AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention title: TRANSPORT HOPPER AND FABRICATING METHOD THEREFOR The following statement is a full description of this invention, including the best method of performing it known to us: 2 TRANSPORT HOPPER AND FABRICATING METHOD THEREFOR Field of the Invention The present inventions relates to hoppers and methods for constructing hoppers. 5 These hoppers may be applied to mining trucks and aggregate trucks in general. The invention also relates to train freight cars and to methods of constructing train freight cars. Background to the Invention Hoppers for mining trucks are known, as are aggregate trucks in general, and train 10 freight cars of different designs and shapes that are used to transport materials or mineral ore of differing granulometries, particle sizes and densities, which causes the volume or tonnage to differ depending of the latter parameter as regards an identical volume. Hoppers are generally made from structural steel and, in some cases, anti-abrasive steels, depending on the application and loading system. This latter point differs from 15 each site, giving a better or worse condition with respect to the loading of the material. Sometime the material is loaded through a chute, which is a rather gradual and controlled loading. Other times the loading is an impact loading, such as for example in the case of a front loader wherein the load projects over by the sides of the hopper and the load drops instantly on the loading area or on a side of the hopper. Sometimes the operator loses 20 sight of the equipment or load. In all loading cases, the welds that are used to join sides and floor or front and floor become seriously damaged by various means. It is advantageous, for all of the aforementioned conditions, to have stronger hoppers given current conditions and trends in the mining industry, which prefers larger equipment and greater loading capacity, with greater equipment maintenance availability. 25 To achieve this effect, larger and stronger hoppers are required. A larger number of structures would facilitate making the hoppers stronger and/or thicker in order to absorb impacts, in addition to increasing availability as a result of the wearing of the plates that are in contact with the material and aggregate's sliding upon emptying. Known materials and methods of construction make the hopper and components 30 sturdier, increasing its own weight along with a consequent decrease in the material transported, depleting from the equipment (trucks or freight cars) loading capacity. On the other hand, if a lighter hopper is made, sacrificing the thickness and materials of its structure, the frequency of its maintenance or replacements will have to be increased to 3 cope with the decreased equipment availability due to frequent maintenance. Users seek a balance of a hopper being able to resist loads and impacts and abrasion, and, in turn, light for its availability for corrective maintenance to be greater. Summary of the Invention 5 In accordance with a broad aspect of the present invention there is provided a hopper suitable for use on a mining truck, the hopper comprising selected regions strengthened by folded elements. In accordance with a first aspect of the present invention there is provided a mining truck hopper, comprising: 10 a floor having a front and a rear; first and second sidewalls extending upwardly from the floor, the first and second sidewalls having outside surfaces; a front wall extending upwardly from the front of the floor and extending between the first and second sidewalls; 15 a shield wall extending forwardly from the front wall in a direction away from the rear of the floor; the floor and the first and second sidewalls being joined by folds and there being no welds between the floor and the first and second sidewalls; the shield wall including a shield fold that extends transversely to the first 20 and second sidewalls, and the shield fold being located forward of the front wall and rearward of a front end of the shield wall; the front wall including a plurality of folds that extend transversely to the first and second sidewalls and parallel to the shield fold; the floor, the first and second sidewalls, the front wall, and the shield wall 25 being made of steel; and the first and second sidewalls being supported by two folded beams on the outside surfaces of the first and second sidewalls. In accordance with a second aspect of the present invention there is provided a hopper structure configured to transport mining material, comprising: 30 a floor having a front and rear; first and second sidewalls extending upwardly from the floor, the first and second sidewalls having outside surfaces; a front wall extending upwardly from the front of the floor and extending between the first and second sidewalls; 3A a shield wall extending forwardly from the front wall in a direction away from the rear of the floor; the floor and the first and second sidewalls being joined by folds and there being no welds between the floor and the first and second sidewalls; 5 the shield wall including a shield fold that extends transversely to the first and second sidewalls, and the shield fold being located forward of the front wall and rearward of a front end of the shield wall; the front wall including a plurality of folds that extend transversely to the first and second sidewalls and parallel to the shield fold; 10 the floor, the first and second sidewalls, the front wall, and the shield wall being made of steel having a hardness of at least 200 Brinell, a resistance of at least 300 MPa, and a thickness of at least 6 mm; and the first and second sidewalls being supported by two folded beams on the outside surfaces of the first and second sidewalls. 15 Preferably the folded elements include a front or brow member or overhead strengthening member disposed at region of the hopper above the cabin of the mining truck. Preferably the folded elements further include a shield member in use disposed behind the cabin of the mining truck. Preferably there are several spaced apart folds in 20 the shield member. Preferably the folded elements include side members. Preferably the side members include plates. Preferably the side members include reinforcing structural beams so that plates may attach to the reinforcing structural beams. Preferably the folded elements include floor members. Preferably the folded 25 elements include floor members and side members integrated to reduce the amount of welding on the floor. Preferred embodiments of the present invention are based on the use of state of the art or cutting edge technological elements in order to fulfil the objectives required by current market, achieving resistance to greater loading capacity without increasing its 30 weight from structuring the unit or lengthen its useful life due to floor abrasion to meet availability as required by the customer. In accordance with a second aspect of the present invention there is provided a method of constructing a hopper for use in a mining truck, the method including affixing folded elements to selected regions of the hopper.
3B In accordance with a third aspect of the present invention there is provided a rail wagon including a material transport section comprising folded elements at selected regions. 5 In accordance with a fourth aspect of the present invention there is provided a mining truck including a hopper comprising folded elements at selected regions.
4 In order to facilitate the resistance and availability requirements there presently exist special steels having greater tensile strength, from 300 MPa to 700 MPa tensile strength, depending on the type and origin. Preferred embodiments of the present invention utilise steels having better mechanical properties, a structure being able to have 5 equal or greater tensile strength without having to increase the thickness of the materials, since their densities do not vary much, in addition to making a design with computer design methods and tools currently available in order to simplify the structure, said structure being virtually analyzed fast and safely, which allows the making of steel folds at critical areas of the hopper which makes it stronger. At the same time, in order for these 10 folds to be made, more powerful and high-precision equipment is required, which forces us to use large folding-capacity technology having CNC's (Computer Numerical Controls) given the size of the precision pieces and the steels also require more power to fold due to their special properties. Preferably, in order to prevent abrasion wear, abrasion-resistant steels having 15 hardness indices spanning from 200 current Brinell to 450 and/or 500, or over, being able to considerably increase the useful life against abrasion, but the tensile strength of which rises from about 800 Mpa to 1,400 Mpa, and over, are provided, which requires, moreover, the use of more robust equipment than traditionally, as was stated above. This allows to provide a highly strong, highly available product for production, but having a low 20 structural weight, thus allowing to transport larger loads and reduce the cost of fuel consumption, which, in large pieces of equipment, is a factor of considerable relevance. Traditional manufacture of hoppers is based on very heavy structures having standards beams. In some cases, special materials are used depending on the design, but they do not comply with the abovementioned objectives. As regards light hoppers, 25 their weight is smaller in order not to reduce the truck's capacity, but have a shorter useful life due to shocks and/or abrasion, which forces the equipment to remain idle for more frequent maintenance. As for applications of anti-abrasive steels, they are applied in their natural state as unfolded plates as a result of their high stength properties, and because making them with 30 standard methods is very difficult. Preferred embodiments of the present invention include special handling when applying the materials, in particular the cutting-edge steels described herein, since the challenges faced to fold the design, including the sizes of the components, and the folds that are located at particular and strategic places. These challenges are alleviated by the 35 assistance of computer simulation tools so that the precise support for the hopper may be 5 facilitated. This is facilitated by supplementing and adapting software related to 3D studies, together with finite element analysis upon developing each part, and later the general analysis of the assembly, simulating different typical working conditions on upward and downward slope, side inclinations, etc. 5 Preferably the present invention provides the floor elements comprising anti abrasive, side folds that reduce or eliminate welding at joints and floor, which improves mechanical resistance and alleviates stress arising from heat concentration upon welding. Preferably, at the sides, reinforcement on several beams is simplified by two larger joining beams that keep the structure substantially rigid. 10 Preferably, at the front of the hopper, where the impact of the load and of the loading cone joins the cabin, this plate is folded and its form and size reinforces its structure by replacing outer reinforcement beams, decreasing the weight of the hopper and holding a greater additional load of material. The direction of the folding or of the folds may be transverse or longitudinal, or both, and it will depend on the design or load 15 conditions. Preferred features of the hopper shield are set out in the paragraph below. This element, in general, is not analyzed in detail, only as regards safety considerations related to the protection the truck cabin against excesses or spills hood of load from the cone. In this case, in addition, the protective element was folded in order to have the necessary 20 resistance. In this case the fold is transverse, but it may take a longitudinal folding condition, or both, thus eliminating several reinforcement beams and especially being limited to the load cone with a retaining effect so that the material does not pass that point towards the truck's front area, thus changing the load's center of gravity, varying the distribution of the load between truck axles, thus affecting tire wear, among other effects 25 on the truck's structure. In addition, using fewer beams and simplifying the design by the folded large-piece system makes its compact structure contain stress concentration points, helping its performance as a structural assembly subjected to cyclical stress, minimizing the likelihood of specific failures. 30 The supplement of each one of the studies on each hopper, both in the system and in the database, allows us to adapt the design to the needs of each customer as for manufacture and design, being able to make improvements in accordance with operational conditions at each site, that is, the density of the material is low, with respect to the one considered in the initial study, the hopper's volume may be increased and/or 6 the thickness of the materials may be reduced, that is, lower the safety factors where indicated and allowed by the analysis without affecting a quality and reliable product. The direction and number of the folds in each part of the hopper or of the freight car is determined according to the structure, load parameters and study of the components' 5 finite elements. Brief Description of the Drawings Preferred embodiments of the present invention will be hereinafter described, for the purposes of clarity and increasing understanding, with reference to the following 10 drawings, and in those drawings: Figure 1 shows an isometric view of a hopper in accordance with a preferred embodiment of the present invention, highlighting a shield fold for increasing strength of the shield and for resisting movement of transported material towards the equipment's front area; 15 Figure 2 shows a rear view of the hopper of Figure 1, highlighting the joining folds between the equipment's floor and side; and Figure 3 shows a side elevation view of the hopper of Figure 1, highlighting the joining of two folded beams, in form and size, which, in their layout, replace several beams having the same purpose. 20 Detailed Description of a Preferred Embodiment A preferred embodiment of the present invention is a hopper shown in Figure 1 which incorporates a simplified number of pieces to form a heavy (from 100 to 400 ton) mining truck hopper. The preferred hopper design shown in the Figure advantageously 25 incorporates strategic simplifications in its manufacture, a reduced number of components and the application of special steels, providing a hopper having greater resistance to impacts as a result of its design containing strategic folds, greater abrasion resistance from the use of special steels. It is also lighter because its design eliminates structural beams, making it an advantageous hopper for facilitating at least some of the objectives 30 hereindescribed, achieving a balance between the increased strength and reduced weight of the hopper. Advantageously, this provides several advantages: 1. lower costs as a result of its longer useful life; 7 2. improved shield, which allows the loading cone not to move towards the cabin, keeping load center, deceasing tire wear and, more importantly, increasing the truck operator's safety. Another preferred embodiment may be applied to small tonnage train and truck 5 cars, because the design is fully adaptable to any size and shape as desired, since the preferred designs are computer analyzed, proving the effectiveness of each one of the preferred embodiments. As is shown in Figure 1, zone A, being a shield wall 10 having a shield fold 12 for resisting and retaining the material moving towards the equipment's front zone is 10 identified. The shield fold 12 extends from one side of the shield wall 10 to the opposite side of the shield wall 10 transverse to the sidewalls, and the shield fold 12 is located forward of the front wall and rearward of a front end of the shield wall. Further shown in Figure 1, Zone B, a folded front piece 14, improves body resistance and eliminates structural pieces, prevents this zone from buckling due to its 15 folded form, namely a plurality of folds 16. The direction of the folding may be transverse (as shown in the figure) longitudinal, and/or both options, as required by the loading to be applied. Zones C and D, in Figure 2, show joining folds between the equipment's floor 18 and side walls 20. As for the fold, it may be folded along with the load flow if required by 20 the study. In Figure 3, point E shows the joining of two folded beams 22, 24 in shape and size that, in their layout, replace several beams fulfilling the same purpose, structuring the assembly's side portion. The side plates may be folded vertically or in the direction of the flow, as required. 25 Throughout this 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 element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. 30 Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the 7A field relevant to the present invention as it existed in Australia or anywhere in the world before the priority date of each claim of this specification.