MXPA01006714A - Process and apparatus for filament winding composite workpieces - Google Patents

Abstract

A process and apparatus (10) are provided for forming filament wound composite workpieces (20). The process comprises the steps of:providing reinforcement material (40);providing an injection die (50);providing a winding apparatus (60) including a rotatable mandrel (62);passing the reinforcement material (40) through the injection die (50);injecting a resin material into the injection die (50) to impregnate the reinforcement material (40) with the resin material to form impregnated reinforcement material (40a);and winding the impregnated reinforcement material (40a) about the mandrel (62) so as to form a composite workpiece (20).

Description

PROCEDURE AND APPARATUS FOR WINDING WITH FILAMENT (S) OF COMPOSITE WORK PIECES TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY OF THE INVENTION This invention relates to a process and apparatus for winding with filament (s) of composite workpieces and more particularly to a process and apparatus wherein the reinforcing material is impregnated in an injection matrix before winding in a mandrel. BACKGROUND OF THE INVENTION When producing parts or pieces of work wound with filaments, continuous fibers are conventionally wound onto a mandrel in predetermined geometrical patterns using winding equipment. Fibers maintain the fibers and are used under tension. The mandrel can rotate or be passive. The orientation and thickness of the winding can be selected to correspond to the direction and magnitude of the loads in the final work part or part. Typically, high strength reinforcement or structural fibers such as glass fibers for example, glass E or glass S and aramid fibers, boron and carbon, can be used when producing parts or pieces of work wound with filaments. The fibers are impregnated with a liquid resin, such as polyester or an epoxy resin, by means of an impregnation bath or roller applicator. The fibers are wetted before being wound on the mandrel. To obtain the wetted, the fibers are typically passed through an impregnation bath or passed over an applicator roll. Full wetting and impregnation are difficult to achieve with these traditional methods. In addition, these methods often result in air trapped in the wetted reinforcement beam. Even at low speeds, these conventional wetting processes are only capable of wetting, impregnation and removal of air from a limited number of strands. Therefore, the speed of application of reinforcement material that can be incorporated within the sections wound with filaments, is limited. In addition, the parts wound with filaments are processed at relatively low speeds due to the slow speed of wetting, making these parts costly. Resin baths are open or partially open to the atmosphere resulting in significant emissions to the atmosphere of environmentally unfriendly volatile organic compounds or VOC's (volatile organic compounds). In addition, significant waste of resin commonly occurs with the use of open bath moistening methods. Gaps are commonly found in parts wound with filaments that are caused by air trapped in the resin loaded on the fibers as it passes through a resin bath or engages a roller applicator. Therefore, there is a need for an improved filament winding process and apparatus, whereby: (1) higher speeds of application of glass reinforcing material can be wetted to reduce the time required to form a filament wound part; (2) parts wound with filaments can be formed with a higher reinforcing content; (3) the gaps in the final work pieces can be reduced; (4) VOC emissions can be reduced; and (5) improved resin employment occurs. SUMMARY OF THE INVENTION The present invention provides an improved process and apparatus for winding filaments of workpieces or parts. It involves passing reinforcing materials, before winding in a mandrel, through a high pressure injection matrix where the reinforcing material is impregnated with resin material. The injection matrix is capable of increasing the rate of reinforcement application while providing complete impregnation of the reinforcement material. In addition, packages of reinforcing material having increased thicknesses and densities, which until now were not used in filament winding processes, can now be used. Also, resin materials that have high viscosities that, if used in an impregnation bath they would not have resulted in a complete impregnation within a reasonable period of time, now they can be used. The parts or work pieces formed by the process and apparatus of the present invention have small numbers of holes. In addition, less VOC's are released into the atmosphere since an open resin bath is not required. According to a first aspect of the present invention, a method for winding a composite workpiece with filament is provided. The process comprises the steps of: providing a reinforcement material; provide an injection matrix; providing a winding or winding apparatus including a rotating mandrel; passing the reinforcing material through the injection matrix; injecting a resin material into the injection matrix to impregnate the reinforcing material with the resin material, to form the impregnated reinforcement material; and winding the reinforcing material impregnated with respect to the mandrel so as to form a composite workpiece. The reinforcing material may comprise continuous fibers alone or in combination with articles in roll.

The articles in roll may comprise woven fabrics, non-woven fabrics, and needle punches, chopped strand mats, veils or combinations thereof. In one embodiment, when the reinforcing material comprises continuous fibers in combination with the articles in roll, the continuous fibers are under a first tension as they pass through the injection matrix and are wound onto the mandrel, and the articles in roll are under a second tension as they pass through the injection die and are wound onto the mandrel. The second tension is less than the first tension that allows the articles in roll to be incorporated in a filament winding process. The step of injecting a resin material into the injection matrix may comprise the step of injecting a single resin into the injection matrix. Alternatively, first and second resins can be injected into the injection matrix. The first resin can impregnate a lower portion of reinforcing material and the second resin can impregnate an upper portion of the reinforcing material. The first resin may comprise a corrosion resistant resin while the second resin comprises a less expensive resin. It is also contemplated that first and second resin systems may include an abrasion-resistant filler or filler, an ultra-violet degradation inhibitor or other functional additives with features that are advantageous for a portion of the total laminate construction. According to a second aspect of the present invention, an apparatus for filament winding of a composite workpiece is provided. The apparatus comprises an apparatus for supplying a reinforcing material and an injection matrix through which the reinforcing material passes and in which the resin material is injected. The resin material impregnates the reinforcing material. The apparatus further includes a winding apparatus positioned adjacent to the injection die. The winding apparatus includes a mandrel. The impregnated reinforcement material is wound around the mandrel to form a composite workpiece. The delivery apparatus includes a first tensioning device which causes the continuous fibers to be supplied under a first tension and a second tensioning device which causes the articles in roll to be supplied under a second tension, which is less than the first tension. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of an apparatus constructed in accordance with the present invention; and Figure 2 is a side view of the apparatus illustrated in Figure 1, with the mandrel, carriage and roll holder and creels removed. DETAILED DESCRIPTION AND PREFERRED MODALITIES OF THE INVENTION An apparatus 10 for winding filaments of a composite workpiece 20 is illustrated in Figure 1. It comprises apparatus 30 for supplying reinforcing material 40 and an injection matrix 50 through which the reinforcement material 40 passes and in which the resin material is injected. The resin material impregnates the reinforcing material 40. The apparatus 10 further includes a winding apparatus 60 positioned adjacent to the injection die 50. The winding apparatus 60 includes a rotating mandrel 62. The impregnated reinforcement material 40a is wound to the mandrel 62 to form the composite workpiece 20. The ro mandrel 62 in the illustrated embodiment is of the "continuous tape" type as described in US Pat. Nos. 3,464,879; 3,655,489 and 3,679,521, the descriptions of which are incorporated herein by reference. The mandrel 62 is defined by a continuously running steel strip 62c supported on an internal support structure (not shown) such that the band 62c moves continuously in a helical pattern from right to left as seen in Figure 1 The edges of successive sections 62b of the band 62a border one another to define an outer mandrel surface of helical path, cylindrical and continuous 62c. When a band portion reaches the end of the support structure, it is returned through the inner portion of the mandrel 62. The method for feeding the band 62a and the manner in which the return portions of the band 62a are placed and located to reconstitute the movable surface 62c, are fully described in patents "879," 489 and "521. As the web 62a advances, it is preferable to cover it with a separating layer, not shown, such as a plastic liner or laminate of relatively inert plastic, for example from MYLAR, in the form of a web that is wider than one of the web sections or widths 72b.The separation web is self-overlapping and provides a liquid-tight cover for the mandrel 62 as well as which provides a separating sheet for the subsequent separation of the surface of the mandrel 62c from the workpiece 20 which is constructed on the mandrel 62. Other commercially available winding devices 60 do not specifically described here can also be employed.

The delivery apparatus 30 in the illustrated embodiment comprises a carriage 32 which is capable of reciprocating back and forth or in both directions on the rails 34. Alternatively, the carriage 32 can be stationary. The carriage movement 32 is effected by a screw 35 or a spindle coupled to a gearbox 36. The gearbox 36 in turn is coupled to a pulse motor (not shown) by a band 37. An operator, at controlling the operation of the thrust motor and the gearbox 36, can cause the carriage 32 to reciprocate on the rails 34 at any speed or can cause the carriage 32 to stop when desired. The carriage 32 supports the reinforcing material 40, which may comprise articles in roll 42, continuous fibers 44 or a combination of both. In the embodiment illustrated in Figure 1, the carriage 32 includes a support 32a for a single roll 42a of the roll articles 42. It further comprises a guide eye board 43 for collecting multiple strands of continuous fibers 44 from the creels (not shown). ). The fibers 44 may comprise structural or reinforcing fibers such as glass fibers, for example E fibers or S fibers, aramid fibers, boron and / or carbon. The fibers 44 may also comprise composite strands such as the mixed polymer and reinforcing fiber strands described in US Pat.

No. 5,626,643, the description of which is incorporated herein by reference. It is also contemplated that the fibers 44 may comprise reinforcing fibers having polymeric (thermosetting or thermoplastic) material coated thereon such as those described in the U.S. patent applications. Nos. Nos. 08 / 769,340, 08 / 695,909 and 08 / 695,504, the descriptions of which are incorporated herein by reference. The articles in roll 42 may comprise a woven fabric, a non-woven fabric, a needled needle fabric, a chopped strand mat, a continuous filament mat, a web or any combination thereof. It is also contemplated that a thermoplastic material may be incorporated within the roll articles 42. For example, thermoplastic fibers, glass fibers coated with thermoplastic or thermoplastic particulate powders may be incorporated within a mat or fabric. In the embodiment illustrated in Figure 1, the fibers 44 pass through a guide and alignment device 32c and then combine with a single layer of articles in roll 42 to form a reinforcement package 41 that passes to the injection matrix 50. It is also contemplated that reinforcement package 41 entering matrix 50 may comprise only continuous fibers 44 or only articles in roll 42. Furthermore, it is contemplated that any number of layers of articles in roll and any number of layers in fibers they can be used to form the reinforcement package 41. The carriage 32 also supports the injection matrix 50. The injection matrix 50 can comprise any conventional injection matrix such as that described in the US patent. No. 3,556,888 granted to Goldsworthy, the description of which is hereby incorporated by reference. However, it is preferred that the injection matrix 50 comprises the matrix described in U.S. Pat. No. 5,747,075 granted to Gauchel et al., The description of which is hereby incorporated by reference. The "075 patent discloses an injection die having a structure comprising first and second substantially planar surfaces 16f and 18f for coupling opposing sides of the reinforcing material to compress the reinforcing material as it passes through the injection matrix. reinforcing material passes through the injection matrix, the resin material is injected into the matrix at a pressure of 7.03 kg / cm2 (100 psi) or greater, and more preferably in the order of 17.58 kg / cm2 (250 psi) ) or greater The injection matrix 50 comprises an input portion 52c, an internal passage 52b and an exit portion 52c. The reinforcing package 41 enters the matrix 50 through the input portion 52a. It is passed through the matrix 50 by the rotary mandrel 62. As the package 41 passes through the internal passage 52b of the matrix 50, it is poured and impregnated with a resin material. From the matrix 50, the impregnated pack 41a comprising the impregnated reinforcement material 40a is coiled with respect to the mandrel 62 to form the workpiece 20. The resin supply apparatus 54 is provided to supply the resin material to the matrix 50. , see Figure 2. The supply apparatus 54 comprises first and second supply lines 56a and 56b, supply devices 57a and 57b and heaters 58a and 58b. Each of the delivery devices 57a and 57b may comprise a conventional constant pressure pump. The resin system may already be a single resin composition injected into the matrix 50 through injection gates 59a and 59b or it may comprise different materials of multiple resins injected in the gates 59a and 59b. In this manner, a first resin material can be injected into the gate 59a to impregnate a lower portion 41c of the reinforcement pack 41, while a second resin material can be injected into the gate 59b to impregnate an upper portion 41b of the reinforcement pack. . The first resin material may comprise a corrosion resistant resin such as vinylester, commercially available from Dow Chemical under the product designation D-411, or an impact resistant resin such as vinylester urethane, commercially available from Dutch State Mining (DSM) . The second resin material may comprise a less expensive resin such as polyester or epoxy resin. The first and second resin materials may include an abrasion resistant filler such as sand or ceramic fillers or fillers, an ultraviolet degradation inhibitor such as Tinuvin P, commercially available from Ciba Geigy, a pigment and / or a gel coating. The first and second resins may comprise other commercially available thermosetting resins such as isophthalic polyester, phthalic polyester, a phenolic resin, polyurethane or polyisocyanurate. The matrix 50 is considered capable of impregnating reinforcement packages such as very dense packages, which until now were not used in filament winding processes, because the complete impregnation could not be carried out in a timely manner. Therefore, the present apparatus 10 is capable of forming coiled parts with filaments or workpieces having a high reinforcing content, for example up to about 100 kg / m2. In addition, the present invention allows the reinforcement package 41 to be more easily tailored for a desired product application since the package 41 can comprise combinations of reinforcement materials that were previously not used in filament winding processes. Also, since the package 41 is infused with resin under pressure, less air is trapped in the package 41 resulting in fewer gaps in the resultant filament-wound workpiece. It is also noted that VOC's are reduced and resin utilization is improved since open resin baths are not required. The carriage 32 further includes a plurality of tension bars 32d which couple the fibers 44 before they pass through the guide and alignment device 32c and into the injection matrix 50. Therefore, the bars 32d define a first device of tensioning which causes the continuous fibers 44 to be supplied under a first tension to the injection matrix 50 and the mandrel 62. The roller support 32a is also designed to create resistance to rotation, such that it comprises a second tensioning device that causes the articles in roll 42 to be supplied under a second tension. Preferably, the first voltage is greater than the second voltage. The articles in roll 42 can be damaged if they are supplied under a very high tension. The resulting workpiece can be constructed having between about 1 to about 20 layers of impregnated reinforcement material 40a. The impregnated reinforcement material 40a can also provide multiple layers when applied to the mandrel 60 by creating a reinforcing width greater than the feed speed of the mandrel 60 relative to the carriage 32. An oven (not shown) can be provided to cure the resin in the winding work piece 20 when a thermosetting resin is used. In addition, a cutting device (not shown) can be provided to separate the work piece 20 in desired lengths. It is also contemplated that one or more injection dies (not shown) may be placed on, below or to the side of the die 50. Each die receives a different portion of the reinforcement pack and impregnates that portion with one more resin materials. The two or more package portions may have different densities and constructions. The one or more resins that are provided to each matrix can be any of the resins discussed above. It is further contemplated that two or more injection matrices may be placed in series with each other. Both matrices can receive the same portion of the reinforcement package.

It is further contemplated that the reinforcement package may include an intermediate layer such as a foam layer or a highly charged intermediate layer such as an aggregate layer such as sand, with a single particle size or mixed particle sizes.

Claims (23)

1. CLAIMS 1. - A method for winding with filament (s) of a composite work piece, characterized in that it comprises the steps of: providing reinforcement material; provide an injection matrix; providing a winding apparatus including a mandrel; passing the reinforcing material through the injection matrix; injecting a resin material into the injection matrix to impregnate the reinforcing material with the resin material to form impregnated reinforcement material; and winding the impregnated reinforcing material relative to the mandrel so as to form a composite workpiece.
2. 2. The method according to claim 1, characterized in that the step of providing the reinforcing material comprises providing continuous fibers.
3. 3. The method according to claim 1, characterized in that the step of providing the reinforcing material comprises providing continuous fibers in combination with articles in roll.
4. 4. The method according to claim 3, characterized in that the articles in roll comprise woven fabric, non-woven fabric, needled needle fabric, chopped strand mat, veil or a combination thereof.
5. 5. The process according to claim 3, characterized in that the continuous fibers are under a first tension as they pass through the injection matrix and are wound on the mandrel, and the articles in roll are under a second tension as they pass through the injection die and are wound onto the mandrel, the second tension is less than the first tension.
6. 6. - The method according to claim 1, wherein the step of injecting resin material into the injection matrix comprises the step of injecting first and second resins not identical to the injection matrix, the first resin impregnates a lower portion of the reinforcing material and the second resin impregnates an upper portion of the reinforcing material.
7. 7. The method according to claim 6, characterized in that the first resin comprises a corrosion-resistant resin.
8. 8. The method according to claim 6, characterized in that at least one of the first and second resins includes an abrasion-resistant filler or filler.
9. 9. - The method according to claim 6, characterized in that the second resin includes an inhibitor of ultraviolet degradation.
10. 10. The method according to claim 6, characterized in that the second resin includes a pigment.
11. 11. The method according to claim 6, characterized in that the second resin includes a gel coating.
12. 12. - Apparatus for winding filaments of a composite work piece, characterized in that it comprises: an apparatus for supplying reinforcing material; an injection matrix through which the reinforcing material passes and in which the resin material is injected, the resin material impregnates the reinforcing material; A winding apparatus positioned adjacent to the injection die and including a mandrel, the impregnated reinforcement material is wound into the mandrel, to form a composite workpiece.
13. 13. - Apparatus in accordance with the claim 12, characterized in that the delivery apparatus provides reinforcement material comprising continuous fibers.
14. 14. Apparatus according to claim 12, characterized in that the delivery apparatus provides reinforcement material comprising continuous fibers in combination with articles in roll.
15. 15. - Apparatus according to claim 14, characterized in that the articles in roll comprise woven fabric, non-woven fabric, needled needle fabric, chopped strand mat, veil or a combination thereof.
16. 16. - Apparatus according to claim 12, characterized in that the delivery apparatus includes a first tensioning device that causes the continuous fibers to be supplied under a first tension and a second tensioning device causes the articles in roll to be supplied under a second tension, which is less than the first tension.
17. 17. Apparatus according to claim 1, characterized in that the step of providing an injection matrix comprises the step of providing an injection matrix having a structure for coupling opposing sides of the reinforcing material, in order to compress the material of reinforcement as the reinforcement material passes through the injection matrix.
18. 18. Apparatus according to claim 17, characterized in that the structure comprises first and second substantially planar surfaces.
19. 19. - Apparatus in accordance with the claim 12, characterized in that the injection matrix comprises one. structure for coupling opposite sides of the reinforcing material to compress the material as the material passes through the injection matrix.
20. 20. Apparatus according to claim 19, characterized in that the structure comprises first and second substantially planar surfaces.
21. 21. Apparatus according to claim 1, characterized in that the resin material is injected into the injection matrix with high pressure.
22. 22. Apparatus according to claim 21, characterized in that the resin material is injected into the injection matrix at a pressure equal to or greater than 7.03 kg / cm2 (100 psi).
23. 23. Apparatus according to claim 12, characterized in that the injection matrix comprises an injection matrix with high pressure.