The present invention relates to a gyratory crusher frame part and in particular, although not exclusively, to a topshell and spider assembly forming an upper region of the crusher frame.
Gyratory crushers are used for crushing ore, mineral and rock material to smaller sizes. Referring to
Upper frame 101 may be further divided into a topshell 111, mounted upon lower frame 102 (alternatively termed a bottom shell), and a spider 114 that extends from topshell 111 and represents an upper portion of the crusher. Spider 114 comprises two diametrically opposed arms 110 that extend radially outward from a central cap 112 positioned on a longitudinal axis 115 extending through frame 100 and the gyratory crusher generally. Arms 110 are attached to an upper region of topshell 111 via an intermediate annular flange 113 that is centred around longitudinal axis 115. Typically, arms 110 and topshell 111 form a unitary structure and are formed integrally.
A drive (not shown) is coupled to main shaft 107 via a drive shaft 108 and suitable gearing 116 so as to rotate shaft 107 eccentrically about longitudinal axis 115 and to cause crushing head 103 to perform a gyratory pendulum movement and crush material introduced into crushing gap 104.
Example gyratory crushers having the aforementioned topshell and spider assembly are described in U.S. Pat. No. 2,832,547; US 2002/017994; WO 2004/110626 and US 2011/0192927.
In order to maximise the opening into the crushing zone, it is conventional for the spider arms 110 to extend from the annular flange 113 at the flange outermost perimeter. As the flange 113 extends radially outward beyond the circumferential wall of the topshell 111, reinforcements are typically required on the external facing surface of the topshell walls being positioned directly below the spider arms 111.
These reinforcing ribs that act to transmit the axial forces imparted onto the topshell 111 from spider 110 are necessary due to the non-optimised alignment of the spider arms 111 and the circumferential wall of the topshell. These ribs are disadvantageous as they both add additional weight to the crusher and increase complexity of manufacturing.
Accordingly, what is required is a gyratory crusher frame that addresses the above problem.
It is an object of the present invention to provide a gyratory crusher frame and a gyratory crusher that is both more convenient to manufacture, is more lightweight and minimises the creation of stress concentrations in the frame during operation resultant, in part, from the transfer of loading forces through the crusher.
The object is achieved by reducing the stress and weight at the region of the topshell immediately below the spider. In particular, the fatigue strength of the topshell is improved by reinforcing the topshell at the border with the flange and spider via a concave section at the topshell wall, the concave being aligned radially inward and extending from an outward facing surface relative to a longitudinal axis bisecting the topshell. Importantly, an upper section of the concave wall of the topshell neighbouring the flange (directly below the flange in the axial direction) is a substantially uniform curve and extends continuously in a circumferential direction around the longitudinal axis. Accordingly, the transfer of loading forces between the spider and the topshell is optimised and the need for additional reinforcement ribs below the spider arms is avoided. Additionally, longitudinal forces are transmitted from the spider arms to the topshell with minimal stress concentrations created in the topshell wall in contrast to conventional spider and topshell assemblies.
According to a first aspect of the present invention there is provided a gyratory crusher frame part comprising: a topshell mountable upon a bottom shell, the topshell having an annular wall extending around a longitudinal axis of the frame part; a spider having a plurality of arms extending radially outward from a cap positioned at the longitudinal axis, each arm of the plurality of arms having an first portion extending generally in a radially outward direction from the cap and a second portion extending generally in an axial direction from an outer region of the first portion; an annular flange positioned between the second portion of each arm and the annular wall, the flange having an outer circumferential perimeter and an inner circumferential perimeter relative to the longitudinal axis; the topshell comprising an outward facing surface and an inward facing surface relative to the longitudinal axis, the annular wall being defined between the outward and inward facing surfaces; characterised in that: a section of the wall of the topshell neighbouring the flange comprises a concave section at the outward facing surface and substantially a first half of the concave section in the axial direction closest to the flange is a substantially uniform curve extending continuously in the circumferential direction around the longitudinal axis.
Optionally, the outward facing surface of the wall at the concave section comprises a curvature extending over the range 170° to 185° in the axial direction.
Preferably the flange extends directly from one end of the concave section such that one end of the concave outward facing surface terminates at the outer circumferential perimeter of the flange.
Importantly, the first half of the concave section in the axial direction closest to the flange is devoid of any axially extending shoulders that would otherwise interrupt the continuous circumferential curve.
Preferably a majority of a second half of the concave section in the axial direction comprises a curvature profile substantially equal to a curvature profile of the first half.
Preferably the outward facing surface of the concave section comprises a curve extending continuously in the axial direction over the first half and the second half.
Optionally, the frame part further comprises a second flange, the second flange axially separated from the flange that supports the arms of the spider by the concave section formed in the outward facing surface. Preferably the frame part as claimed in any preceding claim wherein the annular wall at the concave section is curved radially outward at a position immediately below the second portion of each arm of the spider.
Optionally, a radial thickness of the annular wall at the concave section is thinnest substantially at an axially middle region between the second flange and the flange that supports the arms of the spider.
Optionally, a maximum radial distance by which the wall at the concave section extends in the first half is substantially equal to a maximum radial distance by which the wall extends at the concave section in the second half. Preferably an axial cross sectional profile of the outward facing surface at the concave section is substantially semi-circular.
Optionally, a radius of curvature of the semi-circular concave section is substantially equal to a radial thickness of the second portion of each arm of the spider.
Optionally, the second lower half of the concave section comprises a plurality of notches extending radially outward from the outward facing surface. Preferably, the outward facing surface at the concave section is a continuous interrupted curve except for the notches radially extending from the outward facing surface at the second half.
According to a second aspect of the present invention there is provided a gyratory crusher comprising a frame part as described herein.
The present invention will now be described, by way of example only, and with reference to the accompanying drawings in which:
The present gyratory crusher and crusher frame assembly comprises those components described with reference to the prior art crusher of
Referring to
The second lower portion 205 and in particular an outward facing surface 216 represents a radially outermost point, region or surface of each arm 203 relative to longitudinal axis 115. This outermost surface 216, according to the specific implementation, is formed by a section of second region 205 that is aligned parallel to axis 115.
Topshell 200 comprises circumferential walls 213 defined between an external facing surface 209 and an internal facing surface 214. Internal facing surface 214 defines, in part, a central chamber 212 that, in part, defines the crushing zone within which is mounted the crushing head and respective components described with reference to
Spider 201 is connected to topshell 200 via flange 202. Lower portion 205 of each arm 203 extends in a transverse or perpendicular alignment to planar surface 206 in a direction of axis 115. So as to spread the loading forces transmitted between spider 201 and topshell 200, the second and lower portion 205 of each arm 203 comprises a pair or wings 223 extending either side of lower portion 205 and in a direction generally following the circumferential path of flange 202. Each wing 223 thereby increases the footprint surface area of each spider arm 203 and its respective surface area contact with upper planar surface 206. In addition to wings 223, second portion 205 (that encompasses wings 223) is flared radially outward and radially inward 217 at respective inward facing surface 700 and outward facing surface 216. Each wing 223 is additionally flared circumferentially outward 218 with these flared sections 217, 218 serving to further increase the footprint size of arms 203 and the surface area contact with surface 206. Flared regions 217, 218 comprise a curvature opposite to a curvature of junction 219 between radial arm portions 204 and axial arm portions 205. Each wing 223 tapers outwardly in a direction from first portion 203 to flange upper surface 206. Additionally, each wing 223 flares outwardly at the region of contact with upper surface 206 both in the radially inward and outward direction 217 and the circumferential direction 218. The second portion 205 of each arm 203 comprises a groove 215 extending axially in the outward facing surface 216. Groove 215 comprises a shape profile suitable to accommodate pipes or other conduits.
Topshell 200 further comprises a lower flange 221 axially separated from upper flange 202 by wall section 213. An annular seating collar 222 is positioned axially below lower flange 221 and comprises a larger diameter than flanges 202, 221 being suitable for mounting upon bottom shell 102 via mounting surface 210 orientated in a downward direction and parallel to upward facing surface 206.
Referring to
Referring to
Four notches 211 extend radially outward from the outer facing surface of lower half 401 at discrete regions evenly distributed in a circumferential direction around half 401. Notches 211 define wall sections having a flat base (or cap) and are configured to accommodate anchorage bolts or screws at the internal chamber side 212 of topshell 200.
With the exception of the notch regions 211, a curved shape profile 404 of lower half 401 is identical to a corresponding curved shape profile 403 of upper half 400. Accordingly, the curvature in the axial direction between surface 220 and surface 406 is symmetrical about the central bisecting plane 405 that extends perpendicular to axis 115.
The curve profile 403 at upper half 400, immediately below flange 202 comprises a substantially uniform curve extending continuously in the circumferential direction around axis 115 immediately below flange 202 and in particular downward facing surface 220. This endless curve 403 is devoid of support ribs or shoulders that would otherwise be positioned immediately below each spider arm 203 and extend axially below surface 220 according to known topshell and spider assemblies. Accordingly, the continuous, endless or uninterrupted curved profile 403 transits uniformly any loading forces through topshell 200 from spider arms 203. Accordingly, stress concentrations that would otherwise be created by the axial support shoulders of the known assemblies, is avoided. Furthermore, the present topshell 200 and spider 201 assembly is of reduced weight with regard to these known assemblies.
The curve profile 403, 404 that extends in the axial direction between surfaces 220 and 406 defines a semi-circular concave region 402 in which the curve extends over substantially 180° in the axial direction 115. As indicated, this curve in interrupted at lower half 401 by the discrete notch regions 211. However, other than regions 211, this curve profile 403, 404 is endless, continuous and uniform in the circumferential direction around axis 115 between flanges 202, 211. That is, the outward facing surface 209 between flanges 202, 211 is continuously curved in the axial direction 115 and is devoid of any axially straight or linear regions.
Referring to
Number | Date | Country | Kind |
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12162977.8 | Apr 2012 | EP | regional |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/055657 | 3/19/2013 | WO | 00 |