindrical main body portion 16 and on frusto-conical end portions
12,17 of the grinding mill 11.
[0101] The first carriage assembly 18 provides no more than five
degrees of freedom to its associated linerbolt removal tool 30
while the second carriage assembly 19 provides no more than four
degrees of freedom to its associated work platform 40.
[0102] The first carriage assembly 18 includes a first carriage 7
mounted for travel along the fixed track 20 disposed outside and
surrounding the mill 11. In this regard, the first carriage 7 may
be configured to slidably engage with the track 20 via rollers or
the like, at least some of which are drivable to move the first
carriage 7 along the track. A substantially straight first rail or
post member 5, having a longitudinal axis orthogonal to the
surrounding floor of the mill 11 is mounted to the first carriage
7. Typically, the rail 5 is slidably mounted to the first carriage
7 so as to be moveable up and down normal to the track 20. Whilst
the entire rail 5 may be moveable, this need not be the case and in
other examples, a lower portion of the rail may be telescopically
moveable to extend and retract at least a portion of the rail
5.
[0103] A tool carriage 2 for carrying the linerbolt removal tool 30
is mounted beneath the first rail 5 at a distal end thereof. The
tool carriage 2 has a linerbolt removal tool 30 slidably mounted
thereon via a slide mechanism. The linerbolt removal tool 30 is
mounted to the tool carriage 2 and oriented such that its tool
centre can be located on a line L.sub.1 radiating from the axis of
rotation R of the mill 11 (see FIG. 1C), and its slide mechanism
allows it move along that line.
[0104] In the example shown, the apparatus 1 provides the Linerbolt
removal tool 30 with five degrees of freedom as illustrated most
clearly in FIG. 3, where the various degrees of freedom are
represented by arrows A.sub.1-A.sub.5. The travel of the first
carriage 7 along the track 20 is depicted by arrow A.sub.5 and the
travel of first tool carriage 2 along an axis orthogonal to the
surrounding floor of the mill 11 is shown by arrow A.sub.1. The
travel of linerbolt removal tool 30 along an axis orthogonal to
both A.sub.1 and A.sub.5 is depicted by A.sub.4. The travel along
A.sub.4 is achieved by the ability of the linerbolt removal tool 30
to slide with respect to the slide mechanism to which it is
mounted.
[0105] As the mill 11 consists of a cylindrical main body 16 with
frusto-conical ends 12,17, two additional axes of motion are
required to enable the tool 30 to be positioned and oriented with
respect to all linerbolts. The Linerbolt removal tool 30 is
therefore able to rotate about a vertical axis via rotation of tool
carriage 2 depicted by A.sub.2. Finally, the tool carriage 2 is
able to rotate about an axis orthogonal to both A.sub.1 and A.sub.5
depicted by arrow A.sub.3. This is typically achieved by a pivotal
connection between the coupling of the tool carriage 2 to the rail
5 and the slide mechanism to which the linerbolt removal tool 30 is
attached. This rotational movement allows the linerbolt removal
tool 30 to be angled up or down with respect to the mill 11.
[0106] The second carriage assembly 19 comprises a second carriage
6 mounted for travel on the fixed track 20 disposed outside and
surrounding mill 11. A substantially straight second rail or post
4, having a longitudinal axis orthogonal to the floor of mill 11 is
mounted to the secondary carriage 6. Work platform 40 is mounted
beneath the second rail 4 at a distal end thereof.
[0107] In the example shown, the apparatus 1 provides the work
platform 40 with four degrees of freedom as illustrated most
clearly in FIG. 4, where the various degrees of freedom are
represented by arrows A.sub.1, A.sub.2, A.sub.4, A.sub.5. The
travel of the second carriage 6 is depicted by arrow A.sub.5, the
travel of first work platform 3 is shown by arrow A.sub.1. As mill
11 consists of a cylindrical main body 16 with frusto-conical ends
12, 17, two additional axes of motion are required. A.sub.2 rotates
first work platform 3 about the axis A.sub.1 and A.sub.4 provides
linear motion parallel to the surrounding floor of the mill 11.
[0108] FIGS. 4 to 6 depict a second embodiment of an apparatus 1
for suspending and guiding multiple linerbolt removal tools
30,31,32,33 and work platforms 40,41 externally of a grinding mill
11.
[0109] Referring now to FIGS. 2A to 2C, there is shown a further
example of an apparatus 100 for suspending and guiding a plurality
of linerbolt removal tools 30,31,32,33 and work platforms 40,41
externally about a grinding mill 11. In this example, four
Linerbolt removal tools 30,31,32,33 are positioned about the mill
11, with tools 30,31 positioned adjacent one another on a first
side of the mill for operation at frusto-conical end 12 and one
half of the cylindrical main body section 16. Linerbolt removal
tools 32,33 are positioned adjacent each other on the other side of
the mill 11 for operation at frusto-conical end 17 and the other
half of the cylindrical main body section 16. As the mill is
rotated during maintenance, such an arrangement is able to
efficiently operate to remove all of the linerbolts as quickly as
possible so as to minimise the time in which the mill out of
operation during liner replacement.
[0110] Each linerbolt removal tool 30,31,32,33 operates in the same
manner as previously described having up to five degrees of freedom
for movement and positioning about the mill 5. Each linerbolt
removal tool 30,31,32,33 is mounted to a separate carriage assembly
that is moveable about the track as previously described.
[0111] In this example, two work platforms 40,41 are provided on
opposing side of the mill 11 adjacent to linerbolt removal tools
30,31 and 32,33 respectively for use therewith. Work platforms
40,41 are provided with up to four degrees of freedom as previously
described via mounting to respective carriage assemblies. In
practice, any suitable number or combination of linerbolt removal
tools and work platforms may be used during liner replacement.
[0112] Referring now to FIG. 5, there is shown an example of a
linerbolt removal tool 30 and work platform 40 mounted to the same
carriage assembly. This may be achieved in any suitable manner, and
in one example, the work platform 40 may be mounted to the slide
mechanism that the linerbolt removal tool is secured to.
Alternatively, the platform may be mounted to the rail or post
5.
[0113] It should be understood that in other examples, any of the
linerbolt removal tools of the above described examples could be
replaced with other tools, and work platforms could also have fixed
tools incorporated into their design. It should be also understood
that the addition or replacement of tools or other paraphernalia
will not inhibit or diminish the capability of the apparatus 1,100
to operate in a manual, semi-automated or fully automated
capacity.
[0114] In this regard, it is to be understood that the apparatus
1,100 could be used for manual, semi-automated or fully automated
removal of linerbolts and liners, and manual or semi-automated work
platform positioning.
[0115] In one example, a linerbolt removal tool is able to be
auto-positioned about the mill for removal of linerbolts. The
position of each linerbolt relative to the mill may be determined
by mapping so that the coordinates of each linerbolt are known with
respect to a reference location. A tool controller or similar
processing system may be provided with the coordinates of each
linerbolt and programmed to move the tool in a systematic way to
each bolt. For example, the tool may be positioned with respect to
a first bolt so that the operator can manipulate the tool to remove
the bolt. The operator may then provide input to the tool
controller (for example via a lever or button) which is responsive
to drive the tool to the position of a second bolt for removal. In
this semi-autonomous way the tool can be moved about the mill for
accurate positioning with respect to each bolt for the operator to
remove. In an autonomous context, the tool may be programmed to be
positioned relative to a bolt, accurately aligned with respect to
the bolt and then actuated to remove the bolt.
[0116] According to at least one example, the above described
apparatus provides a convenient, safe and efficient way to suspend
and guide tools or platforms externally about a mill during liner
replacement. The tools are suspended in a stable and secure manner
which provides a safer environment for an operator when compared to
systems in which tools are suspended by hanging cables and free to
swing about. The ability to position and orient the tool with
respect to the mill by providing up to five degrees of freedom is
advantageous as a significant area of the mill (including both the
main body portion and frusto-conical ends) can be accessed by a
single tool, and linerbolts that are oblique or skewed can be also
be handled efficiently. Furthermore, as the carriage assemblies are
easily removed from the track, a high degree of modularity is
provided. At a mine site with several mills potentially of
different sizes, the carriage assemblies can be interchanged
between different mills as required for servicing. This provides a
substantial cost reduction as each mill does not require separate
apparatus and tools for liner replacement.
[0117] The ability for each tool to access a large portion of the
mill also means that liner replacement can be performed more
efficiently requiring less mill rotations and time out of service.
This further equates to a significant cost saving for the mill
operator.
[0118] Throughout this specification and claims which follow,
unless the context requires otherwise, the word "comprise", and
variations such as "comprises" or "comprising", will be understood
to imply the inclusion of a stated integer or group of integers or
steps but not the exclusion of any other integer or group of
integers.
[0119] Persons skilled in the art will appreciate that numerous
variations and modifications will become apparent. All such
variations and modifications which become apparent to persons
skilled in the art, should be considered to fall within the spirit
and scope that the invention broadly appearing before
described.
* * * * *