WO2020087183A1

WO2020087183A1 - Cast feeder pans, methods of casting same and uses therefore

Info

Publication number: WO2020087183A1
Application number: PCT/CA2019/051555
Authority: WO
Inventors: Alex Tutschek; Brad TUTSCHEK; Mihai Corabian; Dragan Bogojevic
Original assignee: Boundary Equipment Co. Ltd.
Priority date: 2018-11-02
Filing date: 2019-11-01
Publication date: 2020-05-07
Also published as: CA3116134A1

Abstract

Disclosed herein are feeder pans for use in forming a continuous feeder pan conveyor for transporting a bulk material. The feeder pan comprises a plate defined by a longitudinal nose edge and an opposed longitudinal tail edge and a first end opposed by a second end spanning the nose edge and the tail edge, and having a top side for supporting a bulk material and a bottom side opposed the top side; an at least one pan wing extending from the top side at or near a first end of the plate; a tail flange extending from the longitudinal tail edge; a nose gusset and a tail gusset each extending longitudinally from the bottom side of the plate from at or near the first end to at or near the second end; and a plurality of cross gussets spanning from the nose gusset to the tail gusset defining corresponding lower cavities. The feeder pan may be produced using a casting method.

Description

CAST FEEDER PANS, METHODS OF CASTING SAME AND USES THEREFORE

RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application Serial No.: 62/755,004 filed November 2, 2018, the entire contents of which is hereby incorporated by reference.

FIELD OF INVENTION

[0002] The present invention relates to feeder pans and related methods of manufacturing, including casting, and uses thereof for transporting bulk material. BACKGROUND OF THE INVENTION

[0003] Apron feeders are often used for heavy duty material handling processing operations, such as material handling in mine sites. Raw material is dumped from trucks, such as haul trucks, on to apron feeders and carried further in the production line. In oilfield applications, apron feeders may be larger in size to handle heavy material loads. Apron feeders may comprise a drive shaft with sprockets, idler shaft with tension idlers, support and return rollers, track chains, impact rails, and feeder pans mounted on the track chain links. When feeder pans are mounted on the track chain, they form a continuous belt that carries material over a set distance. During rotation around the sprocket or idler end, the plates open up along a long, or longitudinal, edge to evacuate the material. [0004] In the current state of the art, feeder pans are often manufactured by a fabrication process. This fabrication process may include cutting plate material to size, and welding various parts, such as wing plates, bottom support gussets, and a tail plate to the plate material. One drawback to this process is the creation of stress concentration points located near the welds. Stress concentration points may be created by heat affected zones combined with a rough weld surface and/or weld undercuts. Feeder pans may also experience deflection or vibration during periods of significant load. These factors can significantly reduce the lifespan of feeder pans, particularly in the oil sands or particularly when used in environments that necessitate the transport of heavy loads. Fabricated feeder pans on apron loaders will often bend, break and/or crack when used in an oilfield application. Often the bending, breaking and/or cracking occurs near or at weld points, such as at pan wings and tail flanges and at the stress concentration points. Damage, sustained from use, at the welds and stress concentration points generally results in high maintenance costs as the conveyor must be shut down and the component either fixed or replaced.

[0005] There exists a need in the art for a feeder pan that resists, reduces or mitigates deflection, vibration and/or cracking while allowing for the transport of large material loads.

SUMMARY OF THE INVENTION

[0006] The present invention relates to feeder pans for use in forming a continuous feeder pan conveyor for transporting a bulk material. Also disclosed herein are methods of

manufacturing cast feeder pans.

[0007] Disclosed herein are cast feeder pans comprising a plate section defined by a longitudinal nose edge and an opposed longitudinal tail edge and a first end opposed by a second end spanning the nose edge and the tail edge. The plate section further comprises a top side for supporting a bulk material and a bottom side opposed the top side. Near or at one or each end of the plate section, the feeder pan comprises a pan wing extending from the top side of the plate. The pan wing acts as a retaining wall to prevent or reduce bulk material on the top face of the plate from falling off the ends of sides of the feeder pan. A longitudinal flange extends along or from the longitudinal tail edge and is referred to as a tail flange. On the bottom side of the plate section, to increase strength, rigidity, and/or torsional strength, a number of gussets extend downwardly. For example, a nose gusset and a tail gusset each extend from the bottom side of the plate longitudinally from at or near the first end to at or near the second end, and a plurality of cross gussets span from the nose gusset to the tail gusset and define corresponding lower cavities.

[0008] According to an aspect of the present invention there is provided at least one central gusset that extends longitudinally between the nose gusset and the tail gusset. In some embodiments, the feeder pan comprises at least one wear pad on the top face of the plate and is positioned in areas of higher wear. For example, in further embodiments, the at least one wear pad is mounted adjacent to the at least one pan wing. In some embodiments, the top face of the plate comprises an upper cavity or recess adapted to receive or accommodate the wear pad. Some embodiments may comprise the wear pad fastened to the plate by fasteners, where the fasteners pass through apertures in the plate and the fasteners are secured within the lower cavity thereby at least partially shielding the fastener on at least the bottom side of the plate section.

[0009] In some embodiments, the wear pad comprises manganese steel. According to some aspects of some embodiments, the nose edge of the plate section comprises a nose riser extending inward from the nose edge, the tail edge of the plate comprises a tail riser extending inward from the tail edge, and a tail flange is connected to the tail edge of the plate section at a base of the tail riser. In some embodiments, the nose riser and the tail flange are adapted to form a continuous longitudinal seal with a corresponding tail flange and nose riser, respectively, of an adjacent feeder pan in the continuous conveyor. Further embodiments may comprise nose reinforcing ribs positioned on the bottom side of the plate that extend between the nose edge and the nose gusset; and tail reinforcing ribs positioned on the bottom side of the plate that extend between the tail edge and/or tail flange and the tail gusset. The feeder pan may comprise manganese steel. Some further embodiments comprise a grouser extending longitudinally from the top surface of the plate. The feeder pan may be of any suitable length including for example between about ten feet and about twenty feet in length. Apron feeders may comprise any embodiment of the feeder pan.

[0010] Feeder pans of the present invention may be produced by casting, traditional manufacturing or by using a hybrid of casting and traditional assembly such as but not limited to bolting or welding.

[0011] In one embodiment, the present invention provides a feeder pan for use in forming a continuous feeder pan conveyor for transporting a bulk material, the feeder pan comprising: a plate defined by a longitudinal nose edge and an opposed longitudinal tail edge and a first end opposed by a second end spanning the nose edge and the tail edge, and having a top side for supporting a bulk material and a bottom side opposed the top side; an at least one pan wing extending from the top side at or near a first end of the plate; a tail flange extending from the longitudinal tail edge; a nose gusset and a tail gusset each extending longitudinally from the bottom side of the plate from at or near the first end to at or near the second end; and a plurality of cross gussets spanning from the nose gusset to the tail gusset defining corresponding lower cavities.

[0012] In a further embodiment of the feeder pan or pans outlined above, the feeder pan further comprises an at least one central gusset that extends longitudinally between the nose gusset and the tail gusset.

[0013] In a further embodiment of the feeder pan or pans outlined above, the feeder pan further comprises at least one wear pad on the top face of the plate.

[0014] In a further embodiment of the feeder pan or pans outlined above, the at least one wear pad is mounted adjacent to the at least one pan wing. [0015] In a further embodiment of the feeder pan or pans outlined above, the top face of the plate comprises an upper cavity adapted to receive the wear pad.

[0016] In a further embodiment of the feeder pan or pans outlined above: the wear pad is fastened to the plate by fasteners; and the fasteners pass through apertures in the plate and the fasteners are secured within the lower cavity. [0017] In a further embodiment of the feeder pan or pans outlined above, the wear pad comprises manganese steel.

[0018] In a further embodiment of the feeder pan or pans outlined above: the nose edge of the plate comprising a nose riser extending inward from the nose edge; the tail edge of the plate comprises a tail riser extending inward from the tail edge; and the tail flange is connected to the tail edge of the plate at a base of the tail riser. [0019] In a further embodiment of the feeder pan or pans outlined above, the nose riser and the tail flange are adapted to form a continuous longitudinal seal with a corresponding tail flange and nose riser, respectively, of an adjacent feeder pan.

[0020] In a further embodiment of the feeder pan or pans outlined above, the feeder pan further comprises: nose reinforcing ribs positioned on the bottom side of the plate that extend between the nose edge and the nose gusset; and tail reinforcing ribs positioned on the bottom side of the plate that extend between the tail edge and/or tail flange and the tail gusset.

[0021] In a further embodiment of the feeder pan or pans outlined above, the feeder pan comprises manganese steel. [0022] In a further embodiment of the feeder pan or pans outlined above, the feeder pan further comprises a grouser extending longitudinally from the top surface of the plate.

[0023] In a further embodiment of the feeder pan or pans outlined above, the feeder pan is between about ten feet and about twenty feet in length.

[0024] In a yet further embodiment, the present invention provides for an apron feeder comprising a feeder pan as disclosed herein.

[0025] In a further embodiment of the feeder pan or pans outlined above, the feeder pan is formed by a casting process.

[0026] In a further embodiment of the feeder pan or pans outlined above, at least a portion of the feeder pan is formed by a casting process. [0027] Methods of manufacturing cast feeder pans are disclosed herein. In one embodiment, the method comprises: pouring heated material into a mold of the cast feeder pan, resting the material within the mold, removing the mold from the cast feeder pan, heat treating the cast feeder pan, and quenching the cast feeder pan with water. In some embodiments, the methods described are used to manufacture embodiments of cast feeder pans as described herein. In some embodiments, the cast is a sand cast. [0028] In one or more embodiments of the methods described herein, the method further comprises removing a gating system and columns from the casting after the mold is removed. In some embodiments, the resting step comprises resting between 1-1.5 hours. In one or more embodiments of the methods described herein, the method further comprises visually inspecting the cast feeder pan prior to heating.

[0029] In further embodiments of the method, heat treating comprises: 1) ramping up the temperature to 600°C with 200°C/ hour rate of increase; 2) holding the temperature at 600°C for 2 hours; 3) ramping up to 900°C with 200°C/hour rate; 4) holding at 900°C for 2 hours; 5) ramping up to l050°C with 200°C/hour rate; and 6) holding at l050°C for 6 hours.

Quenching with water may occur when the cast feeder pan is heated to l050°C. In these embodiments and others, quenching comprises maintaining the water at temperatures lower than 30°C prior to quenching.

[0030] In yet further embodiments, the method comprises heating the heated material to l500°C prior to pouring. The heated material may comprise manganese steel. In some embodiments, the method further comprises pressing the cast feeder pan after heat treating. In these embodiments and others, the cast feeder pan may be machined the cast feeder pan to remove or add casted or non-casted components., after quenching.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] These and other features of the invention will become more apparent from the following description in which reference is made to the appended non-limiting drawings wherein:

FIGETRE 1 shows an isometric view of one example of a feeder pan in accordance with an embodiment of the present invention;

FIGETRE 2 shows an exploded isometric view of the feeder pan of Fig. 1; FIGETRE 3 shows an isometric cross sectional view of a top side of the feeder pan of Fig. 1 allowing for gussets to be seen; FIGURE 4 shows an isometric view of a bottom side of the feeder pan of Fig. 1;

FIGURE 5 shows a close-up isometric view of a bottom side of the feeder pan of Fig. 1;

FIGURE 6 A shows an end view of the feeder pan of Fig. 1, with a further embodiment of the feeder pan with a grouser and fabricated feeder pans; FIGURE 6B shows a cross-sectional view taken along a longitudinal axis of the adjacent feeder pans of Fig. 6A;

FIGURE 7 shows an end view of an apron feeder with adjacent feeder pans of Fig. 1, a chain assembly and a drive sprocket;

FIGURE 8 shows an isometric view of the apron feeder of Fig. 7; and FIGURE 9 shows a schematic depicting a method of manufacturing a feeder pan, for example the feeder pan of Fig. 1.

DETAILED DESCRIPTION

[0032] One or more illustrative embodiments have been described by way of example with reference to Figures 1 to 8. It will be apparent to persons skilled in the art that a number of variations and modifications can be made without departing from the scope of the invention as defined in the claims. The illustrative embodiments described herein are for the purposes of illustrating aspects of the invention and are not intended to be limiting in any way. Any reference to an embodiment, example or aspect is intended to be a reference to a non-limiting embodiment, example or aspect of the invention. [0033] It will be appreciated that reference herein to a continuous conveyor or a continuous belt is interchangeable and is intended to capture any continuous apron feeder whether operated using a belt, chain or combination thereof.

[0034] Referring to Figs. 1 and 4, an embodiment of a feeder pan 10 is shown. The feeder pan 10 is manufactured to resist, reduce or mitigate bending and/or flexing during transport of heavy material loads. The feeder pans may be used in transporting bulk material such as bulk material at a mining operation, petrochemical operation, etc. The feeder pan 10 may comprise a plate 1, an at least one pan wing 24, a tail flange 26, a nose gusset 28, a tail gusset 30 and a plurality of cross gussets 32. Multiple feeder pans 10 are placed adjacent one another to form a continuous feeder pan conveyor when assembled, for example as shown in Fig. 8

[0035] Referring to Figs. 1, 2, 4 and 5, the plate 1 extends longitudinally across the feeder pan 10. The plate 1 may be defined by a longitudinal nose edge 12 and an opposed longitudinal tail edge 14. The first end 16 may extend between the nose edge 12 and the tail edge 14, and is opposed by a second end 18. The plate 10 may also be defined by a top side 20 that is suitable for supporting a bulk material, and a bottom side 22 opposed the top side 20 which includes a number of structural elements for increasing the strength of the feeder pan 10.

[0036] Referring to Figs. 1 and 6B, the feeder pan 10 may comprise a tail flange 26. The tail flange 26 may connect to the tail edge 14 of the plate 1. In some cases, the tail flange 26 is connected to the bottom side 22 directly and in other cases, the tail flange 26 may connect to a tail riser 42. In both embodiments, it can be said that the tail flange 26 connects directly or indirectly to the tail edge 14 of the plate 1. The tail flange 26 may be connected via cast molding to plate 1, or in some cases, the tail flange 26 is fastened to plate 1 via fasteners, such as bolts. In the event that the plate 1 is formed by casting and the tail flange 26 is bolted to the casting, this would be referred to as a hybrid cast. The tail flange 26 may contact adjacent, or neighbouring, feeder pans 10A when assembled as a continuous apron feeder. The tail flange 26 may be shaped to provide a surface 27 for contacting an adjacent pan 10 A. As will be discussed below in more detail, the tail flange 26 may be shaped to substantially form a seal with the adjacent feeder pan when in a generally flat orientation on the conveyor (as opposed to when the feeder pan is rotating around the ends of the belt such as the drive sprocket). In some cases, the tail flange 26 is comprised of a suitable material that resists wear from contact. A worn out or damaged tail flange 26 may be removed or replaced with a new tail flange 26 by any suitable method, such as removing the fasteners (not pictured) or by cutting off the tail flange 26. Tail flange 26 may be stepped to mate in a substantially sealing manner with the nose edge 12 of an adjacent feeder pan 10 A. The tail flange 26 may define a sharp tail edge, and may assist in material cleaning.

[0037] Referring to Figs. 6A and 6B, the feeder pan 10 may substantially form a seal with an adjacent feeder pan 10A when that section of the apron feeder is in a substantially flat or straight orientation, also referred to as the transport orientation. A seal between adjacent pans may act to prevent bulk material from falling between adjacent pans during operation of the belt. To form the seal, the nose edge 12 may comprise a nose riser 40 extending inward from the plate 1. The nose riser 40 may extend to contact a tail riser 42 extending inward from the tail edge 14 of an adjacent feeder pan 10. The tail flange 26 may be shaped to continuously contact and seal with the adjacent pan 10A while in use within a continuous belt when in the straight section. The surface 27 and the tail flange 26 may define a curvilinear shape in cross section. The nose riser 40 and the tail riser 42 may be adapted to provide continuous contact along face 41, surface 27 of nose riser 40 and the tail flange 26, respectively. The nose riser 40 and the face 41 may be shaped to mate with tail flange 26 and surface 27 while the large feeder pan is in motion while in use in a continuous belt. For example as shown in Figs. 7 and 8, the feeder pan 10 has a path of travel when in use in a continuous belt. The path of travel of the continuous belt of the feeder pans has straight and curved sections. The straight sections may be defined as sections during which material can be transported. Curved sections may be defined at each end of the belt around the sprocket or idler end. The path of travel of the pan 10 may include a curved section around at least part of the circumference of the drive sprocket 56 or idler end. In certain embodiments, the seal is maintained during travel around one or more curved sections, such as around sprocket 56.

[0038] Referring to Figs. 4 and 5, the feeder pan 10 may comprise structural elements on the bottom side 22 of the plate 1 for providing support to the feeder pan 10 and may act to resist damage caused by stress, such as torsion, shear, flex, and bending stress. Support may be provided by increasing the size or number of gussets at the areas of stress concentration.

These areas may include areas near the first and second ends 16, 18 of the plate 1. The feeder pan 10 may comprise gussets on the bottom side 22 of the plate 1 that reinforce plate 1 with respect to longitudinal flex, torsional flex, or both. Gussets may be implement to strengthen stress concentration area as desired. Gussets may be found on the top side 20, at or towards the ends 16, 18 of the plate 1, or at any suitable location to reinforce the plate 1. In some cases, the gussets form an interconnected web of gussets that act to reinforce the plate 1. The combination of longitudinal gussets and cross gussets may provide a double gusset structure. Gussets may be formed with the plate 1 during a casting process, or attached to plate 1 by appropriate means, such as welding. The feeder pan 10 may comprise one or more columns 64 that may be formed with other structures, such as cross gussets or longitudinal gussets. The column 64 may act to strengthen feeder pan 10 and assist in preventing flexing or other deleterious deformation. Column 64 may be formed as risers during the casting process and may be trimmed or cut down after the forms are removed.

[0039] As shown with reference to Figs. 4 and 5, in one embodiment the plate 1 may comprise longitudinal gussets, such as a nose gusset 28, a tail gusset 30 and a central gusset 34. The longitudinal gussets may extend from at or near the first end 16 to at or near the second end 18. The longitudinal gussets, such as the nose 28, the tail 30 and the central gussets 34, may span the entire length of the plate 1. In some cases, the gussets 28, 30, 34 may be a plurality of gussets that span part of the length of the plate 1. The gussets may extend in a suitable direction along the plate 1, such as longitudinally, diagonally, laterally and others. A plurality of cross gussets 32 may span between the longitudinal gussets, such as from the nose gusset 28 to the tail gusset 30. The cross gussets 32 may intersect with the central gusset 34. The cross gussets 32 may intersect the longitudinal gussets in a

perpendicular fashion. The cross gussets 32 may intersect diagonally. In some cases, members of the plurality of cross gussets may intersect perpendicularly and other members intersect in a diagonal fashion. The feeder pan 10 may comprise tail reinforcing ribs 48 positioned on the bottom side of the plate 1 that extend between the tail edge and other parts of feeder pan 10, such as the tail flange 26 or the tail gusset 30 for reinforcing the tail edge. Nose reinforcing ribs 46 may be positioned on the bottom side of the plate and extend between the nose edge 12 and the nose gusset 28 for reinforcing the nose edge. Central gusset 34 may extend to a height less than adjacent longitudinal gussets 28, 30. [0040] Referring to Figs. 4 and 5, gussets may define corresponding lower cavities 36. As an illustrative example, nose gusset 28, tail gusset 30 and cross gussets 32 may together define lower cavity 36.

[0041] Referring to Figs. 1 and 3, feeder pan 10 may comprise a wear pad 2. The wear pad 2 may be used as a replaceable layer in locations of high impact and wear and tear during use. After the wear pad 2 has been damaged or worn out, the wear pad may be removed and replaced with a new pad 2. The wear pad 2 may be mounted on the top face 20 of plate 1. In multiple embodiments, the wear pad 2 comprises numerous wear pads 2 mounted in areas of higher or increased wear. Wear pad 2 may be mounted in a suitable location, such as adjacent to the at least one pan wing 24. Wear pads may be mounted adjacent the one or more pan wing 24 and prevent or reduce damage caused by material moving from a center area of the plate 1 to the ends 16, 18 during use. The top face 20 may incorporate an upper cavity 37 or recess to accommodate the wear pad 2. The upper cavity 37 may be adapted to receive the wear pad. The cavity 37 may be shaped to fit wear pad 2 with a close tolerance. In some cases, wear pad 2 and upper cavity 37 mate to provide a seamless transition between the top face 20 and the wear pad 2. Referring to Fig. 2, the wear pad 2 may be fastened to the plate by suitable fasteners 4, such as bolts. The fasteners 4 may pass through apertures 38 in the upper cavity 37 and the plate 1. Fasteners 4 may be secured within the lower cavity 36. Ends of the fasteners 4 may be enclosed within lower cavity 36. Enclosing the ends of the fasteners 4 aid to protect the fasteners from damage during use of feeder pan 10. In some cases, the one or more wear pads 2 may be cast with plate 1. In such cases, the wear pads 2 may be integrated into the plate 1 and not removable. In these embodiments, apertures for fasteners to secure the wear pads 2 to the plate 1 are unnecessary.

[0042] Referring to Figs. 3 and 4, a plurality of bottom wear pads 3 may be mounted to the bottom face 22 of the plate 1. The bottom wear pads 3 may be mounted between longitudinal gussets, for example between the nose gusset 28 and the tail gusset 30. Longitudinal gussets may define apertures for receiving fasteners 5 and 6, such as nuts and bolts. The fasteners 5, 6 may be located within the lower cavity 36. Bottom wear pads 3 may be cast with plate 1, and not removable. [0043] Referring to Figs. 1 and 6B, the feeder pan 10 may comprise elements for aiding in retaining or moving bulk material toward each end of the feeder pan 10 during use. For example, feeder pan 10 may comprise at least one pan wing 24 extending upward from the top side 20 of plate 1. The pan wing 24 acts as a retaining wall to prevent or reduce bulk material on the top face 20 of the plate 1 from falling off the ends of sides of the feeder pan 10. The pan wing 24 extends upwards at or near the first end 16 of the plate 1. In some cases, feeder pan 10 comprises a plurality of pan walls with one or more pan walls located at each end of the first and second ends 16, 18. The pan wing 24 may extend past the nose edge 12 and the tail edge 14 to mate with a pan wing of an adjacent feeder pan 10A (Fig. 6B). For example, the pan wing 24 may have a stepped structure with at least one tread 24A and riser 24B to accommodate the pan wing of an adjacent feeder pan. The pan wing 24 may have multiple treads 24A, 24C. One tread 24A may compliment and mate with a tread 24C on an adjacent pan wing. Mating pan wings can form a continuous wall along the length of the feeder pans 10. Adjacent mating pan wings may comprise any complimentary shape. [0044] Referring to Fig. 6B, the feeder pan 10 may comprise a tread or grouser 48 to contact the bulk material in use. The grouser 48 may act as a wall or blocker to retain low viscosity material on the top surface 20 of the plate 1. The grouser 48 may extend longitudinally from the top surface 20 of the plate 1. In some cases, the grouser 48 may extend only partially between the ends 16, 18 of the plate 1, leaving gaps between the grouser 48 and the pan wing 24. Material may move through the gap and top wear pad 2 may be positioned to take the brunt of the wear in use. The grouser 48 may comprise a grouser wing 49 adjacent to the grouser 48 for reinforcing the grouser 48 and providing additional guidance to bulk material to be transported.

[0045] Referring to Fig 1, the feeder pan 10 may be comprised of any suitable material, for example, parts of the feeder pan 10 may comprise a material that can be cast, such as steel, manganese steel and others. A suitable material may have high impact strength, resistance to abrasion and self-lubricating properties. In some cases, one or more of the wear pads 2, 3 comprise manganese steel. The wear pads 2, 3 may comprise any suitable material that resists wear. The feeder pan 10 may be entirely cast with manganese steel. Manganese steel is intended to also encompass Mangalloy, Hadfield steel or other alloys with manganese.

[0046] Referring to Figs. 7 and 8, the feeder pan 10 may be assembled as part of an apron feeder. Feeder pans may be assembled and form a continual belt or conveyor to move material a desired distance. The belt may have directionality, such that the nose edge of the feeder pan is the leading edge of the continuous belt. Apron feeders may be used to extract or feed large, lumpy, abrasive and heavy ores under severe impact conditions, such as wet, sticky or frozen operations. Apron feeders 52 may comprise feeder pans 10, one or more chain assemblies 55, one or more drive sprockets 56 with drive shaft, idler shaft with tension idlers, and support and return rollers. Feeder pans may be supported by impact rails between links in the chain assembly.

[0047] The feeder pan 10 may comprise a chain attachment section 60 for securing the feeder pan to the chain assembly 55. The chain attachment section 60 may be reinforced with gusset structures on the bottom side 22 of the feeder pan 10. The chain attachment section may define a chain bolting surface 66 and apertures 67 for the fasteners 58 (Figs. 4 and 8).

Fasteners 58 may secure the chain attachment section 60 and the feeder pan 10 to the chain assembly 55. The chain assembly may comprise a series of chain links 54 that form a continual belt. The chain assembly 55 and the chain links 54 may engage with a gear, such as a drive sprocket 56, which drives movement of the chain assembly 55 and secured feeder pans 10. A drive sprocket 56 may be connected to a power source (not pictured), such as a motor, that provides the power to rotate the drive sprocket 56.

[0048] It is contemplated herein that at least a portion of feeder pan 10 may be cast. Casting the feeder pan 10 may improve the resistance of the feeder pan 10 to degradation caused by bending, breaking and/or cracking. Casting one or more parts of feeder pan 10 may increase the strength of the pan 10 and lessen damage from deflection, vibration and/or cracking. It is contemplated that a percentage of the feeder pan may be formed by a casting process, such as 0-100%. Casting at least a portion of feeder pan 10 may decrease routine maintenance of the feeder pan 10 where portions of the feeder pan are cast while others are bolted to the cast, a hybrid cast feeder pan is provided.

[0049] Cast feeder pan 10 is manufactured by a casting process. In some cases, cast feeder pan 10 is formed by a sand molded casting process. A typical sand molding process comprises molds made of sand and may include vacuum molding. In sand molding, a plastic covering, such as thermofoil, is applied over an aluminum or wood pattern and heated. Vacuum is then applied through small openings in the thermofoil pattern. Sand is applied over the thermofoil and vacuum molding may be used to make a form and hold the sand in place within the flask. The molted casting material is then poured in the mold. Once the metal has solidified, the vacuum is released and the sand runs out freely, releasing the casting.

[0050] Referring to Fig. 9, an exemplary method for manufacturing a cast feeder pan, such as cast feed pan 10 outlined herein, is provided. A sand mold is first created under vacuum. The material used, such as manganese steel, is heated to an appropriate melting temperature, such as l500°C, and poured into the mold (step 100). The material is allowed to rest within the sand molds as the material cools (step 110). The resting time may be between 1-1.5 hours. In some cases, resting for longer than 1.5 hours can cause cracking in the molding. The forms may then be removed (step 120). In cases where a sand molding process is used, the vacuum may be released to allow the sand to flow freely and release the casting. After the forms are removed, the gating system (not shown) and columns 64 may be cut off and the casting 10 is cleaned (step 130). The casting may be visually inspected prior to heat treatment. The feeder pan 10 is then quenched (step 140). Quenching may comprise setting one or more castings, such as four castings, on supports positioned in two rows on a furnace cart with sufficient space between them for heat and water flow. The supports may also prevent deformation of the pans while heated to quenching temperature. [0051] An exemplary method of heat treatment and quenching is provided herein. 1) Ramp up the temperature to 600°C with 200°C/ hour rate of increase; 2) hold the temperature at 600°C for 2 hours; 3) ramp up to 900°C with 200°C/hour rate; 4) hold at 900°C for 2 hours; 5) ramp up to l050°C with 200°C/hour rate; 6) hold at l050°C for 6 hours; and 7) quench from l050°C in water. Quenching water may be maintained at lower temperatures (such as below 30°C) by a suitable method, such as cooling the quenching tank.

[0052] After quenching, feeder pan 10 may be pressed to ensure straightness and remove any twist that formed after heat treatment/quenching (step 150). The feeder pan 10 may be inspected with LPI (liquid penetrant inspection) to ensure defect free casting. Castings that pass the inspection may be further machined and additional casted or non-casted components, such as wear pads, may be installed (step 160).

[0053] It will be appreciated that any suitable attachment format or mechanism may be used for connecting the feeder pan 10 to the drive element, such as a chain or belt. Typically the attachment format or mechanism is positioned outside of the pan wings and typically comprises apertures for receiving bolts for bolting the pan to the drive element.

[0054] It will be appreciated that the embodiments outlined herein are illustrative or exemplary embodiments. The skilled artisan will be aware of modifications, substitutions, and variants and each of these is within the spirit and scope of the invention and as defined by the claims. All reference to embodiments, examples, illustrations, dimensions, variants, etc., is intended to be non-limiting.

Claims

WHAT IS CLAIMED IS:

1. A feeder pan for use in forming a continuous feeder pan conveyor for transporting a bulk material, the feeder pan comprising:

a plate defined by a longitudinal nose edge and an opposed longitudinal tail edge and a first end opposed by a second end spanning the nose edge and the tail edge, and having a top side for supporting a bulk material and a bottom side opposed the top side;

an at least one pan wing extending from the top side at or near a first end of the plate; a tail flange extending from the longitudinal tail edge;

a nose gusset and a tail gusset each extending longitudinally from the bottom side of the plate from at or near the first end to at or near the second end; and

a plurality of cross gussets spanning from the nose gusset to the tail gusset defining corresponding lower cavities.

2. The feeder pan of claim 1, further comprising an at least one central gusset that extends longitudinally between the nose gusset and the tail gusset.

3. The feeder pan of any one of claim 1 - 2, further comprising at least one wear pad on the top face of the plate.

4. The feeder pan of claim 3, wherein the at least one wear pad is mounted adjacent to the at least one pan wing.

5. The feeder pan of any one of claim 3 - 4, wherein the top face of the plate comprises an upper cavity adapted to receive the wear pad.

6. The feeder pan of any one of claim 3 - 5, wherein:

the wear pad is fastened to the plate by fasteners; and

the fasteners pass through apertures in the plate and the fasteners are secured within the lower cavity.

7. The feeder pan of any one of claim 3 - 6, wherein the wear pad comprises manganese steel.

8. The feeder pan of any one of claims 1 - 7, wherein:

the nose edge of the plate comprising a nose riser extending inward from the nose edge;

the tail edge of the plate comprises a tail riser extending inward from the tail edge; and the tail flange is connected to the tail edge of the plate at a base of the tail riser.

9. The feeder pan of claim 8, wherein the nose riser and the tail flange are adapted to form a continuous longitudinal seal with a corresponding tail flange and nose riser, respectively, of an adjacent feeder pan.

10. The feeder pan of any one of claims 8 - 9, further comprising:

nose reinforcing ribs positioned on the bottom side of the plate that extend between the nose edge and the nose gusset; and

tail reinforcing ribs positioned on the bottom side of the plate that extend between the tail edge and/or tail flange and the tail gusset.

11. The feeder pan of any one of claims 1 - 10, wherein the feeder pan comprises manganese steel.

12. The feeder pan of any one of claims 1 - 11, further comprising a grouser extending longitudinally from the top surface of the plate.

13. The feeder pan of any one of claims 1 - 12 wherein the feeder pan is between ten feet and twenty feet in length.

14. An apron feeder comprising the feeder pan of any one of claim 1 - 13.

15. The feeder pan of any one of claim 1 - 14, wherein the feeder pan is formed by a casting process.

16. The feeder pan of any one of claim 1 - 14, wherein at least a portion of the feeder pan is formed by a casting process.