FIELD OF THE INVENTION
The present invention relates in general to chute liners in bulk material handling, and in
particular to a mechanically interlocked ceramic chute lining system where the ceramic
blocks forming the liner are mechanically interlocked, the ceramic blocks are embedded on
a rubber matrix for providing padding effect and include a base metal adapted for fixing the
liner assembly with the chute wall by means of studs.
BACKGROUND AND PRIOR ART
In material handling operations, conveyor belts are used for conveying or transporting
material from one station to another station. When material has to be transferred between
conveyors at different heights or between conveyors moving in different directions, chutes
are used. Chutes are flat plates, having relatively smooth transferring surface, arranged at
different angles to transfer or guide materials along the chute under force of gravity. Since
the ore particles are dense and hard and discharged from the conveyor belt to the chute at
considerable velocity, they may scratch and scrape away on the surface of the chute
resulting in severe chute wear, if left unprotected. This wear may finally tear the plate,
forming holes in chute faces, leading to leakage of material. Hence chutes have to be
replaced, which activity stops the production for a long time. This downtime while the
conveyer system is not in operation, results in loss of productivity. Such losses need to be
kept at a minimum.
To avoid this, liners are used. Liners are small rectangular blocks, used as sacrificing cover
for chutes. These are mechanically fastened to the chute.
BENEFITS OF CHUTE LINING
1) Facilitates repair and replacement of sliding surface
2) Means of correcting the performance of an inadequate chute
3) Avoids abrasion wear of chute
4) Reduces impact wear, noise, dust and material degradation

5) Promotes smooth flow
6) Avoids build-up of material
7) Prevents chemical reaction or corrosion of both chute and product
Chute liners are well known in the art. They can be of hard-wear type made of steel plates
or ceramic tiles, or may be of low friction type made of UHMWPE (Ultra High Molecular
Weight Polyethylene). The choice of the material of the liners depends upon the material
handled by the system and site condition. The present invention concerns ceramic tile
liners. They are dry pressed high alumina ceramic tiles and are normally manufactured in
standard sizes. Ceramic liners have been used in the bulk solid handling industries to
address the problem of high wear and abrasion.
An example of the above referred liners can be found in the United States Patent no. US
3,607,606 where ceramic bodies are embedded in a rubber material. The ceramic bodies
have a high resistance to wear while the rubber material serves as shock absorber to reduce
the risk of the brittle ceramic bodies cracking when hit by pieces of material.
In United States Patent Application no. 12/789,272 the composite liners generally comprise
a base metal and one or more ceramic inserts embedded in the base metal. The composite
liners exhibit improved resistance to wear and therefore have a longer usable life than the
liners formed of the base metal alone.
An another example of the above referred liners can be found in Indian Patent no. 250582
wherein the wear-resistant liner has an outwardly directed surface with a certain thickness,
over which material in the form of pieces of particles is intended to move. The wear-
resistant liner comprises elastomeric material mainly adapted to absorb impact energy and
wear-resistant members mainly adapted to resist wear.
However, during different application, the liner is subjected not only to abrasion wear but
also to a certain degree of impact wear. Ceramic tiles when cemented directly on a steel
surface have the advantage of resisting abrasion wear but cannot absorb impact energy.
This has resulted in the development of liners having ceramic embedded in rubber matrix. It
has been observed that in the conventional ceramic liners there is a tendency of ceramic

blocks getting dislodged during operation. Once a single block gets dislodged, the
surrounding area becomes prone for adjacent blocks to get dislodged. This leads ultimately
to the failure of the liner. Worn or damaged liners may periodically be removed from a
chute and replaced with new liners which is disadvantageous from a maintenance point of
view as the existing conventional liners are fixed with the chute by bolting the liners with
the chute wall, thus making the replacement process difficult, labour intensive and time
consuming.
There has thus been a persistent need to design a suitable ceramic chute liner or chute
lining arrangement to improve the life of the ceramic liner which eliminates the chance of
dislodgement and further in case of dislodgement of a ceramic block, replacement is limited
to that part only without hampering the whole liner arrangement. This makes the
replacement process simple, requires less human intervention and also less time
consuming. Hence the downtime of the plant is reduced.
The present invention meets the aforesaid long felt needs and other needs associated
therewith.
OBJECTS OF THE INVENTION
The principal object of the present invention is to provide a ceramic chute liner which is
substantially durable and compact and which ensures that chances of dislodging between
ceramic blocks during operation are substantially nullified.
Another object of the invention is to provide a ceramic chute liner which has enhanced
service life at critical operating conditions which results in profitability.
Yet another object of the invention is to provide a ceramic chute liner which has Low
coefficient of friction.
Another object of the present invention is to provide a ceramic chute liner which has a
predictable wear pattern.

A further object of the invention is to provide a ceramic chute liner which reduces cost of
annual maintenance and replacement.
A further object of the invention is to provide a ceramic chute liner which allows easy
replacement and maintenance.
SUMMARY OF INVENTION
Accordingly, the present invention provides a ceramic chute liner comprising of a plurality of
mechanically interlocked ceramic blocks. The corresponding mechanically interlocked
ceramic blocks have thin rubber film between them along respective adjoining surfaces. This
ensures that the ceramic blocks are bonded with each other with substantial strength and
the impact force is substantially reduced.
Preferably, the vertical faces at the front and rear ends of each block are provided with a
contour comprising of a protruded part and a depressed part and the vertical faces at the
lateral ends of each block are plane surfaces. The blocks are adjoined along the vertical
faces at the respective front and rear ends and also along the vertical faces at the
respective lateral ends.
The protruded part of one block can securely receive the depressed part of another block for
mechanical interlocking between the blocks.
More preferably, a first thin film of rubber is provided in between vertical faces at the front
and rear ends of two adjoining blocks and a second thin film of rubber is provided between
the vertical faces at the lateral ends of two adjoining ceramic blocks.
Most preferably, the first and second rubber films and the blocks are bonded with each
other through chemical bonding and the blocks are embedded in a rubber matrix which
comprises at least a metal plate for fixing the liner on to the chute wall through studs and
the blocks of two adjacent rows are arranged to be asymmetric with each other.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

The nature and scope of the present invention will be better understood from the
accompanying drawings, which are by way of illustration of some preferred embodiments
which are exemplary and does not impose any limitation on the scope of the invention. In
the accompanying drawings,
Figurel is a top view of the ceramic liner assembly according to the present invention.
Figure 2 is the isometric view of a single ceramic block unit.
Figure 3a is a top view of a group of two such ceramic block units shown in figure 2.
Figure 3b is a top view of a group of several such ceramic units shown in figures 2 and 3a.
Figure 3c is the isometric view of a single ceramic block unit according to another preferred
embodiment.
Figure 3d is a top view of the ceramic unit shown in figure 3c.
Figure 3e is the top view of several such ceramic units shown in figure 3c and 3d
Figure 4a is the isometric view of a single ceramic block unit according to another preferred
embodiment.
Figure 4b is a top view of the ceramic unit shown in figure 4a.
Figure 4c is the top view of several such ceramic units shown in figures 4a and 4b.
Figure 5 is a lateral view of the liner arrangement shown in figure 1.
DETAILED DESCRIPTION OF THE INVENTION
The following describes exemplary preferred embodiments of the present invention, which
are purely for the sake of understanding the performance of the invention, and do not
impose any limitation on its scope.
All through the specification including the claims, the words "chute", "hopper", "conveyor",
"belt", "liner", "bulk material", "abrasion", "wear", "impact load", "rubber pad" and "ceramic

blocks", "protrusions", "depressions", "grooves", "notches or tips" are to be interpreted in
the broadest sense of the respective terms, and include all similar items in the field known
by other terms, as may be clear to persons skilled in art. Restriction or limitation if any
referred to in the specification, is solely by way of example and understanding the present
invention.
The present invention provides composite liners made up of interlocked ceramic blocks
characterized in having thin rubber film between them and the blocks being embedded on a
rubber matrix. Such a lining arrangement results in improved resistance to wear and
therefore, have a longer usable life than conventional liners. The proposed liner system
provides easy replacement of any damaged part in case of wear and thereby reduces the
downtime of a plant.
The composite ceramic liner of the present invention comprises of a plurality of ceramic
blocks that are mechanically interlocked. Each individual ceramic block is bonded with
rubber both on its vertical as well as horizontal surfaces, thereby eliminating any chance of
dislodging the ceramic blocks in use. Further, since the ceramic blocks are embedded on a
rubber covering, they help withstand impact loads. These liners are provided with steel back
plates to facilitate fixing them on the chute wall with the help of studs.
The basic constructional feature of the ceramic chute liner as described in the preceding
paragraphs and the advantages derived out of it will now be further explained in the
following description with reference to the accompanying drawings.
In the drawings, like reference numerals represent like features and the expressions "front",
"rear", "top", "lateral", "isometric", and like expressions should be construed with reference
to the orientation of the chute liner during use.
Figure 1 represents a ceramic chute liner arrangement (10) comprising of a plurality of
mechanically interlocked ceramic blocks (1) with thin rubber film between them. The
ceramic blocks (1) are embedded in a rubber matrix (2). The two adjacent rows of ceramic
blocks (1) are arranged in asymmetric way, thus further reducing the risk of dislodgement
of the ceramic blocks in the vertical direction.

Figure 5, which is a lateral view of the arrangement shown in figure 1 shows that the rubber
matrix (2) also has a back plate (9) embedded on its back face, which is adapted for fixing
the whole liner arrangement with the chute wall (not shown) by means of studs (not
shown). It would be clear from figures 1 and 5, that the liner assembly (10) is embedded in
the rubber matrix (2), to absorb the impact energy during bulk material handling.
Figure 2 is a detailed view of a ceramic block unit (1). The vertical faces (3) at the front and
rear end of each block (1) have a circular protruded part (5) and a corresponding circular
depressed part (6). The gap between the protruded (5) and depressed parts (6) at the front
end and the rear end is definite and predetermined for each block. The figure 2 also shows
the vertical faces (4) at the lateral ends of the block (1). These are plane surfaces. It can be
seen from figure 2 also that each block (1) has a top surface and a bottom surface.
Figure 3a is a view of two such ceramic blocks (1), one of which is shown in figure 2. It
would be clear from this figure that two adjacent ceramic blocks are placed side by side in
opposite direction to ensure that the protruded part (5) of one block can receive the
depressed part (6) of another block in order to achieve mechanical interlocking between the
blocks.
The protruded part (5) of a first ceramic block is complimentary to in shape and adapted to
be mechanically interlocked with the depressed part (6) of the second block and the
depressed part (6) of first ceramic block is also complimentary to in shape and adapted to
be mechanically interlocked with the protruded part (5) of the second block. This
interlocking mechanism between any two adjacent blocks ensures tight fitting of the blocks.
It would be also clear from the figures 2 and 3a that the vertical surfaces (4) at the lateral
ends of each block are plane surfaces devoid of any protruded or depressed parts.
Referring to figure 3a, a first thin film of rubber (7) is provided in between two adjoining
ceramic blocks (1) at the front and rear vertical faces (3) of each block (1). A second thin
film of rubber (8) is provided in between the vertical surfaces (4) at the lateral ends in
between two adjoining ceramic blocks (1). The ceramic blocks (1) are adjoined at vertical
faces (3) along their front and rear ends and also at the vertical faces (4) along their lateral
ends. Preferably, though not essentially, the rubber films (7, 8) and the ceramic units (1)
can be bonded with each other through chemical bonding, thus eliminating the risk of
dislodgement of the individual blocks.

Figure 3b is a top view of an arrangement of a plurality of ceramic blocks (1). The
interlocking aspect as explained with reference to figures 2 and 3a would be further clear
from this figure. It shows how a plurality of such ceramic blocks (1) is actually arranged.
However, it shows ceramic blocks (1) adjoined only along the front and rear vertical
faces(3). It should be understood that ceramic blocks (1) are also adjoined along the
vertical faces (4) along the lateral ends of each block (1) and this is within the scope of the
present invention.
Figure 3c, figure 3d and figure 3e are views of another embodiment of the wear-resistant
ceramic liners, according to the invention.
Figure 3c is a view of a ceramic block (1) provided with a contour having triangular grooves
(6) and notches (5) on the vertical faces (3) at the front and rear ends of the ceramic block
(1). The grooves (6) constitute the depressed part while the notches or tips (5) constitute
the protruded part. This contour pattern would be further clear from the top view in figure
3d. The rest of the features are all identical with the previous embodiments illustrated in
figures 2, 3a and 3b and are not reiterated for the sake of brevity.
From the arrangement shown in figure 3e it would be clear that a plurality of ceramic
blocks(l), each of which are shown in figure 3c are arranged side-by-side where the
triangular tip or notch(5) of a first block is inserted in the groove face (6) of the second
adjacent block to facilitate the mechanical interlocking between the blocks. It should be
understood that ceramic blocks (1) are also adjoined along the vertical faces (4) along the
lateral ends of each block (1) and this is within the scope of the present invention.
As in the earlier embodiments illustrated in figures 1, 3a and 3b, vertical faces (4) at the
lateral ends of each block are plane surfaces. Similarly, a first thin film of rubber (not shown
in detail in figure 3e) is provided in between two adjoining ceramic blocks (1) at the front
and rear vertical faces (3) of each block (1) and a second thin film of rubber (8) is provided
in between the vertical surfaces (4) at the lateral ends in between two adjoining ceramic
blocks (1). The ceramic blocks (1) are adjoined at vertical faces (3) along their front and
rear ends and also at the vertical faces (4) along their lateral ends.
Figures 4a, 4b and 4c are views of another preferred embodiment. These views correspond
to the views in figures 3c, 3d and 3e respectively and function exactly in the same manner
and have same features. These are not reiterated again for the sake of brevity. Only

difference is that the vertical faces (3) at the rear and front ends of each block (1) have
rectangular grooves (6) as depressed parts and rectangular notches or tips (5) as the
corresponding protruded part, which fit into each other, exactly in the same manner as
described in the previous embodiments.
The rubber layers (7,8) provided between ceramic units (1) along their adjoining
surfaces(3,4) throughout the body of the liner, provide the desired cushioning effect to
reduce the impact force which damages the ceramic blocks. This also ensures that the
ceramic blocks (1) do not get dislodged easily during operation. The rubber layer (7,8)-
ceramic surface (3,4) bonding and also the protrusion (5), depression (6) arrangement at
the front and rear vertical surfaces (3) ensure this aspect in particular, while especially, the
presence of rubber layer (7,8) provide the desired cushioning effect to reduce the impact
force.
The wear-resistant ceramic block shapes described above are only examples of conceivable
shapes. A person skilled in the art understands that other shapes are possible and all such
shapes are within the scope of the present invention. The shapes shown are not
consequential to the present invention.
As stated before, figure 5 is a view of arrangement shown in figure 1 which essentially
shows the back portion of the rubber matrix (2) of the composite liner (10). The rubber
matrix has a metal back plate (9) embedded on to it. This metal back plate (9) is adapted to
fixing the liner (10) on to the chute wall through studs (not shown). This in particular
ensures that if any ceramic block (1) needs to be replaced, this can be done easily without
causing prolonged hindrance to the operation.
The metal back plate can be made of steel. However, other materials such as iron, alloys of
iron, aluminum and so on may be used and all such material fall within the scope of the
present invention.
It would be clear from figures 1 and 5, that the liner assembly (10) comprising of
mechanically interlocked blocks, is embedded in the rubber matrix (2), to absorb the impact
energy during bulk material handling. Preferably, the mechanically interlocked blocks (1)
are fixed to the rubber matrix (2) by adhesives. The rubber matrix (2) covers the bottom as
well as the top surfaces of the composite liner. This configuration helps to withstand impact
load by providing padding effect.

The non limiting advantages of the present invention are:
1. They are substantially durable and compact and chances of dislodging of ceramic
blocks during operation are substantially nullified.
2. Enhanced service life at critical operating conditions results in profitability.
3. Low coefficient of friction.
4. Predictable wear pattern.
5. Reduces cost of annual maintenance and replacement.
6. Reduces shut down frequency, hence increases productivity.
7. No ceramic dislodges during operation.
The present invention has been described with reference to some non-limiting preferred
embodiments and drawings for the sake of understanding and it includes all legitimate
developments within the ambit of what has been described hereinbefore and claimed
hereinafter.

WE CLAIM:
1. A ceramic chute liner (10) comprising of a plurality of mechanically interlocked ceramic
blocks (1), the corresponding mechanically interlocked ceramic blocks(l) having rubber
films (7,8) between them along respective adjoining surfaces (3,4) such that, the
ceramic blocks (1) are bonded with each other with substantial strength and the impact
force is substantially reduced.
2. The chute liner (10) as claimed in claim 1, wherein the vertical faces (3) at the front and
rear ends of each block (1) are provided with a contour comprising of a protruded part
(5) and a depressed part (6) and the vertical faces (4) at the lateral ends of each
block(l) are plane surfaces and blocks(l) are adjoined along the vertical faces (3) at the
respective front and rear ends and also along the vertical faces (4) at the respective
lateral ends.
3. The chute liner (10) as claimed in claim 2, wherein the protruded part (5) of one
block(l) can securely receive the depressed part (6) of another block (1) for mechanical
interlocking between the blocks.
4. The chute liner (10) as claimed in claim 2, wherein the gap between said protruded (5)
and depressed (6) parts is definite and predetermined for each block.
5. The chute liner (10) as claimed in claim 2, wherein a first thin film of rubber (7) is
provided in between vertical faces (3) at the front and rear ends of two adjoining
blocks(l) and a second thin film of rubber (8) is provided between the vertical faces (4)
at the lateral ends of two adjoining ceramic blocks (1).
6. The chute liner (10) as claimed in claims 2 and 3, wherein the protruded (5) and
depressed (6) parts are triangular or circular notches (5) and corresponding triangular
or circular grooves(6) respectively.

7. The chute liner (10) as claimed in claims 2 and 3, wherein the protruded (5) and
depressed (6) parts are rectangular notches (5) and corresponding rectangular
grooves(6) respectively.
8. The chute liner (10) as claimed in claims 1 and 5, wherein the first and second rubber
films (7, 8) and the blocks (1) are bonded with each other through chemical bonding.
9. The chute liner (10) as claimed in claim 1 wherein the blocks (1) are embedded in a
rubber matrix (2) which comprises at least a metal plate (9) for fixing the liner (10) on
to the chute wall through studs and the blocks (1) of two adjacent rows are arranged to
be asymmetric with each other.
10. The chute liner (10) as claimed in claim 9, wherein the metal back plate(9) is made of
iron or steel or other alloys of iron or aluminium.

ABSTRACT

A ceramic chute liner (10) comprising of a plurality of mechanically interlocked ceramic
blocks (1). The corresponding mechanically interlocked ceramic blocks (1) have rubber films
between them along respective adjoining surfaces such that, the ceramic blocks (1) are
bonded with each other with substantial strength and the impact force is substantially
reduced.