GB2040415A - Improvements in refractory lining units - Google Patents

Abstract

Refractory units for lining furnace walls each comprise a core 1 wrapped with refractory fibrous material 3, 4, preferably blanket material in strip form. The core 1 serves as a carrier for the fibrous material and can be designed to give the unit desired handling and lining construction properties, of basic shape, rigidity and size not obtainable with the fibrous material alone, whilst the fibrous material provides the required refractory thermal insulation properties. Securing means 2 for mounting the units in place are carried, directly or indirectly by the core. The unit may have a backing plate 7, and the units may be used to secure a refractory fibre blanket to a wall. <IMAGE>

Description

SPECIFICATION Improvements in refractory lining units This invention relates to refractory lining units for lining furnace wails, or like high temperature structures such as industrial ovens.

In general the invention provides means for lining a furnace wall with fibrous refractory blanket material in the form of units which can be handled and mounted in place to build up a lining.

According to the invention, refractory units for lining a furnace wali, orthe like, each comprise a core wrapped with refractory fibrous material, preferably blanket material in strip form as one layer or in multiple layers preferably laid crosswise, the core serving as a carrier for the fibrous material, so as to give to the unit desired properties of basic shape, rigidity and size, and the fibrous material providing the required refractory thermal insulation properties.

Each unit core may consist of or include one or more relatively large plates, or an open or closed box structure, through or from which extend securing means, such as one or more screw-threaded bolts, stems or anchors, e.g. hooks, which pass through the fibrous wrapping for attachment to a furnace wall directly or by intermediate means, such as backing plates, which are in turn secured to the furnace wall.

The wrapping of each core preferably consists of one or more strips of fibrous blanket material laid across a front face of the core and wrapped over the edges and across the back so that at least the front face and two opposite edges of the core are completely covered.

At the back of the core, the strip ends are held in place, such as by a clamping plate or by being tucked into a recess in the core, and may extend around or be penetrated by the means for securing the unit to a furnace wall.

The unit core may be wrapped around all its edges or some edges may be unwrapped but covered when mounted in abutment against wrapped edges of adjacent units when installed in a lining. Preferably, even for unwrapped core edges, the fibrous material extends beyond the core edges so that the core is completely within the overall extent of the wrapping.

The wrapped units may be of such relatively large size and modular shape, such as square, rectangular or hexagonal, that they can fit together in abutting relationship to cover the furnace wall.

Alternatively the units may be spaced over the furnace wall so as to serve not only as refractory lining members themselves, for the areas covered by their wrapping, but as securing means for a layer or layers of fibrous refractory material laid over the furnace wall and pinned in place by the units at suitable intervals. The wall lining in such case has spaced areas covered by the wrapped units and the intervening area covered by fibrous material extending over and covering the spaces between the units.

It will be appreciated that this enables a furnace to be lined with any thickness of fibrous material within the effective length of the securing means of the units.

The invention is illustrated by way of example on the accompanying drawings, in which: Fig. 1 is an axial section through a wrapped-core unit as provided by the invention.

Fig. 2 is a view similar to Fig. 1 showing alternative features.

Fig. 3 is a perspective view of a unit as shown in Fig. 1 mounted on a backing plate for furnace lining.

Fig. 4 is fragmentary elevation of a furnace wall lined by contiguous units, Fig. 5-is a view similar to Fig. 4 but showing a lining with spaced units holding intervening fibrous refractory material in place, and Figs. 6, 7 and 8 are sectional perspective views of other embodiments of refractory lining units in accordance with the invention.

As shown by Figs. 1 to 3, the units each comprise a refractory core plate 1 and a stem 2, provided by a screw-threaded bolt passed through a central hole in the core plate 1, and a refractory fibre wrapping of cross-laid blanket strip layers 3,4 applied across the face of the unit and meeting around the stem 2 at the back. The core plates 1 are shown as square but could be of other symmetrical polygonal shape and as many layers of fibrous wrapping may be used as required.

In Fig. 1 there is shown a wrapping retaining plate 5 with a nut 6, at the back of the unit. The plate 5 may be a refractory plate, to form a permanent part of the unit, or could be a temporary holding plate of card or wood for example, serving only to hold the fibre wrapping until the unit is installed in a furnace.

As shown in Fig. 2, the holding plate 5 could itself be backed by a layer of fibrous refractory material 7 held buy a plate or washer 8 and nut 9.

Units as shown by Figs. 1 and 2 may be used to line a furnace wall by mounting them closely sideby-side, to cover the wall area completely, and securing them in place by their stems engaged through a framework and held by nuts or other anchorage means.

The unit of Fig. 3 is similar to that of Fig. 1 but is mounted on a backing plate 10 of refractory or other material offset in two perpendicular directions from the wrapping of the unit and provided with hooks 11, or other anchorages, for fixing in place on a furnace wall.

Offsetting of the unit wrappings on their backing plates 10 ensures, as shown by Fig. 4, that the junctions between the units can be backed by refractory material in an installed lining so that there are no gaps in the refractory insulation of the lining as a whole.

An alternative way of using the units is shown by Fig. 5 in which the units art; spaced over a furnace wall and secure in place between them layers of fibrous refractory material 12 laid overthewall in strips or sheets.

A suitable fibrous refractory material is the ceramic fibre known as "TRITON KAOWOOL" (Trade Mark).

Other constructions of wrapped core units are shown by Figs. 6,7 and 8 and these may be used to form a lining in the manner described above.

In Fig. 6, an open-ended rectangular box core 13, which may be of metal or refractory material or of a non-refractory material, such as wood, in accordance with the temperature conditions of intended use, is wrapped in both directions by two layers of refractory fibrous blanket strip 3 and 4, the ends of the inner strip 4 being tucked into the open ends of the box core 13 and the ends of the outer strip 3 being held by engagement beneath tongues 14 on a bent sheet metal anchorage hook 15 secured to the box core 13.

The box core 13 could be replaced by a pair of plates.

In the construction of Fig. 7, a tray core 16, like a box with an open top and open sides, has tucked into opposite ends of the tray the ends of a strip 17 of refractory fibrous blanket material, of somewhat greater width than the width of the tray 16, and the strip ends are held in place buy a rectangular frame 18 pressed into the tray 16 so as to grip the ends of the strip.

A bent sheet metal double anchorage hook 19 is secured to the base of the tray 16 and projects from the back of the unit. The projection of the hook 19 may be relatively small so as to require compression of the wrapped-over ends of the strip 17 when the unit is attached to a furnace wall.

Fig. 8 shows how a unit core can be formed in part by a low-cost refractory material block 20 cemented to a core plate 21 and wrapped by a strip of fibrous material 22 with its ends clamped by a backing plate 23 held by a nut 24 on a screw-threaded anchorage stem 25 carried by the core plate 21.

In all constructions, the fibrous wrapping material may be strapped with self-adhesive tape, or other temporary binding, which preferably holds the fibrous material under some compression until the units are installed. The temporary binding may be designed to burn-off or break under use conditions, leaving the fibrous material to recover towards its uncompressed condition, subject to any heat shrinkage which might occur. By this means, gaps at the junctions of adjacent units installed as a lining can be avoided.

Claims (7)

1. A refractory unit, for lining furnace walls, comprising a core wrapped with refractory fibrous material, the core serving as a carrier for the fibrous material, so as to give to the unit desired properties of basic shape, rigidity and size, and the fibrous material providing required refractory thermal insulation properties.

2. A refractory unit according to Claim 1, in which the fibrous material is blanket material wrapped around the core in strip form as one layer or in mul tiple layers laid cross-wise.

3. A refractory unit according to Claim 1 or 2, in which securing means for mounting the unit in place are carried, directly or indirectly, by the core.

4. A refractory unit according to any foregoing claim, in which the core comprises one or more plates around which the fibrous material is wrapped and held in place at the back of the unit from which securing means project.

5. A refractory unit according to claim 4, in which a block of refractory material is carried by a backplate to form a core therewith.

6. A refractory unit according to any of claims 1 to 4, in which the core comprises a box, tray or like recessed structure in recesses in which ends of the fibrous material are held.

7. Refractory units substantially as described and illustrated.