Heat insulating module and method of assembly for use in a high temperature chamber

Disclosed is a heat insulating module and a method of making the same for use in lining a high temperature chamber. The module has a main body formed of layers of refractory fibers positioned side by side and impaled on at least one rigid tie member spaced inwardly of one lateral edge of all layers with the ends of the tie member secured to one leg of L-shaped mounting members with the other legs thereof extending outwardly beynd the end layers of the module and coplanar with the adjacent lateral edge of said layers. The layers may be interconnected by folding a unitary blanket of fibers and, in either assembly mode, the layers are held snugly compressed by at least one encircling tie band.

This invention relates to high temperature heat insulating linings, and 
more particularly to a unique and improved heat insulating module and 
method of making the same for installation in abutment with other similar 
modules to provide a high temperature lining for furnaces and the like 
high temperature chambers. 
BACKGROUND OF THE INVENTION 
Various proposals have been made heretofore for providing a furnace and the 
like high temperature chambers with an insulative lining avoiding the 
disadvantages of rigid refractory material such as bricks and cast 
components. Such proposals involve the use of refractory fibers formed 
into mats, slabs, blankets and other configurations. The refractory or 
ceramic fibers are customarily laid down in randomly arranged layers 
interbonded to one another at points of crossover. Typically, chambers 
insulated with refractory fibers operate in a temperature range of 1,600 
degrees to 2,800 degrees F. a satisfactory insulation assembly utilizing 
refractory fibers requires an insulation thickness of four to six inches 
or more. Blankets of such fibers are applied with the layers lying 
generally parallel to the chamber wall, serious problems are encountered 
including those of securing the blankets to the wall and particularly the 
problem of delamination and spalling or peeling off of successive surface 
layers resulting in a relatively short service life. To avoid these 
problems and others associated therewith it has been the practice to 
utilize a wide variety of arrangements in which the fiber blankets, one to 
two inches thick are secured to the chamber wall with the fiber layers 
lying in planes generally normal to the chamber wall. This avoids the 
serious delamination and spalling problems but presents other problems 
associated with the assembly of liner modules or components formed of 
multiple layers held assembled in side-by-side relation and provided with 
suitable heat resistant means for securing the assembly to the chamber 
wall. Another problem present in modules formed of layers of fibers held 
compressed against one another adjacent the outer or cold face of the 
module results in the inner or hot face being unrestrained and free to 
flare away from one another. This flaring tendency of the unrestrained 
layers is highly desirable when the modules are installed closely adjacent 
one another but can handicap the installation operation because 
interfering with the workman's access to fasteners securing the module to 
the chamber wall. Additionally the flaring edges of the end layers present 
packaging and stowage problems prior to installation and these unprotected 
edges are exposed to handling damage. 
Patents in this art dealing with these problems and proposing a variety of 
solutions include: Sauder et al U.S. Pat. No. 3,819,468; Ballaz et al U.S. 
Pat. No. 3,832,815; Brady U.S. Pat. No. 3,854,262; Monaghan U.S. Pat. No. 
3,892,396; Sauder et al U.S. Pat. No. 3,940,244; Byrd U.S. Pat. No. 
3,952,470; Byrd U.S. Pat. No. 4,001,996; Byrd U.S. Pat. No. 4,012,877; 
Byrd U.S. Pat. No. 4,103,469; Myles U.S. Pat. No. 4,120,641; Byrd U.S. 
Pat. No. 4,123,886; Cunningham et al U.S. Pat. No. 4,218,962; Severin et 
al U.S. Pat. No. 4,287,839; Hounsel et al U.S. Pat. No. 4,381,639; 
European Patents Publication No. 0,018,677 and U.K. patent application No. 
2,004,626 A. 
The two Sauder patents propose a complex module assembly formed of a 
multiplicity of individual strips of refractory fiber mounted along one 
edge to an expanded metal backing or held assembled to a backing layer of 
fibers by means of a complex series of tie wires criss-crossing one 
another. The several Byrd patents show different techniques for folding a 
ceramic blanket with certain folds embracing an elongated anchor member 
provided with tang means protruding outwardly through the folds with the 
outer end clenched to an elongated mounted strip securable to a furnace 
wall. 
The Cunningham and Hounsel patents show closely related variants of the 
several Byrd teachings. Bolus and Brady both propose modules composed of 
separate strips of refractory fibers required to be assembled individually 
in side-by-side relation and held assembled by a plurality of pins on 
which all strips are impaled and secured to retain members at the opposite 
ends of the pins. Brady's clamping pins are staggered relative to one 
another and the retaining members are secured to a mounting plate 
coextensive with the outer edges of the strips and securable to a furnace 
chamber, whereas Balaz extends his pins through eye bolts utilized to 
clamp the module to the chamber wall. Monaghan secures one end of L-shaped 
mounting hooks to the chamber wall and having a pointed leg extending 
upwardly and spaced from the wall. Individual strips of insulating fibers 
are then impaled over the upright legs. Miles places a multiplicity of 
ceramic fiber strips in side-by-side relation and bonds one lateral edge 
to an expanded metal mounting strip. The module is then secured to the 
wall by round ended buttons forcibly inserted into respective expanded 
metal openings. 
Severin et al, proposes a pleated ceramic fiber blanket utilizing a 
multiplicity of components including a channel shaped baseplate, a pair of 
rods piercing all pleats and having their ends anchored in tabs secured to 
a base plate provided at its corners with J-shaped suspension bolts 
engageable with pairs of rods mounted on the interior of a furnace wall. 
The European publication extends ceramic tubes through adjacent layers of 
refractory fibers. These tubes also pierce one end of suspension ceramic 
tubes having their other ends projecting beyond the cold edges of the 
layers and serving to seat hook members engageable with the structural 
elements of the chamber wall. The outermost edges of the layers are also 
bonded to one face of large ceramic baseplate. Modules formed by this 
technique are sufficiently large to extend across the width of a furnace 
wall. 
SUMMARY OF THE INVENTION 
This invention avoids the complexities and costly manipulative operations 
required to manufacture and assembly prior heat insulating modules and 
equipped with expedients for mounting them on a chamber wall. These 
advantages are achieved by impaling a multiplicity of similar layers of 
refractory fiber on either one or a pair of tie members spaced inwardly of 
one lateral edge of the layers. These tie members pierce all layers and 
their ends are secured to one leg of separate L-shaped mounting members 
thereby holding all layers compressed against one another and the other 
leg of the mounting members lying coplanar with the cold wall of the 
module and projecting away from one another. All layers are also 
preferably snugly encircled by tie bands effective to hold the entire 
width of the layers equally compressed for greater protection and ease of 
handling and mounting of the modules against a chamber wall. These tie 
bands are subject to destruction when the chamber is first placed in 
operation and then allow the hot edges of the layers to expand against the 
layers of neighboring modules to provide a continuous gapless lining for 
the chamber. 
Accordingly, it is a primary object of this invention to provide a unique, 
low cost, simplified heat insulating module as a lining for a high 
temperature chamber. 
Another object of the invention is the provision of an improved method of 
assembling a heat insulating module formed of layers of refractory fibers 
traversed near the cold face thereof with tie members secured to module 
mounting members and wherein the layers are held snugly compressed by 
encircling tie bands prior to use in a furnace chamber. 
Another object of the invention is the provision of a high temperature 
insulating module formed from a folded blanket of refractory fibers held 
snugly compressed by encircling destructible band means and impaled by tie 
members adjacent the cold face of the module secured at their ends to 
L-shaped module mounting members. 
These and other more specific objects will appear upon reading the 
following specification and claims and upon considering in connection 
therewith the attached drawing to which they relate.

Referring to the drawing, there is shown an exemplary embodiment of the 
invention module designated generally 10. The module may be of various 
configurations but as there shown it is square and has a main body formed 
from a single unitary blanket 11 of superimposed layers of refractory 
ceramic fibers. Commercially available blankets of such fibers typically 
provide long service life under temperature conditions as high as 2,600 
degrees F. or higher, the fibers being arranged randomly in layers 
parallel to the blanket surfaces. Such blankets are of uniform thickness 
and folded into similar pleats with the pleat layers held compressed 
against one another and the fiber layers lying generally normal to the two 
parallel faces 12 and 13. The folds between adjacent layers forming face 
12 are exposed to the high temperature of the chamber being insulated and 
is known as the hot face of the module whereas the folds on the other face 
13 face toward the chamber wall and constitute the cold face of the 
module. Preferably the opposite ends of the blanket lie coplanar with the 
cold face of the completed module. 
The blanket is readily folded into accordion pleats by placing the 
outstretched strip of blanket material over the top edges of a series of 
upright partition plates following which portions of the blanket between 
the upper edges of adjacent plates are pressed downwardly between adjacent 
pairs of plates in succession until all pleats have been formed. The 
partition plates are slotted downwardly from their upper edges to a point 
near but spaced upwardly from the lower edges of the partition plates. At 
least one, and preferably two, tie members are then pressed through the 
layers of the folded blanket. This operation is facilitated by inserting a 
pointed pilot member in the leading end of a tubular tie member. The 
semifinished module is then lifted clear of the partition plates and a 
pair of bands 15 are assembled about the layers of ceramic fibers to hold 
all layers snugly compressed against one another. Any suitable banding 
material may be employed which will be subject to destruction as the 
chamber in which the module is installed is being brought up to an 
operating temperature. However, prior to that time, all layers are 
preferably held firmly and snugly compressed such as in the rectangular 
configuration shown in FIG. 1. 
The opposite ends of the tubular tie members 17, 17 project from the 
opposite ends of the module and are assembled to angle iron mounting 
members 18 with the upright leg 18a of each iron assembled over the 
adjacent end of the tie members and secured in place as by expansion or 
outward upsetting of each end 20. The other legs 18b extend outwardly away 
from one another in a plane generally coplanar with the cold face 13 of 
the module. These legs are provided with at least one opening 21 to 
receive mounting fasteners for the module. 
A convenient form of fastener comprises studs 22 having an axial tip 23 at 
one end to facilitate its assembly to a metallic furnace wall 24 by 
electric resistance welding. The adjacent end of the stud, is here shown 
provided with outwardly projecting flutes 25 of triangular cross section 
with their pointed outer crests lying outwardly of the remaining main body 
of the studs. These studs are assembled to the interior of the furnace 
chamber in a desired pattern such that the module mounting members 18 can 
be readily installed thereover. Once the module is in place over the studs 
threaded nuts 26 are assembled over the smaller outer end of the studs and 
then forcibly pressed downwardly over the flutes 25 thereby pressing the 
mounting members 18 snugly against the furnace chamber. The hardened 
flutes 25 cut into the nut threads and provide a high strength fastener 
assembly adequately strong to hold the entire lightweight module 10 firmly 
installed. A single fastener stud at each end of the module is found 
satisfactory for smaller modules but larger module assemblies may employ a 
pair of studs at each end. 
Bands 15 of plastic or other nonmetallic material are installed during the 
pleating operation and serve to hold the ceramic fiber material compressed 
particularly adjacent the hot face at all times prior to actual use of the 
modules in the furnace and particularly while being installed. This 
provides the installer with unobstructed visual access to studs 22 during 
installation. Many users install the modules parquet fashion so that the 
mounting members of adjacent modules do not interfere with one another 
during installation. Once the chamber is placed in use bands 15 fail and 
are destroyed as the temperature rises. This permits the hot face to 
expand into firm contact with adjacent modules to provide a gapless and 
continuous high temperature lining of insulation material. 
While the particular heat insulating module and method of assembly for use 
in a high temperature chamber herein shown and disclosed in detail is 
fully capable of attaining the objects and providing the advantages 
hereinbefore stated, it is to be understood that it is merely illustrative 
of the presently preferred embodiment of the invention and that no 
limitations are intended to the detail of construction or design herein 
shown other than as defined in the appended claims.