Bypass chute for mobile processing plant

Abstract

A mineral material processing plant, a system, and a method in a mobile mineral material processing plant The plant has a pre-screen (140, 141, 150) and a crusher (170). A mineral material crusher bypass chute (160) is supported (601) and pivoted (602) between an operating configuration and a lowered maintenance configuration. In the operating configuration, the bypass chute (160) directs (603) mineral material that has passed through the pre-screen (140, 141, 150) to bypass the crusher (170). In the lowered maintenance configuration, the bypass chute (160) provides (604) a working platform below the pre-screen (140, 141, 150).

Description

[0001] BYPASS CHUTE FOR MOBILE PROCESSING PLANT

[0002] TECHNICAL FIELD

[0003] The present disclosure generally relates to maintenance access to pre-screen media at mobile plants.

[0004] BACKGROUND

[0005] This section illustrates useful background information without admission of any technique described herein representative of the state of the art.

[0006] Presently, mobile plants for mineral material processing are provided with a screening stage followed by a crushing stage. In sake of simplicity, the screening stage typically forwards material on a screen medium at least partially by gravitational force towards a crusher for subsequent crushing. This requires positioning the screen medium relatively high up so that oversized material could flow with downward inclination to an inlet of the crusher.

[0007] Screen media require maintenance. In a mobile plant, access to the screen medium may require dissembling some parts to make access and use of scaffolding or the like to reach the screen medium. However, any time spent for gaining service access to the screen medium extends maintenance breaks and so impairs productivity. Moreover, with various free-standing climbing structures, some time may be required to secure such structures before service personnel may start climbing to the screen medium. It may also be difficult to position a scaffolding or the like close enough to a service entry of the screen medium.

[0008] It is an object of the present disclosure to solve or alleviate some of these problems, or to at least provide a new technical alternative for gaining maintenance access to the screen medium of a mobile plant.

[0009] SUMMARY

[0010] The appended claims define the scope of protection. Any examples and technical descriptions of apparatuses, products and / or methods in the description and / or drawings not covered by the claims are presented not as embodiments of the invention but as background art or examples useful for understanding the invention.

[0011] According to a first example aspect there is provided a system for a mobile mineral material processing plant that comprises a pre-screen and a crusher, the system comprising a mineral material crusher bypass chute; a pivot configured to pivot the mineral material crusher bypass chute between an operating configuration and a lowered maintenance configuration; wherein in the operating configuration, the bypass chute directs mineral material that has passed through the pre-screen to bypass the crusher; and in the lowered maintenance configuration, the bypass chute provides a working platform below the pre-crusher screen.

[0012] The bypass chute may comprise a crusher facing surface that in the operating configuration faces the crusher. In the lowered maintenance configuration, the crusher facing surface may provide the working platform.

[0013] The system may comprise a safety fence. The bypass chute may comprise a safety fence attachment configured to detachably attach the safety fence to the bypass chute when the bypass chute is in the lowered maintenance configuration. The safety fence attachment may be a toolless attachment. The toolless attachment may be usable without tools. The safety fence attachment may comprise one or more slots for receiving corresponding shafts. The system may comprise storage attachment for the safety fence.

[0014] The system may comprise a ladder. The bypass chute may comprise a ladder attachment configured to detachably attach the ladder to the bypass chute when the bypass chute is in the lowered maintenance configuration. The ladder attachment may be a toolless attachment. The toolless attachment may be usable without tools. The ladder attachment may comprise one or more slots for receiving corresponding shafts. The system may comprise storage attachment for the ladder. The ladder may be integrated with the bypass chute.

[0015] The storage attachment may enable detachable attaching to the mobile mineral material processing plant, e.g., on a side of the crusher, between the crusher and the bypass chute when in the operating position, or on an outer surface of the bypass chute.

[0016] The pivot may be configured to allow pivoting the bypass chute by at least 60, 70, or 80 degrees. The pivot may be configured to allow pivoting the bypass chute by at most 70, 80, or 90 degrees. The pivot may be configured to allow pivoting the bypass chute by 75 ±10 or 75 ±15 degrees.

[0017] The pivot may comprise a pivot shaft. The pivot may comprise a groove structure that defines a groove configured to mate with the pivot shaft. The groove may be formed on a lateral side of the bypass chute. The groove may have an opening portion such that the bypass chute can be detached from the pivot shaft by sliding the bypass chute such that the opening portion becomes aligned with the pivot shaft. The bypass chute may be movable such that pivot shaft becomes aligned with an opening portion of the groove and allows detaching of the bypass chute. The groove may be shaped to comprise one or more elbows. The system may comprise the groove structure on both lateral sides of the bypass chute. The groove may be configured to enable longitudinal adjustment of the bypass chute. The longitudinal adjustment may enable using the working platform for maintenance of different parts or sections of the mobile mineral material processing plant.

[0018] The bypass chute may comprise a longitudinal position adjustment arrangement. The longitudinal position adjustment arrangement may comprise the groove structure. The longitudinal position adjustment arrangement may comprise a telescoping support.

[0019] The bypass chute may comprise a side branch. The side branch may be pivotable so as to enable the pivoting of the bypass chute to the lowered maintenance configuration when the mobile mineral material processing plant resides on an even ground. The side branch may be lockable to a pivoted position in which the side branch provides a step for climbing onto the working platform.

[0020] The system may comprise a lever for pivoting the bypass chute. The lever may be coupled at or near the pivot. The lever may be detachably attachable, e.g., by slotting in or bolting to the bypass chute. The lever may have a sufficient length to allow one operator to pivot the bypass chute up or down. The system may comprise two of the levers on opposite lateral sides of the mobile mineral material processing plant. The lever, the bypass chute, and the pivot may be collectively configured such that the pivoting with the lever requires a maximum force of 800 N or 500 N. The system may comprise a spring for coupling the bypass chute with the mobile mineral material processing plant such that the spring tensions on pivoting down the bypass chute to reduce the maximum force. The reduced maximum force may be at most 250 N or at most 350 N.

[0021] The system may comprise a latch configured to automatically lock the bypass chute into its operating configuration when the latch is attached to the mobile mineral material processing plant or particularly to a main frame of the mobile mineral material processing plant.

[0022] The system may comprise a first actuator for moving the bypass chute between the operating configuration and the lowered maintenance configuration. The first actuator may comprise a hydraulic cylinder. The first actuator may comprise a pneumatic cylinder. The first actuator may comprise an electric motor. The first actuator may comprise a winch. The first actuator may comprise a jack. The first actuator may be operable by manual force. The side branch may be pivotable with the same first actuator or a second actuator. The second actuator may be identical or different with the first actuator. The second actuator may comprise a hydraulic cylinder. The second actuator may comprise a pneumatic cylinder. The second actuator may comprise an electric motor. The second actuator may comprise a winch. The second actuator may comprise a jack. The second actuator may be operable by manual force. The working platform may be a horizontal platform when the mobile mineral material processing plant is on a horizontal ground. The horizontal platform may refer to a general plane being with D per cent of horizontal plane, wherein D is at most 10, 5, or 1 . The general plane may refer to a plane defined by the working platform when neglecting protrusions smaller than 5 or 10 mm.

[0023] The working platform may longitudinally extend between a downstream end of the prescreen and a vibrator of the mobile mineral material processing plant. The vibrator may be configured to operate a vibrating feeder of the pre-screen. The vibrator may be configured to operate the pre-screen. The working platform may extend to at least halfway of a lateral length of the vibrator.

[0024] The bypass chute may extend between side plates of a main frame. The bypass chute may occupy most of lateral space between opposite sides of the main frame at the pivot point. The bypass chute may extend at the pivot over W per cent of said lateral space, wherein W is at least 80, 90, or 95. Advantageously, the bypass chute may be made as wide as feasible so as to reduce abrasion of the internal surfaces of the bypass chute. As a further or synergic advantage, the working platform may extend practically over the entire space between the side plates such that tools or parts being mounted or unmounted would not easily fall into a gap.

[0025] By pivoting the mineral material crusher bypass chute to the lowered maintenance configuration, it is possible to obtain simultaneously the working platform and access to maintenance targets at the rear part of the crusher, as further synergic advantage. For example, mounting wedges of wear parts of a jaw crusher may be attached by bolts that extend through a rear wall of the crusher. Nuts tightening the bolts may reside outside that rear wall. Thanks to the pivoting bypass chute, it is possible to avoid a need to form apertures through the bypass chute for accessing the nuts.

[0026] The crusher may reside downstream from the pre-screen.

[0027] According to a second example aspect there is provided a method comprising in a mobile mineral material processing plant that comprises a pre-screen and a crusher, the system comprising supporting a mineral material crusher bypass chute; pivoting the mineral material crusher bypass chute between an operating configuration and a lowered maintenance configuration; in the operating configuration, directing by the bypass chute mineral material that has passed through the pre-screen to bypass the crusher; and in the lowered maintenance configuration, providing by the bypass chute a working platform below the pre-crusher screen.

[0028] According to a third example aspect there is provided an apparatus comprising means for performing the method of the second example aspect.

[0029] According to a fourth example aspect there is provided a mobile mineral material processing plant that comprises the system of the first example aspect or the apparatus of the third example aspect.

[0030] Different non-binding example aspects and embodiments have been illustrated in the foregoing. The embodiments in the foregoing are used merely to explain selected aspects or steps that may be utilized in different implementations. Some embodiments may be presented only with reference to certain example aspects. It should be appreciated that corresponding embodiments may apply to other example aspects as well.

[0031] BRIEF DESCRIPTION OF THE FIGURES

[0032] Some example embodiments will be described with reference to the accompanying figures, in which:

[0033] Figs. 1 and 2 shows details of a mobile mineral material processing plant according to an example embodiment when in a bypass chute is in an operating configuration and in a maintenance configuration, respectively

[0034] Fig. 3 shows details of a mobile mineral material processing plant according to an example embodiment when the bypass chute is in an alternative maintenance configuration;

[0035] Fig. 4 shows details of a pivot of Figs. 1 to 3;

[0036] Fig. 5 shows a mineral material processing plant according to an example embodiment; and Fig. 6 shows a flow chart illustrating various steps of different example embodiments.

[0037] DETAILED DESCRIPTION

[0038] In the following description, like reference signs denote like elements or steps.

[0039] Figs. 1 and 2 shows details of a mobile mineral material processing plant 100 according to an example embodiment when in a bypass chute 160 is in an operating configuration and in a maintenance configuration, respectively. The maintenance configuration provides an access under the pre-screens 140, 141 and 150 for service and maintenance operations. A feed hopper 110 is provided to receive and collect mineral material onto a feeder 120, such as a vibration feeder. The feeder 120 feeds the mineral material onto a pre-screen 140, 141 , 150 that here comprises a first and second pre-screen portion 140, 141 , and a third pre-screen portion 150. The first and the second pre-screen portions 140 and 141 are preferably scalping screens with grizzly bars. The third pre-screen portion 150 is preferably a screen mesh. An undersize fraction of the mineral material passes through the prescreens 140 and 141 into the third pre-screen 150. An oversize fraction passes into the main branch 164 of the bypass chute 160 that is provided to direct the undersize fraction to bypass a crusher 170. An oversize fraction, on the other hand, is directed from the prescreen into the crusher 170. The mobile mineral material processing plant 100 is self- propelled with crawler tracks 180. In an example embodiment, the mobile mineral material processing plant 100 is towable. In an example embodiment, the mobile mineral material processing plant 100 comprises one or more wheels, skids, or feet.

[0040] A vibrator 130 is provided for vibrating the feeder 120, or the pre-screen 140, 141 , 150, or both.

[0041] A pivot 161 is configured to pivot the mineral material crusher bypass chute between an operating configuration and a lowered maintenance configuration.

[0042] Fig. 1 further shows a side branch 162 of the bypass chute 160. For example, an undersize fraction of the third pre-screen 150 (or of another portion) may be directed to the side branch 162 for feeding onto a different pile or side conveyor (not shown) than through a main channel 164 of the bypass chute 160.

[0043] Fig. 1 further illustrates by a dashed line a maintenance configuration of the bypass chute 160, as also better shown in Fig. 2. Moreover, Fig. 1 illustrates a safety fence in a storage position. Fig. 2 illustrates the safety fence 220 when attached to a maintenance position.

[0044] In an example embodiment, the bypass chute comprises a safety fence attachment to detachably attach the safety fence to the bypass chute when the bypass chute is in the lowered maintenance configuration, as in Fig. 2. for example, the safety fence attachment may comprise one or more slots for receiving corresponding shafts. In an example embodiment, there is further provided a storage attachment for the safety fence.

[0045] In Fig. 2, the side branch 162 of the bypass chute 160 appears to go into ground, below the level of the crawler tracks. This embodiment is not impossible to use: a suitable pile of sand can be arranged so that the side branch 162 does not hit the ground when lowered. In an example embodiment, the side branch 162 is provided with a hinge 166, as shown in Fig. 3. Hence, the side branch 162 can be hinged, e.g., sideways, such that side branch 162 of the bypass chute 160 will not collide a level ground surface when the bypass chute 160 is pivoted to the maintenance configuration.

[0046] Fig. 2 further shows a lever 230 for pivoting the bypass chute 160, here near the pivot 161 . In an example embodiment, the system comprises a spring 240 for coupling the bypass chute with the mobile mineral material processing plant such that the spring 240 tensions on pivoting down the bypass chute to reduce the force required for pivoting the bypass chute up.

[0047] In an example embodiment, the system further comprises a latch 250 that is configured to automatically lock the bypass chute 160 into its operating configuration, when the latch 250 is attached to the mobile mineral material processing plant or particularly to a main frame of the mobile mineral material processing plant. In an example embodiment, latch is biased to engage with the bypass chute 160 or a counterpart attached to the bypass chute 160.

[0048] Fig. 3 shows details of a mobile mineral material processing plant according to an example embodiment when the bypass chute 160 is in an alternative maintenance configuration B, for example, for service maintenance operations of the vibrator 130. In this example embodiment, the bypass chute 160 is longitudinally movable from a basic maintenance configuration A to the alternative maintenance configuration B. To this end, an extendable support 310 is provided by forming an elongated groove for supporting the bypass chute to one or more support pins provided on a main frame side of the mobile mineral material processing plant, preferably on both sides of the mobile mineral material processing plant. In this alternative maintenance configuration B, the working platform extends onto both sides of the vibrator 130 so providing an easy access thereto, for example, for adding grease through grease nipples (not shown) of the vibrator 130.

[0049] Fig. 4 shows details of the pivot 161 including an elongated groove 410 and a pivot shaft 420. An elongated and optionally elbowing groove 410 is formed on a side of the bypass chute 160 or a groove member attached to the bypass chute 160. The elongated groove 410 has a base portion 412 for supporting the bypass chute 160 in the operating configuration. Fig. 4 further shows two partly stabilised adapting portions 414, 416 for supporting the bypass chute 160 at different lateral positions when aligned with the pivot shaft 420.

[0050] In an example embodiment, the elongated groove 410 also provides for simple detaching mechanism: there may be an opening portion 418 in the groove that is wide enough to allow a pivot shaft 420 to leave the elongated groove 410, when the bypass chute 160 is the opening portion 418 is aligned at the pivot shaft 420 and moved such that the elongated groove 410 leaves the pivot shaft 420. In Fig. 4, the opening portion 418 opens upwards in which case the bypass chute 160 is simple to detach, but may fall if moved carelessly. With that regard, the opening may be blocked by a possibly biased blocking to avoid inadvertent dropping of the bypass chute 160. In an example embodiment, the opening portion 418 opens downwards. That way, the bypass chute may be more convenient to lift out using a crane or an excavator (with a chain, for example).

[0051] Fig. 5 shows a mineral material processing plant 100 according to an example embodiment. The mineral material processing plant 100 comprises, among others, a magnetic separator 510, a screen 520 for screening crushed material, a first discharge conveyor 530 for discharging mineral material output by the crusher 170 onto the screen 520, and an exit conveyor 440 for outputting an undersize fraction of the screen 520. The mineral material processing plant 100 typically further comprises one or more side conveyors for conveying other fractions separated by the screen 520, and I or fractions that have passed through any portion of the pre-screen.

[0052] Fig. 6 shows a flow chart illustrating various steps of different example embodiments, comprising various possible steps including some optional steps while also further steps can be included and / or some of the steps can be performed more than once:

[0053] 601. supporting a mineral material crusher bypass chute;

[0054] 602. pivoting the mineral material crusher bypass chute between an operating configuration and a lowered maintenance configuration;

[0055] 603. in the operating configuration, directing by the bypass chute mineral material that has passed through the pre-screen to bypass the crusher; and

[0056] 604. in the lowered maintenance configuration, providing by the bypass chute a working platform below the pre-crusher screen.

[0057] Various embodiments have been presented. It should be appreciated that in this document, words comprise; include; and contain are each used as open-ended expressions with no intended exclusivity.

[0058] The foregoing description has provided by way of non-limiting examples of particular implementations and embodiments a full and informative description of the best mode presently contemplated by the inventors for carrying out the invention. It is however clear to a person skilled in the art that the invention is not restricted to details of the embodiments presented in the foregoing, but that it can be implemented in other embodiments using equivalent means or in different combinations of embodiments without deviating from the characteristics of the invention.

[0059] Furthermore, some of the features of the afore-disclosed example embodiments may be used to advantage without the corresponding use of other features. As such, the foregoing description shall be considered as merely illustrative of the principles of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

Claims

CLAIMS1 . A system for a mobile mineral material processing plant that comprises a pre-screen (140, 141 , 150) and a crusher (170), the system comprising a mineral material crusher bypass chute (160); a pivot (161 ) configured to pivot the mineral material crusher bypass chute (160) between an operating configuration and a lowered maintenance configuration; wherein in the operating configuration, the bypass chute (160) directs mineral material that has passed through the pre-screen (140, 141 , 150) to bypass the crusher (170); and in the lowered maintenance configuration, the bypass chute (160) provides a working platform below the pre-screen (140, 141 , 150).

2. The system of claim 1 , wherein the bypass chute (160) comprises a crusher facing surface that in the operating configuration faces the crusher (170); and in the lowered maintenance configuration, the crusher facing surface provides the working platform.

3. The system of claim 1 or 2, wherein the system comprises a safety fence (220); and the bypass chute (160) comprises a safety fence attachment configured to detachably attach the safety fence (220) to the bypass chute (160) when the bypass chute (160) is in the lowered maintenance configuration.

4. The system of any one of preceding claims, wherein the system comprises a ladder; and the bypass chute (160) comprises a ladder attachment configured to detachably attach the ladder to the bypass chute (160) when the bypass chute (160) is in the lowered maintenance configuration.

5. The system of any one of preceding claims, wherein the pivot (161 ) comprises a pivot shaft (420); and the pivot (161 ) comprises a groove structure that defines an elongated groove (410) configured to mate with the pivot shaft (420).

6. The system of claim 5, wherein the elongated groove (410) is formed on a lateral side of the bypass chute (160).

7. The system of claim 5 or 6, wherein the bypass chute (160) is movable such that pivot shaft becomes aligned with an opening portion (418) of the elongated groove (410) andallows detaching of the bypass chute (160).

8. The system of any one of preceding claims, wherein the bypass chute (160) comprises a longitudinal position adjustment arrangement.

9. The system of any one of preceding claims, wherein the bypass chute (160) comprises a side branch; and the side branch (162) is pivotable so as to enable the pivoting of the bypass chute (160) to the lowered maintenance configuration when the mobile mineral material processing plant resides on an even ground.

10. The system of any one of preceding claims, comprising a first actuator for moving the bypass chute (160) between the operating configuration and the lowered maintenance configuration.

11. The system of any one of preceding claims, wherein the working platform is a horizontal platform when the mobile mineral material processing plant is on a horizontal ground.

12. The system of any one of preceding claims, wherein working platform extends between a downstream end of the pre-screen (140, 141 , 150) and a vibrator of the mobile mineral material processing plant.

13. The system of any one of preceding claims, wherein the bypass chute (160) fills in lateral direction most of space within a main frame of the mobile mineral material processing plant at the pivot.

14. A method comprising in a mobile mineral material processing plant that comprises a pre-screen (140, 141 , 150) and a crusher (170), the method comprising supporting (601 ) a mineral material crusher bypass chute (160); pivoting (602) the mineral material crusher bypass chute (160) between an operating configuration and a lowered maintenance configuration; in the operating configuration, directing (603) by the bypass chute (160) mineral material that has passed through the pre-screen (140, 141 , 150) to bypass the crusher (170); and in the lowered maintenance configuration, providing (604) by the bypass chute (160) a working platform below the pre-screen (140, 141 , 150).

15. A mobile mineral material processing plant that comprises the system of any one of claims 1 to 13.

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