AU2008264236B2

AU2008264236B2 - A Barrier System for Material Projected Along a Trajectory Path

Info

Publication number: AU2008264236B2
Application number: AU2008264236A
Authority: AU
Inventors: Peter Wallace
Original assignee: C V R Holdings Pty Ltd
Current assignee: Cvr Holdings Pty Ltd
Priority date: 2000-12-28
Filing date: 2008-12-29
Publication date: 2010-04-22
Anticipated expiration: 2021-12-27
Also published as: AU2008264236A1; AUPR233900A0; WO2002053476A1

Description

P/001011 28/5191 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Name of Applicant: Wallace & Sons Research Pty Ltd Actual Inventor Peter Wallace Address for service is: WRAYS Ground Floor, 56 Ord Street West Perth WA 6005 Attorney code: WR Invention Title: A Barier System for Material Projected Along a Trajectory Path The following statement is a full description of this invention, including the best method of performing it known to me:- "Barrier System" Field of the Invention This invention relates to a barrier system for material moving along a trajectory path. 5 The invention has been devised particularly, although not solely, for use in transfer chutes in materials conveyor systems where the barrier system is intended to be installed in the trajectory path of particulate material discharging from a conVeyor. Background Art 10 Materials handling systems for particulate material (such as iron ore and other mined materials) typically employ conveyors for conveying the particulate material. The particulate material is conveyed to a discharge location at which the particulate material is discharged into a chute. Typically, the chute is a transfer chute or a head chute. 15 As the particulate material discharges from the conveyor into the chute, it follows ~/trajetorypah. Typted #y, at least some of the particulate material discharging along the trajectory path into the chute impacts upon a wall 'of the chute. sc causing wear to the chute. With a view to reducing the extent of wear on the wall of the chute, it is common 20 to line at least the area of the wall prone to significant wear with wear-resistni liners. The liners are generally sacrificial in nature, so that even though they are wear resistant they do require replacement from time to time. One such lining system utilises microledge-lined impact plates on the area of the chute most proned to wear, with the remainder of the chute being lined with a complex array 25 of bolt-on microledges and modular liner plates, The liner plates incorporate wear bars which can only be replaced by lifting the liner plates away from the chute, and either cutting the worn liner bars by way of an oxy-cutting process and then -2 replacing the worn liner bars, or alternatively replacing the whole liner plate. Such a procedure is time consuming and laborious, particularly as lifting equipment is required owing to the weight of the impact plates. Furthermore, the chutes can be a confined environment in which it can be difficult to work. Furthermore, particulate material entering the transfer chute can in certain circumstance accumulate on parts of the chute, with the accumulated material eventually causing choking within the transfer chute. The choking can interrupt or impede the rate of transfer of the particulate material. It is against this background, and the problems and difficulties associated therewith, that the present invention has been developed. Disclosure of the Invention The present invention provides a barrier system for material projected along a trajectory path, the barrier system comprising a first barrier curtain adapted to be located in the trajectory path, the first barrier curtain compromising an array of elongate flexible curtain elements suspended one adjacent another, wherein the curtain elements which from the first barrier curtain each comprise an elongate flexible element onto which a plurality of wear resistant elements are threaded. The barrier system may further comprise a second barrier curtain spaced rearwardly of the first barrier curtain so as to be down stream of the first barrier curtain with respect to the direction of travel of particulate material along the trajectory path. The second barrier curtain may compromise a flexible panel structure. Conveniently, the second barrier curtain comprises wear resistant rubber sheeting. The surface of the wear resistant rubber sheeting facing the trajectory path may be at least partially covered with wear resistant plates such as wear resistant ceramic tiles. Preferably, the second barrier curtain is suspended in position.

-3 Each wear resistant element may comprise a body having a hole to permit threading of the wear resistant element onto the elongate flexible element. Preferably, the hole in the body provides a clearance fit between the body and the elongate flexible element onto which it is threaded so as to allow the body to rotate about the elongate flexible element. The body of each wear resistant element may comprise a disc portion and an integral spacer portion, with the hole extending through the disc portion and the spacer portion. With this arrangement, a plurality of the wear resistant elements can be threaded onto each chain or other elongate flexible element, with the spacer portion of one wear resistant element contacting the disc portion of an adjacent wear resistant element such that there is a stack of wear resistant elements supported on the elongate flexible element with the various disc portions being separated one from another by the respective spacer portions therebetween. The spacings between adjacent disc portions provides gaps onto which particulate material may accumulate. The accumulated material may serve to shield part of the flexible curtain element from the aggressive effects of particulate material impacting upon the first barrier curtain. The curtain elements which form the best barrier curtain may be spaced one relative to another. The spacing between neighboring curtain elements in the array may allow some of the smaller sized fractions of particulate material impacting upon the first barrier curtain. The curtain elements forming the first curtain may be suspended from an elastic suspension system which permits some elastic movement of the curtain elements -4 in a vertical direction. The suspension system may comprise a rubber block incorporated in a mounting arrangement from which the chain or other elongate flexible element is suspended. The various curtain elements forming the first barrier curtain may be arranged -in 5 an arcuate array so as to present a concave face to oncoming particulate material travelling along the trajectory path. Similarly, the second barrier curtain may be arranged in an arcuate formation so as to similarly present a concave face to the trajectory path. The arcuate arrangement of the first and second barrier curtains assists in 10 preventing splattering of particulate material sideways and also serves to focus particulate material which has impacted upon the respective barrier curtains into a band from which it can fall downwardly along a narrow path towards the outlet of the chute. Typically, the barrier system according to the invention is used in association with 15 a chute (such as a head chute or a transfer chute) in a materials conveyor system where particulate material is discharged from a conveyor into the chute. in such a case, the barrier system is installed within the chute in the trajectory path of particulate material entering the chute. T h e barrier system may serve to shield the walls of the chute from being aggressively impacted by, the entering particulate 20 material. Furthermore, the barrier system may serve to absorb some of the kinetic energy of the particulate material, ensuring that the particulate material travels less aggressively to the outlet of the chute. The present invention also provides a materials conveyor system having a chute into which material is, in use, discharged along a trajectory path, and a barrier 25 system, as set forth hereinbefore, is installed in the trajectory path. JIi Brief Description of the Drawings The invention will be better understood by reference to the following description of one specific embodiment thereof as shown in the accompanying drawings in which: 5 Figure 1 is a schematic side elevational view of a barrier system according to the embodiment installed in the head chute for a belt conveyor; Figure 2 is a view similar to Figure 1, with the exception that the barrier system is shown in operation protecting the head chute from the aggressive effects of particulate material being delivered into the head chute from the belt conveyor; 10 Figure 3 is a plan view of the barrier system installed within the head chute; Figure 4 is a front elevational view of the barrier system showing in particular a first barrier curtain; Figure 5 is a perspective view of a wear resistant element forming part of the first barrier curtain, with part of the wear resistant element cut-away. to reveal the 15 cross-sectional profile thereof; Figure 6 is a schematic fragmentary view of a curtain element which along with similar curtain elements, forms the first barrier curtain; and Figure 7 is a side elevational view of one of the curtain elements and a suspension system from which the curtain element is suspended. 20 Best Mode(s) for Carrying Out the Invention The embodiment shown in the drawings is directed to a barrier system 10 for the head chute 11 at a transfer station of a conveyor system incorporating- a belt conveyor 13. The belt conveyor 13 comprises an endless belt 15 passing around end pulleys 17, only one of which is shown in the drawings. The belt 15 conveys 25 particulate material and discharges it into the head chute 11. In the drawings, the -6 particulate material is depicted schematically by hatching and is identified generally by reference numeral 19. The particulate material 19 discharges from the' belt conveyor 13 along a trajectory path 21 which is directed towards a rear wall 23 of the head chute 11 The barrier system 10 according to the embodiment 5 is positioned within the trajectory path 21 in front of the rear wall 23 to shield the rear wall 23 from the aggressive effects of impacting particulate material The barrier system 10 comprises a first barrier curtain 25, and a second barrier curtain 27 which is spaced from the first barrier curtain 25 in the downstream direction- of the trajectory path 21, as best seen in Figures 1, 2 and 3 of the 10 drawings. The first and second barrier curtains 25, 27 are suspended within the head chute 11 from a suspension system 29. The first barrier curtain 25 comprises a plurality of curtain elements 31 positioned in an array in side-by-side relationship. 15 The curtain elements 31 are positioned in an arcuate array, as best seen in Figure 3 of the drawings, such that the first barrier certain 25 presents a concave face 33 to oncoming particulate material discharging from the belt conveyor 13 along the trajectory path 2.1. Similarly, the second curtain barrier 27 is also arranged in an arcuate formation, also as best seen in Figure 3 of the drawings. 20 The curtain elements 31 are positioned in spaced apart relationship in the array such that a gap 37 exists between neighbouring elements, as best seen in Figure 4 of the drawings. Each curtain element 31 comprises an elongate flexible element 41 which in this embodiment is in the form of a chain. Each curtain element 31 further comprises 25 a plurality of wear resistant elements 43 threaded onto the chain 41. The wear-resistant elements 43 are assembled in a stack 45 on the chain 41, with the stack 45 resting on a stop 47 provided at the bottom end of the chain 41.

-7-. The top end of the chain 41 is detachably connected to the suspension system 29, as will be described in more detail later. Each wear resistant element 43 comprises a body 51 formed of wear resistant material. The body 51 comprises a disc portion 53 and a spacer portion 55 5 formed integrally with each other. A central hole 57 extends through the disc portion 53 and the spacer portion 55 to receive the chain 41 onto which the body 51 is threaded. When the wear resistant elements 43 are threaded onto the respective chain 41 to ( form one of the curtain elements 31, the spacer portion 55 of each element 43 10 (apart from the lowermost element in the stack 45) rests on the disc portion 53 of the particular element 43 below it, In this way, the disc portions 53 of the various elements 43 in the stack 45 are spaced apart one from another along the length of the stack 45. The spacing between the various disc portions 53 provides gaps 55 between neighbouring elements 43 into which particulate material can 15 accumulate, as illustrated in Figure 6 of the drawings. The accumulated particulate material 19a serves to assist in shielding the curtain element 31 to some extent from the impact in particulate material and so lessens the aggressive effects of the impact in particulate material on the curtain element A particular feature of the primary curtain 25 is that each chain 41 is entirely 20 protected from the aggressive effects of the particulate material by virtue of the stacks of wear resistant elements. The end face 58 of each disc portion 53 which is opposite the spacer portion 55 is profiled so as to taper inwardly, as best seen in Figure 6 of the drawings. With this arrangement, the size of the gap 55 between adjacent disc portions 53 25 increases in the inward direction. This provides the gap 55 with a somewhat of a wedge configuration with the narrower end of the wedge outermost. With this arrangement, particulate material 19a which is received within the gap 55 is trapped within the gap rather than from simply spilling out of the gap.

-8 Each chain 41 is connected at its upper end to the suspension system 29 by way of a safety hook 61 which permits the chain (together with the wear resistant elements 43 threaded thereon) to be removed from the suspension system 29. A lifting link 63 is incorporated between the safety hook 61 and the upper end of the 5 chain 41. The lfting link 63 is adapted to receive a lifting hook or other attachment component of a lifting sling for ease of handling of the curtain element The suspension system 29 incorporates a link 65 to which the safety hook 61 is adapted to be connected. A link 65 is a swivel link incorporated to allow the chain 10 41 to rotate freely. The link 65 is connected to a threaded suspension rod 67 which extends through an elastic block 69. The elastic block 69 rests on a cross member 73. With this arrangement, the- curtain element 31 is suspended from the cross member 73 through the elastic block 69. The elastic block 69 provides some damping of impacting forces striking the curtain element and allows limited 15 elastic vertical movement of the curtain element. The-second barrier curtain 27 is also suspended from the suspension system 29. The second barrier curtain 27 comprises rubber sheeting 71 with wear resistant plates such as ceramic tiles 73 mounted on the face of the rubber sheeting 71 exposed to the trajectory path 21. The rubber sheeting 7 1 is suspended between 20 two mounting plates 75 which- are curved along their length in a profile corresponding to the desired arcuate profile of the second barrier curtain 27. One of the plates 75 incorporates lugs 77 which are hooked onto the suspension system 29. More particularly, the suspension system 29 incorporates several rearwardly extending mounting webs 81 onto which the lugs 77 can be hooked. 25 The webs 81 incorporate a series of spaced recesses 83 into a selected one of which each lug 77 can be inserted. The provision of several recesses 83 in each web 81 provide a mechanism by which the spacing between the first and second barrier curtains 25, 27 can be selectively varied.

The lugs 77 also provide a convenient means by which the second barrier curtain 27 car be connected to a lifting sling or other lifting arrangement for installation and removal of the second barrier curtain. In operation, particulate material discharging into the head. chute 11 from the belt 5 conveyor 17 along the trajectory path 21 impacts upon the barrier system 10 according to the embodiment. The impacting particulate material may cause the first barrier curtain 25 and the second barrier curtain 27 to deflect rearwardly, as illustrated in Figure 2 of the drawings. Any impacting material which is not stopped by the first barrier curtain 25 passes between the curtain elements 31 10 and travels towards the second barrier curtain 27. Because of the arcuate profile of each of the barrier curtains, the impacting particulate material is focused towards a narrow band which falls downwardly from the barrier curtains 25, 27. The larger sized material fractions which do not pass through the.first barrier curtain 25 will fall almost vertically into the discharge section of the head chute 11 15 at relatively low velocities because of the material energy absorbed by the flexible structure of the first curtain barrier 25. The smaller sized fractions of material passing through the first curtain barrier 25 have a velocity greatly reduced by the initial impact with the first curtain barrier 25'. These particles will form a slow moving bed of material in the space between'the first and second curtain barriers 20 25, 27 vhich will fall downwardly in a far less aggressive manner. The result of the material flow pattern is such that the overall material velocities which approach the exit part of the head chute 11 are greatly reduced compared to conventional arrangements. The barrier curtains 25, 27 thus protect the rear wall 23 of head chute 11 from the 25 aggressive effects of the discharging particulate material without the need to install wear resistant plates on that wall. A particular feature of the present embodiment is that the curtain elements 31 can be repaired and replaced individually without requiring removal of the entire barrier system 10. Furthermore, the second barrier curtain 27 can be removed -10 and replaced independently of the first barrier curtain 25, if desired. Each curtain element 31 of the first barrier curtain 25, as well as-the second barrier curtain 27, can be easily removed from the head chute 11 using an appropriate lifting mechanism such as a sling. 5 Because the wear resistant elements 43 are threaded onto their respective chain -41 through the holes 57 which provide a clearance fit between the wear resistant element 43 and the chain 41, it is possible for the:wear resistant element 43 to progressively rotate with respect to the chain under the influence of forces imparted to it by the impacting particulate material. This rotation has the effect of 10 spreading wear around the wear resistant element, so extending the useful wear life of the wear resistant elements 43. The embodiment is particularly useful in cases where the conveyor system is handling sticky material. Because of the flexible construction of the first barrier curtain 25, the accumulation of the sticky material on the first barrier curtain is 15 prevented. The second barrier curtain 27 has a smooth, hard flexible surface which also resists accumulation of the sticky material. Furthermore, as material flow rates along the conveyor vary or stop, the material momentum forces which cause deflection of the first and second barrier curtains 25, 27 will vary, so causing .the barrier curtains to flex forwardly and rearwardly with respect to the 20 trajectory path. This flexing movement of the barrier curtains 25, 27 can assist in dislodging any accumulated material from the barrier curtains. From the foregoing; it is evident that the present invention provides a simple, yet highly effective, arrangement for providing some control over flow of particulate material in a chute of a materials conveyor system and for providing protection to 25 the exposed surfaces of the chute without the need to install wear protection elements on those surfaces of the chute, In this way, the significant costs and difficulties associated with installation and maintenance of wear protection plates and other elements on the surfaces of the chute are avoided The present invention allows for a reduction in the overall height of transfer 30 stations and a reduction in the length of conveyor sections in conveyor systems.

The present invention is capable of handling any particulate material, in particular particle sizes from about 350 mm to powder. The present invention is advantageous when installed in chutes of materials conveyor systems as it can accommodate sticky materials and materials with a 5 relatively high moisture content without choking within the chute. Furthermore, feed material degradation rates and noise levels will generally be lower for chutes fitted with a barrier system according to the invention in comparison to conventional chutes. Additionally, a chute fitted with a barrier system according to the invention adjusts 10 automatically to material flow rate variations and ensures satisfactory tracking of a discharge conveyor receiving material via the chute. it should, however, be appreciated that the scope of the invention is not limited to the scope of the embodiment described. in particular, it should be understood that the barrier system according to the invention may have applications in any 15 area where it is necessary to protect a surface from an aggressive flow of material or materials. Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of ?0 any other integer or group of integers.

Claims

1. A barrier system for material projected along a trajectory path, the barrier system comprising a first barrier curtain adapted to be located in the trajectory path, the first barrier curtain comprising an array of elongate flexible curtain elements suspended one adjacent another, wherein the curtain elements forming the first barrier curtain each comprise an elongate flexible element onto which a plurality of wear resistant elements are threaded.

2. The barrier system according to claim 1 further comprising a second barrier curtain spaced rearwardly of the first barrier curtain so as to be down stream of the first barrier curtain with respect to the direction of travel of particulate material along the trajectory path.

3. The barrier system according to claim 2 wherein the second barrier curtain comprises a flexible panel structure.

4. The barrier system according to claim 2 or 3 wherein the second barrier curtain comprises wear resistant rubber sheeting.

5. The barrier system according to claim 4 wherein the surface of the wear resistant rubber sheeting facing the trajectory path is at least partially covered with wear resistant plates.

6. The barrier system according to claim 5 wherein the wear resistant plates are in form of wear resistant ceramic tiles.

7. The barrier system according to claim 2 to 6 wherein the second barrier curtain is suspended in position.

8. The barrier system according to claims 2 to 7 wherein the second barrier curtain is suspended such that it may be positioned at different distances from the first curtain. -13

9. The barrier system according to any one of the preceding claims wherein the elongate flexible element comprises a chain.

10. The barrier system according to any one of the preceding claims wherein each wear resistant element comprises a body having a hole to permit threading of the wear resistant element onto the elongate flexible element.

11. The barrier system according to claim 10 wherein the hole in the body provides a clearance fit between the body and the elongate flexible element onto which it is threaded so as to allow the body to rotate about the elongate flexible element.

12. The barrier system according to claim 10 wherein the body of each wear resistant element comprises a disc portion and an integral spacer portion, with the hole extending through the disc portion and the spacer portion, whereby a plurality of the wear resistant elements can be threaded onto each elongate flexible element, with the spacer portion of one wear resistant element contacting the disc portion of an adjacent wear resistant element such that there is a stack of wear resistant elements supported on the elongate flexible elements with the various disc portions being separated one from another by the respective spacer portions therebetween.

13. The barrier system according to claim 12 wherein the spacings between adjacent disc portions provides gaps into which particulate material accumulates such that the accumulated material shields part of the flexible curtain element from the aggressive effects of particulate material impacting upon the first barrier curtain.

14. The barrier system according to any one of the preceding claims wherein the elongate flexible curtain elements providing the first barrier curtain are spaced one relative to another.

15. The barrier system according to any one of claims 2 to 14 wherein the spacing between neighboring curtain elements in the array is such that some -14 of the smaller sized fractions of particulate material impacting on the first curtain pass therethrough to the second barrier curtain.

16. The barrier system according to any one of the preceding claims wherein the curtain elements providing the first curtain are individually suspended from an elastic suspension system to permit some elastic movement of the curtain elements in a vertical direction.

17. The barrier system according to claim 16 wherein the suspension system comprises a rubber block from which each elongate flexible element is suspended.

18. The barrier system according to any one of the preceding claims wherein the various curtain elements forming the first barrier curtain are arranged in an arcuate array so as to present a concave face to oncoming particulate material travelling along the trajectory path.

19. The barrier system according to any one of claim 2 to 18 wherein the second barrier curtain is arranged in an arcuate formation so as to present a concave face to the trajectory path.

20. A barrier system according to any one of the preceding claims in combination with a chute in a material conveyor system, the barrier system being installed within the chute in the trajectory path of particulate material entering the chute.

21. A materials conveyor system having a chute into which material is, when in use, discharged along a trajectory path, and a barrier system, according to any one of claims 1 to 20, is installed within the chute in the trajectory path.

22. A barrier system as substantially herein described with reference to the drawings.

23. A barrier system in combination with a chute as substantially herein described with reference to the drawings. -15

24. A materials conveyor system as substantially herein described with reference to the drawings.