This invention relates to a sinter cooler of a sintering plant for use in metallurgy, comprising a cooling-air chamber and a sinter cooling chamber including a perforated plate, which can travel over the same, and comprising a cooling gas seal between the upper surface of the cooling-air chamber and the lower surface of the sinter cooling chamber.
In such sinter coolers, external seals of a cotton laminate (e.g. Laminex®), which are provided on the upper surface of rigid rubber strips, previously have been used to avoid cooling air losses. The rubber strips are arranged on adjustable angular brackets, which in turn are fixed on vertical stationary sealing plates. These seals wear relatively quickly and frequently must be readjusted by hand.
It is the object of the present invention to equip a sinter cooler as mentioned above with a novel cooling gas seal, which with an improved durability safely reduces cooling air losses and hence the amount of required cooling air, without increasing the frictional resistance. This should lead to a saving of operating costs and improve the effectiveness of the cooler.
In a sinter cooler as mentioned above, this object is solved in particular in that the cooling gas seal carried along with the sinter cooling chamber includes sealing elements of an elastomeric material, which are arranged with a vertical play such that they are seated on the lateral upper edges of the stationary vertical cooling-air chamber wall, which extend in direction of travel of the sinter cooling chamber, and during travel of the sinter cooling chamber slide along the upper edges, wherein the sealing elements are mounted in a vertically movable manner by means of a weight-loaded holder and a guide pin. The sealing elements preferably are replaceable.
Such seal is self-compensating, because in the case of the end-face wear of the sealing elements the same maintain their sealing function with respect to the cooling-air chamber wall by automatic readjustment. In this way, the service life of the cooling gas seal is prolonged considerably. Due to the reliable sealing, operating costs are saved and the effectiveness of the cooler is improved. The drive unit for the traveling sinter cooling chamber need not be dimensioned larger than before.
Preferably, the sealing elements are arranged outside a protective side wall of the sinter cooling chamber and at the lower end thereof, whereby the sealing elements are shielded against sinter dust and heat.
Furthermore, the sealing elements preferably are provided in a region inside an e.g. circular rail base of the cooling-air chamber, in order to protect the bearing of the bogie wheels of the sinter cooling chamber against sinter dust.
To realize the self-adjusting sealing function, the sealing elements are mounted in a vertically movable manner by means of a possibly weight-loaded holder disposed e.g. as a kind of framework and by means of a guide pin. The weight load can ensure a sufficient contact pressure of the sealing elements on the upper edge of the stationary cooling-air chamber wall, without adversely affecting the slidability.
For an easily replaceable assembly of the sealing elements, the guide pins can be received in possibly angular brackets which in turn are attached to connecting plates, in particular welded to the same, wherein the connecting plates preferably are releasably connected with stiffening ribs below the sinter cooling chamber wall.
The respective sealing element holder overlaps the associated sealing element preferably in a roof-like manner with corresponding inclined surfaces, so that fine sinter dust easily can slip off downwards.
In accordance with a development of the invention, the flat smooth upper edge of the cooling-air chamber wall, which possibly is formed by a stationary sealing plate of the cooling-air chamber wall, is formed with such a width that even in the case of a lateral displacement of the sinter cooling chamber, which for example moves on rails by means of bogie wheels, the sealing elements will always fully rest on the upper edge of the cooling-air chamber wall with their lower end face.
For example, a plurality of sealing element portions can adhesively be bonded at their ends to form an integral sealing element.
The ends of the sealing element segments facing each other preferably overlap each other and form a miter.
In their lower region, the sealing elements preferably are made of a wear-resistant, creep-resistant polymer having good sliding properties, whereas in their upper region they are made of a polymer that bonds well to metal. The two polymer components should also bond well to each other, e.g. by adhesion or by co-extrusion. It is, however, less expensive to use only one single material for the sealing elements.
In accordance with a preferred aspect of this invention, the sealing elements in particular are made of an ultra-high molecular weight polyethylene (PE-UHMW).
Preferably, the upper edge of the cooling-air chamber wall is formed by a stationary sealing strip with round, preferably circular cross-section, in order to avoid a deposition of sinter dust and offer a small contact surface for the sealing elements.
Further developments, advantages and possible applications of the invention can be taken from the following description of an embodiment and the drawing. All features described and/or illustrated form the subject-matter of the invention per se or in any combination, also independent of their inclusion in individual claims and/or their back-reference.
In the drawing:
The embodiment of a sinter cooler including the invention as shown in the Figures is part of a sintering plant for use in metallurgy. It serves to cool the lumpy sintered ore to be supplied to a blast furnace by means of cooling air and to supply the thermal energy of the hot waste air recovered for example to another load.
The sinter cooler has a cooling-air chamber 1 and a sinter cooling chamber 3 for the hot sinter material accommodated therein, which for example by means of bogie wheels 22 can travel on a rail track 17, 19 and includes a perforated plate 2 for the supply of cooling air. To minimize a loss of cooling air, a cooling gas seal 4 is provided between the upper edge 5 of the cooling-air chamber 1 and the lower surface of the sinter cooling chamber 3. The upper portion of the cooling-air chamber wall 7 is formed by stationary, in particular metallic sealing plates 18.
The cooling gas seal 4 carried along with the sinter cooling chamber 3 includes replaceable sealing elements 6 of an elastomeric material. The sealing elements 6 are mounted with a vertical play such that they are seated on the smooth upper edge 5 of the sealing plates 18 of the stationary vertical cooling-air chamber wall 7 and during travel of the sinter cooling chamber 3 slide along the upper edge 5.
The sealing elements 6 are arranged outside a protective side wall 8 of the sinter cooling chamber 3 and at the lower end thereof such that the former are protected against sinter dust and heat. The sealing elements 6 are mounted in a vertically movable manner by means of a possibly weight-loaded holder 9 and a guide pin 10, so that they can compensate a possible wear by automatic readjustment. The upper head 21 of the guide pin 10 forms a stop when the sealing elements 6 have reached their maximum of admissible wear. In the illustrated embodiment, the guide pins 10 are accommodated in angular brackets 11 in a vertically movable manner, wherein the through holes through which the guide pins 10 are passed are large enough to provide for freely shifting the sealing elements 6 with respect to the sealing plates 18.
The brackets 11 are attached to connecting plates 12 for example by welding. For a fast replacement of used sealing elements 6, the connecting plates 12 in turn are releasably connected with stiffening ribs 13 below the sinter cooling chamber wall 14. The holders 9 overlap the associated sealing element 6 in a roof-like manner with corresponding inclined surfaces 15, so that sinter dust obtained is easily discharged downwards upon reaching the discharge area. The holders 9 also can be formed in two parts and be clamped onto the sealing elements 6 from the side, in order to provide for an easy assembly and disassembly.
The end faces 16 of the sealing elements 6 are formed with such a width that they will always rest on the upper edge 5 of the cooling-air chamber wall 7, even in the case of a lateral displacement of the traveling sinter cooling chamber 3 by e.g. ± 25 mm. Preferably, the end faces 16 have a width of about 6 to 12 cm.
A plurality of sealing element portions can be connected with each other at their ends to form an integral sealing element 6. The connection can be made for example by bonding. To improve tightness, the ends of the sealing element segments facing each other furthermore overlap to form a miter.
For further improvement of a permanent operability of the cooling gas seal 4, the sealing elements 6 are formed in their lower region of a wear-resistant, creep-resistant polymer having good sliding properties and in their upper region of a polymer that bonds well to metal. Furthermore, the polymers expediently should be selected such that they can easily be connected with each other, for example by bonding or by co-extrusion.
The upper edge 5 of the cooling-air chamber wall 7 in particular can be formed by a sealing strip 23 which is round, in particular circular in cross-section (see
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