Note: Descriptions are shown in the official language in which they were submitted.
115;~ 6
1 Protective linings for the walls of containers u~ed in
the crushing and conveying of material and subjected to heavy
wear, e.g. oscillating and vibrating conveyors, bunkers, or
ball-and-rod mills, which linings are in the form of ~heets
of resilient, normally rubber type abrasive resistent mater-
ials, attached to the wall~ to be protected by means of
clamping assemblies, are known in large numbers. In the case
of cylindrical rotary mills, these clamping as~emblies al~o
act as so-called lifting plates which carry along the crush-
ing element~, u~ually balls or rolls, a the cylinder rotates
until they fall back by gravity into the cru~hing area. It
is also known that these lifting plates compri~e attachment
sections embedded in the resilient material and open towards
the wall, in which the head~ of retaining bolts engage, the
bolts being supported in parallel flanged parts of these
sections running at right angle to the length thereof.
A protective lining of this kind is disclosed, for ex-
~ ample, in German AS 1,249,058 dated Augu~t 31, 1967 to
;~ Tre1lesborgs GummifQbriks Aktiebolag, in which the support of
the resilient protective sheets comprise a metal attaohment~ectlon, open on one ~ide, with pa~allel flanges i~ whioh the
retalnin~ bolts, or the heads thereof, enBaBe. On the ~up-
; port~ide of the protective sheets, thi~ type of attachment
is~non-reailient, and this makes the absorption of deforma-
tion foroes difficult. ~here is also a danger of the rubber-
metal joints becoming detaohed.
A protective lining of the t~vpe described hereinbefore
i~ alAo known from German AS 2,010,630 dated November 18,
1971 to Stahlgruber Otto Gruber GMBH ~ CO. in which the at-
~0 tachment section embedded in the clamping and lifting platescomprises channel-like flanges in which pressure parts, held
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1 by the retaining bolts, engage. ~hi~ type of contact between
the under-surface of the pressure parts and the channels in
the internal flanged parts, produces relatively high specific
pressures, because of the more or less spot- and line-contact
involved. In the case of large objects, these pressures be_
come so high that flanges are bent, bolt-heads are pulled
through and rails are bent to an unacceptable degree.
Finally, German OS 1,944,900 dated March 18, 1971 to
Continental Gummiwerke AG illustrates and describe~ a lining
for screening or crushing units in which the hollow section
is not enbedded in the clamping or lifting plates but i~ se-
cured to the underside of a metal retaining strip, attached
to the lifting plate, which may be curved or bent.
None of these known designs has been satisfactory in
practice, especially where the protective linings are sub-
jected to heavy loading and where attachment to the wall to
be protected requires considerable force, as is the case in
tubular ball- or rod-mills. In such cases it is necessary to
take into account not only the weight of the protective
lining itself, but also that of the crushing balls, rod~,
roll~ and the like, and that of the material being cru~hed,
all of whioh i~ initially lifted for a certain di~tanoe as
the drum rotates and then falls hea~ily back onto the lining
itself and the clamping and lifting plates1 thus producing
considerable shocks. This eliminates all types of clamping
and liftlng plates in which the attached sections are not em-
bedded but are merely secured to the under-surface~ (German
AS 1,249,058 dated Augu~t 31, 1967 to Trellesborgs
Gummifabrik9 Aktiebolag, German OS 1,944,990 dated March 18,
1971 to Continental Gummiwerke AG), since the metal-rubber
joints cannot withstand the enormou~ loads, and the sections
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1 become detached in a relatively short time.
Also eliminated are designs in which the pressure is
transferred to the wall to be protected over a relatively
small area, i.e. those which produce high specific pressures
since, according to the practical experience and regardless
of whether the pressure parts engage in channels in flanged
parts or not, for example, according to German AS 2,010,630
dated November 19. 1971 to Stahlgruber Otto Gruber GMBH ~
Co., this results in the section becoming bent, the attach-
ment bolts being pulled right out of the section or, whererail~ are used, in considerable bendine thereof.
In addition to this, it must be remembered that the
clamping and lifting plates holding a lining must be simple
to fit and must allow corrections. In the case of open units
which are not too large, i.e., chutes, vibrating conveyors
and the like, this presents no problem, but in the case of
cylinder mills, for example, which are not very high but are
often very long, heavy protecti~e sheets and clamping plates,
together weighing several tons, have to be able to be handled
inside them and this includes inserting the bolts into lift-
ing plates and into holes in the wall~ to be lined. Lor,g
rails compri~ing numerou~ threaded bolts are very difficult
to handle and the spacing between the bolts and between the
holes in the wall must match very accurately.
It is the purpose of the invention to provide clamping
and lifting plate~ which are made of a resilient deformable
material such a~ a heavy rubber having good wear resistent
characteri~tics for a wear-resistent, re~ilient wall-lining,
which can easily be assembled on the spot, with adequate
mobility of the attachment elements, and which undergo no
deformation of the attachment part~ under the tightening
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forces applied to the bolt~.
Since, according to the invention, known embedding of a
metal retaining section in a clamping and lifting plate made
of a resilient material is ideally combined with mobile
retaining element~ in ~uch a manner that the pressure applied
to the bolts is distributed over a large area, the specific
pressure upon the section i~ reduced, thus preventing the
flanged parts of the section from being bent under heavy
pressures. In spite of thi~ advantage, however, the parts
which reduce the specific pressure are designed in such a
manner that they can easily be handled when the protective
linings held by the clamping and lifting plates are being
assembled, i.e. they can be shifted back and forth,and they
cause no unnecessary weight increase. This in turn means that
spacing errors have no effect upon the fitting of bolts to the
attachment rails, or when holes are drilled in the walls to be
protected. Furthermore, the rail-sections according to the
invention are ea~ier to fit into the attachment ~ections than
rails which extend over the entire length, or over a
substantial part of the length of the plates.
A clamp assembly for securing protective lining to walls
of machinery used in orushing and conveying of abrasive
materials accordine to the present invention comprises a body
member, a metal attachment mean~ in the form of an elongate >
channel having an open narrow throat portion exposed to one
side of said body member, said narrow throat portion being
defined by two inwardly directed inclined flanges providing
bearing ~urfaces to either side of said throat. A plurality
of retaining bolts each having an associated rail piece are
slidably insertable within the channel and retained therein by
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the flanges. Each rail piece locates and supports a bolt
generally centrally and distributes the bearing force exerted
by each bolt to the bearing surfaces. Each rail piece is of a
length at least three times the bolt head diameter and has
mating surfaces for contacting the bearing surfaces in an
overlapping relationship. ~he flanges are angled into the
channel and the mating surfaces of the rail pieces have a
complimentary angle whereby the effective overlapping bearing
surface is increased to distribute the force to a greater
surface area. ~he clamping assembly is secured by engaging
said bolts with the walls of such machinery.
Preferred embodiments are shown in the drawings wherein
Figure 1 is a cross section through the clamping assembly
installed in a machine and Figure 2 i9 a section
along line II-II as indicated in Figure 1.
In the drawing attached hereto, 1 represents a wall to be
protected, i.e. in a rod- or ball-mill, the side facing
orushing chamber 2 being lined with protective sheets 3 of
abrasion-resistant rubber. ~he said sheets are held by
olamping and liftlng members 4 which not only secure the said
sheets but, by virtue of the fact that they project beyond the
surfaoe thereof, also serve to lift the orushing elements
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1 and the material to be crushed, for certain distance as the
drum rotates; thereafter, the said elements and material fall
back onto the remainder of the material in the crushing
chamber. On the other hand, if members 4 are to be used
merely as clamp~, they may lie flush with the sheets.
Embedded into clamping and lifting members 4 are metal
attachment sections or channels generally marked 5 each in
the form of a "C" shaped profile 6 open towards wall 1.
Spot-welded to thi~ profile i9 a transverse web 8 which pro-
jects therefrom on both sides and forms anchoring flanges.
For the purpose of clamping sheets ~, the clamping and
lifting plates are pressed towards wall 1 by means of bolts
10, the heads of which rest upon rail-pieces 11, one such
piece being provided for each bolt and the length of the said
rail-piece being about three to four times the diameter of
the head of the bolt, e.g. 100 mm. However, the head of the
bolt must not be secured to the rail-piece. It is sufficient
that the bolt be prevented from rotating therein by some
means such as an indentation 12 or the like.
According to the desirable example of embodiment illus-
trated in the drawing, inner flanges 13 of profile "C" shaped
profile 6 are bent upwardly at an angle to the horizontal,
whereas sides 14 of rail 11 are bent downwardly and allowing
the bolt to be pulled out. In special cases, i.e., when e~-
tremely high pressures are to be e~pected, a bushing 15 may
be fitted between wall 1 and flange 13.
AltXough preferred embodiments of the invention have
been described herein in detail, it will be appreciated by
those ~killed in the art that variations may be made hereto
~0 without departing from the spirit of the invention or the
~aope of the appended claims.
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