Patent Grant
9920995
The invention relates to a method and system of dispensing a predetermined amount of sand from a compact sand reservoir, via a nozzle, as a directed stream of sand into a tap hole of a metal making furnace, such as for example, a steel making furnace.
In metal making furnaces of the prior art, sand is filled into the furnace, and particularly into a tap hole before the furnace is filled with a charge of metal, for example, sorted scrap or other metal feedstock. For example, in steel making furnaces, a tap hole is often filled with sand in incremental amounts after an operator inspects the tap hole to determine whether additional sand is required to properly fill the tap hole. The operator may use a camera or other device to visually inspect the tap hole at several different times during the sand filling cycle. Often, there will be delays as the operator waits for a clear view of the tap hole, as dust settles after an incremental fill, to see whether additional sand must be dispensed to properly fill the tap hole.
In prior art sand filling systems, the sand is often dispensed directly from a bulk storage sand reservoir often located near the furnace, for example, on a structurally reinforced roof above the furnace, or on an interior floor space of the metal making plant. In those instances where the sand must be supplied as unguided charges of sand in discrete incremental steps, and particularly in those instances where the volume of sand must be adjusted to compensate for sand dispensed into the furnace, but not into the tap hole, production time will be lost dispensing additional increments of sand to properly fill the tap hole.
In some prior art systems, such as the system of US patent publication number US 2013/0320601 published on Dec. 5, 2013 by Nucor Corp., additional production time may be lost by operating a plunger to clear metal flash and other formations which may plug or obstruct an access port, for example, a chimney hole used as an unrestricted opening to fill sand into a tap hole in a steel making furnace. The chimney hole may be cleared by a remotely controlled plunger as disclosed in the Nucor application, or in some instances, the obstructions may be cleared manually by an operator who could be exposed to risk of injury while working in close proximity to the high temperature furnace. Any obstructions are removed and sand is incrementally charged into that tap hole after the operator performs visual inspections following each sand filling step, of which there would be several incomplete filling steps, until the sand filling is properly completed. Each incremental charging step adds to the production time for the metal making process. Similar issues may arise in those systems where an operator will interrupt the sand filling cycle to manually clear obstructions from chimney holes or similar openings used to supply sand into a metal making furnace. Therefore, it would be desirable to reduce the frequency and duration of any clearing steps and to reduce the risk to operators who might otherwise be required to approach an operating furnace to clear obstructions that might interfere with sanding of the furnace or inspecting the tap hole.
Often, an unnecessarily significant amount of sand may be lost as some of the sand is dispensed, unguided, into the furnace to accumulate adjacent but outside of the tap hole. The total additional volume of used sand which is dispensed and accumulated outside of the tap hole may represent a significant expense for each production cycle, and an even greater expense over a lengthy production period. In many instances it will be desirable to reduce the consumption of sand during operation of metal making furnaces.
It would also be desirable to reduce the operating time for a metal making furnace, where possible, by reducing the amount of time needed to dispense sand into the tap hole of a metal making furnace. In some instances, it may be desirable to more accurately direct a stream of a predetermined amount of sand into the tap hole.
The present invention may be applied to sanding systems and methods of sanding metal making furnaces, for example, steel making furnaces, to ameliorate one or more of these disadvantages or one or more of the other disadvantages associated with prior art sanding systems and methods which are known by persons skilled in the prior art.
The following presents a simplified summary of the invention in order to provide a basic understanding to the reader. This summary is not an extensive overview of the disclosure and it does not necessarily identify key/critical elements of the invention or delineate the scope of the invention. Its sole purpose is to present some concepts disclosed herein in a simplified form as a prelude to the more detailed description that is presented later.
In one aspect, the present invention is directed to a sand dispensing system for use in a steel making furnace. Although the following summary, and the description, will in part describe the application of the invention to steel making furnaces, skilled persons will appreciate that this invention may be readily adapted for use with other metal making furnaces. Similarly, other aspects of the invention include methods of sanding internal features, such as for example tap holes, for use in association with high temperature metal making furnaces, including steel making furnaces.
In one aspect, the sand dispensing system comprises a movable, and preferably compact, sand storage reservoir for dispensing a predetermined amount of sand into a tap hole of a steel making furnace. In this example, the sand storage reservoir moves between a first position away from a sump panel opening defined by a steel making furnace and a second position adjacent the sump panel opening. A sump panel door is provided to open and close the sump panel opening. A sump panel door cover is also provided to cover a nozzle extending through the sump panel door. The sump panel door is positioned above the sump panel opening. The nozzle extends through the sump panel door and the nozzle directs a stream of the predetermined amount of sand into a tap hole within the steel making furnace when the sand storage reservoir is in the second position.
In some embodiments, the nozzle may define a first open end extending inwardly beyond a top interior surface defined within the furnace. The nozzle may define a second open end projecting outwardly from the furnace configured so that the second open end receives the predetermined amount of sand when the sand storage reservoir is in the second position. The second open end of the nozzle may define a funnel, preferably a funnel which tapers inwardly toward the internal elongated channel defined by the nozzle.
The sand dispensing system may include a sump panel door cover which moves between a first position for closing the nozzle when the sand storage reservoir is in the first position and a second position for opening the nozzle when the sand storage reservoir is in the second position.
Preferably, the sand storage reservoir is of a compact design, configured to dispense a predetermined amount of sand sufficient to fill the tap hole. In many instances, the reservoir will be configured to hold one predetermined amount of sand sufficient to fill the tap hole. Typically, the single predetermined amount of sand will be discharged into the tap hole when the movable sand storage reservoir is in its second position. The predetermined amount of sand may be variable so that, for example, the predetermined amount of sand held within the reservoir, and dispensed into the tap hole, is increased when needed as the volume of the tap hole increases over the life cycle of a tap hole sleeve. When a worn or damaged tap hole sleeve is replaced with a new tap hole sleeve, the predetermined amount of sand may be varied, usually by decreasing the predetermined amount, so that the amount of sand to be dispensed from the reservoir will be sufficient to properly fill the tap hole defined by the new tap hole sleeve.
In another aspect, the sand storage reservoir is configured to be mounted atop a sump panel on the steel making furnace so that the sand storage reservoir moves above the sump panel between the first position away from the sump panel opening and the second position adjacent the sump panel opening. The sand dispensing system may include a remote control or an automated control to operate:
In a preferred embodiment, the sand dispensing system, including the sand storage reservoir, is configured to be mounted atop the steel making furnace so that the sand dispensing system will tip along with the furnace during the operational movement of the furnace. Preferably, the sand dispensing system is secured to the sump panel of the furnace, so that the various moving components of the dispensing system may travel between their respective positions relative to the sump panel opening.
In another embodiment, preferably automated or remotely controlled at least in part, the sand dispensing system comprises:
Preferably, the nozzle extends into the interior of the furnace so that the nozzle extends inwardly beyond a top interior surface defined by the furnace. In some embodiments, a portion of the top interior surface of the furnace may be defined by an interior surface of the panel door cover which faces inwardly toward the interior of the furnace. The nozzle may define a funnel at one end to receive the predetermined amount of sand dispensed from the sand storage reservoir. Preferably, the opening area measured across the internal diameter of the nozzle defines a minor portion of the total area of the sump panel opening. In many instances, the internal diameter of the nozzle is about 5 to 6 inches for use in a sump panel opening with a diameter of about 18 to 20 inches. In those instances where the sump panel opening of a typical steel making furnace is shaped as a rectangle (including a square), the length of each of the sides will often be about 18 to 20 inches in length. In the most preferred embodiment, the internal diameter of the nozzle is less than the internal diameter of the opening in the tap hole. Preferably, the nozzle is configured to generate a cohesive stream of sand which has a diameter less than the diameter of the opening in the tap hole.
In some embodiments, the sump panel door may be cooled internally by cooling fluid circulating about the sump panel door, preferably adjacent to the portion of the nozzle which extends through the sump panel door. The sump panel may also be cooled to enhance operator safety when an operator approaches the sump panel opening to access the interior of the furnace or service other components, for example, the sand dispensing system and its components. The operation of the cooling features within the sump panel door may be used to inhibit the accumulation of metal flash or obstructions across or within the interior opening of the nozzle. Such cooling features may be useful in causing metal flash and other potential debris to fall away from the top interior surface, thus discouraging the formation of obstructions within the nozzle opening. In those instances where the sump panel door is not cooled internally, the nozzle may be elongated to form a collar within the interior of the furnace so that the collar extends inwardly beyond the top interior surface of the sump panel door, which is preferably recessed above the top interior surface of the interior furnace chamber. The collar may be configured to inhibit the formation of metal flash or other obstructions which could bridge an otherwise continuous interior planar surface extending across a flush nozzle opening defined by the interior surface of the sump panel door.
Preferably, the predetermined amount of sand is adjustable to offset a variation in the fill volume of the tap hole.
Preferably, the nozzle is sufficiently vertically aligned with the tap hole when the sand reservoir is in the second position, above the tap hole, to direct the cohesive stream into the tap hole. The nozzle is aimed to take into account the tilt of the furnace and the trajectory of the cohesive stream of the predetermined amount of sand when it is flowing into the tap hole.
Preferably, the predetermined amount of sand is released from the sand storage reservoir by opening a gate, into a funnel defined at a second end of the nozzle and through a first end of the nozzle which extends inwardly beyond a top interior surface defined within the furnace.
An imaging device may be remotely operated for remotely viewing the tap hole, through the nozzle, when the sump panel door cover is in the second position for opening the nozzle and the sand storage reservoir is in the second position.
Other embodiments of the invention, including other sand dispensing systems and other methods of dispensing sand into metal making furnaces, for example, steel making furnaces, will become apparent to those skilled in the art upon reading the specification of this application, including the description and drawings.
A preferred embodiment of the invention is illustrated and described herein having regard to the drawings in which:
In a preferred embodiment of the invention as illustrated in
The sand dispensing assembly 1 includes a dispenser ram housing 11 which in turn includes a stationary support column 17 and a movable reservoir assembly 12. In
In the fully fitted housing illustrated in
In this embodiment, the hinged sump panel door 20 may be opened by rotating the sump panel door 20 upwardly (preferably, via remote control), across the longitudinal axis defined by the length of the assembly 1, when the sump panel door cover 30 is retracted. In the preferred embodiment, cooling couplings 23 extend from the door 20, to allow cooling fluid to circulate through a cooling area extending through the interior of the door 20, adjacent and around the nozzle 21. As shown in
Preferably, the nozzle will be configured to have an internal diameter and shape to generate a focused, cohesive stream of a predetermined amount of sand to optimize the amount of sand needed to properly sand the tap hole of a furnace. Typically, tap holes are circular in cross section. Preferably, the nozzle in a sand dispensing system will be configured to generate a cohesive of stream of sand traveling along a suitable flight path (or trajectory) and having a suitable circular cross section with a diameter which is less than the internal diameter of the opening to the tap hole, to minimize overspray and accumulation of sand outside of the tap hole during the sanding step. To achieve such a cohesive stream of sand in the preferred embodiment, the nozzle will have a compatible internal shape and size consistent with the size and shape of the opening to the tap hole, to generate a cohesive stream of sand which will fall within the compatible target area defined by the tapered opening to the tap hole, and subsequently flow into the empty space within the tap hole.
To better illustrate the depicted embodiments, some of the components illustrated in the drawings, such as for example, the sand dispensing assembly 1 and the furnace 99 in
In
In
In
With reference to
The predetermined amount of sand may be measured and controlled at the sand reservoir assembly or elsewhere. For example, the volume of sand held within the sand box 3b of the sand storage reservoir 3 may be adjusted to be the optimal maximum amount of sand needed to sand a worn tap hole as it approaches the end of its working life. Preferably, the predetermined amount of sand will be adjustable so that an adequate amount of sand will be delivered to the tap hole, to ensure proper sanding of the tap hole. Preferably, the predetermined amount of sand will be adjustable from a remote location, from a remote control center. In some instances, it may be desirable to incorporate the volumetric control for sand into an automated control system for the sanding step.
As shown in the embodiment illustrated in
Various heat resistant, protective, and insulating materials may be used to make or assemble the components of the sand dispensing system, as would be evident to a skilled person.
In another preferred embodiment of the present invention, a method of dispensing sand into a tap hole within a furnace, such as a steel making furnace includes the following steps:
After the predetermined amount of sand is dispensed into the tap hole 90, the movable sand reservoir 3 is returned to its distal position, away from the sump panel opening 94. The sump panel door cover 30 is moved to cover the funnel opening 22 of the nozzle 21, to close the funnel opening 22 into the interior furnace chamber 50. Sand is recharged into the sand box 3b, preferably while sand reservoir 3 is in the distal position. Preferably, the amount of sand recharged into the sand box 3b is equal to the predetermined amount of sand. The predetermined amount of sand to be charged into the sand box 3b may be adjusted, if needed, in the preferred embodiment.
Preferably, an imaging device such as camera 8 is remotely operated for remotely viewing the tap hole 90, through the funnel opening 22 in nozzle 21. The camera permits a remotely located operator to view the tap hole 90 when the sump panel door cover 30 is retracted to open the funnel opening 22. The movable reservoir assembly 12, including the camera 8, are positioned in proper alignment above the funnel opening 22, to see into the interior furnace chamber 50, and particularly, to allow the operator to see the condition of the tap hole 90, before and after sanding of the tap hole 90.
Preferably, these method steps are controlled from a remote location. In some instances, the steps may be controlled by an automated control system programmed for variable operation and control from a remote location.
It should be understood that the above-described embodiment(s) of the present invention, particularly, any “preferred” embodiments, are only examples of implementations, merely set forth for a clear understanding of the principles of the invention. Many variations and modifications may be made to the above-described embodiment(s) of the invention as will be evident to those skilled in the art. For example, the order of steps listed in the preferred embodiment or other examples mentioned herein does not imply that the actual order of those steps must be carried out when the invention is implemented. Persons skilled in the art will appreciate that, in some instances, the order of such steps may be varied.
Where, in this document, a list of one or more items is prefaced by the expression “such as” or “including”, is followed by the abbreviation “etc.”, or is prefaced or followed by the expression “for example”, or “e.g.”, this is done to expressly convey and emphasize that the list is not exhaustive, irrespective of the length of the list. The absence of such an expression, or another similar expression, is in no way intended to imply that a list is exhaustive. Unless otherwise expressly stated or clearly implied, such lists shall be read to include all comparable or equivalent variations of the listed item(s), and alternatives to the item(s), in the list that a skilled person would understand would be suitable for the purpose that the one or more items are listed.
The words “having”, “comprises” and “comprising”, when used in this specification and the claims, are used to specify the presence of stated features, elements, integers, steps or components, and do not preclude, nor imply the necessity for, the presence or addition of one or more other features, elements, integers, steps, components or groups thereof.
Nothing in this specification or the claims that follow is to be construed as a promise.
The scope of the claims that follow is not limited by the embodiments set forth in the description. The claims should be given the broadest purposive construction consistent with the description as a whole.
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| Number | Date | Country | |
|---|---|---|---|
| 20160123668 A1 | May 2016 | US |
