GB2179127A

GB2179127A - Kiln cars

Info

Publication number: GB2179127A
Application number: GB08517172A
Authority: GB
Inventors: John Elliott
Original assignee: Acme Marls Ltd
Current assignee: Acme Marls Ltd
Priority date: 1985-07-05
Filing date: 1985-07-05
Publication date: 1987-02-25
Also published as: CN1017183B; GB8517172D0; CN86105634A; EP0208249A1; DE3665929D1; EP0208249B1

Description

1 GB2179127A 1

SPECIFICATION

Kiln cars Description of the Invention This invention relates to kiln cars of the type employed for carrying articles of ceramic ware through a kiln during a firing process. Such kiln cars normally comprise a non-refractory trolley which supports a refractory structure including at least a base which protects the trolley and carries the ware to be fired, the latter often being supported on a refractory superstructure which is built up on the base.

To reduce loss of heat due to thermal cycl ing, it is desirable to minimise the thermal mass of the base, for example as described in our European Patent specification No.

0024037.

To facilitate mechanical loading of ware to 85 be fired, it has been proposed to use a super structure which incorporates removable shelves, or bats, on which the ware is placed prior to assembly of the loaded bat with the superstructure. However, to ensure the necessary degree of stability for the superstructure, both when the ware-carrying bats are in place and when they are absent, it has been found necessary to incorporate into the permanent superstructure transverse members which interconnect vertical members which afford supports for the removable bats.

In one arrangement, as described in our U.K. Patent specification No. 1518052 for example, the superstructure incorporates a vertical wall running along the longitudinal centre line of the kiln car. Vertical members are secured to such central wall at spaced longitudinal intervals and extend outwardly in mutually parallel relation to define bays for the reception of removable bats on supporting ledges carried by the vertical members. This arrangement has the disadvantage that the central wall divides the car into two lateral zones, so that loading of the bats has to be carried out from opposite sides of the kiln car. This requires the use of either two sets of loading apparatus, or specially designed loading apparatus which can serve both sides of the kiln car either simultaneously or in sequence. However, such apparatus is undesirably costly and may often be too bulky for practical use.

In another arrangement, as described in U.K.

Patent 1421504 for example, the superstructure includes superposed column elements which are interconnected by fixed horizontal bats and also afford vertically spaced supports for additional, removal bats. Whilst this arrangement is such that loading may be carried out from only one side of the kiln car, it is not well suited to mechanical loading since the fixed bats cannot effectively be utilised to support ware, unless hand-loaded, Addition- ally, the minimum clearance which must be available beneath a removable bat in order to accommodate supporting parts of the loading mechanism causes a relatively large volume of space above such fixed bats to be unused, thereby significantly reducing the load carrying capacity of the refractory structure.

Both of these examples suffer from the further disadvantage that the superstructure is of relatively massive construction, and hence gives rise to significant energy loss due to thermal cycling.

The object of the invention is to provide a refractory structure for a kiln car which affords an improvement over such prior proposals in one or more aspects.

In accordance with the invention, a refractory structure for a kiln car may include one or more of the following features:- (a) a superstructure for carrying removable ware-carrying bats comprising a plurality of columns of refractory material each affording vertically spaced support members for said bats, the lower ends of the columns being located in respective apertures which extend through a refractory base for substantially the whole thickness thereof; (b) a superstructure for carrying removable ware-carrying bats comprising only a plurality of columns of refractory material each afford- ing vertically spaced support members for said bats, with means connecting said columns together only at their upper ends; (c) a superstructure for carrying removable ware-carrying bats comprising a plurality of columns each formed by an upright inner member of refractory material and a plurality of sleeves or collars of refractory material received on said inner member in end-to-end relation; (d) a refractory base of hollow construction filled with lightweight refractory material of low thermal mass and incorporating a plurality of socket members which extend over substantially the entire thickness of the base and afford respective apertures for the reception of the lower end of a corresponding upright. member of refractory material forming part of a superstructure for carrying removable warecarrying bats; (e) socket members which extend over sub- stantially the entire thickness of a refractory base of hollow construction filled with lightweight material of low thermal mass for the reception of upright members forming part of a superstructure, the socket members being secured in the base by means of fixed upright posts which enter into further apertures adjacent to the apertures which receive said upright members; 125 These and other features of the invention will now be described by way of example with reference to the accompanying drawings wherein:Figure 1 shows a refractory superstructure for a kiln car in accordance with the invention, 2 GB2179127A 2 partly in side elevation and partly in longitudi- nal section; Figure 2 shows a corresponding end view; and Figure 3 shows a part-sectional plan view on the line 111-111 of Fig. 1, with the omission of the removable bats and insulation in the interior of the base hereinafter described.

As shown in the accompanying drawing, a preferred embodiment of ware-supporting refractory structure for a kiln car comprises a hollow base 10 which supports a superstructure 30 adapted to carry a plurality of removable ware-carrying bats 50.

The base 10 is of rectangular form and incorporates socket members 11 at the corners, together with further socket members 12 intermediate the corners, and two additional socket members 13 arranged on the longitudinal centre line of the base. The socket members are carried by three longitudinally extending metal straps 14, each having four upright, tubular metal posts 15 secured thereto. The posts 15 enter into respective apertures 16 of corresponding sectional shape which preferably extend through the entire height of the socket members from end-to-end thereof as shown. As shown, the posts 15 and apertures 16 are most conveniently of square shape in cross-section, as are the socket members 11, 12 and-13, although other appropriate shapes could be employed.

The socket members are formed with vertically extending grooves 17 which serve to lo- cate the edges of pairs of refractory panels 18 and 19 which collectively form the lateral walls of the base 10. An outwardly extending baffle 20 is formed by laterally projecting plates which are assembled between the panels 18 and 19 for the purpose of obstruct 105 ing the transmission of radiant energy down wardly from the interior of the kiln around the outside of the base towards a metal trolley (not shown) on which the refractory structure is carried through the kiln.

The interior of the base 10 is filled with insulating blocks 21 covered by a layer of insulating material 22, so that the whole construction is of relatively light weight and low thermal mass.

It is particularly important to note that the socket members 11, 12 and 13 extend over substantially the entire thickness of the base 10. At their upper ends, the socket members support a plurality of cover bats 23 which close the top of the base.

It should also be noted that the posts 15 extend upwardly from the lower end of each socket member over a major part of its height so as to locate the socket members not only against lateral movement, but also effectively to restrain them from rocking about their lower ends.

As can be seen, the apertures 16 are not positioned centrally of the square section socket members, but in the case of the corner socket members 11 the apertures 16 are offset towards one corner of the member, whilst in the case of the side socket members 12, and the central socket members 13, the apertures 16 are offset towards one side. This arrangement enables each socket member to afford a further similar aperture which extends parallel to the aperture 16 through substan- tially the full height of the socket member, and hence throughout substantially the full thickness of the base 10.

Preferably, the corner socket members 11 are formed with open-ended through-apertures 24 arranged in the corners of the socket members diagonally opposed to the corners at which the apertures 16 are formed, whilst the side and central socket members 11 and 12 are formed with open-ended through- apertures 25 which are arranged adjacent to the side of the members opposite to that at which the apertures 16 are formed. The apertures 24 and 25 are conveniently of square shape in section, although other sectional shapes could be employed.

As can be seen from Fig. 3, the socket members 11 and 12 are assembled on the straps 14 in such a way that the throughapertures 24 and 25 are disposed outwardly of the corresponding posts 15 on which the socket members are located. In this way the through apertures 24 and 25 are as close as possible to the outer edges and corners of the base 10 respectively.

Each aperture 24, 25 receives the lower end portion of a column 31 forming part of the superstructure 30. The columns 31 may be of onepiece construction, but in the illustrated embodiment they are of composite construc tion, including a substantially fullheight inner member 32 which is conveniently formed as a length of thick-walled square section ceramic tube of dimensions adapted to fit closely within the apertures 24, 25. In this way, the lower end of each inner member 32 rests on the metal straps 14 and is supported by the corresponding socket member over a length corresponding substantially to the entire thickness of the base 10 so as to provide maxi- mum support.

The inner members 32 in the illustrated embodiment each carry a plurality of alternate sleeves 33 and collars 34. The sleeves each consist of lengths of square section ceramic tube, whilst the collars 34 are of generally plate-like form with a square aperture to receive the inner member 32. As can be seen most clearly in Fig. 1, the collars 34 project laterally relative to the ends of the sleeves 33 so as to afford lugs 39 on which the bats 50 may be supported. Most conveniently, the collars 34 are of generally rectangular shape in plan view, although other shapes could be adopted.

Whilst in the described embodiment the 3 GB2179127A 3 lugs 39 are afforded by collars 34 which are structurally separate from the sleeves 33, it will be appreciated that the sleeves could be formed with integral lugs. Likewise, whilst in the illustrated embodiment the lugs are separate from the inner member 32, it will be appreciated that the columns 31 could have the lugs integrally formed thereon so that the sleeves are not required.

In order to stablise the columns 31 without obstructing the space between them, the columns are connected together above the base 10 only at their upper ends by top bats 38 in such a manner as to hold the columns against relative lateral movement. In the illustrated embodiment each column carries a respective top member which incorporates one or more upstanding projections which enter in corresponding recesses formed at the underside of the top bats 38.

In the embodiment illustrated, the columns 31 at the corners of the superstructure carry top members 35 including a single projection which engages in a corresponding recess at the corner of the top bat supported by the corner column. The columns 31 intermediate the corners carry top members 36 which include a pair of projections arranged to engage in recesses afforded at adjacent corners of the two adjoining top bats supported by such columns. Similarly, the two central columns 31 carry top members 37 which afford four projections to engage in respective recesses at the adjacent corners of the four adjoining top bats supported by those columns.

Whilst the top members could, like the collars 34, be formed with square apertures to locate on the inner member 32 of the column 31, in a preferred arrangement the inner mem- ber 32, whilst extending over substantially the full height of the assembly of sleeves and collars, terminates at its upper end at a position spaced slightly below the upper end of the uppermost sleeve so that the latter affords a shallow socket for the reception of a square- shaped projection at the underside of the cor responding top member. Alternatively, the top member could be formed with a smaller downward projection adapted to enter the end of the inner member 32, which is most con- 115 veniently of tubular form, although it could be made from solid rod if required.

It will be appreciated that the removable bats 50 can be placed in position on the lugs 39 afforded by the collars 34 from either side of the superstructure since there is not obstructioq to prevent such a bat being passed from one side of the superstructure to the other. Each removable bat 50 will be sup- ported adjacent to its corner by four lugs carried by respective columns 31. However, if it is desired to provide three-point support for the bats, it would be possible to modify the base 10 so that the central strap 14 provides support for only three columns, at positions aligned centrally between the pairs of columns supported by the outermost straps 14. In this way, each removable bat 50 would be supported by three lugs, although in this case the bats could not be passed through the superstructure from one side to the other.

It is particularly to be noted that, contrary to previous practice, the lower ends of the columns 31 do not require to be embedded in massive supports. By contrast, the socket members which give the required support are comparatively light in weight, and this is made possible by the fact that they are formed with two apertures, one for locating the socket member in a fixed position on the corresponding strap 14, and one for receiving the lower end of the column 3 1. Since these two apertures extend parallel to one another, the members receives therein can extend through sub- stantially the full height of the socket member and thereby maximise the support which is provided within the vertical dimensions of the base.

Forming the columns 31 by assembling sleeves 33 and collars 34 on the inner member 32 has the advantage that the sleeves can readily be formed to various lengths so as to enable the superstructure 30 to be adapted to support removable bats 50 at varying spac- ings according to the requirements of the ware being fired.

As will be apparent the superstructure 30 is itself of relatively lightweight construction so as to minimise energy loss due to thermal cycling and yet the structure is stable enough to enable the removable bats 50 to be loaded mechanically.

The features disclosed in the foregoing description, or the accompanying drawings, ex- pressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, or a class or group of substances or compositions, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims

1. A refractory structure of a kiln car corn prising a refractory base for mounting on a trolley and a refractory superstructure for carrying removable ware-carrying bats wherein said superstructure comprises a plurality of columns of refractory material, each affording vertically spaced support means for receiving said bats, the lower ends of the columns being located in respective apertures which extend through said refractory base for substan- tially the entire thickness thereof.

2. A refractory structure according to Claim 1 wherein the base incorporates a plurality of socket members of refractory material which extend over substantially the entire thickness of the base and afford respective 4 GB2179127A 4 apertures for the reception of lower end portions of said columns.

3. A refractory structure according to Claim 2 wherein said socket members are secured in the base by means of fixed upright posts received in further apertures formed in the socket members.

4. A refractory structure according to Claim 3 wherein said apertures for the recep- tion of the lower end portions of the columns and said apertures which receive the posts extend alongside one another in each socket member and throughout substantially the entire height of the socket member.

5. A refractory structure according to Claim 4 wherein such socket members are provided at the corners of the structure and in said corner socket members the apertures for the reception of the lower end portions of the columns are disposed diagonally outwardly offset from the apertures in which the posts are received.

6. A refractory structure according to Claim 4 or Claim 5 wherein such socket mem- bers are provided at intermediate positions along the sides of the structure and in said side socket members the apertures for the reception of the lower bed portions of the columns are disposed outwardly offset from the apertures in which the posts are received.

7. A refractory structure according to Claims 4 to 6 wherein the posts are carried by metal strips at the underside of the base and the lower ends of the columns rest on said strips.

8. A refractory structure according to any one of Claims 1 to 7 wherein the base is of hollow construction comprising side plates and cover plates and is filled with lightweight re- fractory material of low thermal mass.

9. A refractory structure according to any one of Claims 1 to 8 wherein said columns are each formed by an upright inner member of refractory material and a plurality of super- posed outer members of refractory material received on said inner member in end-to-end relation and affording said support means for the bats.

10. A refractory structure according to Claim 9 wherein said outer members comprise alternate spacer members and support members which afford said support means for said bats.

11. A refractory structure according to any one of Claims 1 to 10 wherein said columns are connected together above the base only at their upper ends.

12. A refractory structure according to Claim 11 wherein said columns are connected together by means of top plates.

13. A refractory structure according to Claim 12 wherein each of said top plates incorporates recesses at the corners thereof and each of the columns carries at its upper end a respective top member respectively affording projections adopted to enter into the recesses at the corners of the top plates.

14. A refractory structure for a kiln car substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

Printed for Her Majesty's Stationery Office by Burgess & Son (Abingdon) Ltd, Dd 8817356, 1987. Published at The Patent Office, 25 Southampton Buildings, London, WC2A 'I AY, from which copies may be obtained.