US1650136A

US1650136A - Means for blowing mineral wool

Info

Publication number: US1650136A
Authority: US
Publication date: 1927-11-22
Anticipated expiration: 1944-11-22

Description

Nov. 22, 1927. 1,650,136 A. KOBERLE I MEANS FOR BLOWING MINERAL WOOL Filed June 10, 1926 Al (017mg.

I NVEN TOR.

BY M

ATTORNEY.

Patented Nov. 22, 1927.

* UNITED, STATES PATENT OFFICE,

ALBERT KOBERLE, or Los nnsnnns, CALIFQRNIA, Assienon, BY MESNE ASSIGN- MENTS, TO L a W CORPORATION, A CORPORATION or CALIFQRNIA.

l MEANS FOR BLOWING MINERAL Application filed June 10,

The present invention relates to the art of blowing mineral wool from molten slag and pertains more particularly'to means for subjecting molten slag to the action of air blasts and the like.

It will be'understood in the consideration of the invention that the commercial value of mineral wool is greatly reduced by the presence of small spheroids of chilled slag, commonly called shot. The insulating value, as well as the longevity of wool, as an insulator,'is greatly reduced by the presence of such shot. The shot not only represent a waste of material, but act as an abrasive and settling agent to cause the fibers to gradually break down and settle, with the result that the insulating value is lost. Numerous other disadvantages of the existence of shot "are recognized, and in fact mineral'wool containing an appreciable percentage of shot has little'or no market value. Manufacturers of mineral wool are compelled to subject the wool to various treatments to finally ob tain' a relatively small percentage of shotless wool. In any and all of such known treatments the fibers are short and broken.

There are various theories extant as to the mother stream, string out into afiber. which still connects the said globule to the V stream. If the globule is too large it will fore it is entirely spun out. The unspun head forms one of the most objectionable forms of shot. Other globules seem to leave the stream without spinning a thread behind them. Such globules chill and form round shot. The shot are so small and numerous and so intimately commingled with the fibers that separating .at any time is a task which is costly and destructive of the wool.- The r great problem in blowing mineral wool has been to subject all the slag to the proper acf tion from a jet of air, steam or the like, so that the globules will be sufficiently well subdivided and properly acted on as to be effec tually spun into fibers without leaving a head of any appreciable size. Low velocity blasts leave much ofthe slagunspun, and high 1 velocity blasts hit the slag so suddenly that a lose its velocity, or the fiber will break, be-

1926. Serial No. 115.014.

large percentage of spheroids are torn from the stream without apparently forming any fiber at all. Round jets, ribbon-like jets, and

completely enveloping annular jets have been i' employed for blowing slag, butit is found in all cases that a large percentage of the slag is torn from the stream in such manner that only shot, or partially spun fibers, result.

It is the principal object of this invention to provide methods and means for subjecting all the slag to the action of air jets, with a view to spinning all the globules into fibers without leaving shot or heads of any comwith the changes which may occur in the size, viscosity, and other observable characteris I tics of the slag stream.

Other objects and advantages of my inventionwill occur hereinafter. I I

Ihave illustrated my invention by the accompanying drawings, in which z Figure 1 is a plan view of a nozzle constructed in conformance with the invention.

Figure 2 is a view in longitudinal section thereof. 1

Figure 3 is an end elevation of the said embodiment.

g In carrying out'my invention in the embodiment shown, I provide a central nozzle 5, which, as will appear hereinafter may be of almost any suitable type; the principal requirement of said central nozzle being that it shall be capable of forwardly impelling or blowing a stream of slag, such as indicated bythe numeral 6. Preferably, for the sake of minimum air consumption, the nozzle orifice 7 is simply a long narrow slit adapted to discharge a flat ribbon-like jet of air.

Single nozzles, somewhat similar to nozzle 5, with thin orifices, have been employed for blowing wool, but the objection to such nozzles, and all single nozzles, is that much of the slag is forinedinto shot.

The slag is shown as falling a short dis horizontal.

tance, and it is a practical consideration that the slag will always have a tendency to penetrate the air jet to a certain extent, or even pass through it. Slag which has passedbelow the normal plane of the jet has acquired a forward impetus. The result is that such slag is carried forward by the stream at a reduced velocity, is not sufliciently subjected to the jet, and eventually chills in the form of shot or partially spun fibers. Some portions of the slag stream, particularly that around the outer circumference, is readlly forwarded by the jet and even has a tendency to be driven away from the jet at an angle without being properly spun, in fact, the stream when hit by the air jet, has a tendency to fan out in both directions. some of the slag, however, traveling directly forward. It is commonly observed that the slag travelin more nearly forward with the air stream is more thoroughly spun. The foregoing facts are mentioned concerning the nozzle 5 in order that the relation to and cooperation with, the other parts which I am about to describe, may be better understood.

Nozzle 5, may be variously formed, but in the embodiment shown it is tubular with the forward end flattened, as shown. In fact the nozzle comprises merely a piece of pipe with the forward end gradually changing from round to oval cross section, as at 8, and from oval crosssection to the slit-like orifice 7.

This form of nozzle seems best suited to delivering a ribbon-like jet with requisite spreading tendency.

The complete embodiment of the invention includes two other nozzles, 10 and 11,

respectively, hereinafter known as the-side nozzles. Said nozzles also have the slit-like orifice 7, but the orifices of the side nozzles are vertically directed on their major axes,

while the major axis of the central nozzle is The side nozzles are likewise formed by flattening the forward end of an otherwise round tubular member, but in shaping said nozzles it is preferable to have the outer surface, such as 12, undergo more change than the inner surface 13.

The side nozzles are converging forwardly with regard to each other. Thus the side nozzles provide two converging jets of air which meet and tend to cross at a pointforwardly of the nozzles orifices. It is obvious that such meeting of the converging streams,

as at 14, will produce a vortex or meeting point of great activity, but the tendency of all. the air will still be to travel in a general forward direction, particularly since the angle of convergence is not relatively great. The tendency of the air to continue forwardly is further aided by the jet from the central nozzle.

Referring to Fig. 3, it will be seen that the nozzles are so arranged that the orifice of the central nozzle comes between the orifices of the side nozzles, and the plane of the horizontal orifice is above the lowermost terminations of the vertical orifices.

In the embodiment illustrated, the central nozzle is inclined upwardly-forwardly, while the side nozzles are horizontal. In conformance with another salient feature of my invention, the side nozzles are advanced with regard to the central nozzle. It will be apparent, therefore, that as the axis of a jet which issues from the central nozzle reaches the advanced point at which the side nozzles eject the air, the center of the horizontal air jet will be more nearly midway of the upper and lower extremities, respectively, of the vertical air jets.

Various means for holding the nozzles in correct relation may be employed. In the development of this invention, the nozzles were made adjustable relative to each other, but for given production conditions they may all be fixed with regard to one another. Each nozzle is preferably provided with a separate valve 16, for throttling or controlling the amount of air used. If the stream of slag is light, less air is needed through the central nozzle than when the stream is heavy. in the embodiment being described the nozzles are all connected with a common chambered member 17, which is fed by a single air hose 18. ,By holding the chambered member rigid, all nozzles are held correctly relative to the stream. It is understood that it is best to provide any wool blowing nozzle with means for moving it about to follow changes in the direction of the slag stream, but such means are familiar to those skilled in the art and accordingly none are shown or described herein.

The slag may be delivered to the nozzle from any suitable means located above the nozzle, Fig. 2 showing a smelting furnace 20 as being directly above the nozzle and provided with a lip 21, over which the slag flows from the interior thereof. The nozzle is so positioned that the slag stream will fall in an approximately vertical direction toward a point just forwardly of the horizontal nozzle, and therefore, between the two side nozzles and the rear of the side nozzles orifices. The side nozzles act as guards for the slag stream and for the jet of air issuing from the central nozzle.

Since the nozzles are practically individual there is chance for ample flow of induced air around the nozzles, and particularly between the converging side nozzles. As the slag steam falls toward the horizontal air jet (see Fig. 2) it is first affected by air flying from the jet at an angle. It is also further affected by induced air flowing forwardly. Therefore. it seems that the tendency of the stream is to change gradually from vertical toward horizontal. Some of the slag, as explained, may even pass slightly below thercenter of the stream, but the forward impetus received by the jet itself and by the induced air, results in its being carried into the vortexcaused by the converging jets. I

It is to be noted, particularly, that the slag will have received considerable forward impetus before it can in any way be acted on by the jets issuing from the side nozzles. Hence the importance, in this embodiment, of having the central nozzle retracted with regard to the side nozzles.

Of course the results of the three air jets meeting as they do defy description, and it is suffioient to say that all the slag, at one time or another, before clearing the said vortex or meeting point of the jets, is subjected to the blasting effect of the air from almost all sides. The product of the three air jets and the slag stream is that of a high grade of fibers in which the percentage and size of shot is reduced to a point to where it is of no commercial objection.

Those skilled in the art, and in fact all persons who have seen mineral wool blown, are aware that when a common air blast hits a stream of slag, a myriad of sparks are seen to travel in a generally forward direction. These sparks, which are observed to fall short, will be seen to chill into shot, and in fact, I have concluded that all incandescent globules, which fiy from or with the blast, eventually form shot. When my improved nozzle is correctly operated the only manifestation on the forward, or the leeward, side of the vortex, is that of a bluish .haze, evidently the fibers actually being spun out. Large drops of molten slag, and smaller drops of incandescent slag in the form of sparks are reduced to a negligible degree, and in designing or adjusting a nozzle, any inefiicienoies manifest themselves by an appearance of sparks.

It will be understood that while I have spoken of air jets, any suitable gas, vapor or the like, under pressure, may be used for blowing the slag; steam and super-heated steam being among those suited, and while I have shown and described a specific embodiment for carrying out my invention, and specific procedure or method, I do not limit myself to any embodiment, or arrangement of parts, or arrangement of individual nozzles, nor do I limit myself to the method set forth, and I may alter the nozzle and the method as I desire, or as occasion requires,

without enlarging the scope of my invention and Without departing from the spirit thereof, within the appended claims.

I claim 1. In a device for blowing mineral wool, a bottom nozzle having a horizontally elongated orifice, and a pair of 'side nozzles, one to each side of said bottom nozzle; each side nozzle having a vertically elongated narrow orifice disposed forwardly of the orifice of said bottom nozzle; said side nozzles converging forwardly and the orifices of said side nozzle extending in a substantially vertical plane both above and below the plane of the orifice of said bottom nozzle.

2. In a device for blowing mineral wool, a bottom nozzle having a horizontally elongated orifice, and a pair of side nozzles, one to each side of said bottom nozzle; each side nozzle having a vertically elongated narrow orifice disposed forwardly of the orifice of said bottom nozzle; said side nozzles converging forwardly and the orifices of said side nozzle extending in a substantially vertical plane both above and below the plane of the orifice of said bottom nozzle; said bottom nozzle being directed upwardly forwardly with regard to said side nozzles.

3. In a device for blowing mineral wool, a bottom nozzlehaving a horizontally elongated orifice, and a pair of side nozzles, one to each side of said bottom nozzle; each side nozzle having a vertically elongated narrow orifice disposed forwardly of the orifice of said bottom nozzle; said side nozzles converging forwardly and the orifices of said side nozzle extending in a substantially Vertical plane both above and below the plane of the orifice of said bottom nozzle; and regulating valves, one for each nozzle and each valve being operable independently of the others.

4. In a device for blowing mineral wool,

a bottom nozzle having a horizontally elon- 100 gated orifice, and a pair of side nozzles, one to each side of said bottom nozzle; each side nozzle having a vertically elongated narrow orifice disposed forwardly of the orifice of said bottom nozzle; said converging forwardly and the orifices of said side nozzle being directed upwardly forwardly with regard to said side nozzles; and regulating valves, one for each nozzle and each valve being operable indes 110 pendently of the others.

ALBERT KOBERLE.

side nozzles