US2428810A

US2428810A - Method and apparatus for fiberizing molten material

Info

Publication number: US2428810A
Application number: US485009A
Authority: US
Inventors: Edward R Powell
Original assignee: Johns Manville
Current assignee: Johns Manville Corp; Johns Manville
Priority date: 1943-04-29
Filing date: 1943-04-29
Publication date: 1947-10-14
Anticipated expiration: 1964-10-14

Description

Oct." 14, 1947; E; R. POWELL. 2,428,810

METHOD AND APPARATUS FOR.FIBERIZING MOLIEN MATERIAL Filed April 29, 1945 INVENTOR ATTORN EY Patented Oct. 14, 1.947

UNIT/EBB EA 10 Claims; 1,

The. present-- invention relates? to the: manu-. facture or-mineralwool and particularly to -improved apparatustfor convertingmolten raw -material=-intorfibers. The 'term mineral. wool is employed herein in a generic sensea-to include wool or fibers formed from rock, slag-glass; mixtures thereof and like raw materials Heretofore mineral wool .has' been made in". a number of ways including the conventional methe od ofdisintegrating molten "material into a :mul tiplicity of fibers bythe action of ahigh pressure steam jet. More recently'it has been proposed-to fiberize the moltenmaterial by the use of? a1 spinner or rotor rotated at high speed upon. which the material impinges and by which it is broken up into drops or masses which are thrown from the spinner by centrifugal. force to be drawn into fibenor. thread =form; The=principal object ofthe instant invention is the provision of animproved apparatus and method of the-lat= ter type.

Another objectof the invention is the vprovision-of 'arotortype fiberization apparatusofincreased fiber yield, and which will producea finer; more uniform fiber-than obtained byyprior prac= tice. 4

Further objects of the invention areethe provision of an apparatus including multiplerotors acting in succession on the molten material and ofimproved-rotor constructions and arrangements.

My-invention will be more fully understoodend further objects and advantages thereof will .be-' come apparent when reference is made to'the more detailed description thereof whichis to followand to the accompanying drawings; in which:

Fig. 1 is a diagrammatic elevational view-"il lustrating the arrangementof the material melting; and fiberizing -means;

Fig. 2 is -a-sectional view on an enlargediscale taken ona line 2-2 of Figgl; F1Fig. 3-isat0p'p1an'vieW of the apparatus' of Fig. 4wisia sectional .view onv an. enlarged scale taken. on 'a lined-4 of Fig: 2; and 1 Fig; 5 is a'sectional view similarf'toFigz'q' i1; lustrating the condition of the rotor surface's 'durr ing'ioperation.

Referring now to the drawingsthere' is shown an: apparatus comprising? armeltingfurnae I 0.

The furnace illustrated .isiof'the cupola'type but" it-willbe understood that anyyothersuitable meltingifurnace 'such' as a'tank furnace may be em= ployed, if desired. The furnaceincludes a discharge trough II by whicha'stream .of molten material-l 4=is vdrawn from theiurnace:and-tdis-- chargedein position; for fiberizationp The raw material meltedsinwrurnace vH1 may'comprise rock; slag glassxandvmixturesvthereof'l'or other thermoplastic materials employed in. the manufactu-re of mineral-wool; glass :wool and the like.

Be1o.w-=- theend .oi Ltrough l 2 and positioned 'to receive th'feemolten material isal fiberizing device indicatedigenerally atr I 6 and-, inaccordance with the invention, comprising-4a.. plurality of rotors. The rotorsaareindicatediat l8 and- 20 and are preterablyaot*cylindricalwshape though they may berslightlfconedii desired Rotor I8 is affixed to a sshaft-2 2-: for rotation therewith, the shaft being-,supportedvinsuitable bearingshzd carried by any desired mountings Rotor l8 is-positioned-to have itsperipherahsurface contacted by molten material stream l 4; Rotor l8 istilted with respeet tow'rotor-ill. The-particular degree of tilt of rotor: I8 :is notrcritical-within reasonable lim- "its but; iorrthe purposesof example, it may be stated-"that a tilt of':12 degrees fromthe vertical, where-rotorfl o is supportedon a horizontal axis, has beenrfounda satisfactorydrr-service. Rotor 2O isacarried rbyea;- shaft 26:-f or rotation therewith; the =shaft-beingasupported"inbearings 28, also carriedby;-any suitable mounting.- Shafts 22 andflfi are drivenbwa motor or other suitable means-(not'shown) for rotationin opposite d-irectionseand so that points on the upper arcs of the-periphriesof :the rotors approach each other, aseindicatedby the arrow-sin Figz2a The mounting of the shafts is such that the .spacing between ther rotorssas wellas=the angle between theeplanes :of-.=their-faces,may be varied as found necessary: ordesirable. X

Referrrnganow particularly -to 1Fig. 4,- the peripheralflsurfaceseof the rotors are provided with ae-succession of annular.- grooves'28. The grooves of rotor 20 are .suitably'vV-shaped .in cross-section and of relatively small uniformzsize; Rotor I8 is provided with ariewsomewhat larger and deeper:- ann-ular grooves 30; preferably rectangular in? cross-section; errand-adjacentthat portion of the rotor surface impacted by the stream of molten nslagi Ormther materiaL- l4,- with.which the viewed in Fig. 2. The adjustment also provides for the impingement of the molten material stream on that part of the rotor surface having the relatively deep grooves 39. Rotors |8jand are adjusted to provide a bight or spacethere- 4 given conditions. It will be understood that there is, in eifect, a relationship between these several factors which must be maintained Within reasonable limits. Also the molten material must be at a sufficiently high temperature to maintain the bonded rings in an incandescent state to permit the fiberization to take place. I i I The fiber formed, as described'above', may be collected in any suitable manner. Also, a binder may be introduced into the fiber, if desired, the particular construction and operation of binder addition and felting means not forming a part 7' of the instant invention.

115 between of approximately the combined thickness of the molten material built up on the rotors,

say, A;" to 37 and rotor I8 is tilted to. lie in a plane at an angle to the plane of rotor 20. Rotors l8 and 20 are driven in opposite directions, as previously explained, and at suitable peripheral speeds, depending upon the particular operating conditions such as the fluidity of the molten material. For purposes of example, it may be stated that in employing a conventional mineral wool. melt, successful operation was obtained bydriving rotors, approximately 11" in diameter and grooved as previously described, at 4500 R. P. M.

The molten material impinging on rotor I8 is partially bonded to the rotor'in grooves 30, the bonded material forming a relatively permanent non-stripping annular ring or rings 32 (see Fig. 5) revolving with the rotor. 'Most of the stream, however, is projected by the rotor almost tangentially to the surface thereof, at a greatly accelerated speed and in a slightly spreadcondition, onto the peripheral surface of the second rotor, as indicated in Fig. 2. The molten material bonds in the grooves of rotor 20 to provide an annular ring 34, the excess unbonded material being projected tangentially back to the first rotor. The bond of the material in the finer grooves 28 is of a relatively temporary nature and from time to time the material may strip from these grooves. However, after stripping, bonding of the material in the grooves will immediately be resumed. Due to the tilt of the first rotor relatively to the second, the material projected back strikes rotor l8 at a location laterally removed from the location of impact of the original stream to form a second annular'bonded slag ring 36 on rotor l8 (see Fig. 5).

The projection of the unbonded molten material from one rotor to the other may continue to form a third bonded ring 38 on rotor 20, as indicated in Fig. 5, and likewise in some instances may again be projected back onto rotor I8. In each case the additional ring will be laterally removed from the previous rings due to the relative tilting of the rotors.

When the remaining unbonded molten material reaches the bite between the rotorsit is leveled off and admixed instantaneously with'the material which has been carried around each rotor. As the rotor surfaces separate considerable fiberization takes place by the pulling of the material from the surfaces of the opposite rotors, the fibers being momentarily attached to both. The'molten incandescent material on the outer surface of

rings

32, 34, 36 and 38 is thrown oh by centrifugal force and drawn out into fibers due to the velocity of movement.

As has been referred to above, the peripheral speeds of the rotors, the fluidity of the melt and the grooving of the rotors, may be varied to meet The construction, as explained above,'has been found to deliver a greatly increased fiber yield over other rotor type fiberizing means as heretofore proposed Also, a relatively fine and uniform fiber is obtained different uses. 7 7

Having thus described my invention in rather full detail, it will be understood that these details need not be strictly adhered to, but that various changes and modifications will suggest themselves to one skilled in the art, all falling within adapting the product for many the scope'of the invention as defined by the sub} joined claims.

What I claim is: I

1. In a mineral wool apparatus including means for discharging a molten material streammany times larger than the fibers to be formed therefrom, a rotor of a character to withstand the heat of the molten stream positioned to receive said stream, means for rotating said rotor at high speed, a second, similar rotor adjacent, said first rotor but spaced therefrom and positioned to -receive molten material discharged from said-first rotor, means to rotate said second rotor at high speed and in a direction opposite to the'rotation of said first rotor, and means 'on said rotor surfaces to retain rings of the molten material thereon. f

1 2. In a mineral wool apparatus including means for discharging a molten material stream many times larger than the fibers to be formed there'- from, a rotor of a character to withstand the .at high speed in a direction opposite to the rotation of said first rotor, and means on said rotor surfaces to retain rings of the molten material thereon. I

3. In a mineral 'wool apparatus includin means for discharging a molten material stream many times larger than the fibers to be formed therefrom, a rotor of a character to Withstand the heat of the molten stream positioned to receive said stream, a second rotor of similar character and tilted with respect to said first-mentioned rotor and positioned to receive material discharged by said first rotor, means for rotating said rotors at high'speeds and in opposite directions and means on said rotors to retain rings of the molten material thereon.

4. In a mineral wool apparatus including means for discharging a molten material streardmany times larger than the fibers to be'form'ed' therefrom, a'cylindrical rotor having a forward face and including aperipheral surface of a charac ter to withstand the heat of the molten stream positioned to'receive said stream on its peripheral surface, means for rotating said rotor at high speed in one direction, a second cylindrical rotor of similar character adjacent but spaced from said first-mentioned rotor and having a forward face lying in a plane at an angle to the plane of the forward face of said first rotor, the line of intersectionof said planes passing through the axes of said rotors, said second rotor being positioned to receive on its peripheral surface molten material discharged from said first rotor, means for rotating said second rotor at high speed in a direction opposite to the rotation of said first rotor, and means on said surfaces of the rotors to retain rings of the molten material thereon.

5. In a mineral wool apparatus including means to discharge a molten material stream many times larger than the fibers to be formed therefrom, a rotor of a character to withstand the heat of the molten stream positioned to receive said stream on its peripheral surface, said surface including annular material-retaining grooves, means for rotating said rotor at high speed in one direction, a second rotor of similar character adjacent but spaced from said first rotor and positioned to receive on its peripheral surface molten material discharged by said first rotor, said surface of the second rotor having annular material-retaining grooves, and means for rotating said second rotor at high speed in a direction opposite to the rotation of said first rotor.

6. In a mineral wool apparatus including means for discharging a molten material stream many times larger than the fibers to be formed therefrom, a cylindrical rotor having a forward face and including a peripheral surface of a character to withstand the heat of the molten stream positioned to receive said stream on its peripheral surface, said surface having relatively large annular retaining grooves at the location of contact with said stream and relatively fine annular grooves on the remainder of said surface, means for rotating said first rotor at high speed, a second rotor of similar character adjacent but spaced from said first rotor and positioned to receive on its peripheral surface molten material discharged by said first rotor, said surface of the second rotor having annular relatively fine material-retaining grooves, means for rotating said second rotor at high speed in a direction opposite to the rotation of said first rotor, said second rotor having a forward face lying in a plane at a slight angle to the plane of the forward face of said first rotor.

7. In a mineral wool apparatus including means for discharging a molten material stream many times larger than the fibers to be formed therefrom, a rotor of a character to withstand the heat of the molten material supported on an axis at an angle to the horizontal and positioned to receive said stream on its peripheral surface, means for rotating said rotor at high speed, a second rotor of similar character adjacent but spaced from said first rotor and supported on a substantially horizontal axis and positioned to receive on its peripheral surface molten material discharged by said first rotor, means to rotate said second rotor at high speed, and means on said rotor surfaces to retain rings of the molten material thereon.

8. In a mineral wool apparatus including means for discharging a molten material stream many times larger than the fibers to be formed therefrom, a rotor of a character to withstand the heat of the molten material, means supporting said rotor on an axis at an angle to the horizontal and in position to receive said stream on its peripheral surface, said surface including annular material-retaining grooves, means for rotating said rotor at high speed in one direction, a second rotor of similar character, means supporting said second rotor on a substantially horizontal axis lying in a vertical plane substantially parallel to the vertical plane of the aXis of the first rotor and in position to receive on its peripheral surface material discharged by said first rotor, said surface of said second rotor including annular material-retaining grooves, and means for rotating said second rotor at high speed in a direction opposite to the rotation of said first rotor.

9. In a mineral wool apparatus including means for discharging a molten material stream many times larger than the fibers to be formed therefrom, a rotor of a character to withstand the heat of the molten material, means supporting said rotor on an axis at an angle to the horizontal and in position to receive said stream on its peripheral surface, means for rotating said rotor at high speed, a second rotor of similar character, means supporting said second rotor on a substantially horizontal axis lying in a vertical plane substantially parallel to the vertical plane of the axis of said first rotor and in position to receive on its peripheral surface molten material disincandescent rings.

charged by said first rotor, and means to rotate said second rotor at high speed in a direction opposite to the rotation of said first rotor.

10. A method of making mineral wool from a molten mineral material comprising discharging said material onto a peripheral surface of a rotor having means on said surface for retaining molten material thereon and rotating on an approximately horizontal axis, whereby a portion of the material is retained on said surface by said means in the form of an incandescent ring, and another portion is thrown off, intercepting said other portion on the peripheral surface of another rotor similar to said first rotor whereby an incandescent ring is formed on said second rotor, and rotating said rotors at sufficiently high speeds and in opposite directions to form fibers from said EDWARD R. POWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 998,358 Lessing July 18, 1911 1,459,947 Cronemeyer June 26, 1923 2,150,945 Slayter Mar. 21, 1939 2,243,122 Ramseyer May 27, 1941 674,718 Wegerif May 21, 1901 2,176,808 Young Oct. 17, 1939 2,315,735 Richardson Apr. 6, 1943