US3022539A

US3022539A - Apparatus for distributing a fluid medium to a plurality of spinning chimneys

Info

Publication number: US3022539A
Application number: US860137A
Authority: US
Inventors: William M Massey
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1959-12-17
Filing date: 1959-12-17
Publication date: 1962-02-27
Anticipated expiration: 1979-02-27

Description

M. MASSEY APPARATUS FOR DISTRIBUTING A FLUID MEDIUM TO A PLURALITY OF SPINNING CHIMNEYS Filed Dec. 17, 1959 Feb. 27, 1962 3 Sheets-Sheet 1 z N Q-L INVENTOR WILLIAM MOORE MASSEY ATTORNEY Feb. 27, 1962 w. M. MASSEY 3,022,539

APPARATUS FOR DISTRIBUTING A FLUID MEDIUM TO A PLURALITY 0F SPINNING CHIMNEYS Filed Dec. 17, 1959 3 Sheets-Sheet 2 WILLIAM MOORE MASSEY Ma. Wm

ATTORNEY Feb. 27, 1962 w M. MASSEY 3,022,539

APPARATUS FOR DEESTRIBUTING A FLUID MEDIUM TO A PLURALITY OF SPINNING CHIMNEYS Filed Dec. 17, 1959 3 Sheets-Sheet 3 INVENTOR WILLIAM MCORE MASSEY ATTORNEY United States Patent 9 3,022,539 APPARATUS FOR DISTRIBUTING A FLUID MEDIUM TO A PLURALITY F SPINNING CHIMNEYS William" M. Massey, Signal Mountain, Tenn., assignor to E. I. du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Filed Dec. 17, 1959, Ser. No. 860,137 4 Claims. (Cl. 18-8) This invention relates to the supply of a fluid medium such as air or other gas to machines for spinning filamentous material of polymeric nature comprising a plurality of quenching or processing chambers arranged in one or more rows.

In the melt spinning of filamentous materials of polymeric nature such as polyhexamethylene adipamide and the like, the molten polymeric material is extruded through a spinneret into a zone where it is quenched by a flow of a gaseous medium. This is described in US. 2,273,105, W. W. Heckert, to Du Pont in which the use of a plenum chamber is disclosed and a plate or screen to provide suitable diffusion of the gaseous medium is interposed between the plenum chamber and the quenching zone. If a plurality of such units are uniformly supplied with equal quantities of cooling medium in parallel, however, disturbances of flow in any one of the plurality of units will affect the quantity supplied to the other units in the system to a considerable degree resulting in defective production of the spinning material. Minor disturbances of the type just described may be overcome by the placing of suitable orifices at the entry to each individual plenum chamber. In the course of operation, however, the difiusing plates or screens in the individual chambers become more or less clogged with extraneous matter and, to produce the desired quality in the spinning material, must be cleaned from time to time Removal of any one of these diffusing plates or screens has been found to cause such a large disturbance in the air flow that despite the use of orifices in series with the individual plenums suitable to maintaining uniformity between those units the remaining other units are adversely affected with regard to the quantity of air received.

The object of the present invention is to provide a novel and useful apparatus for distributing a fluid medium especially of gaseous nature such as cooling air or evaporative medium supplied to a plurality of chimneys for melt or dry spinning so that the amount of the medium supplied to each individual chimney supplied differs as little as possible from that supplied to the other chimneys regardless of individual position along the supply manifold.

A further object is to provide 'a compact physical arrangement of individual chimneys and fluid supply systems.

Still another object is to so supply fluid medium to the individual units that maintenance operations at a particular chimney such as cleaning or the like may be accomplished with a minimum of disturbance to the other spinning positions in the system.

These and other objects will become apparent in the course of the following description and claims.

In accordance with the present invention a multistation fluid treating system is provided comprising a common fluid supply means, a plurality of distributing means dependent therefrom and at least one fluid treating station dependent from each of said distributing means wherein the pressure drop between the fluid supply and each of the distributing means is at least 12 and not more than 18 times the pressure drop between each distribution means and its dependent treating station and wherein the pressure drop between any one distributing means and its treating station may be made to approach zero Without substantially changing the flow rates existing in the other distributing means and their dependent treating stations. In terms of a spinning machine for the production of synthetic fibers such a device comprises a plurality of spinning chimneys and a duct system for distributing fluid medium to the said spinning chimneys, the said system comprising a manifold of decreasing cross-sectional area, an inlet for the said medium at the large end of the said manifold, plenums spaced along the said manifoldtat varying distances from the said inlet, an outlet for the said medium from the said manifold to each plenum, an outlet from each plenum to each spinning chimney, fluid flow restricting means at each plenum outlet to provide pressure in the said plenum during flow of the said fluid and fluid flow restricting means at each manifold outlet to provide pressure in the said manifold during flow of the said fluid, the relationship of the flow restricting means at the manifold outlet to the flow restricting means at the plenum outlet such that the pressure drop from the manifold to the plenum is from about 12 to about 18 times the pressure drop from the plenum to the spinning chimney during fluid flow.

,The invention will be more readily understood by reference to the drawings.

FIGURE 1 is a perspective view in partial cross section of several of a plurality of plenum chambers and their associated manifold and chimneys.

FIGURE 2 is a detailed front elevational view in cross section of a fluid outlet from the manifold to a plenum.

FIGURE 3 is a view in perspective and partial cross section of another embodiment of a spinning machine according to the present invention. I

FIGURE 4 is a side elevational view in cross section of one quenching chamber supply system taken on the line 44 in FIGURE 3.

FIGURE 5 is a cross section of an elastomeric gasket shown in FIGURE 4.

FIGURE 6 is a plan view in cross section of one of the chimneys of the apparatus of FIGURE 1.

Referring to FIGURE 1, the spinning machine comprises a tapered manifold 1 having an inlet 2 for receiving fluid medium from a conventional pressure distribution system not shown and a multiplicity of fluid medium outlets 3 between manifold 1 and each of a series of

plenums

4, 5 and 6 distributed along manifold 1 at varying distances from inlet 2. Each plenum supplies a flow of the fluid being distributed across one or a multiplicity of chimneys 7 in a direction normal to the longitudinal axis of the said chimneys, the fluid flow being vented to the atmosphere through screens 8. Chimneys 7, detach ably mounted by fastening device 9 to mounting plate 10, have the side containing screen 8 hinged at 11 for ready access to the chimney tube during operation and preferably, a glass observation port 12 for inspection purposes during operation of the machine. In operation air under relatively low pressure, say two to three inches of water, is admitted to manifold 1 and flows in the direction of the arrow. The pressure distribution system not shown may conveniently consist of a blower, some form of filtration and some form offlow measuring equipment, all of which are upstream of inlet 2. The manifold is tapered in accordance with the well-known principles of static regain so that the regain of static pressure as velocity is lost in the direction of flow, is just enough to overcome the effect of friction, but is not greater than this and so does not cause uneven distribution. It is of course understood that the exact number of plenums may be fewer or greater than the three shown. Each plenum may supply a multiplicity of chimneys 7 (four being shown in the figure), into the open top of which an tapered sections of these chambers,

"fluid then flowsinto four chimneys per plenum passing extrusion of liquid (i.e. molten or in solution) synthetic fiber-forming polymer, not shown, is introduced. The transverse flow of fluid from the plenum meets and solidifies .the extrudate in the chimney converting the extrudate to fiber. The fiber, not shown, is removed through a cut-out in the bottom of the chimney. Fluid in plenum 4 is maintained above atmospheric pressure by means of distribution metering plate 13 over which diffuser screen 14 is mounted- Both metering plate 13 16 are so selected that a large pressure drop occurs at' this point. The pressure drop across screen 17 is slight and its purpose is to diffuse the upwardly directed jets of fluid. Upstream from plate 16 there may be an air straightener 18 which, as shown, is a piece of honeycomb metaL' Thus the flow is from manifold 1 through air straightener 18 through metering plate 16 and ,then through diffuser screen 17.. In mounting the outlet, gaskets or sealing compounds are employed to prevent leakage'at the joints.

After leaving diffuser screen 17 the fluid stream in the plenum or,6 (FIGURE 1) is divided by the V- shapedxupper surface of these chambers, through the As illustrated the through meteringplate 13 and diffuser screen 14 as previously described. Plate 13 provides a pressure drop suitably large to permit even distribution of flow from chimney to chimney within a'plenum. group but never-- theless small in comparison with the drop across manifold outlet 3. Flowin the individual chimneys is then directed by thevertical sides of the chimneys toward the hinged sides previously described and finally is vented from the apparatus through screens 8. a

, FIGURE 6 is a more detailed representation of chimney 7. As shown in this figure the chimney 7 of rectangularcross section has one side hinged at 11 for'ready access to the chimney tube during operation. It is removably mounted via mounting plate upon'plenum 6, framing plenum outlet port 15. Gasket retaining plate 19 along with a bottom plate and a top plate not shown are welded to plate 19 to form a cavity holding elastomeric gasket 20 in which metering plate 13and diffuser screen 14 are .mounted. When fastening device 34 which may be a block of metal retaining a rotatable bolt that screws into a tapped hole in the mounting plate 10 is employed to fasten the assembly-to the chimney mount- 7 ing plate 10, gasket 2 is compressed, thus being firmly retained and also acting as a seal. The structure may bereinforced top and bottom in the back and at thetop in the front by means of angles such as 21. A rigid bottom plate 22 is permanently fastened to the sides of chimney 7 andforms a cut out 23 at its point of junction with movablebottom plate 24 fastened to the hinged side Cut out 23 permits passage of the of'the chimney. filamentous material being processed from chimney 7. In another embodimenhasshown in FIGURES, manifold 1 supplies tapered plenum :4, flow passing in'the direction of the arrow through'manifold metering plate 16, plenum metering plate 13, and diffuser screen 14. Thetrapezoidal shape of chimney 7-, fashioned to be removable as a complete unit, produces a textile yarn of particularly high uniformity. FIGURE 4 is a sectional elevation across lines 44 of FIGURE 3. As shown in FIGURE 4, a gasket 33 is interposed between manifold 1 and. plenum 4, securing metering plate 16.

4 4. This diffusing screen, having bound edges in the-manner well known to the art, is attached to the inner walls of plenum 4. Between the inner wall and the outer wall of the plenum, insulating material 25 may be interposed. The assembly is conveniently supported by suspension from frame 26 of the spinning machine. Plenum metering plate 13 and diffuser screen. 14 are held in an elastomeric gasket 20, shown in crosssection in FIGURES. This gasket has relieved grooves for the purpose of receiving and gripping metering plate 13 and diffuser screen 14 and may be of molded or laminated construction. It isretained in a cavity formed by the outer wall of plenum 4 and is slightly oversize in that cavity. The

attachment of chimney 7 to plenum '4 by means of fas-' tener 27 (FIG. 3). serves to compress gasket so that it acts as both a retainer for

plates

13 and 14 and as a seal between the chimney'7. and plenum 4. Chimney 7,

- when located by fastener 27, butts against the spinning head 28 of the spinning machine and a tight contact is maintained by gasket 20. Door 29 is hung on hinge 11 to close the front. of the chimney. The slots shown may be obtained by fastening transparent plastic strips 39 on the door leaving spaces between for the controlled outflow of the fluid medium. Manifoldl may be covered with insulation indicated by 31 and may be strengthened at intervals by reinforcements 32 (FIG. 3). a

The following table indicates the relative pressure drops in the system. Velocities through the holes are also shown.

T able Pressure Hole, Unit drop in velocity,

. g f.p.m.

Manifold plate 16 -Q. 2. 0s 4, 000 Lift iser screen 17.- 0.03 250 Plenum plate 13---. 0.126 1, OQO Diffuser screen. 14 n 0. 016 300 It will be seen then that the-ratio of the drop from the manifold into theplenum chamber to the drop from the plenum to atmosphere is 2.08 to 0.142 or.14.6 to l. V

This system, then, provides uniform flow from unit to unit despite small changes in the individual units. Furthermore, the high ratio of pressure drops in this case is such that any one of the individual plate and screen assemblies can be removed disturbing operation'only of the three units within that plenum which ordinarily are removed for cleaning'at the same time. The other plenum chambers on the ducts will be affectedonly'to a negligible degree. Where eight plenurns per duct have been employed, opening one plenum. entirely causes a variation of less than {4% in each of the other seven. Experience in the operationof units of this type has shown that the preferred range for pressure drop ratios is from 12:1 to 18:1 with 14:1 preferred. It has further been found that for best results, plenum air velocity must be kept equal to or less than A that through the chimney plate, which should be kept within the; range of 1000 to 2000 'f.p.m.

Many equivalent modifications will be apparent to those skilled in the art from a reading of the above without a departure from the inventive concept.

What is claimed is;

1. A spinning machine for theproduction of synthetic fibers which comprises a plurality of spinning chimneys and a duct system for distributing fluid medium to the said spinning chimneys, the said system comprising a manifold of decreasing cross-sectional area, an inlet for the said medium at the large end of. the said manifold, plenums spaced along the said manifold at varying distances from the said inlet, an outlet for the said medium from the said manifold to each plenum, an outletfrom each plenum to each spinning chimney, foraminous fluid flow restricting means at each plenum outlet to provide pressure in the said plenum during fiow of the said fluid and foraminous fluid flow restricting means at each mani fold outlet to provide pressure in the said manifold during flow of the said fluid said foraminous fluid flow restricting means at each manifold outlet being provided with a permeability of from about 12 to about 18 times the permeability of the foraminous flow restricting means of each plenum outlet.

2. The spinning machine of claim 1 wherein the forminous fluid flow restricting means at each manifold outlet is provided with a permeability of about 14 times the permeability of the foraminous flow restricting means of each plenum outlet.

3. The spinning machine of claim 1 wherein the crosssectional area of the plenum decreases along the path References Cited in the file of this patent UNITED STATES PATENTS Heckert Feb. 17, 1942 Lodge June 20, 1944 Miller et al Dec. 2, 1952 Curtis Aug. 11, 1953