GB2039829A - An Insulating Block - Google Patents

An Insulating Block Download PDF

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Publication number
GB2039829A
GB2039829A GB7900876A GB7900876A GB2039829A GB 2039829 A GB2039829 A GB 2039829A GB 7900876 A GB7900876 A GB 7900876A GB 7900876 A GB7900876 A GB 7900876A GB 2039829 A GB2039829 A GB 2039829A
Authority
GB
United Kingdom
Prior art keywords
insulating
wall
adhesive
blocks
bonded
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7900876A
Other versions
GB2039829B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Isolite Babcock Refractories Co Ltd
Original Assignee
Isolite Babcock Refractories Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Isolite Babcock Refractories Co Ltd filed Critical Isolite Babcock Refractories Co Ltd
Priority to GB7900876A priority Critical patent/GB2039829B/en
Publication of GB2039829A publication Critical patent/GB2039829A/en
Application granted granted Critical
Publication of GB2039829B publication Critical patent/GB2039829B/en
Expired legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B18/00—Layered products essentially comprising ceramics, e.g. refractory products
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
    • B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
    • B32B5/24—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer
    • B32B5/26—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed one layer being a fibrous or filamentary layer another layer next to it also being fibrous or filamentary
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B19/00—Layered products comprising a layer of natural mineral fibres or particles, e.g. asbestos, mica
    • B32B19/04—Layered products comprising a layer of natural mineral fibres or particles, e.g. asbestos, mica next to another layer of the same or of a different material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/04—Interconnection of layers
    • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B30/00—Compositions for artificial stone, not containing binders
    • C04B30/02—Compositions for artificial stone, not containing binders containing fibrous materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/02—Shape or form of insulating materials, with or without coverings integral with the insulating materials
    • F16L59/028—Composition or method of fixing a thermally insulating material
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
    • F27D1/00—Casings; Linings; Walls; Roofs
    • F27D1/0003—Linings or walls
    • F27D1/0006—Linings or walls formed from bricks or layers with a particular composition or specific characteristics
    • F27D1/0009—Comprising ceramic fibre elements
    • F27D1/002—Comprising ceramic fibre elements the fibre elements being composed of adjacent separate strips
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2307/00—Properties of the layers or laminate
    • B32B2307/30—Properties of the layers or laminate having particular thermal properties
    • B32B2307/304—Insulating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B2607/00—Walls, panels
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
    • C04B2237/32—Ceramic
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
    • C04B2237/32—Ceramic
    • C04B2237/38—Fiber or whisker reinforced
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/76—Forming laminates or joined articles comprising at least one member in the form other than a sheet or disc, e.g. two tubes or a tube and a sheet or disc

Abstract

Insulating blocks of fibrous material and rectangular or semi- cylindrical in shape, obtained by bonding together layers of ceramic fibre blankets using an adhesive. Such insulating blocks are secured to the surface of the furnace wall such that the bonded surfaces between adjacent ceramic fibre blanket layers are perpendicular to the wall surface. By using such blocks which are easy to handle, it is possible to facilitate, and reduce time required for, construction of an insulating wall.

Description

SPECIFICATION An Insulating Block This invention relates to an insulating block and in particular insulating materials blocks used for insulating furnaces.
Ceramic fibre blanket (or felt) commonly used as an insulating material is usually manufactured in continuous form, and can be cut to suitable lengths and rolled for shipment as shown in Fig.
9. When used for lining a furnace it is cut to suitable lengths, the pieces then being applied one by one, in layers, on the furnace wall and bonded or otherwise secured to the furnace wall.
This is described in Japanese Patent Specification No. 39825/1971 and No.
14085/1878.
However, the ceramic blanket is very light and soft (like cotton wool,) so that it is likely to be broken or stretched unless it is handled very carefully, hence, to fit insulation can be very time consuming. In addition, the blanket is usually secured to the furnace wall using bolts, nuts or rods, made of heat-resistant alloy. The use of such mounting members is not only time consuming but also requires the furnace outer wall to be sufficiently strong to support the weight of these mounting members.
When using such ceramic fibre blanket strip, therefore, it has been applied in long lengths so as to increase the efficiency of installation. However, the longer the length the greater the thermal contraction so that gaps are likely to occur between adjacent lengths. The installation efficiency and performance of installation surface go counter to each other.
According to this invention we prepare an insulating block comprising layers of ceramic fibre blanket which are bonded together by an adhesive. The invention also includes an insulating wall built of such insulating blocks.
The insulating blocks according to this invention consists (apart from adhesive) of layers of ceramic fibre blanket and is ready to handle and readily capable of processing.
Also the insulating block does not require a mounting member but can be simply and quickly applied and has sufficient insulation property.
Embodiments of this invention will now be described by way of example with reference to the accompaning drawings of which: Fig. 1 is a perspective view of an insulating block according to the invention; Fig. 2 is a perspective view of a piece of ceramic fibre material forming part of the insulating block shown in Fig. 1; Fig. 3 is a perspective view of another embodiment of the insulating block; Fig. 4 is a detailed perspective view of the embodiment of Fig. 1; Fig. 5 shows an insulating wall according to the invention; Fig. 6 is a cross-section taken along line VI-VI in Fig. 5; Fig. 7 is a cross-section similar to Fig. 6 but showing another embodiment of the insulating wall; Fig. 8 is a plan view of the embodiment of Fig.
7; and Fig. 9 is a perspective view of a commercially available ceramic fibre blanket.
A ceramic fibre blanket or felt as shown in Fig.
9 is cut into lengths la as shown in Fig. 2, for instance 1 5 to 60cm and a width of 2.5 to 30cm, and such lengths of blanket are stacked together with the contact surfaces l b of adjacent lengths firmely bonded together by an organic or inorganic adhesive, thus forming a rectangular block of fibrous insulating material 1. As another example, pieces la we cut from annular disc-like pieces of blanket pieces and bonded using an adhesive, one upon the other in layers to produce a semi-cylindrical block.
The adhesive used may be a heat-resistant adhesive containing refractory cement or the like or what is gasified and burnt away at the working temperature. The block of insulating material may be rectangular or semi-cylindrical as described, or any other convenient shape.
With the above structure of the block, in which the contact surface of adjacent pieces are bonded together by adhesive, the surfaces bonded by the adhesive serve as core, and the insulating material is as strong as if it incorporated cores.
Thus, not only is handling facilitated, but also the block may be readily cut using a knife to suit a particular location. Further, the installation of the insulating material can be achieved much more quickly than with conventional materials such as shown in Fig. 9.
Figs. 4 to 6 show an embodiment, in which a furnace wall is insulated using blocks of fibrous insulating material as shown in Fig. 1. Each block has on its surface 1c transverse to the bonding surfaces ib, a layer of refractory adhesive 2 along the four sides and also the bonded surfaces of adjacent pieces 2, and the individual blocks of fibrous insulating material 1 are secured by the refractory adhesive layers 2, in a mosaic form to a metal net 4 mounted on the inner surface of a shell 3.
Where the insulating materials are directly bonded to the shell 3, the adhesion obtained is inferior, but by bonding them via metal latch or metal net they can be securely bonded since the wires of the metal do not become embedded in the refractory adhesive 2 before it sets.
They may be bonded to the surface of an existing fire brick, dense fire brick, refractory castable and refractory plastics material structures instead of bonding them to metal lath or metal nets.
Figs. 7 and 8 show another embodiment of the invention, in which the insulating block is secured to the outer periphery of the pillar-like body. In this embodiment, the blocks of fibrous insulating material 1 are semi-cylindrical formed by stacking and bonding together in layers pieces of ceramic fibre blanket la as shown in Fig. 3. They may have on their inner surface id refractory adhesive layers 2 similar to those described with reference to Fig. 4 and then they are stacked one on top of the other around the entire outer periphery of a refractories structure or refractory mortar 6 in contact with a skid pipe 5 cooled with water passed therethrough, and there bonded together thus forming an insulating wall.
Layers of ceramic fibre blanket could be stacked and bound together by wires passing transversly through the various layers of ceramic fibre blanket but this is a time consuming operation involving additional expense.
Alternatively, the layers may be bound together by winding tape around the stack or by wrapping the stack in paper or polyethylene sheets.
However, neither of these proposals is acceptable since the former alternative tends to crush the corners of the stack so that gaps are formed when building an insulating wall and, in the latter alternative, the ceramic fibre layers are likely to be broken because they are soft. Also this method does not permit a wide choice of shapes. Further, none of the above methods produce a body which may be cut. These problems are avoided by the present invention, the insulating block according to the present invention being easily handled and readily installed.Also, when the ceramic fibres in the layers of ceramic fibre blanket are made to extend mainly in a direction normal to the thickness of the layer the tensile strength of the block in this direction is considerable and the block is preferably disposed such that the fibre blanket is at right angles to the surface of a wall to be insulated with one end bonded thereto, so effectively utilizing the tensile strength. Thus, there is no possibility of the blocks peeling layer by layer and the weight of the material can be supported by itself, permitting an insulating wall to be built cheaply and without the need for any mounting member. Also, since the layers of ceramic fibre blanket are already bonded to one another as described above, the installation is simpler, and quicker than for the conventional method of assembly of separate pieces of blanket in situ.
Further, since the materials are bonded to the wall surface constituted by metal latch, bricks, mortar, etc., by strips of refractory adhesive 2 spaced apart in the direction in which the fibres themselves extend, differential thermal expansion and contraction between wall surface and ceramic fibre blanket bonded thereto is accommodated. Furthermore, since the strips adhesive 2 are transverse to layers of ceramic fibre blanket forming the block, the strength of the bonded surface reinforced by the adhesive on the layers la can be effectively utilized to ensure reliable bonding to the wall surface. Moreover, since no mounting member is necessary, the heat insulation property of the ceramic fibres is more effective than in the prior art construction.
Depending upon the desired thickness an insulating wall may be built using several layers of insulating blocks according to this invention.

Claims (17)

Claims
1. An insulating block comprising layers of ceramic fibre blanket which are bonded together by an adhesive.
2. An insulating block according to Claim 1, which is rectangular.
3. An insulating block according to Claim 1, which is semi-cylindrical.
4. An insulating block according to any one of Claims 1 to 3, wherein the ceramic fibre blanket has a length of 15 to 60cm and a width of 25 to 30cm.
5. An insulating block according to any one of Claims 1 to 4, wherein the adhesive comprised refractory cement.
6. An insulating block according to any one of Claims 1 to 5, wherein the adhesive is gasified and burnt away at the working temperature.
7. An insulating block constructed and arranged substantially as herein before described with reference to and as illustrated in Figs. 1 to 4 of the accompanying drawings.
8. An insulating wall built of insulating blocks according to any one of Claims 1 to 7.
9. An insulating wall according to Claim 8 wherein the blocks are bonded, by an adhesive, to the surface of a wall to be insulated.
10. An insulating wall according to Claim 9 and comprising joining means between the adhesive layers and the wall surface.
1 An insulating wall according to Claim 10 wherein the joining means is a metal net.
12. An insulating wall according to claim 10, wherein the joining means is a metal lath.
13. An insulating wall according to any one of Claims 9 to 12, wherein the wall surface comprises refractory bricks, castable and plastics.
14. An insulating wall according to Claim 9, wherein the blocks in the wall are staggered relative to one another.
15. An insulating wall according to any one of Claims 9 to 14, wherein each of the insulating blocks has strips of adhesive at right angles to the bonded surfaces along the four sides and also along the bonded surfaces.
16. An insulating wall according to any one of Claims 9 to 13, wherein the insulating blocks are semi-cylindrical and are built and bonded together into a wall enclosing the outer cylindrical surface of a skid pipe which is covered by refractory material.
17. An insulating wall constructed and arranged substantially as hereinbefore described with reference to and as illustrated in Figs. 1 to 8 of the accompanying drawings.
GB7900876A 1979-01-10 1979-01-10 Insulating block Expired GB2039829B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB7900876A GB2039829B (en) 1979-01-10 1979-01-10 Insulating block

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB7900876A GB2039829B (en) 1979-01-10 1979-01-10 Insulating block

Publications (2)

Publication Number Publication Date
GB2039829A true GB2039829A (en) 1980-08-20
GB2039829B GB2039829B (en) 1983-09-01

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2508594A1 (en) * 1981-06-27 1982-12-31 Promat THERMAL PROTECTION SHEATH, FOR EXTENDED PARTS OF A STRUCTURE
FR2558243A1 (en) * 1984-01-13 1985-07-19 Lafarge Refractaires OVEN COMPARTMENT COMPRISING A PASSAGE FOR GAS FROM A BURNER AND PROCESS FOR OBTAINING THE SAME
EP0199958A1 (en) * 1985-03-29 1986-11-05 Bloom Engineering (Europa) GmbH Refractory cover for tubes in preheating furnaces
EP0483743A2 (en) * 1990-11-02 1992-05-06 Chamottewaren- und Thonöfenfabrik Aug. Rath Jun. Aktiengesellschaft Fiber burner brick and burner with such a fiber burner brick
EP2072087A1 (en) * 2007-12-19 2009-06-24 Freyssinet Mattress for fire protection, associated method
EP3608579A4 (en) * 2017-04-07 2021-01-13 Public Joint Stock Company "Machine-Building Plant "Ziopodolsk" Reinforced removable thermal insulation

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2508594A1 (en) * 1981-06-27 1982-12-31 Promat THERMAL PROTECTION SHEATH, FOR EXTENDED PARTS OF A STRUCTURE
FR2558243A1 (en) * 1984-01-13 1985-07-19 Lafarge Refractaires OVEN COMPARTMENT COMPRISING A PASSAGE FOR GAS FROM A BURNER AND PROCESS FOR OBTAINING THE SAME
EP0151543A1 (en) * 1984-01-13 1985-08-14 Kerlane Oven part constituting a duct for the exhaust gases of a burner and process for its fabrication
EP0199958A1 (en) * 1985-03-29 1986-11-05 Bloom Engineering (Europa) GmbH Refractory cover for tubes in preheating furnaces
EP0483743A2 (en) * 1990-11-02 1992-05-06 Chamottewaren- und Thonöfenfabrik Aug. Rath Jun. Aktiengesellschaft Fiber burner brick and burner with such a fiber burner brick
EP0483743A3 (en) * 1990-11-02 1992-10-28 Chamottewaren- Und Thonofenfabrik Aug. Rath Jun Aktiengesellschaft Fiber burner brick and burner with such a fiber burner brick
US5348468A (en) * 1990-11-02 1994-09-20 Chamottewaren-Und Thonofenfabrick Aug. Rath Jun. Aktiengesellschaft Fiber brick and burner with such fiber brick
EP2072087A1 (en) * 2007-12-19 2009-06-24 Freyssinet Mattress for fire protection, associated method
FR2925343A1 (en) * 2007-12-19 2009-06-26 Freyssinet Soc Par Actions Sim MATTRESS FOR FIRE PROTECTION, ASSOCIATED METHOD.
US8007888B2 (en) 2007-12-19 2011-08-30 Freyssinet Fire protection blanket and associated method
EP3608579A4 (en) * 2017-04-07 2021-01-13 Public Joint Stock Company "Machine-Building Plant "Ziopodolsk" Reinforced removable thermal insulation

Also Published As

Publication number Publication date
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Date Code Title Description
PE20 Patent expired after termination of 20 years

Effective date: 19990109