WO2003022654A1

WO2003022654A1 - Conduit conveyor

Info

Publication number: WO2003022654A1
Application number: PCT/AU2002/001249
Authority: WO
Inventors: Kimberley Vere Sadleir
Original assignee: Kimberley Vere Sadleir
Priority date: 2001-09-13
Filing date: 2002-09-13
Publication date: 2003-03-20

Abstract

A conduit conveyor (10, 200, 300) including a conduit (12) capable of being laid above and/or below ground from a source to a destination between 500 m to 1,000 kilometres apart and a conveyor (14, 310) having drive mechanisms (16), including bogies (64), attached to the conveyor (14, 310) for driving the conveyor (14, 310) along the conduit (12). The conduit (12) is relatively flexible along its length to follow undulating terrain and is self-supporting to span significant gaps up to 20 metres. The conduit conveyor (10, 200, 300) has the advantages of trains and conveyors without their inherent disadvantages.

Description

CONDUIT CONVEYOR

FIELD OF THE INVENTION

The present invention relates to a conduit conveyor,

More particularly the present invention relates to a conveyor for transporting bulk, particulate or discrete materials within a conduit between two or more spaced apart locations.

The conduit is typically a tube that acts as a self-supporting structural member that is capable of spanning a significant gap, and relatively flexible to follow undulations in terrain and to follow bends.

BACKGROUND OF THE INVENTION

The conduit conveyor of the present invention originated from the need to access a mineral sands deposit located in an environmentally sensitive area. Trucks, rail and conveyors were ruled out on noise, dust, safety and visual pollution grounds. A slurry pipeline was the only possible environmental solution but the abrasive nature of the sands meant that slurry or air assisted solutions had problems that rendered them impractical.

The proposed solution was to use a conveyor belt with wheels attached to the belt so it could travel in a special profile pipe, which could be installed either above or below ground.

The CONDUIT CONVEYOR of the present invention has competitive advantages including:-

* Transport of bulk solids through environmentally sensitive areas, safely, and quietly * Elimination of dust

* Substantially eliminates noise (when buried)

* Reduction of impact on wildlife and flora

* Improved social acceptance - minimised impact on existing communities

* Combined capital and operating cost of significantly less than that of conventional conveyors or railways, and substantially less than the cost of trucking

* Use of around l/7th of the energy of a standard conveyor

* Capability to travel over very long distances (500+ km) * Able to turning corners (as low as 100m radius) to maximize strategic routing

* Single point maintenance with electronic monitoring of serviceable parts

The CONDUIT CONVEY or the present invention is typically around 500 m to 400 km in length, around 500 mm to 700 mm in height, around 400 mm to 500 mm in width, with a wall thickness of around 2 to 3 mm, has per axle loads of around 1 to 2 tonnes, is fully automated, has nearly total energy recovery when traversing undulating terrain, and has both relatively low wind resistance and low rolling resistance.

The following table shows a general comparison between the projected operating costs of the CONDUIT CONVEYOR of the present invention and those of other bulk handling systems measured on a per kilometre basis:

Overview

Existing solutions for the transport of bulk materials presently include:

* Trucks - including large rear-loading dump-trucks on mines sites - and articulated road-trains for over-land haulage.

* Rail - large diesel locomotives pulling trains of 100 to 200 ore wagons.

* Conveyors - including long overland systems 10, 20, 30 km or more - plus shorter loading conveyors at ports for blending from stockpiles and for loading directly on to very large ships.

Mining companies use one or more of these bulk transport systems in their supply chain.

Each of these current bulk transport systems has advantages and disadvantages compared to each other in various scenarios of the mining supply chain. In the appropriate mining transportation scenarios, the CONDUIT CONVEYOR of the present invention offers clear advantages over current bulk handling systems. Briefly the advantages and problems of the other mining bulk transportation systems are a follows: Trucks & Road Trains

Offer flexibility, rapid expansion and contraction depending on production rates. On the downside, they are relatively expensive, labour intensive, with significant environmental problems in dust, noise, visual pollution, road safety and community issues.

The truck and road trains are typically 10 to 60 metres in length, 3 to 6 metres in height, 2 to 4 metres in width, run on a compacted flat surface and are usually manned. When travelling down hill, trucks and road trains have limited ability to recover energy to assist in climbing up an adjacent hill. When there is an overall height drop from loading point to discharge point, the typical truck or road train has no ability to recover energy to assist in the return journey. The truck conveying vehicle requires soft tyres and a very flexible suspension system to cope with severe undulations in the supporting surface and high rolling friction pneumatic tyres. Also trucks and road trains travel at varying speeds, typically between 10 kph and 120 kph depending on the nature of the terrain that they traverse. Further, trucks and road trains suffer considerably in the operating efficiency from the effects of wind resistance and rolling resistance. Still further, trucks and road trains require roads to be laid between the start and finish points of their intended journey - which can be very expensive.

The CONDUIT CONVEYOR of the present invention overcomes all of the difficulties of trucks and road trains in relation to energy recovery, wind and rolling resistance. The CONDUIT CONVEYOR of the present invention can also travel at substantially constant speeds, even over undulating terrain, and does not require a driver.

Rail

Currently rail offers the best long haul solution for large-scale transportation of bulk solids. The low rolling friction of steel wheels on steel rails (as low as l/20th of road tyre friction) and reduced labour component make this possible.

But the large-scale capital investment in rail and rolling stock (around A$l million to A$1.8 million /kilometre) make the rail option generally only suitable where production exceeds 15 years, distance exceeds 50 kilometres and tonnages exceed 5 million tonnes/annum.

Rail requires specialist engine drivers plus a host of maintenance specialists using large workshop facilities plus high tech systems like mobile rail spectrometers (to inspect the integrity of the railway line) etc.

Also, rail still has the problem of varying speeds depending upon the terrain and can only recover part of the energy in downhill situations.

Although relatively efficient for large tonnages, rail is not an optimum use of capital investment since the expensive rail system is only utilized around 1% of the time (i.e. when ore trains are actually travelling the section of rail). Railway systems are very expensive to maintain with track maintenance, repairs to ore cars, wheels, axles, plus regular replacement or upgrades of the diesel locomotives.

The train is formed of rail carriages of typically 8 to 20 metres in length, 3 to 5 metres in height. 2 to 3 metres in width, is usually driven by a person, and has significant wind resistance. The ore trains having to cope with over 70 tonnes per bogie and requires considerable ballast (between 5 to 6 metres wide and 0.5 to 1.5 metres deep) to form a suitable base to support the railway lines for the trains to run on.

The CONDUIT CONVEYOR of the present invention has the advantages of railway systems without the disadvantages in high wear, high axle loads and high capital and operating costs.

Conveyor Systems

Conveyors are large structures that require a high degree of engineering expertise in design and construction. They require careful alignment plus steel supports usually set in concrete footings.

Conveyors are typically either a tensioned belt ("belt conveyor") travelling over mechanical rollers or multiple chain links "chain conveyor") travelling on rails supported by a metal frame. The belt conveyor is driven by very large electric motors and pulley systems at both ends. The chain conveyor is usually driven by very large electric motors with drive sprocket systems at both ends, the sprockets engaging a chain attached to the conveyor plates.

Being a continuous bulk transportation system, conveyors are cost efficient and less expensive to operate than trucks or rail over limited distances. The belt or chain tension factor means that they are limited in distance and must be put in several flights to cover distances over 20 kilometres. Conveyors can travel around horizontal curves but have a very limited ability to turn corners.

Compared to trucks conveyors do not require large numbers of operating staff or maintenance personnel but ongoing maintenance of belts and rollers is an expensive part of the system. For instance, maintenance staff have to constantly inspect conveyor systems listening for noisy or damaged roller bearings. The conveyor belt travels over mechanical rollers causing friction and wear. The rollers have a much higher rolling coefficient of friction (about 10-20 times higher) than steel rail wheels on steel tracks.

Because of this higher friction, conveyors use more electricity, and electricity costs are the highest ongoing cost of operating a mining conveyor system.

Conveyors are large above ground structures, visually unattractive, noisy, can be polluting with dust, can cause problems in environmentally sensitive areas, and can be socially unacceptable in areas where they impact on communities.

A typical conveyor belt has a practical length of up to around 20 km, typically runs on steel rollers attached to a stationary frame, requires monitoring and maintenance along it's entire length, and has high rolling friction rubber on steel rollers.

A typical chain conveyor is similar to the belt conveyor except that it has a practical length of up to around 2 km.

The CONDUIT CONVEYOR of the present invention has the advantages of conventional belt and chain conveyors without the disadvantages in relation to environmental impact, limited distance of travel, inability to turn corners and high friction and wear.

SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide a conduit conveyor that substantially overcomes the disadvantages of conventional conveying systems.

In accordance with one aspect of the present invention there is provided a conduit conveyor including:

a conveying means having a plurality of material carrying means connected endwise for receiving materials for transportation between spaced apart locations, and a plurality of wheels coupled to each of the material carrying means for enabling rolling motion of the material carrying means between said spaced apart locations;

a conduit constructed from a plurality of structural members of substantially uniform cross section, connected endwise to form a self supporting structure capable of spanning a significant gap, the structural members being relatively flexible along their length for allowing the conduit to at least partially follow undulations in terrain and to turn bends, the conduit having track means for receiving the said wheels for carrying the conveying means along its length;

a drive means including a plurality of electric motors connected to at least some of the material carrying means for driving at least some of the said wheels;

an electrical distribution means for carrying electrical power along the conduit to the conveying means; and,

power transfer means for transferring the electrical power from the electrical distribution means to the said electric motors.

In the context of the present invention the term "significant" in relation to spanning gaps is to span a gap in excess of 1 metre and more typically spanning gaps in excess of 10 metres and up to 20 metres.

Also, in the context of the present invention the term "relatively flexible", in relation to the conduit, means that the conduit can follow undulations with a radius of curvature of greater than 200 times the height of the tube and turn a bend with a radius of curvature of greater than about 200 times the width of the tube. This flexibility does not refer to bends fabricated into the conduit for performing sharper bends or more severe undulations.

BRIEF DESCRIPTION OF THE DRAWING(S)

Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which:-

Figure 1 is a schematic side view of an ingress end of a conduit conveyor in accordance with one aspect of the present invention, showing ore being dumped onto a wheeled conveyor belt;

Figure 2 is a schematic side view of an egress end of a conduit conveyor in accordance with one aspect of the present invention, showing ore being offloaded from the wheeled conveyor belt;

Figure 3 is a schematic cross-sectional view of the conduit conveyor of the present invention showing the wheeled conveyor belt in to and from directions of travel, with a drive mechanism and a braking mechanism; Figure 4 is a schematic cross-sectional view of the conduit conveyor of Figure 3 showing a cleaning mechanism;

Figure 5 is a perspective view seen from above of a belt guide of the conduit conveyor of Figures 1 and 4;

Figure 6a is a cross-sectional view of the conveyor belt of Figures 1 to 5, shown with a bogie, and with a replaceable wear belt attached;

Figure 6b is a cross-sectional view of a system of connecting grooves and ridges of the replaceable wear belt of Figure 6a, shown on a larger scale;

Figure 7 is a cross-sectional view of a conduit conveyor in accordance with another embodiment of the present invention, shown in use with boxed components; and,

Figure 8 is a cross-sectional plan view of a conduit conveyor in accordance with yet another embodiment of the present invention, showing a plurality of articulated platforms joined endwise and traversing a tortuous path.

DESCRIPTION OF EXEMPLARY EMBODIMENT(S)

In Figures 1 to 6b there is shown a conduit conveyor 10 in accordance with one embodiment of the present invention.

The conduit conveyor 10 comprises a conduit 12, a conveyor 14, a drive mechanism 16, a belt cleaner 18, a conduit cleaner 20, a maintenance bay 22, a monitoring system 24, a belt guide 26, and an inverting station 28.

CONDUIT

The conduit 12 has an ingress end 40, shown in Figure 1, an egress end 42. shown in Figure 2 and an intervening tube 44. Typically the conduit 12 has two tubes 46 and 48. as shown in Figures 3 and 4, conjoined. In the present embodiment the tubes 46 and 48 are located one on top of the other, although it is to be understood that they could be disposed side by side. Typically, the conduit 12 is formed of metals materials. The tubes 46 and 48 could be roll formed from metals materials and then welded together along join edges 50.

The tubes 46 and 48 have a profile that forms two rails 52 disposed longitudinally of the conduit 12 and substantially mutually parallel so that the conveyor 14 can run along the rails 52. It is preferred that the conduit 12 also has a replaceable wear strip 54 disposed on top of each of the rails 52. The wear strips 54 have a profile that matches the profile of the rails 52. It is intended that the wear strips 54 be replaced once they become worn and thereby protect the tubes 46 and 48 from damage and wear. Typically the wear strips 54 are made from relatively high carbon steel.

In the present embodiment the upper tube 46 is intended to carry the conveyor 14 laden with ore or other particulate material from a source to a destination. The lower tube 48 is intended to carry the conveyor 14 unladen from the destination back to the source. Hence the lower tube 48 can be smaller in cross-section than the upper tube 46.

Typically, the conduit 12 has the following dimensions: a length of between 100 metres to 1,000 kilometres (virtually unlimited length is possible), more particularly between 500 metres and 400 kilometres; a height of between 200 mm and 2 metres, more particularly between 500 mm and 700 mm; a width of between 100 mm and 1 metre, more particularly between 400 mm and 500 mm; and a wall thickness of between 1 mm and 5 mm, more particularly between 2 and 3 mm. Also, the conduit 12 is relatively light in weight compared with its volume.

The conduit 12 is typically formed from a plurality of substantially identical structural members having a substantially constant cross-section throughout their length. The structural members are connected endwise to form the conduit 12.

The structural members are relatively flexible along their length for allowing the conduit 12 to at least partially follow undulations in terrain and to turn bends. The structural members are sufficiently flexible to follow undulations with a radius of curvature of greater than 200 times the height of the conduit 12 and turn a bend with a radius of curvature of greater than about 200 times the width of the conduit 12. It is envisaged that bends could also be preformed into the structure members to follow sharper undulations and tighter bends.

The structural members are preferably substantially self-supporting, in that they can span a significant gap, such as a gap in excess of 1 metre and more typically in excess of 10 metres and up to about 20 metres.

The conduit 12 is of substantially unitary construction. That is to say that the structural members of the conduit 12 are substantially unitary in construction. Or put another way the structural members are formed in only one or two pieces.

It is envisaged that some structural members have specific purposes such as to allow access into and inspection of the conduit 12 and that these particular structural members will not be of constant cross-section throughout their entire length.

It is envisaged that the conduit 12 could be formed by extruding plastics material or aluminium or the like through a die.

CONVEYOR

The conveyor 14 includes a conveyor belt 60, a plurality of frames 62, a plurality of bogies 64 and a replaceable liner 66.

The conveyor belt 60 is typically formed in segments joined endwise in know manner. The conveyor belt 60 has a length that is greater than the length of the two tubes 46 and 48 combined, or greater than twice the length of the conduit 12. The conveyor belt 60 is preferably cupped, particularly is shown in Figures 3 and 4, for receiving particulate material, such as ore or the like.

The plurality of frames 62 are spaced at substantially regular intervals along the entire length of the conveyor belt 60. The frames 62 include a base 70 and two sides 72. The frames 62 are each typically fixed to the underside of the conveyor belt 60 with rivets or the like (not shown). For this reason each of the frames 62 preferably also includes a top plate 74. The top plate 74 and the base 70 sandwich the conveyor belt 60 and are typically held in place with the rivets.

The sides 72 may be hingedly coupled to the base 70 to allow the conveyor belt 60 to flatten out when it changes direction in the vicinity of the belt guides 24, as shown in Figures 1, 2 and 5. Alternatively the sides 72 could be rigidly coupled to the base 70, thus preventing flattening out of the conveyor belt 60 at the belt guide 26.

The bogies 64 are journalled to the underside of the frames 62 for travelling in the conduit 12 with the conveyor belt 60. The bogies 64 each have two wheels 80, which are supported upon the wear strips 54 upon the rails 52. Pairs of the wheels 80 are mounted upon an axel 82. The profile of the outer lower portion of the wheels 80 substantially matches the profile of the wear strip 54. This has the advantage of keeping the wheels 80 running on the rails 52 and reduces the likelihood of derailment. It is to be noted that the conveyor belt 60 sags between adjacent bogies 64. This has the desirable effect of tensioning the conveyor belt 60 under the load of the ore and for acting as a means for absorbing shock.

So as to prevent the bogies 64 from tipping over the base 70 of the frame 62 has a width that is typically between 1 to 3.5 times the diameter of the wheels 80, and more typically between 1.5 to 2 times the diameter of the wheels 80.

Optionally, the replaceable liner 66 is used to protect the conveyor belt 60. This may be done where the conveyor belt 60 is made from costly materials and/or subjected to very abrasive loads. As shown in Figure 6b the replaceable liner 66 conveniently has connecting ridges 90 and the conveyor belt 60 has connecting grooves 92 to facilitate the easy coupling of the replaceable liner 66 to the conveyor belt 60.

It is also envisaged that brackets 94 could be used at the ends of side 72 of the frame 62 to clamp over and hold the replaceable liner 66 onto the conveyor belt 60 as shown in Figure 6a.

It is envisaged that other means could be used to removably couple the replaceable liner 66 onto the conveyor belt 60. For example, industrial Velcro®, or other materials of the hook and loop type.

DRIVE MECHANISM

The drive mechanism 16 includes a plurality of electric motors 100. an electrical distribution system 102 and an electrical power transfer system 104.

One of the electric motors 100 is mounted upon the axel 82 of one of the bogies 64. But not all bogies 64 have one of the electric motors 100 to drive it. For example, there may be 10 or 20 bogies 64 without electric motors between every two bogies 64 that do have electric motors 100.

The electrical distribution system 102 includes a high voltage electrical cable 1 10 conveniently laid in a trough in each one of the tubes 46 and 48, and a low voltage high current bus bar 1 12 laid upon the cable 1 10. The electrical power in the cable 1 10 induces power in the bus bar 1 12 in known manner.

The power transfer system 104 typically includes electrically conductive brushes or the like (not shown) for collecting power from the bus bar 1 12 and supplying it to the electric motor 100. Hence, the conveyor 12 has drive power applied to it at regular intervals along its length. This greatly reduces the power needs of each individual motor 100, reduces the tension developed in the conveyor belt 60, and makes it feasible to make the conveyor belt 60 longer than 20 kilometres. The distributed nature of the drive power also means that a thinner cross-section of conveyor belt 60 can be used, which also reduces weight and cost factors.

The drive mechanism 16 also has a brake system 114 including a brake disk 1 16 and a brake calliper 118. The brake system 114 is typically electrically controlled to slow and/or stop the motion of the conveyor belt 60.

BELT CLEANER

Particularly as shown in Figure 1 the belt cleaner 18 is located at the ingress end 40 of the conduit 12. The belt cleaner 18 includes brushes or belted flaps to slide over the ore after it has been dumped onto the conveyor belt 60 to reduce the amount of dust that is airborne in the conduit 12.

The belt cleaner 18 typically also includes a vacuum cleaner for extracting any dust that may be airborne at the ingress end 40 of the conduit 12.

CONDUIT CLEANER

Particularly as shown in Figure 4 the conduit cleaner 20 includes a vacuum cleaner 120 and a series of brushes 122. The vacuum cleaner 120 is attached to one of the frames 62 and has a series of nozzles 124 directed to the upwardly facing surfaces of the tubes 46 and 48. The vacuum cleaner 120 also has a reservoir 126 for storing dust collected from inside the tubes 46 and 48. The vacuum cleaner 120 derives electrical power from the bus bar 112 in the same way that the drive motors 1 10 do.

The series of brushes 122 are arranged to sweep along the upwardly facing surfaces of the tubes 46 and 48. The brushes 122 dislodge the dust and facilitate its being collected by the vacuum cleaner 120.

Typically a number of the conduit cleaners 20 are disposed at regular intervals along the length of the conveyor belt 60.

The vacuum cleaners 120 are arranged to dump the collected dust when they exit the egress end 42 of the conduit 12. Hence each vacuum cleaner 120 cleans both tubes 46 and 48. And for this reason it is preferred that the conveyor belt 60 be oriented upright when in the lower conduit 48 on the return trip to the source of the ore. Also, it is preferred that the tubes 46 and 48 be of substantially the same shape in their lower regions.

It is important to remove any dust that enters the conduit 12 otherwise the dust will impair the conduction of electrical power to the drive motors 100, collect around the rails 52 and eventually render the conduit conveyor 10 unusable.

MAINTENANCE BA Y

The maintenance bay 22 includes a belt lifter 130 arranged to lift a small section of the conveyor belt 60 proximate a set of the bogies 64 in order to lift the bogies off the guide rails so that the bogies, the frames 62, the drive mechanism 16 and the conduit cleaner 20 can be serviced. The maintenance bay 22 is proximate the egress end 42 of the conduit 12. It is envisaged that components requiring servicing will be removed and replaced during a maintenance cycle of operation of the conduit conveyor 10 during which time ore is preferably not being transported by the conveyor belt 60 (although such is not essential).

MONITORING SYSTEM

The monitoring system 24 includes a monitoring bay 140 and a mobile video camera 142. particularly as shown in Figures 1 and 4.

The monitoring bay 140 is programmed to measure critical wear factors of the bogies 64 and drive mechanisms 16 as they pass prior to dumping the ore off the conveyor belt 60. These critical wear factors typically include bearing temperature, wheel out of round, bearing noise, vacuum cleaning function, wear on electrical power pickup brushes, and the like.

Each bogie 64 is provided with an identity tag that can be interrogated by the monitoring bay 140. Any wear factor that is found to be out of acceptable tolerances for a particular bogie 64 is stored along with the identity tag details for that bogie 64. Then during a maintenance cycle of operation the monitoring system 24 liases with a control system of the drive mechanism 16 to drive the conveyor belt 60 until the bogie 64 requiring servicing is located at the maintenance bay 22. In such manner a program of continuous preventative maintenance can be performed to keep the conduit conveyor 10 operational for its entire serviceable life. The video camera 142 is located within the tube 46 and runs on an overhead rail 144. The video camera 142 is preferably battery powered and arranged for charging from the bus bar 112. The video camera 142 can move independently of the conveyor belt 60 and can function independent of the electrical power distribution system 110 so that in the event of a power failure the video camera 142 is still able to inspect the interior of the tube 46.

The video camera 142 is controllable to take images of the conveyor belt 60 and the ore and relay them to a remote control station, typically located adjacent either the ingress end 40 or the egress end 42 of the conduit 12. Typically, the electrical signals representing the images are transmitted over the bus bars 112 to the control station.

BELT GUIDE

Particularly as shown in Figures 1, 2 and 5, the belt guide 26 is substantially C shaped when viewed in elevation and typically has channels 160 for receiving the wheels 80 of the bogies 64 for guiding the conveyor belt 60 at the end of its limits of travel. The belt guide 26 maintains the tension in the conveyor belt 60 whilst it changes direction and hence there is one belt guide 26 located spaced from each end of the conduit 12. The belt guides 26 are preferably passive and do not serve to drive the conveyor belt 60.

The conduit conveyor 10 also includes rails (not shown) located at the ends 40 and 42 of the conduit 12 for carrying the bogies 64 when the conveyor 14 is outside the confines of the conduit 12. These rails deliver the conveyor belt 60 to the belt guides 26 and return the conveyor belt 60 to the conduit 12.

INVER TING ST A TION

Particularly as shown in Figures 1 and 2 the inverting station 28 is located between a lowermost end of the belt guide 26 and the conduit 12. The inverting station 28 is a region where the conveyor belt 60 is made to turn through 180 degrees of rotation about its length. Optionally rails may be used to guide the conveyor belt 60 during this rotation, however, the strength of the conveyor belt 60 is sufficient to align the conveyor belt 60.

The inverting stations 28 ensure that the conveyor belt 60 is always upright when travelling in the conduit 12. This is important for the proper operation of the conduit cleaners 20 as described hereinabove. INSTALLATION

The structural members are typically rolled and transported to a location for construction of a conduit 12. The tubes 46 and 48 are conveniently welded together along their join edge 50.

The conduit conveyor 10 of the present invention is typically installed by digging a shallow trench, connecting the structural members end to end and laying them in the trench to form the conduit 12. In this way the conduit 12 can be partially or completely covered with soil, which reduces the environmental impact of the conduit 12 and the noise pollution. Where necessary the conduit 12 can be laid upon a small bed of ballast with posts or the like to inhibit transverse movement of the conduit 12.

Lengths of the conveyor belt 12 are inserted into the conduit 12 as it is laid and joined together in known manner.

The conduit 12 is laid from a source, such as, for example, a source of ore to a destination, such as, for example a port for shipping the ore to another location for further processing.

At the two ends 40 and 42 of the conduit 12 the conveyor belt 60 is twisted through 180 degrees at the inverting stations 28.

OPERATION

In use, the drive mechanisms 16 are supplied with electrical power via the bus bars 112 to drive the conveyor belt 60 along the tubes 46 and 48. Ore is dumped onto the conveyor belt 60 at the ingress end 40 of the conduit 12. The belt cleaner 18 removes dust from the conduit 12 at the ingress end 40.

As the conveyor belt 12 travels along the tube 46 it is monitored by the video cameras 142 moving on the overhead rail 144.

One in every 10 to 20 bogies is provided with electrical power to drive the conveyor belt 60 on its journey. The conduit cleaners 20 maintain the interior of the tubes 46 and 48 substantially free from dust (or otherwise at levels of dust under which the conduit conveyor 10 can still function effectively).

During the travel of the conveyor belt 60 the wear strips 54 protect the rails 52 and substantially prevent the wheels 80 from running off the rails 52.

At the egress end 42 of the conduit 12 the conveyor belt 60 meets the maintenance bay whereat the components of the conveyor 14, the drive mechanism 16 and the conduit cleaner 20 can be replaced during a maintenance cycle of operation.

At the monitoring bay 140 the components of the conveyor 14, the drive mechanism 16 and the conduit cleaner 20 are monitored for critical wear factors and flagged in the event that any exceed allowable working tolerances.

The conveyor belt 60 then reaches the belt guide 26 where it turns through 180 degrees about a transverse axis and in so doing offloads the ore onto a stock pile or the like.

Next the conveyor belt 60 traverses the inverting station 64 whereat it turns though 180 degrees about a longitudinal axis so that it enters the tube 48 upright.

OTHER EMBODIMENTS

In Figure 7 there is shown a conduit conveyor 200 in accordance with another embodiment of the present invention.

The conduit conveyor 200 is similar to the conduit conveyor 10 and like numerals denote like parts.

The conduit conveyor 200 differs from the conduit conveyor 10 in that the conveyor belt does not go through a 180 degree twist about a longitudinal axis. Hence the conveyor belt 60 returns upside down in the tube 48.

The conduit conveyor 200 is intended for use in transporting boxed materials from a source to a destination.

In Figure 8 there is shown a conduit conveyor 300 in accordance with a further embodiment of the present invention.

The conduit conveyor 300 is similar to the conduit conveyor 10 and like numerals denote like parts.

The conduit conveyor 300 differs from the conduit conveyor 10 in that it has a conveyor belt 310 formed from a plurality of platforms 312 supported upon the bogies 64. Typically there is one bogie per platform 312. The platforms 312 are connected by couplings 314. The coupling 314 use pins or the like to allow pivotal movement of endwise adjacent platforms 312.

In such manner the conveyor belt 310 can traverse quite tortuous paths.

Also, the motors 100 are connected to drive individual wheels 80 so that the platforms 312 can turn relatively sharp corners.

The conduit conveyors 10, 200 and 300 of the present invention have the advantages of rail and conveyors without the inherent disadvantages of either. Thereby the conduit conveyors 10, 200 and 300 are relatively inexpensive to install and operate, have a low impact on the environment. are relatively easy to maintain and operate and are very efficient.

Modifications and variations such as would be apparent to a skilled addressee are considered within the scope of the present invention. For example, the tubes 46 and 48 could be the same shape and size.

Claims

CLAIMS DEFINING THE INVENTION

1. A conduit conveyor including:

a conduit constructed from a plurality of structural members of substantially uniform cross section, connected endwise to form a self supporting structure capable of spanning a significant gap, the structural members being relatively flexible along their length for allowing the conduit to at least partially follow undulations in terrain and to turn bends, the conduit having track means for receiving the wheels for carrying the conveying means along its length;

2. A conduit conveyor according to Claim 1, in which the conduit is of substantially unitary construction.

3. A conduit conveyor according to any one of Claim 1 or 2. in which the conduit is arranged in a configuration chosen from a linear placement between two spaced apart locations, an endless loop about a horizontal plane and an endless loop about a vertical plane.

4. A conduit conveyor according to Claim 2. in which the conduit includes two tubes conjoined, one of the tubes carrying the conveying means on its journey to its destination and the other tube carrying the conveying means back to its source.

5. A conduit conveyor according to any one of Claims 1 to 4. in which the material carrying means is a continuous conveyor belt whose length is at least as long as the conduit.

6. A conduit conveyor according to Claim 4 or 5, in which the conveying means is capable of longitudinal twist for allowing a portion of the conveying means to turn through at least 180 degrees of rotation about its longitudinal axis for allowing the conveying means to turn over when outside of the conduit for loading and unloading materials for transportation.

7. A conduit conveyor according to Claim 6, including a guide means for guiding the conveying means as it reverses its direction of travel.

8. A conduit conveyor according to Claim 1, in which the material carrying means is chosen from a group including a plurality of articulated platforms joined endwise, and a continuous flexible material supporting web.

9. A conduit conveyor according to Claim 1 , in which the conduit is formed of two tubes conjoined along their length, the conveying means being endless and running through both of the tubes and exiting the tubes at their ends for loading and unloading materials for transportation, and the conveying means being capable of twisting longitudinally for allowing a portion of the conveying means to turn through at least 180 degrees of rotation along its longitudinal axis for allowing the conveying means to turn over for said loading and unloading materials.

10. A conduit conveyor according to Claim 9. in which the said two tubes are located one on top of the other with their ends substantially coplanar, and an end ramp disposed proximate the ends of the two tubes for guiding the conveying means from the end of one of the tubes to the beginning of the other tube for said loading and unloading of materials.

11. A conduit conveyor according to any one of the preceding Claims, in which the conveying means has a replaceable liner and attachment means for attaching the replaceable liner to the conveying means.

12. A conduit conveyor according to Claim 1, in which electrical distribution means includes a bus bar, and the transfer means includes electric contacts capable of bearing against the bus bar for supplying electrical power to the electric motor.

13. A conduit conveyor according to any one of the preceding Claims, including camera means for providing visual monitoring of the operation of the conveying means.

14. A conduit conveyor according to any one of the preceding Claims, including a vacuum cleaner means for removing dust from the conduit.

15. A conduit conveyor according to any one of the preceding Claims, including monitoring means for monitoring the state of maintenance of the components of the conveying means and the conduit having a gap located intermediate its length whereat access is provided to the conveying means for allowing servicing of conveying means.

16. A conduit conveyor according to any one of the preceding Claims, including a vacuum cleaner means for removing dust from the conduit.

17. A conduit conveyor according to Claim 1, also including a computerised monitoring system for measuring critical wear factors in the conveying means, identification means for identifying components of the conveying means that exceed said critical wear factors, a maintenance bay, and means for forwarding the identified components to the maintenance bay for replacement.

18. A method of maintenance of the conduit conveyor of Claim 1. the method including the steps of:

monitoring components for critical wear factors of the conveying means;

identifying components of the conveying means that exceed said critical wear factors;

forwarding the conveying means within the conduit until the identified components arrive at a maintenance bay; and,

replacing the identified components.

19. A method of cleaning the conduit conveyor of Claim 1 , the method including the steps of:

collecting dust in the conduit with a vacuum cleaner means attached to the conveying means;

storing said dust in the vacuum cleaner; and,

dumping said dust from the vacuum cleaner once the vacuum cleaner means exits the conduit.