Interlocking refractory segments

Interlocking refractory segments for use in insulating pipes and the like are each formed with wire anchors embedded therein. The anchors have exposed ends at each side edge of the refractory segment. The exposed ends of one segment are formed so as to interlock with the exposed ends of a second segment so as to secure the segments in a fixed position extending around the pipe to be insulated. Preferably, the exposed ends of one segment are shaped to provide a hook configuration and the exposed ends of the anchor of another segment are shaped to provide an eye configuration for receiving the hook shaped configuration.

FIELD OF INVENTION 
This invention relates to refractory components for use in insulating pipes 
and the like. 
PRIOR ART 
Refractory segments used for the purposes of insulating pipes in hostile 
environments such as those of the steel manufacturing industry are of two 
distinct types. 
The first type, which is suited for the most hostile environments is one in 
which a body of refractory material has a metallic anchor member embedded 
therein. The metallic anchor member is welded to the member which it is 
intended to insulate in use. An example of this type of refractory segment 
is described in my prior U.S. Pat. No. 4,134,721 dated Jan. 16, 1979. 
In the other type of refractory segment which is presently available, the 
body of the refractory material of each segment is shaped to interlock 
with the body of the refractory material of another segment to be retained 
by means of this interlock on the member which is to be insulated. The 
second type of refractory segment is not suitable for many hostile 
environments where the segments are subjected to severe vibrations, which 
conditions exist in many steel making installations. Refractory material 
is inherently brittle and is not capable of withstanding shock loading. 
For this reason, interlocking refractory segments are generally made from 
ceramic fibers which serve to increase fracture resistence, however this 
structure is not sufficiently rugged to withstand the hostile environment 
in which castable refractories are commonly used. 
One of the principal difficulties which is experienced with the refractory 
segments of the type which are welded as previously described, is that the 
installation of these segments is labour intensive, requiring the services 
of an individual skilled in the installation of refractory materials and a 
welder. 
I have found that the installation of refractory sgments can be greatly 
simplified by modifying the exposed ends of the anchor members to permit 
two segments to be interlocked by means of the exposed ends of the anchor 
members, thereby to retain the segments on the pipe which is to be 
insulated without requiring welding of the anchor members to the pipe. 
SUMMARY OF INVENTION 
According to one aspect of the present invention, there is provided in a 
refractory segment having a body of refractory material, in which anchor 
means is embedded, said anchor means having exposed ends at each 
longitudinal side face of said segment, the improvement wherein said 
exposed ends of said anchor means are adapted to interlock with exposed 
end of anchor means of a further refractory segment to secure said first 
mentioned refractory segment and said further refractory segment in a 
position encircling the member to be insulated in use. 
According to a further aspect of the present invention, there is provided, 
in a refractory assembly which comprises at least two segments adapted to 
encircle a member which is to be insulated, each segment comprising a body 
of refractory material in which anchor means is embedded, said anchor 
means providing at least one exposed end at each longitudinal side face of 
each segment, the improvement wherein said longitudinal side face is of at 
least one of said segments are set back to expose said exposed ends for 
engagement with the exposed ends of the other of said segments, the 
exposed ends of the anchor means of one of said segments being adapted to 
interlock with the exposed ends of the anchor means of the other of said 
segments, thereby to retain said segments in a position encircling the 
member to be insulated in use. 
According to a further aspect of the present invention, there is provided 
an interlocking refractory assembly for use in insulating metal pipes 
which comprises, first and second refractory segments, each comprising a 
body of refractory material having an arcuate shaped inner face forming a 
pipe receiving recess and a pair of longitudinal side edges, the 
longitudinal side edges of a first segment being disposed opposite the 
longitudinal side edges of a second segment to provide a pair of opposed 
side edges when said segments are operably positioned about a pipe in use, 
at least one of said side edges of each pair of opposed side edges having 
a set back section, anchor means embedded in the body of each segment, 
said side edges of each pair of opposed side edges having a set back 
section, anchor means embedded in the body of each segment, said anchor 
means having at least one exposed end at each longitudinal side edge, the 
exposed ends of said anchor means of each segment in which a set back is 
formed being disposed within said set back, the exposed ends of the anchor 
means of one segment being adapted to interlock with the exposed ends of 
the anchor means of the other segment, and said set back at each pair of 
opposed side edges being proportioned to permit longitudinal relative 
movement between said segments to effect interlocking when said segments 
are positioned about a pipe in use. 
PREFERRED EMBODIMENT 
The invention will be more clearly understood after reference to the 
following detailed specification read in conjunction with the drawings 
wherein: 
FIG. 1 is a pictorial view of a refractory segment having an anchor member 
provided therein which has exposed ends shaped to provide an interlocking 
eye. 
FIG. 2 is a pictorial view of a refractory segment having an anchor 
assembly embedded therein in which the exposed ends have a hook 
configuration. 
FIG. 3 is a pictorial side view of a refractory assembly mounted on a pipe 
member which is to be insulated in accordance with an embodiment of the 
present invention. 
FIG. 4 is an enlarged detail view of the interlocking structure of the 
anchor mechanisms of FIG. 3. 
FIG. 5 is a pictorial view of a refractory segment constructed in 
accordance with a further embodiment of the present invention. 
FIG. 6 is a plan view illustrating an alternative interlocking 
configuration. 
FIG. 7 is a side view of the interlocking configuration of FIG. 6.

With reference to FIGS. 1 and 2 of the drawings, reference numeral 10 
appears generally to a first refractory segment and the reference numeral 
20 refers generally to a second refractory segment. The refractory 
segments 10 and 20 are made from a body 12 of castable refractory material 
such as manufactured by Plibrico Canada Limited. The body 12 may have 
reinforcing metal needles dispersed therethrough. A pair of anchoring 
members 14 of a first type bar embedded in the body 12 of the first 
segment 10, and a second pair of anchor members 16 are embedded in the 
body 12 of the second refractory segment 20. The anchor members each 
consist of a coiled wire 18 and a rod 22. The rod 22 is secured as by 
welding to several of the turns of the coil 18 thereby serving to maintain 
the various turns of the coil 18 in an open configuration to provide good 
anchoring within the body 12. An eye 24 is formed at each end of each rod 
22. The longitudinal side faces 26 of the first segment 12 are each formed 
with a set back 28. The depth of the set back 28 increases progressively 
from the outer end thereof toward the inner end such that the setback is 
wedge-shaped and when it is subsequently plugged, the plug is wedged in 
the recess formed by the set back. 
The second segment 20 differs from the first segment 10 in that the 
longitudinal side faces 26 are not formed with a set back, and the 
opposite ends of the anchor rods 22 are formed with a hook shaped element 
30. 
In use, the segment 10 is positioned around the pipe 32 which is to be 
insulated as shown in FIG. 3 of the drawings, and the segment 12 is 
positioned with the longitudinal end faces 26 of the two segments 
abutting, and the hook shaped ends 30 of the anchor rods 22 of the second 
segment 20 projecting into the set back 28. 
By moving the first segment 10 in the direction of the arrow A and or the 
second segment 20 in the direction of the arrow B, the hook shaped ends 30 
are caused to enter the eye shaped ends 24 as shown in FIG. 4 of the 
drawings such that the first and second segments are maintained in an 
interlocked relationship so as to be self supported on the pipe 32. The 
fit between the hook shaped ends 30 and the eye 24 of each interlocking 
anchor assembly is such as to permit a substantial degree of freedom of 
movement to accommodate variations in the diameter of the pipe 32. Such 
variations in diameter frequently occur as a result of the accumulation of 
scale on the pipe 32 in many steel plant applications. 
From the foregoing it would be apparent that refractory segments having 
interlocking anchor mechanisms of the type described above can be 
assembled with ease by personnel skilled in the installation of refractory 
material without requiring the assistance of a skilled welder. After the 
interlocking refractory segments have been assembled as previously 
described, the gap formed by the set back 28 is filled with a rammable 
refractory material, as is any gap which may be formed between the 
oppositely disposed longitudinal side faces 26 of the assembled segments. 
Various modifications of the present invention will be apparent to those 
skilled in the art. 
As shown in FIG. 5 of the drawings, a refractory segment 50 may be formed 
with set backs 52, and each longitudinal side face 54. The ends 56 of the 
anchor members 58 may be hook members which are angularly offset as shown 
in FIGS. 5 and 6 whereby two substantially identical segments 50 may be 
interlocked with one another, thereby dispensing with the need to provide 
two distinctly different refractory segments. By laterally inclining the 
hook shaped elements 56, it is merely necessary to invert one segment 56 
prior to installation so that it is oriented to cause the oppositely 
disposed hook shaped members 56 to interlock with one another when mounted 
as previously described with reference to FIG. 3 of the drawings. 
These and other modifications of the present invention will be apparent to 
those skilled in the art. As previously indicated, the refractory segments 
10 and 20 may be made from a high strength castable refractory material 
such as which may be fortified by a measured mixture of stainless steel 
fibres interlaced therewith to enhance flexural strength, and maximize 
resistance to mechanical abuse, spalling and thermoshock. The anchor 
assemblies made each consist of a coiled wire having a thickness of 0.109 
inches and a coil diameter of 1.25 inches and a coil pitch of 0.5 inches. 
The rods 14 are preferably made from stainless steel and a typical rod is 
made from 310 stainless steel and has a 0.25 inch diameter. 
From the foregoing it will be apparent that the refractory segments 
constructed in accordance with the present invention are inexpensive to 
manufacture and are capable of being self supporting without requiring the 
services of a welder in their installation. These and other advantages of 
the refractory segments of the present invention will be apparent to those 
skilled in the art.