REFRACTORY ANCHOR FOR A FURNACE REFRACTORY TILE

Abstract

A refractory anchor for a refractory tile for a furnace and to a method to manufacture such a refractory anchor, wherein the refractory anchor has an overall truncated cone shape, wherein the refractory anchor is divided in at least two parts with one or more dividing planes between the parts which run from bottom plane to top plane of the truncated cone shaped refractory anchor.

Claims

1. A refractory anchor for a refractory tile for a furnace, wherein the refractory anchor has an overall truncated cone shape, wherein the refractory anchor is divided in three or more parts and wherein radial dividing planes run from bottom plane to top plane of the truncated cone shaped refractory anchor.

2. The refractory anchor according to claim 1, wherein the parts of the refractory anchor are identically shaped.

3. The refractory anchor according to claim 1, wherein the refractory anchor has a first cone part and a second cone part each with a truncated cone shape, with a shoulder part as transition between the first and second cone parts.

4. The refractory anchor according to claim 3, wherein the bottom plane of the second cone part is at a hot side when in use and wherein the diameter of the bottom plane of the first cone part is less than the diameter of the top plane of the second cone part.

5. The refractory anchor according to claim 1, wherein height of the first cone part is larger than height of the second cone part.

6. The refractory anchor according to claim 5, wherein the height of the second cone part is less than 65% of the height of the first cone part.

7. The refractory anchor according to claim 5, wherein the height of the second cone part is between 35% and 50% of the height of the first cone part.

8. The refractory anchor according to claim 1, wherein the shoulder part is concavely curved with a radius of curvature in the range of 5-30 mm.

9. The refractory anchor according to claim 1, wherein the shoulder part is concavely curved with a radius of curvature in the range of 15-25 mm.

10. The refractory anchor according to claim 1, wherein an opening angle of the first cone part and/or second cone part are in the range of 2-15.

11. A method for the manufacturing of a refractory anchor for a refractory tile for a furnace, wherein the refractory anchor has an overall truncated cone shape and wherein the refractory anchor is divided in at least three parts, comprising the steps of: providing a mould for the refractory anchor divided in parts, filling the mould with a refractory moulding compound, firing the refractory anchor, and applying a mortar between the parts of the refractory anchor.

12. The method according to claim 11, wherein the mortar is an air curing mortar.

13. The method according to claim 11, wherein a complementary shape to receive an anchor bolt is formed in the refractory anchor.

14. A mould for the manufacturing of a refractory anchor for a refractory tile for a furnace, wherein the refractory anchor has an overall truncated cone shape and wherein the refractory anchor is divided in at least two parts, wherein the mould has an overall truncated cone shape which is open at one side and closed at the opposite side, a protrusion in the closed side which is shaped for the refractory anchor to receive an anchor bolt and one or more dividing plates which run from the closed side to the open side of the mould.

15. The mould according to claim 14, wherein the dividing plates have a thickness in the range of 1-5 mm.

16. The method of claim 11, wherein the refractory anchor has an overall truncated cone shape, wherein the refractory anchor is divided in three or more parts and wherein radial dividing planes run from bottom plane to top plane of the truncated cone shaped refractory anchor.

17. The method of claim 11, wherein the parts of the refractory anchor are identically shaped.

18. The method of claim 11, wherein the refractory anchor has a first cone part and a second cone part each with a truncated cone shape, with a shoulder part as transition between the first and second cone parts.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The invention will be further explained on hand of the example shown in the drawing, in which:

[0034] FIG. 1A,B show a side view of respectively a refractory anchor divided in three parts and a view of an undivided refractory anchor,

[0035] FIG. 2A-C show top view, side view and bottom view of a refractory anchor divided in four parts, and

[0036] FIG. 3 shows a graph with the stresses a three different locations for a single part refractory anchor up to a 4 part refractory anchor.

DETAILED DESCRIPTION OF THE DRAWINGS

[0037] In FIG. 1A a refractory anchor 1 is shown that is divided in three parts, with only the parts 2, 3 visible, wherein the darker shading is indicative of the maximum stresses occurring in the anchor when cooling down. The stresses with a three-part anchor occur at the joining faces 6,7 of the three-part anchor 1 at or near the shoulder 8 between the first cone part 9 and the second cone part 10.

[0038] The side view of an undivided refractory anchor 1 of FIG. 1B clearly shows that the stresses diminish in downward and upward direction from the shoulder 6.

[0039] These stresses with a three-part anchor only occur around the division because of the stress relieving effect of the joints. With an anchor in one piece these stresses occur over the entire anchor.

[0040] FIG. 2A shows a top view of a refractory anchor 1 which is divided in four parts 2, 3, 4, 5 wherein the stresses as occur in the three-part anchor are far less and also less than in an anchor made in one piece. The respective side view of FIG. 2B and the bottom view of FIG. 2C show the in this case symmetrical division of the refractory anchor in four parts.

[0041] In FIG. 3 a diagram is shown with the stresses occurring with the cooling down of and anchor divided in two, three and four parts. The stresses are given as occurring at or near the shoulder, the side and the bottom, wherein the side is the cone envelope of the second cone part 10 and the bottom is the part of the second cone part 10 that faces the interior of the re-heat furnace and which is subjected to the highest temperature differences over time.

[0042] Directly apparent from the diagram is that the two-part anchor is the least favourable embodiment with the largest stresses occurring at the shoulder and the side face of the anchor. Only with regard to the bottom part the one-piece form is worse. This is related to the fact that in the two-part anchor an increased, but localized around the division plane, bending moment occurs which increases the stress intensity. This increased bending moment is less pronounced for the three and four-part anchors.

[0043] The three part form is clearly favourable over the one-piece and two-part form anchor with the largest decrease of the occurring stresses being at or near the shoulder part and a significant decrease of the stresses occurring at the bottom of the anchor. The stresses at the side are less significant reduced with respect to the one piece form, but still there is a decrease.

[0044] The four part anchor shows even further decreased stresses and here the decrease of the stresses occurring at the side and the bottom are significantly reduced in comparison with the stresses occurring at the side and bottom of a three part anchor.