Coating apparatus – Projection or spray type – Applying solid particulate material
Patent
1995-11-14
1997-12-09
Czaja, Donald E.
Coating apparatus
Projection or spray type
Applying solid particulate material
118323, 118306, 118669, 118681, 2940218, 266231, F27D 136
Patent
active
056955588
DESCRIPTION:
BRIEF SUMMARY
This invention relates to the repair of vessels, and particularly refractory-lined vessels.
With refractory-lined vessels such as are used in steelmaking, such as for example, furnaces, ladles, tundishes, and the like, it is inevitable that there is wear of the refractory lining. Frequently, the wear on the lining is insufficient to justify the costs of complete relining of the vessel, but is greater than is permitted to allow the vessel to be re-used without repair.
With such as, for example, an electric arc furnace, there are known locations on the lining where greatest wear takes place, on the wall of the lining in closest proximity to each of the three electrodes ordinarily employed, and circumferentially of the lining at the slag line. Similar considerations can apply to other vessels, such as basic oxygen furnaces where there are two principal points of wear of its lining at diametrically opposite locations on the line of the axis through the trunnions.
Conventionally, localised repair is effected by so-called gunning techniques, where a slurry of a required refractory material is directed at the wall through a nozzle at the end of a supply hose. In some circumstances the nozzle is hand-held requiring the operative to position himself above the furnace with its roof removed, both hazardous and inefficient because of inconvenient positioning of an operative relative to the required area where repair is required. In other circumstances a nozzle is provided on a carrier to locate the nozzle within the furnace, with a means to enable the nozzle to be driven arcuately. Whilst avoiding operator difficulties effective equipment is expensive, and relatively inefficient, with noticeable constraints on the volume/weight of refractory material that can be dispensed in unit time.
There are other known forms of equipment involving a spinning disc below a dispensing hopper, to be lowered into the furnace, with a series of movable gates associated with the spinning disc attempting to control the direction in which material deposited on the disc will be discharged against the furnace wall. Given the nature of refractory repair material, equipment of this nature is prone to becoming blocked, with jamming of the gates open or closed, and with the frequent need for it to be stripped and cleaned. It is also the case that the gates cannot be a sliding sealing fit on the rotating member, allowing refractory material to pass below a closed gate and simply fall to the floor, a wasteful loss of refractory material. In addition, the placement of a hopper and its associated rotatable disc within a vessel must be by an overhead crane. Overhead cranes in steelmaking plants are in constant use, and there is a considerable inconvenience in having the overhead crane out of commission whilst it is holding the hopper in the vessel for the time required for repair of the lining to be completed.
With vessels such as, for example, steelmaking furnaces, it is traditionally so that a bank of loose course granular refractory material is deposited as a bank at the junction of the furnace side walls and furnace floor to provide a smooth transition from the furnace wall to the furnace floor. During steelmaking there is inevitable erosion of the bank, frequently requiring its repair or renewal before the furnace can be re-used. Accurate deposit of fresh granular material to a bank at its points of required repair has similar and comparable difficulties with those mentioned above in connection with lining repair.
The object of the present invention is to provide for the repair of refractory lined vessels free from those disadvantages mentioned above.
According to the present invention, means to enable the repair of a refractory lining of a metallurgical vessel comprises a rotatable member, rotatably mounted at or towards the end of a carrier means adapted to locate the rotatable member at a required position in the vessel, a drive means for the rotatable member, means operable to activate the carrier to direct and deposit a particulate refracto
Czaja Donald E.
Monocon International Refractories Limited
Padgett Calvin
LandOfFree
Vessel repair does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vessel repair, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vessel repair will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1604217