Refractory impact pad

Abstract

The invention relates to a refractory (fireproof) impact pad (also called impact pot).

Claims

1. Refractory impact pad providing the following features in its use position: a) a bottom (10) with an upper impact surface (10s), b) a wall (12) with an inner surface (12i), c) the wall (12) extending from said bottom (10) upwardly to an upper end (14) of the impact pad, d) the inner surface of the wall (12) and the upper impact surface (10s) of the bottom (10) define a space (16), e) a plurality of barriers (20) project from the inner surface (12i) of the wall (12) into said space (16), f) said barriers (20) are shaped as an inverted V or inverted W with a corresponding number of legs (201), and g) said barriers (20) are arranged with a distance to each other at least in a horizontal direction.

2. Impact pad according to claim 1, wherein the said barriers (20) are arranged at different distances to the upper impact surface or at different distances to the upper end (14) of the impact pad or both.

3. Impact pad according to claim 1, wherein some or all of the said barriers (20) which are arranged at a distance to each other in a vertical direction are overlapping each other in a horizontal direction.

4. Impact pad according to claim 1, wherein some or all of the said barriers (20) are designed with at least one cross-sectional profile of the group comprising: rectangular cross-section, triangular, semi-circular cross-section, oval cross-section or combinations thereof.

5. Impact pad according to claim 1, wherein some or all of the said barriers (20) are designed as an inverted V or inverted W with an angle of between >45° and <170° between two adjacent legs (201).

6. Impact pad according to claim 1, wherein some or all of the said barriers (20) are designed with legs (201) or different lengths.

7. Impact pad according to claim 1, wherein some or all of the said barriers (20) project from the inner surface (12i) of the wall by at least 10 mm.

8. Impact pad according to claim 1, wherein some or all of the said barriers (20) project from the inner surface (12i) of the wall by 50 mm at most.

9. Impact pad according to claim 1, wherein the shortest distance between adjacent barriers (20) is at least 5 mm.

10. Impact pad according to claim 1, wherein the shortest distance of adjacent barriers (20) is 40 mm at most.

11. Impact pad according to claim 1, wherein the barriers (20) are an integral part of the impact pad.

12. Impact pad according to claim 1, wherein the wall (12), at its upper end (14), has no protrusion towards the space (16).

13. Impact pad according to claim 1, wherein the legs (201) of at least one barrier (20) of an inverted V or inverted W have a curved transition area (20t) between the legs (201).

14. Impact pad according to claim 1 with at least one further barrier shaped as a V or W and arranged between said barriers (20) shaped as an inverted V or inverted W.

15. Impact pad according to claim 1, wherein the barriers (20) extend over at least 80% of the circumferential length of the inner surface (12i) of the wall (12).

Description

(1) The Figures show, each in a schematic representation:

(2) FIG. 1: A longitudinal section of an impact pad according to the invention.

(3) FIG. 2: A top view on the impact pad according to FIG. 1.

(4) FIGS. 3.1-3.5: Possible shapes of an inverted V- or W-barrier.

(5) The impact pad comprises a bottom 10 with an upper impact surface 10s. Bottom 10 (and correspondingly impact surface 10s) is of rectangular shape. Insofar wall 12 of said impact pad is made of four wall sections 12a, b, c, d, integral with each other and extending from said bottom upwardly to a circumferential (squared) upper end 14 of the impact pad.

(6) The inner surface 12i of said wall 12 and the upper impact surface 10s of bottom 10 define a central space 16 of the impact pad as well as a squared inlet/outlet opening 18 for a melt at the upper end 14.

(7) The impact pad is characterized by a plurality of barriers 20.

(8) According to FIG. 1 wall section 12d is equipped with three barriers 20a, b, c arranged at a distance to each other, wherein two barriers 20a, c are arranged above the third barrier 20b, which third barrier 20b being placed such that it overlaps corresponding legs 201 of the other two barriers 20a, c.

(9) FIG. 1 further shows barriers 20 at adjacent wall sections 12b, 12a, partly in a longitudinal sectional view. All barriers 20 have the same shape and size. According to FIG. 1 they are designed as an inverted V. In other words: They have a “roof-like shape” in a side view providing an angle α of 135° between its respective legs 201.

(10) In the present embodiment the minimum distance between adjacent barriers 20, 20a, b, c between a barrier 20 and the impact surface 20s, between each barrier 20, 20a, b, c and the upper circumferential end 14 is about 20 mm.

(11) Arrow A symbolizes the flow of a metal stream when entering the impact pad in the proximity of a corresponding wall section 12a . . . 12d. The inverted V-shape of the barriers 20 causes the metal stream to split up into partial streams which then follow the shape of the corresponding barrier 20 in opposite directions. These partial streams may hit further barriers arranged below the said first barrier (as indicated in FIG. 1) and may be split up again in a similar way as described above.

(12) Any metal stream flowing upwardly within the impact pad (its space 16) in the proximity of a wall section 12a . . . 12d will hit the lower contact surface of the corresponding barrier 20 and follow the corresponding sloped contact area at least up to the transition area 20t of the respective barrier 20 before turning inwardly (into space 16) and then upwardly to leave the set impact pad via opening 18.

(13) FIGS. 3.1 and 3.2 each represent a barrier of a standard inverted V-shape, FIG. 3.2 with one shortened leg.

(14) FIG. 3.3 shows and inverted W-barrier with curved inner and outer transition areas between the W-legs.

(15) The barrier of FIG. 3.4 has an angled outer transition area, a curved inner transition area and legs of different width.

(16) FIG. 3.5 represents a barrier similar to FIG. 3.2 but with slightly curved legs, while the general shape of an inverted V is maintained.

(17) It has been proved by computer simulation and water modeling experiments that this impact pad allows reductions in the velocity of the metal stream, reduces turbulences within the impact pad, reduces the surface velocity and the surface turbulences within the corresponding metallurgical vessel, compared with all types of prior art devices as mentioned above. It further minimizes the risk of splashing in case of a misaligned shroud.

(18) This is an indication for a more efficient energy dissipation inside the impact pad.