Abstrict This invention is a wear ring assembly for centrifugal rock crushers,
and it comprises an annular wear ring member of hardened, brittle
metal preferably having a Brinell hardness number of 600-800 a
chrome content of 12-30% by weight and a carbon content of 2.6-3.3%
by weight. The annular wear ring member forms an infeed opening
for delivery of rock to the rock crusher. A bolt ring member of
softer metal of high strength and resistance to breaking is secured
over the wear ring member to protect the rock crusher from damage
by high velocity fragments of hard, brittle wear ring material which
would otherwise occur when the wear ring member would fracture under
the impact force of large pieces of rock introduced into the rock
crusher. In one embodiment the wear ring member is formed as a plurality
of segments which are secured together as an annular ring by an
overlying bolt ring which also secures a second annular wear ring
member forming the upper portion of the annular opening.
Claims I claim:
1. A wear ring assembly for centrifugal rock crushers, comprising:
a) an annular base ring member of hardened, brittle metal, and b)
an annular bolt ring member of high strength and resistance to breaking,
overlying and secured to the base ring member.
2. The wear ring assembly of claim 1 wherein the base ring member
has a hardness of 600-800 Brinell.
3. The wear ring assembly of claim 2 wherein the base ring member
has a chrome content of 12-30% by weight and a carbon content of
2.6-3.3% by weight.
4. The wear ring assembly of claim 1 wherein the bolt ring member
is mild steel having high strength and resistance to cracking or
breaking.
5. The wear ring assembly of claim 1 wherein the base ring member
has a hardness of 600-800 Brinell, a chrome content of 12-30% by
weight and a carbon content of 2.6-3.3% by weight, and the bolt
ring member is chrome alloy steel or mild steel having high strength
and resistance to cracking or breaking.
6. The wear ring assembly of claim 1 wherein the wear ring member
comprises a plurality of segments configured to form an annular
ring, the bolt ring member is configured to overly the segments,
and fastener means removably secures the segments and bolt ring
member together.
7. The wear ring assembly of claim 6 including a second wear ring
member configured to overly the first named wear ring member adjacent
the annular opening in the first named wear ring member, the bolt
ring member being configured to overly the first named wear ring
member and a portion of the second wear ring member for securing
the second wear ring member to the first named wear ring member.
Description [0001] This application claims benefit of Provisional application
Ser. No. 60/506248 Filed 25 Sep. 2003.
BACKGROUND OF THE INVENTION
[0002] This invention relates to rock crushers, and more particularly
to a novel wear ring assembly for centrifugal rock crushers.
[0003] In order to assure that all of the incoming rock material
is thrown outwardly into impact with the anvil assembly of a centrifugal
rock crusher, a wear ring cap member is typically secured to the
upper side of the impeller assembly of a rock crusher turntable
to form an overlying top cap cover member with a central opening
therethrough for passage of rock onto the turntable and into the
impeller spaces between the underlying turntable and overlying top
cap wear ring member. Heretofore, wear rings have been provided
as simple disc-like metal plates provided with annular bolt holes
therethrough positioned to correspond with threaded bores in a plurality
of impeller units secured to the turntable.
[0004] Typically, wear rings of the prior art currently are made
of an approximately 4% chrome steel alloy material having a hardness
of approximately 400 Brinell, which is a comparatively soft material
that wears rather rapidly, typically about the life of 2-4 sets
of impellers. While this material suffers the disadvantage of a
comparatively short wear life, it is less susceptible to the occurrence
of shattering and breaking under these operating conditions than
wear rings made of harder and more brittle material that has greater
wear lives. The extensive damage that results to the rock crusher
apparatus when a broken fragment of a hardened wear ring member
is thrown off at high speed, is considered generally to outweight
the shorter wear life of the softer material ring members that are
less susceptible to breaking and cracking under operation.
SUMMARY OF THE INVENTION
[0005] In its basic form, the wear ring assembly of this invention
includes a base ring member having a hardness of 600 to 800 Brinell
and a chrome content of 12-30% and a carbon content of 2.6-3.3%
by weight, and an overlying bolt ring formed of softer steel exhibiting
high strength and resistance to cracking and breaking.
[0006] It is the principal objective of this invention to provide
a wear ring assembly that overcomes the limitations and disadvantages
of prior wear rings for centrifugal rock crushers.
[0007] Another objective of this invention is the provision of
a wear ring assembly that utilizes harder and more brittle materials
having greatly increased wear characteristics, while assuring against
separation of hard fragments that could cause damage to the rock
crusher in the event the ring member should break during operation.
[0008] Still another objective of this invention is to provide
a wear ring assembly of the class described in which a hardened
wear ring is coupled with an overlying bolt ring of softer steel
which protects against separation of hard fragments if the wear
ring should break, and thereby minimize damage to the rock crusher.
[0009] A further objective of this invention is to provide a wear
ring assembly formed of a plurality of segments secured together
in an annular configuration by an overlying bolt ring.
[0010] A still further objective of this invention is the provision
of a wear ring assembly of simplified construction for economical
manufacture and repair.
[0011] The foregoing and other objects and advantages of this invention
will appear from the following detailed description, taken in connection
with the accompanying drawings of preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a fragmentary sectional view of a first embodiment
of wear ring of this invention shown with an overlying rock infeed
funnel in broken lines and a plurality of supporting rock impeller
units also shown in fragmentary, broken line form.
[0013] FIG. 2 is an exploded perspective view of the wear ring
assembly of FIG. 1.
[0014] FIG. 3 is a cross sectional view, similar to FIG. 1 showing
a second embodiment of wear ring assembly, the same being shown
supported upon impeller units in fragmentary, broken line form.
[0015] FIG. 4 is an exploded perspective view of the wear ring
assembly of FIG. 3.
[0016] FIG. 5 is a cross sectional view, similar to FIGS. 1 and
3 showing a third embodiment of wear ring assembly supported on
impeller units shown in fragmentary, broken line form.
[0017] FIG. 6 is an exploded perspective view of the wear ring
assembly of FIG. 5.
[0018] FIG. 7 is a fragmentary cross section on an enlarged scale
of the left end portion of FIG. 5.
DESCRIPTION OF THE PREFFERED EMBODIMENTS
[0019] The wear ring assembly of this invention provides a structure
capable of utilizing harder and more brittle materials having greatly
increased wear characteristics while additionally providing means
that assures against separation of wear ring fragments that could
cause damage to the rock crusher in the event the ring member should
break during operation.
[0020] FIGS. 1 and 2 illustrate a first embodiment of wear ring
assembly embodying the features of this invention. FIG. 1 also shows
the wear ring assembly supported on a plurality of underlying impeller
units 10 10 of a centrifugal rock crusher. The wear ring assembly
also is shown in positioned position beneath a feed hopper 12 of
a centrifugal rock crusher, the feed hopper being shown in broken
lines. FIG. 1 illustrates a sectional view through the wear ring
assembly and FIG. 2 provides a perspective view of the component
parts of the wear ring assembly.
[0021] As best shown in FIG. 2 the wear ring assembly of this
embodiment comprises two interengaging ring members: a base, wear
surface ring member 14 and an overlying bolt ring member 16. Those
skilled in the art will recognize that the outer diameter of the
wear ring base member 14 is dimensioned to correspond with the diameter
of the turntable of a centrifugal rock crusher and also with the
impeller system 10 to which the wear ring is mounted.
[0022] In its preferred form, the base wear ring member 14 is formed
of a metal composition selected for particular hardness and long
wear characteristics. As an example, the base member may be formed
of ASTM A532 Chrome White Iron with a hardness of 600 to 800 Brinell
and having a chrome content of 12 to 30% by weight and a carbon
content of 2.6 to 3.3% by weight. This results in a ring member
having wear surfaces that offer a wear life of 5 to 10 times longer
than the aforementioned conventional wear ring constructions, although
the composition is more brittle and therefore potentially more susceptible
to cracking and breaking. However, as seen in FIGS. 1 and 2 the
base member 14 is configured with a raised, rounded central portion
18 defining and annular opening 20 forming a raised annular shoulder
or ledge 22 extending vertically from the upper planar surface 24
of the base member 14. The overlying bolt ring member 16 is configured
with a central opening 26 that is slightly larger in diameter than
the diameter of the annular ledge 22 in order that when the bolt
ring 16 is disposed on the upper planar face 24 of the base member
16 the edge of the central opening closely encircles the projecting
ledge portion 22.
[0023] Corresponding bores 28 28' are provided through the base
member 14 and bolt ring 16 respectively in predetermined spaced
apart arrangement corresponding to the pattern of threaded mounting
bores (not shown) associated with an impeller configuration of a
rock crusher for securement by mounting bolts 30. In the particular
embodiment of FIG. 2 the bolt bore pattern 28 28' reflects a wear
ring configured for mounting on a rock crusher turntable having
an array of six impeller assemblies.
[0024] Assembled and installed on the turntable assembly of a rock
crusher, the bolt ring 16 which is formed of a softer, for example
4% chrome alloy steel or mild steel for high strength and resistance
to cracking and breaking, firmly reinforces and strengthens the
harder and brittle base ring member 14 which is effectively clamped
between the bolt ring member and the underlying impeller structure.
[0025] As will be apparent to those skilled in the art, the capturing
engagement of the bolt ring 16 with the raised shoulder or ledge
22 positively retains the base ring member 14 against separation
should it crack, break or otherwise fracture during operation of
the rock crusher. In such an event, the base ring member 14 even
broken or fragmented will be retained in position, held by the bolt
ring 16 against being propelled explosively outward by the effects
of centrifugal force.
[0026] FIGS. 3 and 4 illustrate a second embodiment of the wear
ring assembly of this invention, differing from the first embodiment
by having a central annular wear opening 32 associated with a tapered
or chamfered surface 32', as distinguished from the rounded configuration
18 of the first embodiment. Further, the outer peripheral edge of
the base wear ring member 14' is provided with an outer raised shoulder
or ledge 34 which adds strength and rigidity to the base wear ring
member when it is worn and/or broken. The raised edge 34 also serves
to protect the bolt ring 16 from wear and abrasion during operation
of the centrifugal rock crusher.
[0027] FIGS. 5 6 and 7 illustrate a third embodiment of the wear
ring assembly of this invention which utilizes a segmented base
wear ring configuration and a separate, central, annular wear surface
ring member and bolt ring member for securing the assembly together.
In this embodiment, the wear ring member 36 (FIG. 6) is formed of
a plurality of separate, identical segments 38. Each segment is
configured with a locking groove 40 (FIG. 7) that combines with
the other segments of the ring to form an annular seating ring encircling
the inner opening 42 of the ring member for mating, seated interengagement
of the corresponding annular tab 44 on the central annular wear
ring member 46 which overlies the segmented annular ring member
36. An overlying bolt ring member 48 is configured with an inner
annular notch 50 arranged to overly and capture the tab 44 when
the bolt ring is placed into overlying position on the base ring
member 36. Mounting bolt bores 28 28" are provided as described
in connection with the earlier embodiments, for mounting the assembly
on the turntable of a centrifugal rock crusher.
[0028] It will be recognized by those skilled in the art that both
the bolt ring 48 and the central annular wear ring 46 interengage
to secure the segments of the base ring member 36 against separation,
should the base ring member be damaged or broken during operation
of the rock crusher. This segmented base ring construction and separate
central annular wear ring 46 affords a more simplified and economical
manufacture of the wear ring assembly of this invention, as well
as providing more convenient handling and storage, simpler installation
and removal during maintenance and repair operations.
[0029] It will be apparent to those skilled in the art that many
changes and modifications, other than those previously described,
may be made in the size, shape, type, number and arrangement of
parts described hereinbefore without departing from the spirit of
this invention and the scope of the appended claims. |