The present invention relates to an abrasion wear resistant distributor plate mountable to protect a central region of a rotor within a vertical shaft impact crusher from material fed into the rotor.
Vertical shaft impact (VSI) crushers find widespread use for crushing a variety of hard materials, such as rock, ore, demolished constructional materials and the like. Typically, a VSI crusher comprises a housing that accommodates a horizontally aligned rotor mounted at a generally vertically extending main shaft. The rotor is provided with a top aperture through which material to be crushed is fed under gravity from an elevated position. The centrifugal forces of the spinning rotor eject the material against a wall of compacted feed material or specifically a plurality of anvils or retained material such that on impact with the anvils and/or the retained material the feed material is crushed to a desired size.
The rotor commonly comprises a horizontal upper disc and a horizontal lower disc. The upper and lower discs are connected and separated axially by a plurality of upstanding rotor wall sections. The top aperture is formed within the upper disc such that the material flows downwardly towards the lower disc between the wall sections and is then ejected at high speed towards the anvils. A replaceable distributor plate is mounted centrally on the lower disc and acts to protect it from the material feed. Example VSI crusher distributor plates are described in WO 95/10359; WO 01/30501; US 2006/0011762; US 2008/0135659 and US 2011/0024539.
Due to the abrasive nature of the crushable material, the distributor plate is subject to substantial abrasion wear and requires servicing or replacement at regular intervals. Due to the size and weight of the plate it is a generally difficult task to handle the plate and install and remove it at the rotor. WO 2008/147274 and WO 2011/025432 describe modular distributor plates that may be introduced and removed from the rotor in smaller sections to greatly facilitate handling. However, whilst being advantageous to reduce health and safety risks, such plates can be difficult to assemble and dismantle within the rotor as access via the crusher inspection hatch is typically restricted. Accordingly, what is required is a distributor plate that addresses the above problems.
It is an objective of the present invention to provide a vertical shaft impact (VSI) crusher distributor plate configured to be resistant to the operational abrasive wear resulting from contact with a flow of crushable feed material through the crusher rotor. It is a specific objective to provide a plate with a maximised operational lifetime that may be conveniently installed and removed at the rotor whilst being adapted for convenient locking attachment and release at the rotor via suitable attachment elements. It is a further specific objective to provide a distributor plate configured to maximise the efficiency of the VSI crusher and in particular the crushing capacity by providing an enhanced rate of flow of material through the rotor during crushing operations.
The objectives are achieved, in part, by providing a modular distributor plate assembly formed from component materials that are selected to optimise the plate (and its component parts) for maximised wear resistance, minimise thickness and weight and simplified attachment/detachment at the rotor. In particular, the present distributor plate comprises a work plate formed from a first material that mounts an insert (for example a tile) formed from a second material having an abrasion wear resistance greater than that of the work plate. Accordingly, a combined thickness of the tile and work plate (in a plane perpendicular to a contact face of the distributor plate) is minimised in addition to minimising the combined weight of the distributor plate to facilitate handling. A distributor plate having a reduced thickness relative to conventional arrangements is advantageous to increase the free flow volume above the distributor plate that is effective to maximise the through flow of material and avoid chocking.
The present distributor plate is further advantageous by comprising a mounting configuration having attachment components configured to secure the plate at the rotor exclusively at and outside a perimeter of the plate. Accordingly, service personnel are required only to access the region around the distributor plate during attachment and removal at the rotor which accordingly reduces the crusher downtime. The low profile configuration of the plate enables a corresponding low profile mounting assembly so as to maximise the available free volume above the plate which is advantageous to increase crushing capacity and efficiency.
According to a first aspect of the present invention there is provided a distributor plate assembly releasably mountable to protect a rotor within a vertical shaft impact (VSI) crusher from material fed into the rotor, the assembly comprising: a main body comprising at least one plate extending continuously within a perimeter of the distributor plate assembly; at least one abrasion resistant insert mounted at the main body to represent at least a part of a contact face of the main body positioned in an upward facing direction within the crusher to contact the material fed into the rotor, an abrasion resistance of the insert being greater than that of the main body; a plurality of attachment elements provided at the perimeter of the main body; a plurality of attachment flanges mountable to the rotor outside the perimeter of the main body to cooperate with the attachment elements to releasably clamp the main body axially to the rotor.
Preferably, a contact face of the main body including the insert is substantially planar. Additionally, the plate that defines the main body is substantially planar comprising opposed planar faces. Such an arrangement is advantageous to minimise the thickness of the plate. Accordingly, a thickness of the plate including the insert is substantially uniform within the perimeter of the main body. Optionally, a thickness of the main body including the insert in the axial direction may be less than 40 mm. Optionally, the thickness of the main body including the insert may be in a range 20 to 40 mm and optionally 28 to 32 mm. Such a configuration is advantageous to maximise the free volume within the rotor and in turn optimise the crushing capacity
Preferably, the attachment elements and flanges provided at and/or outside the perimeter of the main body are configured to secure exclusively the distributor plate at the rotor and to lock axially and rotationally the distributor plate at the rotor. In particular, the present distributor plate assembly is devoid of means to mount axially the plate at the rotor within the perimeter of the plate and in particular via a central region of the plate in contrast to conventional arrangements. Accordingly, the distributor plate assembly comprising the main body and inserts may be installed and extracted at the rotor as a single unitary body and mounted in position exclusively via the perimeter mountings.
Preferably, the attachment elements comprise lugs projecting axially downward from the main body each lug having a respective slot or bore to receive at least a part of a respective attachment flange. Preferably, the attachment flanges comprise a plurality of bolts and plate like strips or rods having a first region to engage the slot or bore and a second region to receive the bolt for clamping downwardly onto the rotor and locking the distributor plate axially downward onto the rotor. The attachment flanges may be formed from spring or high carbon steel. Accordingly, the present distributor plate is releasably locked at the rotor via the bolts exerting an axial force onto the strips or rods that act to press against the main body of the plate forcing it into clamping engagement with the base plate that is in turn releasably attached to the VSI crusher shaft and/or end cap of the shaft at which is mounted the rotor. The steel strip like attachment flanges are accordingly low profile mechanisms for securing the distributor plate in position.
Optionally, the main body comprises a work plate to form an upper part of the assembly and a support plate to form a lower part of the assembly. Optionally, the work plate comprises a first material and the support plate comprises a second material that is less abrasion resistant than the first material. Optionally, the work plate comprises an abrasion resistant steel such as manganese steel. Such a dual layer assembly is advantageous to minimise the volume of abrasion wear resistant material to form the work plate at an upper region of the distributor plate assembly whilst the support plate may comprise a less abrasion resistant material. Optionally, a thickness of the work plate including the insert may be in the range 10 to 30 mm or optionally 15 to 20 mm. Optionally, a thickness of the support plate may be in the range 5 to 15 mm or optionally 8 to 12 mm.
According to aspects of the present invention, the work and support plates are coupled together by bonding or mechanical linkages that are independent of the attachment flanges and elements that secure the distributor plate to the rotor, the bonding and mechanical linkages providing a unified coupled assembly that may be collectively installed and removed at the rotor. Optionally, the work and support plates are coupled via rivet welding and/or an adhesive so as to be permanently attached as a unified structure. Such an arrangement facilitates manipulation of the distributor plate to and from the rotor and avoids the need to assemble the plates in situ within the rotor.
Optionally, the insert may comprise at least one ceramic tile or granules. Preferably, the tiles or granules comprise a material comprising aluminium oxide, zirconia and/or silicon carbide. Such materials offer enhanced abrasion resistance relative to conventional tungsten carbides to extend the operational lifetime of the assembly and to provide a plate that is more lightweight to facilitate handling during servicing.
Optionally, the assembly may further comprise a spacer plate positioned to sit against an underside surface of the main body and against the rotor so as to be capable of being mechanically trapped between the rotor and the main body exclusively via the attachment elements and flanges at and/or outside the perimeter of the main body. The spacer plate is advantageous to adjust the axial position of the distributor plate relative to the radially outward positioned wear plates and to accordingly adjust the material flow path over the wear plates to suit material feed sizes and other feed characteristics. Via the low profile configuration of the distributor plate, the present arrangement provides flexibility of the axial positioning of the different wear components that is in turn beneficial to extend the operation lifetime of further wear components within the rotor such as carbide tip plates.
Advantageously, the weight of the present assembly may be less than 15 kg and may be in the range 5 to 15 kg or 5 to 10 kg. Optionally, the work, support and/or spacer plates may be formed as solid plates or may comprise a lattice, honeycomb or other internal structure with cavities to further reduce the overall weight of the plate assembly.
According to a second aspect of the present invention there is provided a vertical shaft impact crusher comprising a distributor plate assembly as claimed herein.
A specific implementation of the present invention will now be described, by way of example only, and with reference to the accompanying drawings in which:
Referring to
Upper horizontal disc 101 is protected from crushable material impacting the rotor 100 from above by a top wear plate 103.
Wear plates 201 are positioned to at least partially surround the perimeter of distributor plate 200 and at least partially cover an exposed surface of lower disc 102 (and upper disc 101) from abrasive wear. Referring to
Like distributor plate inserts 212, wear plate inserts 213 are formed from a non-metallic material such as a ceramic. Each plate 201 comprises a dual layer structure having a work plate 407 that mounts inserts 213 and a support plate 400 positioned axially intermediate work plate 407 and disc 102. According to the specific implementation, inserts 212 and 213 are formed as tiles and comprise an aluminium oxide ceramic. According to further embodiments, tiles 212, 213 comprise zirconia or a non-tungsten carbide such as silicon carbide whilst the main body of plates 205, 201 are formed from a metal alloy, typically steel.
A wall section 202 extends vertically upward from lower disc 102 and is sandwiched against upper disc 101. Each wall is bordered at a rearward end by rear wall 210. A wear tip shield 204 extends radially outward at the junction of wall section 202 and rear wall 210 to extend vertically upward from disc outer perimeter 300. An opposite end of wall section 202 is bordered by a holder 211 that mounts respectively an elongate wear tip 209 also aligned perpendicular and extending upwardly from one end of each wear plate 201.
Each wear plate 201 is maintained in position at lower disc 102 by a right-angle bracket 214 that is configured to engage a step 401 (and in particular a surface 905 of step 401 referring to
As indicated in
Referring to
Each lug 402 is generally planar and formed by a short plate-like body that does not extend beyond a perimeter 507 of distributor plate 200. Each lug 402 projects downwardly from support plate 206 so as to extend below a downward facing surface 503 of plate 206. An axially lowermost region of each lug 402 is positioned axially below face 503 and comprises an elongate slot 509 extending widthwise across lug 402 and aligned generally coplanar with the plane of surface 503. Each lug 402 is spaced apart around plate perimeter 507 by a uniform separation distance. According to the specific implementation, plate 200 comprises a hexagonal shape profile with each lug 402 projecting axially downward from the three sides of the hexagon. Each slot 509 is dimensioned to receive a first end 513 of the plate-like flange 403 whilst a second end 514 comprises an aperture 602 to receive threaded shaft 511 of bolt 406 configured to axially engage shoe 405 and axially clamp flange 403 axially downward against base plate 408 via contact by bold head 512. Accordingly, a lowermost surface 510 of flange 403 is forced against a lower wall 601 that defines slot 509 such that via the mating of bolt 406 into shoe 405, support plate 206 is clamped axially downward onto hub 105. According to the specific implementation, distributor plate 200 comprises axially lowermost spacer plate 207 that is free-standing to be sandwiched between support plate 206 and base plate 408. Spacer plate 207 comprises three cut-out notches 500 that are recessed into a perimeter of plate 207 to provide clearance for the lowermost regions of lugs 402 and flange ends 513. Support plate 206 is mated against spacer plate 207 via contact between a generally upward facing planar surface 501 of spacer plate 207 and downward facing planar surface 503 of support plate 206.
Support plate 206 is non-detachably coupled to work plate 205 via mating contact between an upward facing surface 504 and support plate 206 and a downward facing planar surface 505 of work plate 205. According to the specific implementation, plates 205, 206 are glued together via an adhesive. According to further specific implementations, work plates 205, 206 may be coupled via mechanical attachments including for example rivet welding, thermal bonding, or other mechanical attachments such as pins, screws or bolts. According to the specific implementation, a thickness of work plate 205 in a direction of axis 107 is in the range 15 to 20 mm whilst a corresponding thickness of support plate 206 is in the range 8 to 12 mm. The optional spacer plate 207 may comprise a thickness in the range 20 to 30 mm. According to one embodiment, distributor plate 200 comprises a total thickness in the direction of axis 107 of approximately 30 mm. This lower profile configuration is advantageous to maximise the available (free) volume within rotor 100 between the opposed lower and upper discs 102, 101 so as to maximise the through flow of material and accordingly the capacity of the crusher. The minimised thickness of distributor plate 200 is achieved, in part, by the choice of component materials. In particular, work plate 205 comprises an abrasion resistant metal alloy including for example nodular iron or a high carbon steel. Support plate 206 may comprise a less abrasion resistant steel selected to provide sufficient structural strength whilst being lightweight. Support plate 206 and optionally spacer plate 207 may comprise a solid configuration or may be formed as latticework, honeycomb or may comprise an open structure to further reduce the weight of the distributor plate 200 and facilitate handling and manipulation to, from and within the rotor 100. Providing a separate spacer plate 207 relative to the attached/bonded work and adapted plates 205, 206 is advantageous for processing of specific materials for example with varying feed size and moisture content. By adjustment of the relative axial position of contact face 216 within rotor 100, by selection of a spacer plate 207 having a predetermined axial thickness (or by omitting spacer plate 207) it is possible to optimise the position of contact face 216 axially between lower and upper discs 102, 101 and in particular the position of contact face 216 relative to wear plates 201 and the carbide tips 209. Accordingly, the service lifetime of wear plates 201 and tips 209 may be enhanced.
The single body work plate 205 is formed with a variety of holes 515 that are contained within the plate perimeter 507 and extend axially between an uppermost work surface 506 and lowermost mount surface 505 that is bonded to support plate surface 504. Each hole 515 is dimension to correspond to the shape profile of a perimeter 516 of each tile 212 so as to mount respectively each tile 212 within the main body of work plate 205 in close fitting frictional contact. Each tile 212 is secured within each respective hole 515 by an adhesive according to the specific implementation. In particular, and referring to
According to further embodiments, tiles 212 may comprise granules, chips or randomly sized pieces of high abrasion resistant material embedded within work plate 205 at work surface 506 so as to form a single continuous planar surface to define contact face 216.
Referring to
Further specific implementations of distributor plate 200 are illustrated in
Referring to
To enhance the abrasion wear resistance of each plate 201, abrasion resistant tiles 213 extend a portion of the length of plate 201 between ends 918, 919. Tiles 213 are also arranged to extend in a widthwise direction across plate 201 between a first side edge 906 and a second opposite side edge 907. In particular, tiles 213 are mounted at plate 201 at a position corresponding to the flowpath of material as it is thrown radially outward from central distributor plate 200 through outflow openings 203 corresponding to flowpath A. Each tile 213, according to the specific implementation, comprises the same abrasion resistant material as distributor plate tiles 212. The mounting of each wear plate tile 213 at wear plate 201 also corresponds to the mechanism of attachment of the distributor plate tiles 212 at work plate 205 as described with reference to
According to further embodiments, each work plate 201 may comprise a single plate 400 that mounts a plurality of tessellated abrasion resistant tiles to form the interlocking structure as described with reference to
Filing Document | Filing Date | Country | Kind |
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PCT/EP2015/064514 | 6/26/2015 | WO | 00 |