Note: Descriptions are shown in the official language in which they were submitted.
2~22 ~
M~thod of manufacturinq a bimetal castinq
and wea~inq part Produced by thi~ method
The pre~ent invention relates to a method of
manufacturing a bLmetal casting and a wearing part
produced by this method, particularly ferrules and
crusher hammers.
Many wearing parts, for example in the field of
c~ushers, are ~ub~ected to high m2chanical ~tresses in
the mass and to high wear by abrasion on their working
~urface, ~uch that it i~ desirable that these part~
should have a high resistance to abra~ion and a certain
ductility to be able ~o re~ist mechanical ~hock stre~e~,
and po~sibly to be able to be machined. Now, it i~ well
known that these propertie~ are not compatible. I~ i~ of
15 course pos3ible to choose a steel exhibiting a c~~,- ;~e
between these two oppo ite properties, but this mUct
necessarily be done to the detriment of re~i~tance to
wear or of ductility.
In order to avoid ~uch compromi~es, it i~ known
to produce composite part in which the ~ection expo~ed
to abrasion i8 con~tituted ~y ferrochrom$um with a high
re~istance to abrasion ~upported by a core made from a
more ductile steel. Thi~ allows the w~ar of the part to
~e reduced while allowing the core to be machined and
avoidin~ its bre~k~ge during this operation. Purther-
more, it i~ posslble to reduce its manufacturing cost b~
a ~udiciou~ choice of it~ c ~-~nts.
Several man~~acturing method~ of such c~~ , 6ite
or bLmet21 parts are known. ~hu~, for example, the
~ 30 Patent ~V-64303 propo~es a manufacturing method for
: c J3ite par~3 by ~uccessive ca~ting~ of material~
~ having di~ferent or comple~entary properties. ~his
: techniqu~ however has two re~triction~. Firstly, tha
: method necessarily implies the exi~tence of a horizontal
separating ~urface between the two cast metal Further-
more, tha casting mu~t be relatively massive to allow the
~ucces~ive ca ting of th~ two metal~ while obt~ining 2
correct metallurgical bond be~ween ~hese m~tal~. The~e
two restri.ction~ lLmit the field of applica~ion of the
,
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~ 2 - ~0~22~
~olution proposed by the abovem~ntioned pat~nt.
It i~ also known to produce bimetal wearing part3
by welded assembly. A1though, in theory, a welded
assembly does not have 1Lmits at the level of -the mor
phology of the components to be assen~led~ in practice
such li~its exist and they depend on th~ welding m~thod
used. Furthermore, all welding method~ applied to
fragile materials require a perfect control o~ their
h~ating and cooling cycle, and a very accurat~ position-
in~ of the surfaces to be as~e!mbled. The result of this
i~ that a welded assemb1y is a relatively expen~ive
~echnique and is of limited applica~ion.
It is also known t~ produce bimetal partq by
brazed assembly. Thiq technique offers the possibility
of assembling components Of ~ariou~ hapes, but it ~till
reguire~ a very accurate machin;ng of the contact ~ur-
face~ and positioning devices which are alqo very accu
rate.
High tempera~ure brazing offers mechanical
p.o~e~Lie~ comparab~e with welding, but it requireq
meticulous oper~ting precaution~ and the use of special
furnaces, particularly vacuum furnace~, if its i~ deqired
to obtain a rellable assembly. ~hiR results in a rela~
ti~ely high manufacturing co~t.
With regard to low temperature brazing, ~ust lik~
glueingJ it is certainly le~s ~xpensilTe but the mechan
ical characteris~ics of the assembly are distinctly
inferior and e~en insuf~icie~t for highly ~tre sed
; wearing part~.
The e variou~ t~chniqu~ are in par~icular
le-- -n~d by the do~ EP-A~-0,271,336 for th~
manufacture of crusher ferrule~. ~he surface of Yuch a
ferrule i~ expo ed to hi~h tension3 which generate crack~
propaga~ing ~hrough ~he ~uQpo~l~ O~ the ferrllle in order
to render the latter rapidly usele~s.
The Pal;ent US-4, Og9, 988 propc)ses the u-~e of th~
technique of insert3 for the production o bimetal armour
plates, for. }~la~t fur~ace~. According to this patent,
in erts are f ir~tly ca~t in ~ir~t ~ould~, these i~sert~
.
. ~ . .. ~ .
CA 020~1221 1998-01-29
are then pl~ced in a second mould into which the part is
cast around the inserts in order to form a metallurgical
bond between the inserts and the support material. This
method has the disadvantage that the inserts undergo
thermal shocks during the casting of the parts. The
thermal shocks generate internal tensions and cracks
which propagate not only through the inserts but, because
of the metallurgical bond, also through the support.
This disadvantage appears to a greater degree when the
insertion rate is high, that is to say when the mass of
the inserts is relatively large with respect to the mass
of the support as in this case it is necessary, in order
to ensure the formation of the metallurgical bond during
the casting of the part, to further raise the casting
lS temperature of the material which is cast secondly, which
intensifies the thermal shocks and increases the risks of
cracking of the inserts.
The purpose of the pre~ent invention is to
provide a new method of manufacturing a bimetal casting
having a high insertion rate, whose properties result not
only from the individual properties of each component,
but also from a useful synergic effect generated by the
juxtaposition of the two components and due either to the
morphology or to the dimensioning or to the choice of the
materials of the components.
In order to achieve this objective, the present
invention proposes a method of manufacturing a bimetal
casting comprising ca~ting an insert in a first mould,
in disposing the insert thus cast in a second mould, and
in casting the part in this second mould around the
insert, characterised in that the casting in the second
mould is carried out in such a way as to avoid any
metallurgical bond between the insert and the cast alloy,
the bond being a mechanical bond due to an appropriate
shape of the insert.
The invention also propose~ a bimetal wearing
part produced according to this method and comprising at
least one insert made of a material with a high resis-
tance to wear and a cast support made from a more ductile
~a~ l.2~
~ Ds ~
ma~erial resis~ant ~.o mechanical stre~,ses, in which ~he
mas~ of the insert~ repre~ants at least 30% of the ma s
of th~ par~, characterised by a m~chanic~l ~ond between
the insert or inserts and the support, th~ ~aid metallur-
~ical bond being reinforced by an appropriate geometricshape of the insert.
In order of avoid the fonmation o~ a metallur
~ical bond hetween the insert;s and the ~upport and in
order to reduce the effect ,of ~h~ ~1 shocks, it i8
pos~ible~ depending on the ma~;ivenes~ of tha insert~, to
submit the latter to a prelimina~y preparation. This
preparation can for ex2mple con iStl when the ma3sivene~s
of the inserts is not too great, in a simpla heat treat-
ment. When the ma~sivene~s increa~e~, it i~ possible to
provide the in~erts with a refractory coating ~orming a
~r~l barrier. When the ma~siYane~ very great, it
is even pos~ible to envisage pro~iding the insert~ with
a ~eramic coating.
The mathod allow3, by a judiciou~ choice of the
~0 nature and morphology of the two component , the gener
ation in ~ervice o~ a ~ear profile which will maintain or
optLmi~e the work; n~ of the part.
~ he in~e~tio~ al~o provides, by way of advan-
~ageou~ appli~ation, a c~u~hsr ferrule of cylindrical or
truncated co~ 6hap~ with a c~tral bore ~or ~eceiving a
support hub co~tituted by a -~h in~ble ductile casting
on the ~urface of whioh are lo~git--A i n~ 1 ly ' ~e~e~, in
the direction of the g~neratrix, wear insert~, each
in~ert b~ing ~eparatsd fro~ the ~o ad~ac~t in~erts by
a radial fin co~tituted by a la~er of the s~id ductile
casting.
~ach in~ert can cOmpri~Q a ~ection of ~ubstan-
tially parallelepipedic ~hape con~tituting a wearing part
which i~ r~ lly prolonged towards the centre of the
ferrule by a longitn~i n~l ~arrowi~g having a "dovetail~
,~h~fi cro~ ectio~ fc in~ the zone sf m~chAnicAl bond
wl~h the ductile easting. The ~doY~ail" shaped cro~-
section ca~al~o be replac~d by rh~nnell ~ cro s~eckion~.
The ~pacing be~ween ad~acent in~ert~ can be
CA 020~1221 1998-01-29
determined by protruding radial ribs provided on the longitudinal sides of the
mserts.
According to an advantageous embodiment, the ferrule includes a first base
and a second base opposed and generally parallel to the first base. The inserts extend
from the first base to a plane disposed generally parallel to and intermediate the
bases such that a peripheral ring of ductile casting is defined by the plane and the
second base.
The invention also provides a crusher hammer constituted from a part in the
shape of a sector of circle whose inside point comprises an opening through which
a suspension and pivoting shaft can be passed and which is produced according tothe method proposed above, characterised in that the point forms a support made
from m~chin~hle ductile casting and in that the outer section is an insert having a
high resistance to wear and in that the insert and the support are integral with each
other by means of a mechanical bond.
This mechanical bond can be provided by a central prolongation of the insert
or of the support, this prolongation being provided with lateral channels. This bond
can furthermore be reinforced by a frontal groove on the support or on the insert.
The mechanical bond can also be provided by an interior sector of the insert
having a reduced thickness and with a transverse opening, the said sector of reduced
thickness being embedded in the support by the casting of the latter.
Other characteristics and features of the invention will emerge from the
detailed description of several embodiments given below by way of illustration with
reference to the appended drawings in which:
- Figure 1 is diagrammatic view of a vertical crusher;
- Figure 2 shows details of a crusher at the point of crushing;
- Figure 3 is a perspective view of a ferrule of a crushing wheel according to
the present invention;
- Figure 4 is a perspective view of a first embodiment of an insert, according
to the present invention, of a crushing ferrule;
- 6
~ FL~ures S and 6 respectively show a radial
cross-section and an axial cross section of a variant of
the ferrule shown in Figure 7;
- Figure 7 shows the peripheral wea.r of a
ferrule.
- ~igure 8 shows a view, similar to that of
Figure 4, of a second embod.Lnent of an insert of a
crushing ferrule;
- Figure 9 is a side view of a cru~her hammer
produced according to the present invention;
- Figure 10 is a central, vertical cross-section
of the hi ?r sho~n in Figure 9;
- Figure 11 shows a ~econd e~bodLment of a
crusher h - r; and
- Figure 12 ~hows the central vertical cross-
~ection of the hi -r showm in Figure 11.
A fir~t ad~antageou~ application of the use of
composite wearing part~ manufacturPd in accordance with
the present inventlon will now be described with refer-
ence to a vertical crusher with wh~el~ ~uch as showndia~ ~tically in Fiyure 1 but which will also be valid
for a pre~s with rollers. Such crushers are, for
ex~mple, used for cru~hi n~ coal or clinker. ~hey are
~ssentially con3ti~uted by a rotary track 30 over which
cru~hing wheal~ 32 moYe- ~he material to be crushed i~
inL~o~k~e~ through a cent~al feed ch~nne~ 34 and fall~
onto the track 30 wh~re it i~ s~l~h~ and c Ns~d
between that track a~d the wheel~ 32. A~ ~hown in
grsater d tail in Figure 2, the crushed material i3 taken
up, at th~ periphery of the tra~k 30, by a upward curr3nt
of hot air and at th~ ~ame time i~ separated under the
affe~t of ~ravlty a~d of a ~ep~rator 36 aceording to the
gr~n~ Lry. In order to avoid ~rictio~ between the
wheel~ 32 and the traeX 30, the wheel~ 32 mu~t ha~e
truncated co~e shape a~ ~hown in ~igure 1. It is al~o
pos~ible ~o provide wheel~ 40, a~ in ~he ~mho~i 9~t shown
in Figure 2, ha~ing a corlve~ rolling ~rfaceJ the track
38 havi~g a correspon~in~ concaYe ~nn~ r ~urface.
~he cru~hing wheel~ are gen~rally con~tituted by
.
~3 r~ 21
- 7
an annular ferrule having a cylindrical or truncated cone
shape, mount~d on a hub. They must, on the one hand,
have a sufficient resistance to the wear cau~ed by the
crushing and, at the same tLme, be able to be machined in
order to be mounted on the hub. The known ferrules are
generally cast in Ni-hard alloy or in ferrochromium and
then machined with high precision, (inside diameter with
an H6 tolerance in certain ca~ec~) before being mounted on
tneir hubs.
In service, the wear of ~uch a ferrule progresses
in a generally unifoxm ~nn~r at all poin~ along a
circular line over a radial ~ection. On the other hand,
~he wear i~ generally variable along a ~ame generatrix,
the ends, in par~icular the peripheral end~, wearing more
~lowly then the central ~ection. Furthermore, a pro-
gre~3iva polishiny of the working surfac~ is caused
resulting in an increased ri~k of ~lipping between the
ferrule and the material to be crushed.
The result of thi3 i8 that the pro~ile of the
working surface3 becomes modified and the system for
taXing up play no lon~er allow~ the opti~um cru~hing
condition to be restorad. Fur~h~ -~e/ a8 the outer
~urface heG' -~ poli~h~, the slipping be... e~ the
matexial to be cru~hed a~d the ~urface of the f~rrule
accelerates ~he wear and reduces th~ output rate, par-
ticularly if the material to be crushed is wetO
In order to overcome these di~a~va~tage~, ~he
pre~ent invention proposes, in its application to a
crusher, to prod~ce the ferrules with inserts a~ ~ho~n in
Figure 3. Su~h a ferrule i~ therefore con3tituted by a~
~nm7lAr ~uppor~ 42 made from duc ile and ~aGhin~hle
ca~ting, in which are e~bedded peripheral in~ert~ 44 mad2
from a material haYing a high resistance ~o abra~ion, for
example ferrochromium, and f~- i ng the working and
wearing surf,ace of the ferrule.
~ rhe insert~ 44 are fir~tly ca~t separately in
a~p~ iate mould~. These in~erts 44 ad~antageou~ly have
the ~hape ~hown in perspective in Figure 4. They are
co~tituted ~y an outer ~ction 46 ha~ing a ub~tan ia~ly
~ ~3 ~
8 -
p~rallelepipedic ~hape and a cro~s-~ection which i9
slightly that of a truncated cone along the radius of
curvature of the ferrule. This section is prolonged
~oward~ the base, or the in~ide of the ferrule, b~y a
longitudinal narrowed foot 48 having a radial cros8-
section of "do~etail" shape ancl formins the zone of bond
with the support 42. Each insert 44 comprise~, on at
least one of its longit~ n~l sides of the section 46, in
the embodiment shown, two protruding ribs 50.
10The ins2rts 44 ~re then placed in the mould for
the casting of the ferrules in ~uch ~ way as to lins the
entire periphery of the mould. The inserts 44 are
~uxtaposed in such a way that their rihs 50 are in mutual
contact in order to def ine, between two juxtapo~ad
15insert~, a space 52 whose width dapends on the size of
the ribs 50. The purpose of these ri~ 5Q i~ to cause,
during the casting o~ the ~u~olL 42, a spreading o~ the
ductile casting into the spaoe~ 52 in order to form,
between all of the ad~acent in~erts 44, a fine radial fin
20of ductile ca~tin~.
According to one of the features of the prese~t
i~vsntion the ca~ting of th~ fsrrule is carried out in
such a way a~ to avoid any metallurgical bond betwe~n the
~upport 42 and the ill8ert8 44. For thi~ purpose thf3
25in~ert~ 44 can ~Inde~o a prel i in;~ry preparation, for
~rl e a he~t trea~ent in or~er to reduce cracking
risk~. If the m~s~iveness of the in~ert 44 i~ relati~e-
ly larg* with respe~t to the 3upport 42 it i8 among other
things po~sible to coat the insert 44, before ca~ting the
30forrule, with a refractory coating intended to form a
t.h~ ~1 karrier.
The ~emparatuxe o~ the ma~erial ~o~ming the
~u~pO~ 4~ mu3t there~ore no longer be a~ high, during
the casting o~ the ferrule, a~ in the ca~e o~ a oa~tin~
35with the ~ormation of a metallurgical bond. ~hi~ ha~ the
ad~antage o~ reducing the thermal ~hocks which the
in~ert~ 44 unlergo durin~ thi5 ca3ting. The latter are
con~equently le88 ~ro~e~ to the ri~X~ of cra~k forma-
tion. If/ de~pite thi~ precautlon, a crack ~hould form
~-3:l2~
in ~he in~ert 44, this crack would not propagate beyond
the insert given that the absence of metallurgical bond
prevents its progression through the material of ~he
support 42. In other word~, the method proposed by the
invention reduces the risk of formation of crack~ in the
inserts 44 and furthermore prevents their progression
through the support.
The purpose of the fins 52 is to cau~e~ by the
worXing of the wheel, a preferential wear of the ductile
alloy and the formation of grooves be~ween the inserts 4
for th~ purpose of gripping the material to be crushed.
In ord~r to have optimum output it is therefore neces~ary
to choose the spacinq between the inserts 44 as a func-
tion of ths friction characteristi~s of the matQrial
used, of it~ granulomet~y and of it~ angularity.
~he morphology and the shape of the inserts 44 i~
therefo.re dictated ~y ~everal criteria. ~heir wi~th and
their spacing mu3t allow a circumferQntial pitch o~faring
an optimum driving of ths material u~ed. The profile of
the section 48 of each insert 44 all~w~ an excellent
-ch~nical ~ond between the insert~ 44 and th~ ~upport 42
with a r; ni of concentration of tension in the
ferrochromium of the in~art~. The radial height of ths
insert~ 44 allows a large u~able thic~ne~ and a good
-~h~nical bond up to the end of it~ service life.
Finally, ~he rib~ 50 allow easy ad~u3~ent and position-
ing o$ th~ in~e~ 44 in the mould~
A ferrule producad with in~ert. ~uch as described
above ha~ se~aral ad~a~tage~ with r~3pect to the k~own
ferrule8. The ma~hi~;n~ and ~erruli~g opera~ion i~ le~8
~ c~te and le88 expen~ive h~CA~I~e of the duotili$y of
th. $upport 42. Thi~ ductility al~o re~nc~s ri8k3 Of
~udden fracture through tha c ~lete cro~-sQ~tion of ~he
part a~ a result of ~tatic farruling 8tre8~e~ and of
operational fatigue. It i po~ible to use cast iron3
with a high chro~e cont~nt~ tha~ i~ to ~ay wi~h very
great hardn~s~ (grea~er ~han 65 Rc) the machining 0~
w~ich i~ ex~rem~ly difficult and ~n~ive. A~ the 8amQ
tlm2~ the mzmufacturing ~ethod allo~8 a b~tter rate of
2 ~ 2 2 1
- 1.0 ~
se Of the costly ferrochromium.
In addition to the advanta~3es 1isted above which
in fact are intrinsic ad~antages due to the propertie~ of
each of the materials present, the association of the~e
materials senerates a synergic effect offering other
advantag~s. Thus, for example, it is possible to achieve
a compression of the inser-ts by the e~pansion of the
ferrochromium during its ma:rtensitic transPormation
dnring hardening, whil~ the ducl:ile ca~t:ing completas its
19 cooling with a linear shrinkage. This compression of the
working surface has a positive effec~ on it~ resistance
to fatigue and al~o, in certain ca~es, on its re~iqtance
to abrasion. Furthermore, it is possib1e to generat~ a
wearing ~urface retAin;n~ the initial profi1e with, in
addition, hollows between ~he inserts which faYour the
driving of the material. In brief, the ferrules produced
according to the proposed method offer an increased
r~ tance to wear, an increa~ed mech~nic~l re1iabi1ity
and an increased production ra~e duriny ~heir ~erv ice
life.
~ method o~ producing a ferru1e allow~g compen-
sation of the wear profi1e a10ng the generatrix will now
be described with referencQ to Figure~ 5 to 7. In fact,
an irr~gular wear prof ile along the generatri~c i~ par-
ticularly~ harmful in the ca~e of ~ertical c~her~ with
wheel~ accordin5~ to Figure 1 in ~hich the material i3
displa~ed r~ 1 y on the traclc along the generatrix of
the whe~21s and where t}le îormation of a pocket b~tween
the whe01 and the track i responsible for harmful
3 a co~sequ~nces. In fact, the ~o~ ion rate can drop to
509~ of the ; n~l produc~ion rate obliglng a pre~aturs
raplac~ or r~-m~chinin~ of ths wheel~ bPfore the
entire u~aful l-h~ck~Q~ o~E kha wea~ g layer :i.8 ~orn out.
~urth~ -.e a metal-to-~tal contack i~ pro~l~ce~ be~wee~
the ~lightly worn end3 of the whee1 and of the track
which cause~i a rapid deterioration of the~e wearing
par~O The~e disad~antages a:ra everl ~ora prorlounced in
the ca~e of f lat trac3cs an~ of wheels hav~in~ ~traight
generatrice3 like tho~e ~ho~n in Figure lo In ~uch
5 1 ~
case th~re is an adva~age in using the pos~ibilities of
~the manufacturing method ac~ording to the presen~ inven-
tion in order to take advan~age of the presence of ~wo
mat~rial~ having different properties in order ~o accele-
S rate the wear of ~he regions which wear less than others
by consequently modifying the morphology of the inserts.
~ shown in Figures 5 and 6, the ~errule 60
comprises in~erts 62 ~hich do not extend over the entire
length of the generatrix in such a way as ~o allow a
peripheral nose 64a, which is part of the ductile casting
support 64 to l. ~ in on the outi3r edge of the wheels . A
faster wear is therefore voluntarily provoked in thi5
region of the wheel in oxder to cnmren~ate for the fact
that this region no_ ~lly wear~ more slowly. Fiquxe 7
shows the developm:3nt of the wear of ~uch a ferrule 60.
The profile identified by A repre~ent~ the outer circum~
ference of the ferrule 60 in the new unworn s~ate. Th~
line B represent~ the development of the wear profile
when the ferrule has a uni~o.rm hardne5s over the entixe
lenqth of its generatrix, while the ~l~sh~. line C
represents the development of the wear profile such as
correcta~l by a ferrule according to Figure 6 with a mora
ductile outer edg~ 64a.
A~ mant i on~l above, the special ~hape of the
in~erts 4L4, particularly their dovetail ~hape 48 contrib-
utes to consolidati~ th~ -oh~ni~l bond be~w~en the
in~erts 44 and the HU~eL ~ 42 . Whan the in~erts are
r~latively mas~ive, it i~ po~-cible, in order to increase
- the contact 5urface while avoiding having to make cut~
which ar~ too deeR i~ order to ~onm the dovetail ~hape~,
to provide in~ert~ ~uch a~ 9how~ in Figure 8. Such an
in~ert 64 i~ compaxable with ~he i~ert~ 44 of Pigure 4
e~cept that the in8ida 8ectlon 66 compri~e~, o~ its two
lonyitu~;n~l sides, corruga~ion~ or Ch~ 18 68 ~c_ in~
kind of ~ltiple dovetail. The -ch~ni~ ond zone i~
there~ore ~e]parate and i~ e~~ect ~ heh i n~ the ~ear
zone t which avoLd~ a certain ~ ~r of di~advantaga~ nt
~he end of the 8er~ice li~e with re8pect to ~he sLmpla
dovetail bec- ~ n~ level with the working 9urface.
~3~.2~
- 12 ~
Ficlure~ 9 and LO show another applica~ion usLng
a composite casting produced in accordance with the
present invention. In this instance it is a crusher
hammer. Such crushers yenerally comprise a rotary drum
on the ~urf ace of which crusher h- ~rs are attached in
a pivoting manner on longitudinal shafts. Th~ hammer 70
shown in Figure 9 has a shape which is approxi~at~ly a
sector of circle with a bore 7'2 for mounting on a shaft
in a c~usher with h; -rs. This h~- :r is a bLmetal
casting produced according to the pre~ent invention and
comprises an insert 74 made from a material with a high
re istance to wear and a support 7 6 made :Erom a more
ductile ma~erial re~istant to ~tresse~. The in~ert 74 is
firstly cast in a f ir t mould and the support 7 6 is then
cast o~er the insert 74 in another mould. The bond
between the support 76 and the insert 74 i~ an
exclusively mechanical bond. In order to consolidate
thi~ bond, it i~ preferable to pro~uce an in~ert 74
having, on the side of its bond with the support 76, a
prolongation 78 provided with lateral channel3 80. The
' ~r o~ these ~h;-nnPl 8 depend~ on the de~ires~ solidity
to be obt~in~ for these bond~. It i8 po~sible, for
exalnple, to providQ ju~t a ~ingle ch;-nnel in order to
produce a dovetail ~haped bond. In~tead of providing the
ch~nn~ 80 on a prolongation of the insert 74 it is also
pos~ible to provide them in a cut-out in the in~ert 74 in
order that the ~upport extend~ in~ide the latter.
In Qrdsr to i " ova tha f ixing in the tran~versQ
disectio~, that i~ to 8~1y pe~n~ ular to the plane of
Figure 9, it i~ po~ible to provide, on the front ~ide o~
the in~ert 74, on the . ide of the ~upport 76, a protrud
ing rib 82 or a qroove. Tha xeference 82 ~e figure 10)
show~ nuch a coll~olidating rib.
Figure~ 11 a~d 12 show another: '~A; -- t o~ a
crusher h~er 84 produced according to the pre~eIlt
inv ntion. The h~ - 84 al~o compri en an insert 88
ha~ring a hiç~h re~i~tanc~ to wear, over which i~ cast a
duckile ~upport $~. The in~ert 88 comprises, on the si.de
of the ~llpt~OL L B6, a aector 90 o~ thicknea~ reduc:ed
.
2 ~ ~
- 13 -
(3ee Figure 12) for example to the central thi~d of ~he
thickness of the re5t of th~ in~ert 88. This secto~ 90
furthermore comprises a transverse opening 92. During
the casting of the support 86, l:he casting take~ place on
either ~ide of the sector 90 of reduced thickne~s and
th~ough the opening ~ in srder to fonn the configuration
shown in cross-section in figure 12. The ~uppor~ 86 and
the insert 88 are therefors perfectly integrated in ~ach
other with an e~trem~ly stable mechanical bond in both
the tran~ve~se and longitudinal direction~. Thi~ embodi-
ment fur~-h~ -re has th~ advantage that the ~ear of the
inRert 88 follow~ the ~hape of the ductile ~U~OL ~ 86.
Finally, it must be empha~ised that the two
applica~ions described ab~ve, namely the ferrule and the
crush0r hammer, have bean pre~ented only by way of illu -
tration. Othsr application~ exi~t whi~h are capable o~
benefiting from the ad~antage~ o:Efered by the pre en~
invention, particularly applications with compo~ite
wearing part~ ha~ing a high insertion rate, for example
:eerrule~ which can be used on cyl i n~r-type de-a~glomera -
tor~ used at the output of cooling unit~ in order ~o
break up the scale arld in w~ich the insertion rate can be
in the oxder of 8096.
