Patent Application
20190118185
The present invention relates to crushers such as gyratory crushers and cone crushers, and more particularly to protective liners used in crushers.
Crushers such as cone crushers and gyratory crushers are rock crushing systems, which generally break apart rock, stone, ore or other material in a crushing gap between a stationary part of the crusher frame and a moving crushing head. The crushing head gyrates about a vertical axis within a stationary shell which is part of a main frame of the crusher. To impart the gyratory motion to the crushing head, the crushing head is e.g. assembled surrounding an eccentric that rotates about a fixed shaft. The eccentric can be driven by a pinion and countershaft assembly.
The gyratory motion of the crushing head with respect to the stationary shell crushes rock, stone or other material as it travels through the crushing gap. The crushed material exits the crusher through the bottom of the crusher.
Due to the material passing the crusher and being crushed in the crushing gap, certain structural elements within such crushers, including e.g. the inner wall of a bottom shell of the main frame of the crusher below the actual crushing chamber, are subject to extensive wear.
In conventional crushers, those structural elements which are subject to wear are made from steel or clad with steel. If they are worn to a certain extent, the wear parts have to be exchanged, or the steel lining has to be replaced. In some cases, this creates substantial downtimes because the crushers have to be taken apart entirely.
U.S. Pat. No. 2,860,837 mentions an inner frame liner which is welded to an inner surface of the wall of the frame at points about the upper circumference of the liner.
Apart from such welded connections, releasable fixing structures for frame liners have been known in the art. As an example, U.S. Pat. No. 4,065,064 discloses a wear resistant lining for the inside wall of the bottom shell of a gyratory crusher which includes a plurality of flat plates made out of wear resistant steel plate and each having a pair of spaced apart holes therein. The plates are placed on the inside of the bottom shell of a gyratory crusher adjacent to each other to encircle the inside of the bottom shell. The plates are fitted with fasteners which pass through the holes in the plates and holes in the bottom shell.
EP-A1-2 859 949 describes a gyratory crusher in which a main shaft and a lower bearing are mounted within a central hub supported at a bottom shell of the crusher by radially extending arms. A modular wear resistant liner protects both the internal surface of the bottom shell and the support arms from material as it falls through the bottom shell. The liner elements are secured to an inner surface of the shell via respective attachment bolts.
It is the object underlying the present invention to provide a crusher comprising a protective liner which is easy to install and therefore also easy to replace, while providing for a longer wear life than conventional steel liners. The present invention also aims at providing a protective liner for use in such a crusher, which is e.g. a gyratory or cone crusher.
This object is achieved by means of a crusher as recited in claim 1 and a protective liner as recited in claim 17, respectively.
The crusher comprises a main frame and a crushing head mounted upon a main shaft. A crushing gap is formed between an outer surface of the crushing head and an inner circumferential surface of a mantle mounted within the main frame. The crusher further comprises at least one protective liner which is releasably fitted within the crusher, at least a part of an outwardly directed surface of the protective liner constituting a wear surface.
The protective liner is provided so as to protect a structural element of the crusher which is subject to wear due to its contact with material being processed in the crusher.
Due to the releasable fitting of the protective liner, the protective liner can be replaced quite easily and quickly.
According to the invention, the at least one protective liner comprises an elastic material layer and wear resistant inserts retained by the elastic material layer, wherein outwardly directed surfaces of the wear resistant inserts form part of the wear surface of the protective liner.
The material of the elastic material layer can be a polymer material, particularly an elastomer material, such as rubber, isoprene, polybutadiene, butadiene, nitrile, ethylene, propylene, chloroprene or silicone rubber, or a mixture thereof, including filling or auxiliary materials and impurities max. 30% by volume.
The inserts can be metallic or ceramic inserts or made from a cermet composite. If metallic, they can be of an iron based metal, including metallic carbides or oxides in a proportion of 10-40% by volume. If ceramic, they can consist of carbides or oxides of metallic elements, such as aluminum, titanium, tantalum, wolfram, chromium or zirconium or of mixtures thereof. If cermet, they can include carbides or oxides of metallic elements, such as aluminum, titanium, tantalum, wolfram, chromium or zirconium or a mixture thereof and of a metallic binder, said binder being of a plain metal or a metal alloy and having cobalt, nickel or iron as the main component of the binder.
The wear-resistant inserts can be arranged in rows in the outwardly directed surface of the elastic material layer. Every second wear-resistant member can be offset relative to the neighboring wear-resistant members in the same row.
The mutual proportions of the elastic material and the wear-resistant inserts depend on the wear conditions and the location and manner of attachment of the protective liner within the crusher. According to one embodiment, the wear-resistant inserts can be arranged and distributed about the elastic material layer so that the outwardly directed surface of at least one area of the protective liner mainly consists of the wear-resistant members.
The wear resistant inserts can be attached to the elastic material layer by vulcanizing, e.g. by vulcanizing ceramic inserts into a layer of polymer based material. Alternatively or in addition, the wear resistant inserts can be retained within the elastic material layer mechanically by means of a press fit and/or a form fit.
In general terms, the combination between wear-resistant, e.g. ceramics elements and an elastic, e.g. rubber layer is advantageous insofar as ceramics are mainly adapted to compensate for sliding or abrasive wear, whereas rubber is mainly adapted for compensating impact wear. The protective liner of the present invention thereby provides for a longer wear life than conventional steel liners. The reduction of wear will also reduce the downtimes which are needed for replacing worn parts.
Ceramic-rubber composites have been known in the art, e.g. from U.S. Pat. No. 3,607,606 which discloses a composite of rubber, natural or synthetic, and alumina-based ceramic, useful as a wear-resistant lining for ball mills, conveyors, chutes and the like. The composite comprises a layer of rubber having embedded in and bonded to the surface thereof closely spaced shaped bodies of alumina-base ceramic.
WO-A1-2006/132582 also relates to wear-resistant lining elements intended for a surface subjected to wear and which has an outwardly directed surface, over which material in the form of pieces or particles, such as crushed ore and crushed rock material, is intended to move. Chutes and truck platforms are mentioned as examples. The wear-resistant lining element comprises elastomeric material mainly adapted to absorb impact energy and wear-resistant members mainly adapted to resist wear. These are preferably made from ceramics material.
According to WO-A1-2008/087247, similar composite materials are used in wear parts of a vertical shaft impactor, e.g. distributor plates.
In order to fasten the protective liner of the invention to the crusher to protect a certain structural element from wear, several different possibilities exist.
On the one hand, the protective liner can be releasably fastened within the crusher by fastening the elastic material layer as such within the crusher. The elastic material layer can be releasably fastened to the crusher by any releasable fastening means known in the art, e.g. by means of a screw or bolt connection, by clamping or the like.
On the other hand, the protective liner may further comprise a carrier structure for supporting the elastic material layer, e.g. a metal carrier frame. If so, the protective liner can also be releasably fitted within the crusher by fastening the carrier structure within the crusher. The carrier structure can in turn be fastened by any releasable fastening means known in the art, e.g. by means of a screw or bolt connection, by clamping or the like, or simply by being seated onto a supporting structure, i.e. in a form-fitting manner.
The protective liner as such can possibly be relatively resilient due to the elastic properties of the elastic material layer. In order to provide a certain stiffness or rigidity to the protective liner, the protective liner can further comprise at least one reinforcing or stiffening element for providing an enhanced stiffness to the elastic material layer, particularly in the vertical direction.
According to the invention, at least a part of an outwardly directed surface of the protective liner constitutes a wear surface. An outwardly directed surface is a surface of the protective liner which is exposed within the crusher and therefore exposed to contact with material passing the crusher. Outwardly directed surfaces of the wear resistant inserts form part of the wear surface of the protective liner. Areas of the protective liner outside of this wear surface can, however, be devoid of any wear-resistant inserts. For example, an area near an upper edge and/or an area near a lower edge of the protective liner can be devoid of wear-resistant inserts. At least one of such areas can then suitably be used for fastening the protective liner within the crusher.
The crusher may further comprise a steel liner arranged so as to cover and protect a structural element of the crusher which is subject to wear. This can be a steel liner as it is conventionally used in crushers, e.g. a steel liner provided to an inner circumferential surface of a bottom shell of the crusher. The protective liner of the invention is then fixed to the steel liner. When the protective liner is worn, the protective liner can be replaced by a new one, while the steel liner can remain in place.
The steel liner may be integrally formed with or provided with supporting structures for supporting the protective liner during assembly and/or during operation of the crusher. For example, hooks may be welded onto the steel liner to support the protective liner during installation.
If the protective liner is fastened to a steel liner, a surface area of the protective liner may be smaller than a surface area of the steel liner, so that the protective liner covers only part of the surface area of the steel liner. This is due to the fact that the surface areas of existing steel liners are usually larger than the actual wearing zone, whereas the protective liner of the invention or its wear surface, respectively, basically covers only the actual wearing area. As a consequence, the protective liner will be worn across substantially its entire wear surface so that the maximum possible use is made of the protective liner. This reflects one possible use of the protective liner of the present invention, i.e. to add the protective liner to those portions of a steel liner which are subject to the most extensive wear.
As regards the configuration of the protective liner, the liner may be provided as one single part, or it may be assembled from several protective liner sections which are preferably arranged adjacent to each other or even coupled to each other in one way or the other.
Protective liners according to the present invention can be provided to specific locations within a crusher.
At least one protective liner can be a bottom shell liner mounted to the inner circumferential surface of a bottom shell of the main frame. Conventionally, mainframes or the shells thereof, respectively, are lined with steel. The bottom shell liner of the invention may be added to an existing steel liner of the bottom shell, or used instead of a steel liner.
Considering that the crusher will further comprise a drive shaft (countershaft) arranged to impart the gyratory motion to the crusher head, and a bottom shell of the main frame will comprise a shaft opening for the drive shaft to pass through, at least one protective liner may be a drive shaft liner mounted so as to surround a portion of the drive shaft from above. The portion of the driveshaft which is protected by the drive shaft liner extends within the crusher and is therefore subject to being hit by material having passed the crushing gap. The drive shaft liner of the invention may also be added to an existing steel cover of the drive shaft.
If the main shaft of the crusher is mounted within a central hub, at least one section of the driveshaft liner can be arranged adjacent to, and preferably fixed to, the central hub.
The driveshaft liner may include a first section extending along a portion of the drive shaft extending within the bottom shell. Further sections can be added which also extend along the drive shaft, or e.g. extend perpendicular thereto.
Considering that the main shaft can be coupled with the crushing head via a locking nut provided at an upper end of the main shaft, at least one protective liner can also be a locking nut liner provided on an outer circumferential surface of the locking nut. The locking is a quite expensive structural part of the crusher and may therefore suitably be protected by means of a protective liner of the invention.
The crusher of the invention can for example be a gyratory crusher or a cone crusher.
Finally, the present invention also provides a protective liner for a crusher as described above.
The above, as well as additional objects, features and advantages of the present invention will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, with reference to the appended drawing, where the same reference numerals will be used for similar elements, wherein:
Embodiments of protective liners according to the present invention will now be described in detail with reference to the drawings.
A crushing gap G is formed between an outer surface of the crushing head 3 and an inner circumferential surface of a mantle 9 assembled within the main frame 1. The crushing head is supported so as to perform a gyratory motion relative to the inner circumferential surface of the mantle 9. The material to be crushed is fed via the top of the crusher and is crushed in the crushing gap G between the outer surface of the crushing head 3 and the inner surface of the surrounding mantle 9. The crushed material is discharged from the bottom of the crusher.
During operation, the crushing head 3 performs a gyratory motion. A drive shaft 6 is arranged to impart the gyratory motion to the crusher head 3. This is done, in a manner known as such, by means of an eccentric arrangement (not illustrated) provided on the inside of the crushing head 3. Reference numeral 7 designates a shaft opening formed in the bottom shell 2 for the drive shaft 6 to pass through.
In accordance with the invention, the crusher illustrated in
A first protective liner 10 is mounted to the inner circumferential surface of the bottom shell 2, with a steel liner being interposed between the inner circumferential surface of the bottom shell 2 and the protective liner 10.
Reference numeral 8 designates a steel cover of the driveshaft. This steel cover surrounds the drive shaft 6, at least from above, in the area between the inner circumference of the bottom shell 2 and the outer circumference of the central hub 4, i.e. in the area where the drive shaft 6 is exposed to material which has passed the crushing gap G. The steel cover 8 terminates in a first collar adjacent to the bottom shell 2, which is visible in the Figure, and a second collar adjacent to the central hub 4, which is hidden from view. A second protective liner 20 is mounted so as to surround a portion of the drive shaft 6—or the steel cover 8 covering the drive shaft 6, respectively—from above.
A third protective liner 80 is provided on an outer circumferential surface of the locking nut 5.
These protective liners will now be described in detail.
1. Bottom Shell Liner
The protective liner 10 on the inner circumferential surface of the bottom shell 2 is illustrated in
The steel liner and the bottom shell liner 10 are illustrated in more detail in
As shown in the sectional view, protruding hooks 12 are provided to the inner circumferential surface of the steel liner 11, e.g. by welding. These hooks 12 support the protective liner sections 10′ during assembly by engaging lower edges of the protective liner sections 10′. In this embodiment, the hooks 12 are spaced apart regularly about the inner circumference of the steel liner 11.
It becomes apparent from the drawing that a surface area of the protective liner 10 is smaller than a surface area of the steel liner 11, i.e. the protective liner 10 covers only part of the surface area of the steel liner 11. The surface area of the steel liner 11 is larger than the actual wearing zone, whereas the protective liner 10 or its wear surface, respectively, basically covers the actual wearing area. As a consequence, the protective liner 10 will be worn across substantially its entire wear surface so that the maximum possible use is made of the protective liner 10. In a way, it can be said that the protective liner 10 protects the steel liner 11 which in turn protects the bottom shell 2.
In an area near the upper edge of the bottom shell liner 10, a series of through openings are provided to the sections 10′, which are spaced apart from each other in regular intervals about the circumference of the bottom shell liner 10. The through openings have a rectangular shape in this embodiment. In this embodiment, the number and spacing of the through openings corresponds to the number and spacing of the hooks 12, but this must not necessarily be the case.
On the inner circumferential surface of the steel liner 11, protruding portions are formed, which have a shape corresponding to the shape of the through openings in the protective liner sections 10′. The protruding portions can be added to the steel liner 11, e.g. by welding, or formed as an integral part with the steel liner 11, e.g. by casting.
In order to assemble the protective liner sections 10′ to the steel liner 11, the protective liner sections 10′ are fitted to the steel liner 11 so that the lower edges of the protective liner sections 10′ engage with the hooks 12 provided on the steel liner 11, while the protruding portions formed on the steel liner 11 are made to engage with the through openings formed in the protective liner sections 10′. The protective liner sections 10′ are thereby coupled to the steel liner 11 both via the hooks 12 engaging with the lower edges thereof and via the protruding portions engaging with the through openings thereof.
The enlarged detailed view in
A liner clamp 14 is provided, which has a width and height larger than the first width and heigth H1 of the through opening in the protective liner section 10′ but smaller than the second width and height H2 thereof, so that the liner clamp 14 contacts the stepped section within the through opening. By means of a bolt 15 which penetrates the liner clamp and is fit into the protruding portion 13 of the steel liner 11, the protective liner section 10′ is clamped to the steel liner 11.
As a result, the protective liner 10 can be easily replaced, without there being the necessity to release any permanent connections such as welded connections.
The configuration of the bottom shell liner 10—without the steel liner 11—is apparent in more detail from
Note that the protective liner section 10′ is illustrated having a plane shape in the drawings according to
A multitude of ceramic inlays 18 are enclosed in the rubber material on one side of the rubber plate 16, thereby configuring a wear surface below the series of through openings 17. In the mounted state of the sections 10′, the wear surface will face towards the inside of the crusher so as to be exposed to the material passing the crusher. The area near the upper edge of the rubber plate 16 which includes the through openings 17 is devoid of such ceramic inlays. A narrow area near the lower edge of the rubber plate 16 is also free from ceramic inlays.
Each wear resistant insert 18 has an outwardly directed surface forming part of the wear surface of the protective liner 10. The remainder of each insert 18 is immersed in the rubber material.
On its side opposite the ceramic inlays 18, the rubber plate is backed up by a series of vertically extending stiffening elements 19 (illustrated in dashed lines in the front view and also visible in all of the sectional views). The stiffening elements 19 are provided at the locations of the through openings 17 and are spaced apart from each other accordingly.
The stiffening elements 19 can for example be made from sheet metal. They serve for enhancing the stiffness of the liner sections 10′ in the vertical direction. In the horizontal direction, the sections 10′ have a certain flexibility in order for them to be brought into the curved shape as mentioned above.
2. Drive Shaft Liner
The driveshaft liner 20 is made up from three different sections which are mounted to the crusher in a particular order and disassembled therefrom in the reverse order. A first archway-shaped element 30 of the driveshaft liner 20 is provided for covering the driveshaft 6 from above in an area near the central hub 4—or, in this embodiment, for covering an existing steel cover 8 (cf.
The first element 30 of the driveshaft liner 20 is illustrated in more detail in
In the area of the arch-shaped polymer-ceramics part 31, the first element 30 of the driveshaft liner 20 further includes a carrier structure supporting the polymer-ceramics element. The carrier structure is provided in the form of a metal frame, the shape and configuration of which is best apparent from the sectional view in
An arch-shaped face plate 35 is provided to the front face of the element 30 which so as to face the central hub 4 in the mounted state. Outer brackets 36 are provided on a surface of the arch-shaped face plate 35 which faces away from the central hub 4 in the mounted state.
Inner brackets 37 are provided on an inner surface of the inner frame part 33. The inner brackets 37 include recesses which are adapted to become seated on matching protrusions, particularly protruding studs, provided on a supporting element within the crusher, such as the steel cover 8 of the drive shaft 6 which will be described once again in more detail below with reference to
Elements 33 to 38 form the said metal frame of the first element 30 of the drive shaft liner 20.
The second element 40 of the driveshaft liner 20 is illustrated in more detail in
The polymer-ceramics layers 41, 42 are supported by a metal frame 43. The polymer-ceramics layers 41, 42 can e.g. be plug-welded onto this metal frame 43.
The metal frame 43 has a front surface which extends essentially perpendicular to a longitudinal axis of the drive shaft 6 in the mounted state. The first polymer-ceramics layer 41 is attached to the front surface. The metal frame also has a roof surface 44 extending at right angles to the front surface. The front edge of the roof surface 44, which is joined to the front surface, is straigth. The rear edge of the roof surface 44, which is joined to the central hub 4 in the mounted state, has a curvature adapted to the curvature of the outer circumferential surface of the central hub 4.
The metal frame 43 further includes two side surfaces to which the two polymer-ceramics elements 42 are attached. The side surfaces extend at right angles to the roof surface 44 and at an angle to the front surface equipped with the first polymer-ceramics layer 41.
A stay 45 is provided along the rear edge of the roof surface 44 of the frame 43. By means of this stay 45, the second element 40 of the driveshaft liner 20 can be fastened to the central hub 4 or a surrounding ring 41 thereof, respectively. This could e.g. be done by welding the stay 45 to the central hub 4, and/or by using fastening elements such as screws or bolts.
Brackets 46 are provided to an upper portion of the metal frame 43.
The third element 50 of the driveshaft liner 20 is illustrated in more detail in
The brackets 36, 46 and the lifting eye bolts 56 are provided for the purpose of lifting the elements 30, 40 and 50 of the driveshaft liner 20, which can be relatively heavy, during installation and disassembly.
3. Locking Nut Liner
The protective liner of the present invention can be used for any arbitrary other structural element of the crusher which is subject to wear due to its contact with material passing the crusher. In order to mention a further possible example, reference is made once again to
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/057752 | 4/8/2016 | WO | 00 |
