GB1591331A

GB1591331A - Constructional blocks

Info

Publication number: GB1591331A
Application number: GB1404377A
Authority: GB
Original assignee: WFJ REFRACTORIES Ltd
Current assignee: WFJ REFRACTORIES Ltd
Priority date: 1978-05-26
Filing date: 1978-05-26
Publication date: 1981-06-17

Description

(54) CONS TRUCTIONAL BLOCKS (71) We, W.F.J. REFRACTORIES LIMI TED, formerly, W.F.J. Construction Co.

(North Wales) Limited, British Company of Colomendy Industrial Estate, Rhyl Road, Denbigh, Clwyd LL16 5TA, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to constructional blocks for forming walls of tubed boilers, and is particularly applicable to forming walls between offset rows of tubes.

According to one aspect of the invention there is provided a wall structure between offset rows of boiler tubes and comprising in at least one course of the wall a plurality of refractory blocks each having a central transverse recess in a face thereof, tubes of one of the rows being accommodated at least partly in said recesses and tubes of the other row being accommodated at least partly in recesses defined between adjacent corner portions of the opposite faces of the blocks in that course.

Preferably at least one of the corner portions of each block is radiussed about an axis of rotation for the block about a tube accommodated in the first-mentioned recess, the radius of the corner being such that the recess in said face of the block can be engaged with a boiler tube and the block rotated into position between the rows of tubes.

Successive courses of the wall may be interlocked by alternate bonding, in usual bricklaying fashion, and/or by interengagement of juxtaposed surfaces of adjacent rows of blocks, say by engaging opposed shoulders of said juxtaposed surfaces. Where the blocks have their opposite end faces stepped to provide oppositely facing shoulders the desired interlocking is obtained by vertically transposing blocks in successive rows.

According to a second aspect of the invention there is provided a constructional block for use in constructing a wall structure of the first aspect and having in a face thereof a central transverse recess to at least partly accommodate a boiler tube and at least one corner of the opposite face radiussed or otherwise truncated.

Conveniently both corners of the block are similarly shaped, preferably the or each corner being radiussed about an axis of rotation of the block about a tube accommodated in the recess. The radius of the or each corner may then be optimised to allow a block of a length substantially equal to the pitch of the tubes to be rotated, using the accommodated tube as a pivot, into the desired position between the two rows of tubes.

End faces of the block may be stepped to provide a shoulder conveniently extending in a plane generally parallel with the rows of tubes and preferably both end faces are oppositely stepped to provide oppositely facing shoulders.

An embodiment of the invention will now be described by way of example only and with reference to the drawings accompanying the Provisional specification in which: Figure 1 is a perspective view of a constructional block, Figure 2 is a front elevational view of a portion of a wall assembled from the blocks of Figure 1.

Figure 3 is a plan view of one course of the wall.

Figure 4 is a similar view to Figure 3 but of the next course of the wall.

A constructional block 10 in Figure 1 is a pre-cast or prefired block of refractory material.

The block is generally rectangular in shape and in one longitudinal face 11 has a central transverse semi-cylindrical recess 12. The diameter of the recess corresponds to that of a boiler tube to which the block is to be fitted as part of a wall.

The opposite face 13 of the block has radiussed corners 14. The radiussing of the corners 14 is about the same centre as that of the semi-cylindrical recess 12.

The upper surface 15 of the block 10 is stepped to provide a central shoulder 16 parallel to the recessed face 11. The lower surface 17 of the block is oppositely stepped to provide a similar depth but oppositely facing shoulder 18. The shoulders serve for vertical interlocking of stacked blocks.

A wall 20 comprises a number of courses of the blocks laid end-to-end between two offset rows of boiler tubes 21, using alternate bonding in normal bricklaying fashion. The length I of each block is equal to the pitch of the boiler tubes in each row and the blocks in successive rows are transposed so that the recesses of blocks in successive rows engage a different one of the rows of tubes. The tubes of the other row then locate in recesses 22 formed on the opposite side of the wall between the radiussed corners of the blocks.

Adjacent courses of the wall comprise similar blocks but vertically transposed so that the shoulders of the blocks in each course of the wall bear against the corresponding shoulders of the next course and provide vertical interlocking of the wall. Displaceinent of the blocks of consecutive rows by half of the block length provides the aforementioned alternate bonding so that the wall is securely interlocked horizontally and vertically.

The ends of the wall are keyed into adjacent walls or other structures by special key blocks 24, of similar shape to the basic block but with a key piece protruding from the end thereof. An additional special block 25 is used to complete the alternate bonding. This latter block 25 is a half block having both sides radiussed.

When the wall is being built up each block is positioned slightly above the preceding course with its recess engaging the outer side of the tube as shown at 26 in Figure 4 and is then rotated in the direction of the arrow R into the space between the offset rows of tubes until the end of the block abuts the end of the previous block in that course. The block is then lowered onto the underneath course of blocks so that the shoulder of one block bears against the corresponding shoulders of the two lower blocks it straddles.

Radius sing of the corners remote from the recessed face facilitates rotation of the blocks during fitting as described.

An advantage of such fitting is that the blocks can be fitted between the tubes at positions intermediate their length so it is not necessary to slide each block along the length of the tube, nor is it necessary to allow clearance for fitting of the block over the end of the tube.

It will be appreciated that only one opposite corner of the block need be radiussed to allow for such rotational fitting. The other corner might be otherwsie truncated, say with a concave recess of similar diameter to a boiler tube or even flat. However, an advantage of both corners being radiussed is that the block may be rotated into position from either direction.

WHAT WE CLAIM IS: 1. A wall structure between offset rows of boiler tubes and comprising in at least one course of the wall a plurality of refractory blocks each having a central transverse recess in a face thereof, tubes of one of the rows being accommodated at least partly in said recesses and tubes of the other row being accommodated at least partly in recesses defined between adjacent corner portions of the opposite faces of the blocks in that course.

2. A wall structure as claimed in claim 1, wherein each block is of a length substantially equal to the pitch of the tubes in each row and at least one of the corner portions of each block is radiussed about an axis of rotation for the block about a tube accommodated in the first-mentioned recess, the radius of the corner being such that the recess in said face of the block can be engaged with a boiler tube and the block rotated into position between the rows of tubes.

3. A wall structure as claimed in claim 1 or 2, wherein juxtaposed surfaces of blocks in adjacent courses interengage for vertical interlocking of the courses.

4. A wall structure as claimed in claim 3, wherein adjacent courses are interlocked by engagement of respective opposed shoulders of said juxtaposed surfaces.

5. A wall structure as claimed in any preceding claim, comprising a plurality of alternately bonded courses of blocks.

6. A wall structure as claimed in any preceding claim, wherein blocks in successive rows are transposed such that said first recesses of blocks in successive rows engage different rows of tubes.

7. A wall structure as claimed in claim 6 as appendant to claim 4, wherein each block has opposite end faces stepped to provide oppositely facing shoulders.

8. A wall structure between offset rows of boiler tubes and substantially as described herein with reference to the drawings accompanying the Provisional specification.

9. A refractory block for use in constructing a wall structure as claimed in claim 1 having a central transverse recess in one face thereof to at least partly accommodate a boiler tube and at least one corner of the opposite face radiussed or otherwise truncated.

10. A block as claimed in claim 9, wherein both corners of the opposite face are radiussed or otherwise truncated, 11. A block as claimed in claim 9 or 10, wherein the or each corner is radiussed about an axis of rotation for the block about a tube accommodated in the recess.

12. A block as claimed in claim 11, wherein the recessed face of the block is substantially equal in length to the pitch of the tubes in each row and the radius of the or each corner is such that the block can be

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. facing shoulder 18. The shoulders serve for vertical interlocking of stacked blocks. A wall 20 comprises a number of courses of the blocks laid end-to-end between two offset rows of boiler tubes 21, using alternate bonding in normal bricklaying fashion. The length I of each block is equal to the pitch of the boiler tubes in each row and the blocks in successive rows are transposed so that the recesses of blocks in successive rows engage a different one of the rows of tubes. The tubes of the other row then locate in recesses 22 formed on the opposite side of the wall between the radiussed corners of the blocks. Adjacent courses of the wall comprise similar blocks but vertically transposed so that the shoulders of the blocks in each course of the wall bear against the corresponding shoulders of the next course and provide vertical interlocking of the wall. Displaceinent of the blocks of consecutive rows by half of the block length provides the aforementioned alternate bonding so that the wall is securely interlocked horizontally and vertically. The ends of the wall are keyed into adjacent walls or other structures by special key blocks 24, of similar shape to the basic block but with a key piece protruding from the end thereof. An additional special block 25 is used to complete the alternate bonding. This latter block 25 is a half block having both sides radiussed. When the wall is being built up each block is positioned slightly above the preceding course with its recess engaging the outer side of the tube as shown at 26 in Figure 4 and is then rotated in the direction of the arrow R into the space between the offset rows of tubes until the end of the block abuts the end of the previous block in that course. The block is then lowered onto the underneath course of blocks so that the shoulder of one block bears against the corresponding shoulders of the two lower blocks it straddles. Radius sing of the corners remote from the recessed face facilitates rotation of the blocks during fitting as described. An advantage of such fitting is that the blocks can be fitted between the tubes at positions intermediate their length so it is not necessary to slide each block along the length of the tube, nor is it necessary to allow clearance for fitting of the block over the end of the tube. It will be appreciated that only one opposite corner of the block need be radiussed to allow for such rotational fitting. The other corner might be otherwsie truncated, say with a concave recess of similar diameter to a boiler tube or even flat. However, an advantage of both corners being radiussed is that the block may be rotated into position from either direction. WHAT WE CLAIM IS:

1. A wall structure between offset rows of boiler tubes and comprising in at least one course of the wall a plurality of refractory blocks each having a central transverse recess in a face thereof, tubes of one of the rows being accommodated at least partly in said recesses and tubes of the other row being accommodated at least partly in recesses defined between adjacent corner portions of the opposite faces of the blocks in that course.

10. A block as claimed in claim 9, wherein both corners of the opposite face are radiussed or otherwise truncated,

11. A block as claimed in claim 9 or 10, wherein the or each corner is radiussed about an axis of rotation for the block about a tube accommodated in the recess.

rotated about a tube of one row accommodated in the recess into the desired position between the rows.

13. A block as claimed in any of claims 9 to 12, wherein the recess has a semi-cylindrical section.

14. A block as claimed in any of claims 9 to 13, wherein an end face of the block is stepped to form a shoulder.

15. A block as claimed in claim 14, wherein the opposite end face of the block is stepped to form an oppositely facing shoulder.

16. A block for use in constructing walls between offset rows of boiler tubes substantially as herein described with reference to and as shown in the drawings accompanying the Provisional specification.

17. A tubed boiler having between offset rows of tubes a wall structure as claimed in any of claims 1 to 8.