US2793395A - Apparatus for forming mineral wool - Google Patents

Description

May 28, 1957 c. D. RICHARDSON. 2,793,395

APPARATUS FOR FORMING MINERAL WOOL Filed Feb. 15, 1954 2 Sheets-Sheet 1 INVENTOR ATTORNEY May 28, 1957 c. D. RlcHARDsoN 2,793,395

APPARATUS FOR FORMING MINERAL WOOL Y Filed Feb. l5, 1954 2 Sheets-Sheet 2 INVENTOR C. z'ca'rdson ATTORNEY United States Patent APPARATUS FOR FORMING MINERAL WOQL Charles D. Richardson, Muncie, Ind., assigner to Charles Richardson Corporation, Muncie, Ind.

Application February 15, 1954, Serial No. 410,085

4 Claims. (Cl. lgs-2.5)

This invention relates to the manufacture of mineral wool and constitutes an improvement over my pending U. S. application, Serial No. 295,528, liled June 25, 1952, now U. S. Patent No. 2,689,373, yof which the present application is a continuation-impart.

In this pending case, molten slag is fed to a rapidly spinning disk, is 'centrifugally thrown therefrom, and the spun-off slag is subjected to a steam blast from a nozzle surrounding the disk, the spun-off slag being thus cooled and attenuated into long fibres. A stream of the molten slag from a cupola descends somewhat in front of the rotating disk and is sucked back onto the latter due to vacuum or the low pressure` zone created by the centrifugal action of the spinning disk and the aspirating effect of the steam blast from the nozzle. As operation is dependent upon this vacuum activity or sucking back of the molten slag stream, it follows that this stream must be relatively small or it will not be sucked back. Consequently, the cupola must be operated at low output with less of efficiency, and the spun fibre output is not ras great as could be desired during any period of time.

In the operation of a cupola it is very diflicult to run a small hot stream of slag unless the amount of fuel used is increased. That is, one must use much more fuel to hold xthe cupola in condition during the running of a small stream .of slag. If a small stream is run to a spinner it must be kept very hot or it will be too cold Ias it leaves the disk, resulting in undesirable fibres. If it is run onto the disk too hot, il Will be too hot as it leaves the disk and again undesirable libres will be formed of a soft dense nature unless the slag can be cooled after it leaves the disk and before-it is struck by the jets. 'Thedeal condition is -when the cupola can be operated at a Very high rate of production. Then the fuel ratio will be very low. That is, the amount of coke used will be very low in comparison to the amount of slag melted. Usually about 6 parts slag to 1 part coke. The amount of slag melted will be approximately 6,000 lbs. per hour. This high output from the cupola in the presence of vacuum activities could not heretofore be utilized for fibre spinning but the present invention makes this possible.

In order to utilize the larger and hotter stream of molten slag from the cupola operating at a high rate of production, the molten slag thrown olf by the spinning disk must be cooled before it is subjected to the steam blast, to prevent the formation of too dense, short, and soft fibres. Then, too, in order to get the large stream of molten slag onto the spinning disk, a force other than the vacuum or suction previously relied upon must be employed. The present invention fullls both of these requirements.

The axis of the spinning disk is placed at an inclination of from 30 to 45, air under pressure is supplied around the periphery of this disk, thus insuring that the previous low pressure or vacuum zone shall not exist, and the large stream of molten slag is run by gravity Ialone, directly onto the disk. Thus, the volume of slag which may be spun during a given period results in an fice increase of the volume of fine libres produced, and the cupola may be operated at high eiiicieney and, moreover, a high grade product will be produced.

In the drawings: f

Fig. 1 is a side elevation of the improved apparatus;

Fig. 2 is an enlarged vertical sectional view through the spinning disk, the rotary head of which it forms a part, the air supply means, and the steam nozzle;

Fig. 3 is a front elevation of the assembly shown in Fig. 2; and

Fig. 4 is a transverse sectional view on line 4T4 of Fig. 2.

Preferences have been disclosed in the drawings and will be rather specifically described, but it is to be understood that variations may be made without departing from the spirit and scope of the invention as claimed.

A tubular shaft 5 is rotatably mounted in bearings 6 on an inclined plate 7, said plate being hinged at 8 to 'a supporting frame 9 for vertical pivotal adjustment. A slotted link 10 and thumb screw 11 are provided for holding the free end of the plate 7 after adjustment.

A motor 12 is mounted on a bracket 13 projecting downwardly from the plate 7, and said motor is belt-connected at 14 with the shaft 5 to drive the latter. The front end of this shaft is provided with a spinning head 15 and the best results are attainable when the axis of said shaft and head is disposed 'at an inclination of from 30 to 45.

The spinning head 15 is shown as comprising a cylindrical side wall 16 having a flange 1-7 at its front end, a rear wall 18 having a boss 19 threaded onto the shaft 5, and a spinning disk 2 0 secured to said flange 17. The head is locked to the shaft by means of a lock nut 21. Cooling water is conducted to the head by means of the shaft 5 and from said head through a central pipe 22. A water supply hose 23 and a return hose 24 are connected with the shaft 5 and pipe 22, respectively, by means of a suitable coupling 25.

V*An air `conducting casing 26 surrounds the spinning head 15 and has a cylindrical side -wall 27 and a rear wall 28x. The front end ,of the side wall 27 is outwardly spaced from the peripheral edge of the disk 20 to provide a cir,- cular air discharge slot 29. The rear wall 28 is disposed behind the lock uut 21 and has a central opening 30 through which the shaft 5 passes. The end wall 28 also has a circular series Of arcuate slots 31 to admit air to the casing 2,6. This casing is rigidly mounted on the plate 7 by means of suitable brackets 32. 4

A valve ring 33 lies against the rear side of the casing end wall 2S `and is formed with a circular series of arcuate slots 34 for coaction with the slots 31 in controlling the amount of air admitted to the casing 26 for discharge through the slot 29. The valve ring 33 is manually rotatable to vary the amount of air admitted and may be locked 'after adjustment by means of screws 35. These screws extend through arcuate slots 36 in the valve ring 33 and are threaded into the casing end wall 28.

A suitable valved connection 37 is provided for conducting air under pressure into the `casing 26 to augment the supply of air through the slots 31.

A hollow nozzle ring 38 surrounds the front end portion of the casing side wall 27 and is rigidly joined thereto. Steam under pressure is supplied to this nozzle ring through a hose 39. The front wall 40 of the nozzle ring 38 has an almost circular series of steam jet discharge openings 41 but a zone 42 of said wall 40, directly above the axis of the spinning disk 20, is left imperforate, in order that no discharge of stream jets shall strike the stream 43 of molten slag running onto said disk 20. At opposite sides of the zone 42, the nozzle ring front wall 40 has perforations 44 which discharge steam jet curtains at opposite sides of the stream 43 and thus to a large extent prevent the molten slag, flying tangentially from the disk 20, from striking said stream 43. The axes of the openings 41 decline forwardly at an angle of about 30 to the axis of the shaftv and spinning head 15 to more or less horizontally discharge the steam jets against the molten slag thrown off by the disk 20, thus confining the spun fibres to a substantially horizontal path.

The apparatus is so placed with respect to the cupola 45 that the discharge from the latter may, With the aid of a trough 46, be directed straight down by gravity onto the spinning disk in the form of a stream 43. As no vacuum or suction is relied upon to pull this stream back onto the disk, said stream may be much larger than heretofore, the cupola may be operated more eiciently, and greater output in volume of fibres, during any given period, will be produced.

In operation, a tine spray of very hot slag is thrown oi tangentially by the spinning disk 20. The steam jet evacuates the air in front of the nozzle which induces a ow or rush of air through the surrounding slot 29 and this air current chills the fine spray of slag to such an extent that it will be thoroughly fiberized by the action of the sleeve-like blast of steam issuing from the openings 41. The speed of the disk 20 must of course be adjusted to the viscosity of the slag and the valve ring 33 must be adjusted to admit air to the casing 26 in proper quantity for best results.

The steam blast directs the fibres substantially horizontally into a suitable setting chamber 47 which is provided with a conveyor belt 48 to carry away the massed fibres for packaging or further processing.

From the foreging it will be seen that novel and advantageous provision has been made for attaining the desired end. While preferences have been disclosed, attention is again invited to the possibility of making variations. Also, it may be stated that hot compressed air instead of steam may be supplied to and discharged from the nozzle 38.

Iclaim:

1. An apparatus for spinning mineral wool from molten slag comprising a spinner rotor having an inclined front face, means for rotating said spinner rotor, means for dropping a stream of molten slag onto said front face from above said face to cause said spinner rotor to throw o a spray of molten slag, means at the periphery of said spinner rotor for directing a concentrated, annular sleevetype current of cool air transversely of the spray as it leaves the peripheral edge of said face for reducing theA temperature of said spray, means interposed in said sleevelike current of air to `control the movement of said current of cooling air, and means encompassing said air directing means for directing a sleeve-like blast of hot fluid under pressure against said cooled spray for final forming of the wool tibers. l

2. An apparatus as set forth in claim l, wherein the means encompassing said air directing means comprises an annular nozzle, said nozzle having fluid discharge openings so directed as to discharge the hot uid'horizontally.

3. An apparatus for spinning mineral wool from molten slag comprising a spinner rotor having an inclined front face, means to rotate said spinner rotor, means for die recting a stream of molten slag onto said front face from above said face to cause said spinner to throw of a spray of molten slag, a casing surrounding said spinner rotor defining therewith an'air passage, said casing having a cylindrical side wall spaced from and concentric with the periphery of said spinner rotor, the rear end of said casing having air inlet means and the front end of said casing having a restricted annular opening around said rotor, whereby said casing will direct a sleeve-like current of cool air against the slag spray to chill the latter, means interposed in said air passage for controlling the amount of air moving through said passage, and annular nozzle means spaced outwardly from said annular Iopening for directing a sleeve-like blast of hot fluid under pressure against the chilled spray.

4. An apparatus for spinning mineral wool from molten slag comprising a spinner having an inclined front face, means to rotate said spinner rotor, means for directing a stream of molten slag onto said front face to cause said spinner to throw off a spray of molten slag, a casing surrounding said spinner, said casing having a cylindrical side wall spaced from and concentric with the periphery of said spinner, the rear end of said casing having air inlet means and the front end of said casing being open, whereby said casing will direct a sleeve-like current of cool air against the slag spray to chill the latter, and annular nozzle means at the periphery of said casing for directing a sleeve-like blast of hot fluid under pressure against the chilled spray; said casing having a rear wall, said air inlet means of said casing comprising a circular series of arcuate slots in said rear wall, and a valve ring having a corresponding series of arcuate slots, said valve ring being turnable to register greater or lesser portions of its slots with the slots of said rear wall.

References Cited in the le of this patent UNITED STATES PATENTS

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