JP2006161222A - Filter apparatus for molten polymer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter apparatus for a molten polymer, which is readily mounted on a molten polymer flow channel and replaced and further contributes to improvement of productivity. <P>SOLUTION: The apparatus has a tubular housing 2 equipped with a heater 4 and a filter pack 1 which is detachably inserted into the housing from above, is furnished with an inflow hole 6 and an outflow hole 7 connected to molten polymer transport tubes 60 and 70 on one side face of the housing 2 and with a pressing means 24 for pressing the filter pack 1 on the side face of the opposite side, with an inflow hole 10 and an outflow hole 11 on the side face of the filter pack 1 so as to respond the inflow hole 6 and the outflow hole 7 on the housing side and with a spacer 26 for position adjustments of the inflow holes 6 and 10 and the outflow holes 7 and 11 of the filter pack and the housing on the base side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a molten polymer filter device, and more particularly to an improvement of a molten polymer filter device incorporated as a prefilter in the middle of a flow path from a polymer melting portion to a spinning pack in a melt spinning machine.

  In the case of producing fibers with a melt spinning machine, it is indispensable to filter the solid foreign matters and gel-like foreign matters in the molten polymer before spinning in order to stabilize the quality of the fibers. Conventionally, a filtering means in a melt spinning machine is generally a filter in which a filter is incorporated in a spinning pack together with a spinneret.

  On the other hand, as the demand for fibers with fineness of 1 dtex or less increases in recent years, and as the spinning speed increases and the spinneret becomes more porous to improve productivity, it is necessary to strengthen filtration. It has become. In recent years, polytrimethylene terephthalate, which has been attracting attention because of its low Young's modulus, excellent tensile elastic recovery rate, and chemical stability, is easily pyrolyzed and easily produces a condensate of additive particles. Although it is a special polymer, even in the case of such a specific polymer, further filtration strengthening is required.

  However, the filtration method with a built-in filter in the spin pack as in the conventional melt spin pack cannot take up a sufficient filtration area due to restrictions such as the size of the spinneret. Therefore, the above special melt spinning is performed. In some cases, the filtration enhancement becomes difficult. For example, there is a method of making the filter mesh fine. However, simply by making the mesh fine, the initial filtration pressure loss becomes high, and the problem arises that the pack must be replaced in a short cycle.

  The limitation of such a filter with a built-in spin pack is that a filter device as disclosed in Patent Document 1 and Patent Document 2 is provided as a prefilter in the middle of the flow path from the polymer melting portion to the spin pack. Can be solved. However, since the conventional pre-filter type apparatus has the inflow hole and the outflow hole of the molten polymer on the opposite side surfaces, when this is incorporated in the middle of the polymer flow path, the polymer transfer pipe separated into the left and right It is sandwiched between the flanges attached to the end portions of each and fixed with bolts.

However, in order to replace the filter device sandwiched between the left and right flanges, it is necessary to remove the surrounding housing together with the heater and heat insulating material. This causes a drop in temperature and restarts spinning after the replacement. There is a problem that the time until the process is long and productivity is lowered. Also, because the work is performed when the molten polymer is at a high temperature, when loosening the bolts for tightening the flange, the molten polymer or gas generated by thermal decomposition is ejected, which is a dangerous operation and causes the extension of the replacement time. It was.
JP-A-8-10522 JP 2003-26721 A

  It is an object of the present invention to provide a molten polymer filter device that facilitates mounting and replacement in a molten polymer flow path in a prefilter type device and further contributes to improvement in productivity.

  The molten polymer filter device of the present invention that achieves the above object has a cylindrical housing provided with a heater and a filter pack that is detachably inserted into the housing from above, and the molten polymer filter is provided on one side of the housing. An inflow hole and an outflow hole connected to the transfer pipe are provided, and a pressing means for pressing the filter pack is provided on the opposite side surface so that the side surface of the filter pack corresponds to the inflow hole and outflow hole on the housing side. In addition, an inflow hole and an outflow hole are provided on the bottom surface, and spacers for aligning the inflow holes and the outflow holes of the filter pack and the housing are interposed on the bottom surface side.

  In the polymer filter device of the present invention, the filter pack can be detachably inserted from above into a cylindrical housing having a heating section, and only the filter pack can be taken out independently. It can be easily inserted and removed from above by being suspended by a crane or the like.

  In addition, since the inflow hole and outflow hole for the molten polymer are provided on one side of the housing and the filter pack, and the pressing means is provided on the opposite side, the inflow holes and the outflow holes can be formed only by pressing the pressing means. Sealing can be performed easily, and replacement can be performed in a short time of about several minutes.

  Further, when the filter pack is removed, if the pressing means is loosened while being housed in the housing, it is possible to avoid the ejection of the molten polymer or pyrolysis gas due to the residual pressure, and to work safely.

  Hereinafter, it will be specifically described with reference to a molten polymer filter device showing an embodiment of the present invention.

  In the molten polymer filter device of FIGS. 1 and 2, 1 is a filter pack, 2 is a housing, and 3 is a heating box. The housing 2 is formed in a cylindrical shape, a band-shaped heater 4 is wound around it, and the outside thereof is covered with a heat insulating material 5 of the heating box 3. The housing 2 is provided with a molten polymer inflow hole 6 and an outflow hole 7 on one side of the housing 2. In addition, molten polymer transfer pipes 60 and 70 are connected to the inflow hole 6 and the outflow hole 7 from the outside. The filter pack 1 is inserted into the housing 2 from above so that a height adjusting spacer 26 is sandwiched between the bottom surface and the bottom surface.

  Further, the upper surface of the housing 2 and the upper surface of the heating box 3 are respectively covered with an inner lid 27 and an upper lid 28. A temperature sensor 29 is embedded in the housing 2 so that the heating temperature by the heater 4 is controlled based on the detection signal. The heating temperature is arbitrarily set depending on the type of polymer and melt spinning conditions, but is generally 200 to 300 ° C.

  As shown in detail in FIG. 3, the filter pack 1 is configured by combining a pair of upper and lower cylindrical dividing members 8 and 9. The upper dividing member 8 forms a space 12 therein, and the space 12 is continuously formed with a cylinder whose diameter is successively reduced in three stages from the opening at the lower end to the upper side. An inflow hole 10 is provided on the side surface of the dividing member 8 so as to correspond to the inflow hole 6 on the housing 2 side. The inflow hole 10 extends so as to be orthogonal to the central axis of the dividing member 8 and It communicates with the top of the shape.

  On the other hand, the dividing member 9 on the lower side includes a base portion 9a having a large diameter and a rod-shaped filter mounting portion 9b having a smaller diameter. The base portion 9a is fitted into the middle cylindrical portion of the three-stage space 12 of the upper side dividing member 8, and the filter mounting portion 9b is inserted into the uppermost cylindrical portion. A female screw 13 is provided on the inner wall of the lowermost cylindrical portion of the space 12, and a ring-shaped fastening screw 14 is screwed to the female screw 13, so that the outer periphery of the upper surface of the base portion 9 a of the dividing member 9 is interposed via the packing 15. The space 12 is brought into close contact with the boundary between the middle cylinder and the upper cylinder.

  Further, the split member 8 is provided with a gate-shaped notch 16 at the lower part of the same side as the side on which the inflow hole 10 opens (see FIGS. 3 and 4), and the notch 16 is provided inside and outside the space 12. It penetrates. On the other hand, a projection 23 is formed on the base 9 a of the split member 9 corresponding to the notch 16, and the projection 23 is inserted into the notch 16 and engaged therewith. A molten polymer outflow hole 11 is opened at the end face of the projection 23 so as to face the outflow hole 7 on the housing 2 side. The outflow hole 11 extends in the base portion 9a toward the axial center, and further bends upward at the axial center so as to extend to the axial center of the filter mounting portion 9b.

  As described above, when the projection 23 of the dividing member 9 is engaged with the notch 16 of the dividing member 8, when the dividing member 9 is tightened with the tightening screw 14 to be brought into close contact with the dividing member 8, And the circumferential displacement between the outflow holes 11 and 7 is prevented.

  A plurality of vertical grooves 18 are provided in parallel to the axial direction on the surface of the filter mounting portion 9b, and a plurality of through holes 19 are provided at the bottom of these grooves so as to penetrate the inner outflow holes 11. A large number of leaf disk-like filter elements 20 are mounted on the filter mounting portion 9b having this configuration (see FIG. 5).

  The inner wall of the housing 2 is provided with a guide groove 21 that is directed downward from the upper edge of the inner wall and crosses the openings of the inflow hole 6 and the outflow hole 7 (see FIG. 6). A pressing means 24 is provided on the side of the housing 2 on the side opposite to the side where the inflow hole 6 and the outflow hole 7 are provided. The pressing means 24 is screwed to the side surface and is moved back and forth by turning.

  On the other hand, two protrusions 22 and 23 are formed on the side surface of the filter pack 1 at two upper and lower portions, and an inflow hole 10 and an outflow hole 11 are opened on end surfaces of the protrusions 22 and 23, respectively. The two protrusions 22 and 23 engage with the guide groove 21 on the housing 2 side, and as a result, the inflow hole 10 and the outflow hole 11 are displaced in the circumferential direction with respect to the inflow hole 6 and the outflow hole 7 respectively. I try not to wake you up.

  Further, when the pressing means 24 is rotated and moved forward to push the filter pack 1, the inflow hole 10 and the outflow hole 11 on the filter pack 1 side are respectively connected to the inflow hole 6 and the outflow hole 7 on the housing 2 side through the packing 25. In close contact. Since these protrusions 22 and 23 locally increase the pressing force of the pressing means 24, the sealing effect between the inflow holes and between the outflow holes can be further enhanced. The pressing means 24 can also be provided on the opposite side of the two protrusions 22 and 23, one at a time. However, as compared with the case where the projections 22 and 23 are provided on the opposite side corresponding to the center between the projections 22 and 23 as in the illustrated example, the work of turning the screw of the pressing means 24 is increased, and the tightening force may be unbalanced. Therefore, it is preferable to provide it at a position corresponding to the center between the protrusions 22 and 23 as in the example shown in the figure.

  Further, the spacer 26 inserted in the bottom surface of the filter pack 1 sets the height of the opening portions of the inflow hole 10 and the outflow hole 11 on the filter pack 1 side to the height of the opening portions of the inflow hole 6 and the outflow hole 7 on the housing 2 side. It is provided for adjustment to align. The height can be adjusted, for example, by setting the lower end of the guide groove 21 of the housing 2 to a predetermined height. However, the height adjustment by the lower end of the guide groove 21 causes the groove deformation and wear at an early stage because the filter pack 1 is very heavy, and the height direction between the inflow holes 6 and 10 and between the outflow holes 7 and 11 There is a disadvantage in that the positional deviation occurs earlier and the durability is inferior to the height adjustment by the spacer 26 described above.

  Filtration of the molten polymer by the filter device is performed as follows.

  The polymer melted in the polymer melting part such as ex and ruder flows into the space 12 of the filter pack 1 from the molten polymer transfer pipe 60 through the inflow holes 6 and 10. The molten polymer that has flowed into the space 12 is filtered from the outside to the inside through a filter element 20 in which a large number of layers are laminated, and then passes from the vertical groove 18 through the through hole 19 to the outflow hole 11 inside the filter attachment portion 9b. leak. Subsequently, it is discharged from the outflow hole 11 through the outflow hole 7 of the housing 2 to the molten polymer transfer pipe 70 and transferred to a spinning pack (not shown).

  When replacing the filter pack in the filter device described above, first, the pressing means 24 is loosened with the upper lid 28 and the inner lid 27 attached. By the loosening operation of the pressing means 24, it is possible to prevent the residual pressure of the molten polymer and the pyrolysis gas from leaking and the gas and the like from being ejected rapidly. Next, the upper lid 28 and the inner lid 27 are removed, the filter pack 1 that needs to be replaced is hung and taken out by a hoist crane or the like, and then a new filter pack 1 preheated in another place in advance is taken out. It is housed in the housing 2 while being suspended from above. Next, the pressing means 24 is tightened to seal between the inflow holes 6 and 10 and between the outflow holes 7 and 11, and finally the inner lid 27 and the upper lid 28 are attached. Thereby, the replacement work of the filter pack 1 can be performed in a short time of about several minutes.

  In the molten polymer filter device of the present invention, it is important that the molten polymer inflow hole and outflow hole are provided on the side surface on the same side with respect to the housing and the filter pack. The side surface in which the inflow hole and the outflow hole are provided is substantially parallel to the direction in which the filter pack is inserted into the housing. It is important that the pressing means is provided on the side surface of the housing opposite to the side surface provided with the inflow hole and the outflow hole as described above. Due to the arrangement relationship between the inflow hole and outflow hole and the pressing means, the inflow hole and outflow hole of the molten polymer can be easily sealed only by pressing the filter pack in the housing in one direction.

  The shape of the filter pack and the housing is preferably a columnar shape or a cylindrical shape, but may be a regular polygonal column shape or a regular polygonal cylinder shape (particularly a quadrangle or more). By adopting such a shape, the molten polymer inside the filter pack can be heated uniformly from the housing. Of course, the columnar shape or the regular polygonal column shape does not mean a geometrically perfect perfect circle or regular polygon, and it is allowed to have a partial protrusion or notch on the surface.

  The vertical alignment of the inflow hole and outflow hole on the housing side and the inflow hole and outflow hole on the filter pack side is performed by interposing a spacer at the bottom of the filter pack. Such vertical alignment is possible by engaging the guide groove provided on the inner wall surface on the housing side with the protrusion provided on the filter pack side, but those using the guide groove can be used for a long time. There is a drawback that the groove is deformed by the weight of the filter pack and a highly accurate seal cannot be secured.

  In addition, it is preferable that at least one of the inflow hole and the outflow hole provided in the filter pack is provided so as to open to a protrusion protruding from the side surface of the filter pack, and more preferably, both the inflow hole and the outflow hole are open to the protrusion. It is good to provide. In this way, the inflow holes and outflow holes are opened in the protrusions, thereby facilitating the positioning of the filter pack relative to the housing, and by concentrating the pressing force of the pressing means on the protrusions, In addition, the seal between the outflow holes can be ensured and strengthened. In the illustrated example, the pressing means generates a pressing force by the screw mechanism, but the means may be other means such as a hydraulic cylinder.

  In the example shown in the figure, the inflow holes and outflow holes provided on the side surfaces of the housing and the filter pack are on the upper side and the outflow holes are on the lower side. Alternatively, the outflow hole may be arranged on the upper side. In addition, regarding the divided members for assembling the filter pack, the vertical positional relationship in the illustrated example may be arranged such that the divided member 8 is on the lower side and the divided member 9 is on the upper side.

  The pair of upper and lower divided members constituting the filter pack have an assembly structure that fits each other, and the fitting portion is provided with a notch cut out from the end on the outer fitting side portion, and the inner fitting side portion. A projection is formed to project sideways, and the projection is engaged with the notch. With this structure, when the pair of upper and lower divided members are assembled by utilizing the rotation of the tightening screw, the inflow hole or the outflow hole is brought into the housing-side inflow by the rotation of the divided member in contact with the tightening screw. It is possible to prevent occurrence of a positional shift in the circumferential direction with respect to the hole or the outflow hole, and it is possible to configure a highly airtight filter pack.

  The type of the molten polymer to be filtered by the filter device of the present invention is not particularly limited, such as polyamide, polyester, polypropylene, etc., but is particularly suitable for filtering polytrimethylene terephthalate that is easily thermally decomposed and easily generates a condensate of added particles. . In particular, it is suitable for use in the production of fibers having an ultrafineness of 1 dtex or less.

  Polytrimethylene terephthalate is composed of a 1,3-propanediol component and a terephthalic acid component, but ethylene glycol, diethylene glycol, trimethylene glycol, cyclohexane diol, bisphenol A, bisphenol sulfone, EO adduct of bisphenol A, EO adduct of bisphenol sulfone, 1,4-butanediol, ε-caprolactone, isophthalic acid, phthalic anhydride, phthalic acid, succinic acid, adipic acid, 2,6-naphthalenedicarboxylic acid, sebacine Acid, 5-sodium sulfoisophthalic acid, 5-sodium sulfoterephthalic acid, 5-potassium sulfoisophthalic acid, 5-potassium sulfoterephthalic acid, 5-lithium sulfoisophthalic acid, 3,5-di (carbo-β-hydride Loxyethoxy) sodium benzenesulfonate, potassium 3,5-di (carbo-β-hydroxyethoxy) benzenesulfonate, lithium 3,5-di (carbo-β-hydroxyethoxy) benzenesulfonate, 5-sodium sulfoisophthalic acid Dimethyl, dimethyl 5-potassium sulfoisophthalate, dimethyl 5-lithium sulfoisophthalate and the like may be copolymerized.

  Further, titanium dioxide as a matting agent, silica or alumina fine particles as a lubricant, hindered phenol derivatives, coloring pigments, and the like as antioxidants can be added as necessary.

  The melt polymer filter of the present invention is particularly effective as a filter for melt spinning, but can also be applied to melt molding of general molded products such as plastic pipes and plastic plate materials. For melt spinning, it can be applied to both direct continuous polymer spinning and chip spinning.

It is a longitudinal cross-sectional view which shows an example of the molten polymer filter apparatus of this invention. It is AA arrow sectional drawing of FIG. It is a longitudinal cross-sectional view of the filter pack in FIG. FIG. 4 is a view taken in the direction of arrow B in FIG. It is principal part sectional drawing in the filter pack of FIG. It is a perspective view which shows the part of the guide groove provided in the housing inner wall face of the molten polymer filter apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Filter pack 2 Housing 3 Heating box 4 Heater 5 Heat insulating material 6, 10 Inflow hole 7, 11 Outflow hole 8, 9 Dividing member 9a Base part 9b Filter attachment part 12 Space 13 Female screw 14 Tightening screw 16 Space 18 Vertical groove 19 Through Hole 20 Filter element 21 Guide groove 22, 23 Protrusion 24 Pressing means 26 Spacer 27 Middle lid 28 Upper lid 60, 70 Molten polymer transfer pipe

Claims (5)

  A cylindrical housing provided with a heater, and a filter pack that is removably inserted into the housing from above; an inflow hole and an outflow hole connected to a molten polymer transfer pipe are provided on one side of the housing; A pressing means for pressing the filter pack is provided on the opposite side surface, an inflow hole and an outflow hole are provided on the side surface of the filter pack so as to correspond to the inflow hole and the outflow hole on the housing side, and the bottom surface side A molten polymer filter device in which spacers for aligning the inflow holes and the outflow holes of the filter pack and the housing are interposed.   At least one of the inflow hole and the outflow hole of the filter pack is opened to a protrusion protruding from a side surface, extends downward from the upper edge of the inner wall surface to the inner wall surface of the housing, and the inflow hole and outflow hole are formed on the bottom surface. The molten polymer filter device according to claim 1, wherein a guide groove is provided to be opened, and the protrusion is engaged with the guide groove.   The outer shell of the filter pack is a structure in which a pair of upper and lower divided members are combined, and a protrusion that opens the inflow hole or the outflow hole is provided on a side surface of one of the divided members. The molten polymer filter device according to claim 1, wherein the molten polymer filter device is engaged with a notch provided in the portion.   The molten polymer filter device according to claim 1, wherein the housing is covered with a heating box made of a heat insulating material. The molten polymer filter device according to any one of claims 1 to 4, wherein the molten polymer is polytrimethylene terephthalate or a copolymerized polymer having polytrimethylene terephthalate as a main component.

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