Method for producing a component using a heating device in the supply system

Abstract

The invention relates to a method for producing a fiber-reinforced component, wherein a textile made of reinforcing fibers is treated with a thermosetting matrix material in a matrix impregnation step. At least one direct supply system (3) is located between a storage container (2) and an impregnation unit (1), and the matrix material reaches the impregnation unit from the storage container through the at least one direct supply system. The method is characterized in that each of the at least one supply systems has at least one heating device (4), and according to the method for producing the fiber-reinforced component, the thermosetting matrix material is heated to a temperature required for the impregnation of the textile made of the reinforcing fibers with the matrix material solely in the at least one supply system by means of the at least one heating device of the at least one supply system.

Description

[0001] Process for component production with heating device in the supply system

[0002] Description:

[0003] The invention relates to a method for producing a fiber-reinforced component in which only a small portion of the required matrix material needs to be heated. Furthermore, the invention relates to a supply system for use in the method, which has a corresponding heating device, and to a system for carrying out the method with such a supply system. Furthermore, the invention relates to a storage container for the method and the system.

[0004] Methods for impregnating textiles to produce fiber-reinforced components are generally known. Systems used for impregnation are also known. EP 3 390 023 proposes an impregnation method in which the matrix material is frozen. The matrix material is fed in portions into an extruder equipped with heating devices that heats the matrix material to impregnation temperature. The aim of the method according to EP 3 390 023 is to not have the matrix material stored at room temperature. DE 10 2005 053 690, for example, describes a tool, an arrangement, and a method for producing a component. In the method, a storage bag filled with resin is placed in a storage chamber. The storage chamber is in contact with a working chamber containing a semi-finished product.The storage bag is made of a thin-walled material and contains the amount of matrix material required for component production. The storage chamber can be pressurized with compressed air, or the working chamber can be evacuated. In both cases, the resin material heated in the storage chamber flows from the storage bag into the working chamber to produce the component by impregnation. A similar process is also known from document EP 2 956 3820. This describes a collapsible bag packaging and a connection system, whereby the bag can be filled, for example, with a matrix material and emptied manually or by the pressure of a pump (compression pressure or vacuum). Document EP 0 370 564 describes the production of a storage bag for plastic material and the subsequent use of the storage bag.To produce a package, the storage bag is placed in or near the production mold such that an outlet opening of the storage bag lies in an injection channel. Pressure is then exerted on the storage bag and the processing material enters the cavity of the production mold. US Pat. No. 6,071,457 discloses a device consisting of at least a storage container, a supply system, and an infiltration tool. In an RTM (Resin Transfer Molding) process, the volume of the storage container can be reduced so that the infiltration material passes from the storage container into the production cavity via the supply system. US 2005 / 0023712 discloses a feed system for liquid resins (such as epoxy). The system has a storage bag for storing the liquid material, which can reduce its volume (for example under pressure) to improve the dispensing of the material.An improved resin delivery system is also described in document US 2019 / 0152111.

[0005] A disadvantage of some of the processes and systems from this state of the art is that the material used for impregnation (resin or matrix material) is heated as a unit and completely to the processing temperature (in the corresponding material storage container). During a longer impregnation process, the appropriate temperature of the matrix material must be maintained throughout the entire process, and temperature fluctuations must be prevented. This is associated with high energy costs, and temperature fluctuations in the matrix material can lead to undesirable side effects that could pose a safety risk (uncontrolled exothermic reaction). Furthermore, many reactive matrix materials age so quickly at the processing temperature that, once heated, matrix residues must be discarded and cannot simply be used in another process.In addition, the complete heating of the entire matrix material as a unit leads to the initial crosslinking reactions of the matrix material, depending on the selected matrix material, beginning without the textile being impregnated. This can lead to equipment contamination (or damage) and the production of components of poor product quality. This can only be prevented by choosing matrix systems that crosslink slowly, which disadvantageously increases the process time for component production.

[0006] Although the process according to EP 3 390 023 does not heat the entire matrix material in one heating step (but only in portions), the matrix material must be frozen, and the material must be cooled in a longer process to ensure that the matrix material remains frozen. In both cases, this requires energy and time. Heating the matrix material to the impregnation temperature then requires more energy than using the material at room temperature.

[0007] Document US 2004 / 0070114 discloses a system and method for an RTM technique, wherein a fiber material is to be processed. The system has two storage containers for resin material, various supply line systems, and a plurality of heating elements. The heating elements are provided on the storage containers and melt only the upper layer of the resin material within the storage containers, so that this layer can then be pumped out of the storage container. Consequently, the resin material within the storage container is inhomogeneously heated. The resin material is fed via a first supply line, via a subsequent supply line to the further supply line, and from there into the mold. All supply lines each have heating elements. Document EP 2 656 991 describes a storage container (for example in the form of a bag) for a device for casting resin processing and a corresponding method therefor.According to this document, a casting resin is fed to a mold for component production via at least one feed device. Excess casting resin is to be collected in a storage container that is connected to both the feed device and the mold. The storage container serves as a buffer for reactive casting material, whereby excess casting resin can be conveyed from the storage container into the mold as needed. The reactive mixture can also be passed through a heat exchanger, wherein the heat exchanger is provided in the storage container and / or the feed device. Document US 6,136,236 discloses a method and apparatus for impregnating a fiber pellet. The fiber pellet is to have a fiber content of more than 58%, and the document focuses on varying the pressure during impregnation.The resin material is located in a storage container and is fed into the mold via a feed line. A heat exchanger is provided within the feed line and is intended to ensure that the resin material is at the correct temperature before reaching the mold. The document US 6,168,408 discloses a device for impregnating composites, wherein the flow rate of the impregnation material and the pressure can be adjusted depending on the product to be impregnated. The device has at least one storage container, a feed system, and at least one mold. The storage container(s) are located in a tank, which is also suitable for heating the storage container(s). The feed system can have a heat exchanger. The document US 5,518,388 discloses a device and a method for RTM. Here, resin in a storage container is fed to a mold via various feed lines. The storage container and the mold can be heated via heating elements.The device also has a preheater, which is also intended to heat the resin.

[0008] A disadvantage of the described processes, however, is that the matrix material is fed from a storage container through a system of supply lines to the product to be impregnated, and the temperature required for impregnation must be maintained using heat sources. However, highly reactive matrix systems in particular are difficult to process in this way, as the risk of premature crosslinking within the supply system is too great.

[0009] It was therefore the object of the present invention to eliminate or at least mitigate the disadvantages occurring in the prior art.

[0010] This object was achieved by a method according to claim 1.

[0011] According to the present invention, a method for producing a fiber-reinforced component is proposed, in which a textile made of reinforcing fibers (so-called high-strength fibers) is treated with a thermosetting matrix material in a matrix impregnation step. The thermosetting matrix material required for impregnation is stored in a storage container, and the textile made of reinforcing fibers is stored in an impregnation unit, with at least one direct feed system provided between the storage container and the impregnation unit. The thermosetting matrix material passes from the storage container directly into the impregnation unit through the at least one direct feed system, with each of the at least one direct feed systems having at least one heating device.In the process for producing the fiber-reinforced component, the thermosetting matrix material is heated exclusively in at least one direct supply system by the at least one heating device to a temperature required for impregnating the textile made of reinforcing fibers with the thermosetting matrix material. During the process, the thermosetting matrix material is present in the storage container at room temperature, where room temperature is defined as a temperature between 16°C and 26°C. In one embodiment, the matrix material is present at a room temperature between 20°C and 25°C.

[0012] According to the invention, the thermosetting matrix material (hereinafter also referred to simply as matrix material) is not completely heated as a unit or is completely frozen as a unit. Advantageously, only the portion of matrix material that flows into the impregnation unit through at least one direct feed system is heated. Advantageously, this requires less energy to heat or cool the matrix material because a larger amount of matrix material does not have to be kept at the processing temperature or in a frozen state over the entire process period and then heated to impregnation temperature. Furthermore, the new process is also suitable for highly reactive matrix materials because the thermal pre-stress of the material, in particular the time between heating and impregnation, is particularly short.In addition, the thermosetting matrix material is to be fed directly to the impregnation unit, which also reduces the residence time of the matrix material in the feed system. Due to the short residence time of the matrix material within the feed system and the short time in which the matrix material is heated to an impregnation temperature, this system also allows the use of so-called highly reactive two-component resin systems without the second component having to be added separately at a later time. A further advantage of the new process can be seen in the fact that matrix material that was not (actually) required for impregnation was generally not heated to the impregnation temperature and can therefore be used without problem in another process. This reduces the amount of matrix material waste.

[0013] According to the invention, a direct supply system is used between the storage container and the impregnation unit, and the thermosetting matrix material is conveyed directly into the impregnation unit via the direct supply system and heated exclusively there (to an impregnation temperature). Such a system and such transport expressly excludes the matrix material being conveyed via a plurality of supply lines arranged consecutively (in a line). Accordingly, the matrix material can be transported directly from the storage container to the impregnation unit via a plurality of direct supply systems, but each direct supply system represents the shortest connection between the storage container and a selected area of ​​the impregnation unit.A transfer of the matrix material from a first supply system to a subsequent supply system and then to the impregnation unit is therefore not a direct supply system within the meaning of the invention. A system in which the matrix material is supplied to the impregnation unit via various (storage) containers arranged one behind the other via supply systems is also not within the meaning of the invention. The direct supply system according to the invention is intended to transport the matrix material from the storage container to the impregnation unit via the shortest route and as quickly as possible. Preferably, the residence time of the matrix material within the supply system is no longer than the time required to heat the matrix material in the supply system to the impregnation temperature. Likewise according to the invention, the matrix material is heated to an impregnation temperature in the direct supply system.The required impregnation temperature is a temperature at which the matrix material has sufficient flowability (i.e., low viscosity) for complete impregnation of the textile in the impregnation unit. The impregnation temperature is between 50 and 140 °C, preferably between 70 and 120 °C, preferably between 50 and 120 °C, preferably between 70 and 140 °C. For complete impregnation, the matrix material must saturate all areas of the textile with the matrix material. At the impregnation temperature, the matrix material has a viscosity of less than 1000 mPa*s, preferably less than 800 mPa*s, preferably less than 500 mPa*s, preferably less than 350 mPa*s, preferably less than 200 mPa*s, preferably less than 150 mPa*s, preferably less than 100 mPa*s, preferably less than 50 mPa*s.

[0014] In one embodiment, the matrix material can be further heated in the impregnation unit to cure the matrix material. In one embodiment, the impregnation temperature is selected such that the matrix material also cures. In this case, a particularly short supply line system must preferably be selected to prevent curing within the supply line system or to ensure that the impregnation temperature is only reached at the end of the supply line system (shortly before entering the impregnation unit).

[0015] In one embodiment, the supply system is a separate unit. This means that the supply system can be integrated into the impregnation system independently of the storage container or the impregnation unit and can also be controlled independently of the impregnation unit or the supply container during the process. In another embodiment, the supply system is part of the storage container and is not detachably connected to it.

[0016] Preferably, each of the direct supply systems has only a single heating device.

[0017] In one embodiment, the heating device is detachably in contact with the at least one direct supply system.

[0018] In the following, the at least one direct supply system will also be referred to simply as a supply system. However, it should be clear that one or more direct supply systems can be used both in the process for manufacturing the component and in the system for manufacturing the component.

[0019] In one embodiment of the method and in a plant for carrying it out, a storage container is used, from which a plurality of supply line systems lead to the impregnation unit, each supply line system having at least one of its own heating devices. In another embodiment of the method and the plant, a plurality of supply line systems and storage containers are used, each supply line system being connected to another storage container, but all supply line systems leading to a single impregnation unit and each supply line system having at least one of its own heating devices. Statements regarding the storage container should therefore be understood as also applying to the use of a plurality of storage containers in the method and / or the plant. If more than two storage containers are used in the method and / or the plant, these storage containers can be constructed identically or differently from one another.For example, a first reservoir may have a pressing device, whereas the second reservoir does not. However, when using multiple reservoirs, the matrix material is not transferred from a first reservoir to a second (or third) reservoir and then to the impregnation unit. Instead, the matrix material is always fed from the reservoir directly to the impregnation unit via the supply line.

[0020] For the description of this invention, the terms matrix and matrix material, resin and resin material are used synonymously. This refers to a thermosetting material for impregnating a textile made of reinforcing fibers, where the reinforcing fibers are particularly preferably carbon fibers and / or glass fibers. A textile is to be understood as a woven fabric, a UD fabric, a nonwoven material or a mixture of the aforementioned materials. The textile can also be a multiaxial fabric, a so-called non-crimp fabric (with or without nonwoven material). A pellet, even if it consists of fiber material, does not constitute a textile within the meaning of the invention. The term impregnation is to be understood as any type of component production in which a textile made of reinforcing fibers is transformed into a component by the addition of a matrix material (and optionally heat and pressure).A component is any part that, alone or together with other components, forms a final product.

[0021] If the term room temperature is used in the description, this should be understood to mean a temperature between 16 °C and 26 °C, preferably between 20 °C and 25 °C.

[0022] According to the invention, the matrix material in the storage container should not be heated at all. If the matrix material in the storage container is not heated at all, this means that the matrix material in the storage container is only at room temperature, but no additional heating takes place. The matrix material is therefore not frozen in the storage container. Advantageously, heating the matrix material to impregnation temperature is therefore possible faster and with less energy than would be the case when using frozen matrix material.

[0023] In one example of the proposed concept, during the entire impregnation process for producing the fiber-reinforced component, less than 30%, preferably less than 20%, preferably less than 10%, of the matrix material required for impregnation in the feed system (or in all feed systems combined) is heated simultaneously. It is understood that during the impregnation process, the entire matrix material must generally be heated for impregnation to occur. However, in the proposed process, only a small amount of the material in the feed system needs to be heated at any one time, while the majority of the matrix material remains unheated and therefore remains at room temperature in the storage container.

[0024] In one embodiment of the process, the thermosetting matrix material chosen for impregnation has a viscosity between 50,000 mPa*s and 120,000 mPa*s, preferably between 80,000 mPa*s and 100,000 mPa*s, at room temperature (16°C - 26°C). It is understood that the process can still be carried out when using a thermosetting matrix material with a different viscosity. Even if, for example, a matrix material that is non-flowable or barely flowable at room temperature is used, the matrix material can flow from the storage container into the supply system without heating the matrix material in the storage container. For this purpose, pressure can be exerted on the storage container, for example, so that the volume of the storage container is reduced and the non-flowable or barely flowable matrix material is also pressed into the supply system.In one embodiment of the idea, the supply system has a control unit by which the pressure, flow rate and / or temperature of the matrix material in the supply system is / can be measured and / or influenced during the process for manufacturing the component. This can advantageously ensure that the matrix material enters the impregnation unit at the correct impregnation temperature and / or the correct flow rate and / or the correct pressure, so that the quality of component production is reproducibly high. In a further embodiment, the supply system additionally has a degassing device, so that degassing is possible within the supply system. This can prevent gas bubbles (matrix-free areas) within the component, even if the matrix material in the storage container has not been degassed beforehand.However, the matrix material can also be degassed, whereby the process according to this idea allows the degassed state of the matrix material to be maintained until impregnation. Storage, heating, feeding, and impregnation thus take place without contact with gases or gas mixtures, such as air.

[0025] In a further embodiment of the concept, the supply system has at least one sieve that influences the pressure, viscosity, and / or flow rate of the matrix material. The at least one sieve is preferably located at the transition from the supply system to the impregnation unit. Depending on the mesh size and thickness of the wire mesh of the at least one sieve, the matrix material can only pass through the sieve if it has a corresponding viscosity at a given pressure. At the same time, the flow rate can also be influenced by the at least one sieve. Preferably, the at least one sieve is reversibly removable from the supply system. For example, the at least one sieve can be provided in the connecting piece or as part of the connecting piece of the supply system.Depending on the matrix material used and / or the desired component, the at least one sieve can be exchanged, allowing other process parameters to be easily adjusted or monitored. The sieve can preferably also be used additionally or alternatively to mix the matrix material in the feed system. For example, the feed system can have a plurality of sieves that perform different functions within the feed system (and therefore also have different mesh sizes and wire mesh thicknesses).

[0026] In an embodiment in which a plurality of supply systems are used, the supply systems can also transport different resin materials to the impregnation unit. Particularly if the component is to be impregnated with a multi-component matrix material, the supply system can transport the various components, which are then brought together in the impregnation unit or in an end region of the supply system shortly before the impregnation unit. For this purpose, the various components are stored in different storage containers, each of which is connected to the impregnation unit via its own direct supply system. In another embodiment, the supply system can have an access point through which additives for the matrix material can be introduced into the supply system.

[0027] In a further embodiment of the present concept, the volume of the storage container is reduced by a pressure device during the production of the fiber-reinforced component. During the volume reduction, the matrix material is preferably pressed from the storage container into the supply system, so that at the end of the process, little or no matrix material remains in the storage container. Preferably, the volume of the storage container is reduced reversibly, so that the storage container remains reusable after emptying and can be refilled with matrix material. In one embodiment of the concept, a storage container can also be used for the production of a plurality of components in a plurality of production processes (or production cycles) and can therefore contain a corresponding amount of matrix material.In each individual process for manufacturing a component, the volume of the storage container is reduced by a certain percentage of the previous volume of the storage container.

[0028] In one embodiment of the method, a vacuum unit or a positive pressure unit and / or a mechanical pressing unit is used as the pressure device for reducing the volume of the storage container. For example, a vacuum pump can be used to slowly evacuate the impregnation unit during the component manufacturing process. Furthermore, a squeezing device can be attached to the storage container, which reduces the volume of the storage container from the top toward the supply system during the component manufacturing process. In both cases, the matrix material is pressed or pulled from the storage container toward the supply system, whereby matrix material enters the supply system.

[0029] In one embodiment of the method, a heat exchanger is used as at least one heating device. The heat exchanger is preferably operated with waste heat from other processes. The heat exchanger can, for example, be provided in a spiral shape around the supply system or parts of the supply system and heat the tubes (or the only tube) of the supply system. The matrix material is located within the tubes of the supply system and is in direct contact with them. If a material with good thermal conductivity is used for the tubes, the heat from the tubes is transferred directly to the matrix material, so that heating can occur without direct contact between the heat source and the matrix material. The at least one heating device can of course also (additionally or alternatively) contain another heat source, such as infrared radiators or heating coils.A combination of different heating devices for heating the matrix material is also possible, wherein in one embodiment a stepwise increase of the heating temperature by the different heating devices is also possible.

[0030] The supply system is preferably not an extruder.

[0031] A further subject of the present idea concerns a supply system for a method as described above. Therefore, the statements made so far should also apply to the supply system—where appropriate. On the other hand, statements described below for the supply system should also apply to the method for component production using such a supply system.

[0032] The supply system for a process (as described above) should have a tubular structure with two—preferably opposing—end pieces. A first end piece can be reversibly or permanently connected to the impregnation unit, and a second end piece can be connected to the storage container. The supply system has at least one heating device that heats thermosetting matrix material at a temperature between 16°C and 26°C, preferably between 20°C and 25°C, from the storage container to an impregnation temperature, while the matrix material flows from the storage container to the impregnation unit through the supply system. The supply system preferably also has a control unit with which the temperature and / or flow rate of the heated thermosetting matrix material can be checked and / or changed before it enters the impregnation unit.The thermosetting matrix material is transported directly from the storage container to the impregnation unit via the supply line system, whereby the supply line system represents the shortest and preferably single pipe-like connection between the two components. When using a reversible connection of the end pieces, the supply line system can advantageously be used for different component manufacturing processes, similar to a coupling piece. Therefore, the end pieces are preferably either fixed in shape and size (standardized) or a plurality of end pieces are available, which can be selected depending on the storage container and / or impregnation unit used and / or required process parameters and reversibly mounted to the supply line system. In one embodiment, the supply line system is provided with an end piece fixed to the storage container and can be reversibly connected to the impregnation unit with an end piece.

[0033] In one embodiment, the supply line system has a length of less than 15 meters, less than 10 meters, less than 5 meters, less than 3 meters, less than 1.5 meters, or less than 1 meter. The length of the supply line system corresponds to the path length between the storage container and the impregnation unit.

[0034] In one embodiment, the supply system and storage container form a unit and cannot be separated from each other without destruction.

[0035] In one embodiment, the supply line system is formed from a single tubular connection, which represents the shortest connection between the storage container and the impregnation unit. In another embodiment, the supply line system is formed from a plurality of tubular connections, which run approximately parallel to one another and each form the shortest connection between the storage container and the impregnation unit. In one embodiment of the supply line system, the supply line system has at least one control unit, at least in the region of the first end piece. The control unit should preferably be able to check and / or change the temperature and / or flow properties of the heated matrix material before it enters the impregnation unit. For example, the control unit can have a thermocouple (e.g., a contact thermometer) that measures the temperature of the matrix material.If the control unit detects a temperature difference between a set target temperature and the actual temperature of the matrix material, the control unit can, for example, influence the at least one heating device and increase or decrease its temperature. The control unit can also include a device that measures the flow rate of the matrix material (e.g., a sieve element) and compares the actual and target values, possibly influencing the flow rate of the matrix material through the pressure device and the volume change of the storage container. Furthermore, the temperature measurement can serve as a safety monitor to detect and prevent unwanted curing reactions and overheating of the system at an early stage.

[0036] In one embodiment, the supply system comprises a heat exchanger as at least one heating device. In one embodiment, each supply system comprises only a single heating device, preferably a heat exchanger.

[0037] In one embodiment, the supply system comprises a material, at least in the contact area with the matrix material, that prevents or reduces the adhesion of the matrix material to the supply system. Preferably, the tubes for transporting the matrix material are made of this material. This advantageously allows for better processing of matrix material, even at room temperature.

[0038] A further subject of the present concept concerns a plant for the production of fiber-reinforced components. The previously described statements regarding the process shall apply to the plant with regard to the manufacturing process. Furthermore, the statements regarding the supply system shall apply to the plant. To the extent that statements regarding the plant concern aspects of the process or the supply system, these statements shall apply accordingly.

[0039] The plant shall comprise at least one impregnation unit for impregnating a textile made of reinforcing fibres, a storage container with thermosetting matrix material for impregnating the textile and a direct supply system with at least one heating device - as described above.

[0040] In one embodiment of the system, the storage container is a flexible bag. A bag is considered flexible if it can be compressed (preferably reversibly), meaning its volume can be reduced, for example, by squeezing the bag. In one embodiment of the bag, the bag is not only compressible but also expandable, allowing the volume of the bag to be increased within certain tolerance ranges without damaging the bag.

[0041] In one embodiment, the bag is made of a heat-resistant polymer material (for example, as a film bag) and has an outlet opening at one end with a connecting element for an end piece of the supply system. It is conceivable, for example, that the matrix material manufacturer sells and delivers the matrix material in a corresponding bag. For component production, the bag can be inserted into the storage container, or the bag itself represents the storage container. By using the bag as a storage container, the matrix material no longer needs to be degassed before component production. At the same time, a flexible bag allows for improved emptying (by reducing the volume of the bag), and mixing of the matrix material within the bag would also be possible.Preferably, the bag is provided in a resealable manner so that the bag can also be used to store matrix material for various manufacturing processes.

[0042] Preferably, the bag has a feed opening through which additives can be added to the matrix material in the bag - for example, special hardeners.

[0043] In one embodiment, a bag as a storage container together with a supply system forms a unit that cannot be separated from each other.

[0044] In one embodiment of the system, the system comprises a pressure device that can change—preferably reduce—the volume of the storage container (preferably a flexible bag). In one embodiment, the storage container (preferably a flexible bag) itself comprises the pressure device.

[0045] A further subject of the present invention relates to a storage container for the described method and the described system. The storage container is a flexible bag and has a mechanical pressure device for changing the volume (preferably for reducing the volume). Together with a supply system (as already described), the storage container in the form of a flexible bag forms a non-detachable unit. Statements regarding the method, the supply system, and the system also apply accordingly to the storage bag, and vice versa.

[0046] The idea is then described in more detail using two figures, whereby the figures only concern embodiments of the idea and are not to be understood as limiting.

[0047] Figure 1 shows a schematic diagram of a component manufacturing system with a direct feed system in which a flexible resin container is used as a storage container.

[0048] Figure 2 shows schematically another embodiment of the system from Figure 1, the difference being in the way the storage container is emptied.

[0049] Figure 1 shows a schematic representation of a system for producing a fiber-reinforced component. A textile to be impregnated is placed into the impregnation unit 1. A storage container 2 contains a matrix material through which the textile is to be impregnated and turned into the component. A direct feed system 3 is provided between the storage container 2 and the impregnation unit 1, whereby the matrix material from the storage container 2 passes directly (and thus without detours) through the feed system 3 into the impregnation unit 1. The feed system 3 has a heating device 4 designed as an in-line heater. The heating device 4 heats the matrix material from the storage container 2 to a temperature required for impregnation. In the storage container 2 itself, the matrix material is at room temperature. The matrix material is therefore heated only in the feed system 3 and only in portions.Consequently, only a small portion of the matrix material still present (and not yet reached the impregnation unit 1) is fully heated by the heating device 4 of the supply system 3, which then flows into the impregnation unit 1 and impregnates the textile. The matrix material is neither fully heated in the storage container 2, nor is part or all of the matrix material in the storage container 2 heated to a temperature corresponding to the impregnation temperature for the matrix material. According to the embodiment in Figure 1, the storage container 2 is a bag that can be processed by a pressure roller as a pressure device 6 during the manufacturing process. The pressure roller 6 can reduce the volume of the bag (by compressing the bag), so that the matrix material within the bag is pressed towards the supply system 3 and into the supply system 3.The supply system 3 according to Figure 1 also has a control unit 5, which is provided in the immediate vicinity of the impregnation unit 1. In this example, the control unit 5 has sensors that can measure the pressure, the volume flow and / or the temperature and / or other characteristics of the matrix material. The control unit 5 can also control the pressure device 6 and / or the heating device 4. For example, the control unit 5 can increase or decrease the temperature of the heating device 4 and move the pressure roller 6 toward or in the opposite direction of the supply system 3 and / or change (increase or decrease) the pressure on the storage container 2.

[0050] In the embodiment of Figure 2, a flexible resin container (for example, a bag 7) was inserted into the storage container 2. The impregnation unit and / or the supply system 3 can be evacuated during the manufacturing process of the component (i.e., the impregnation of the textile with the matrix material), so that the matrix material flows towards the supply system 3. In another embodiment, the storage container 2 can be pressurized with compressed air, so that the matrix material flows from the storage container 2 into the supply system 3. The matrix material only receives the temperature required for impregnation from the heating device 4 (in-line heating) within the supply system 3. The matrix material within the supply system 3 is then completely heated to the impregnation temperature.Consequently, only a small portion of the remaining matrix material (the matrix material that is not yet in the impregnation unit) in the supply line system 3 is heated to impregnation temperature. This type of heating is more energy-efficient and also beneficial for the matrix material. Unneeded matrix material in the storage container 2 was not heated, meaning that no relevant crosslinking reactions took place in the matrix material. This means that the unneeded matrix material can be used for other processes and does not have to be disposed of (because it is already too strongly crosslinked). Furthermore, even highly reactive matrix material systems can be used without an overly slow impregnation process leading to undesirable crosslinking of the matrix material in the storage container 2 or a supply line.Advantageously, with the proposed system and method, the matrix material is only brought to the impregnation temperature immediately before impregnation, so that crosslinking reactions can be significantly reduced or completely eliminated beforehand. In the impregnation unit 1, the textile impregnated with the matrix material can be further warmed or heated if necessary to ensure complete crosslinking and / or curing of the matrix material for component production. Furthermore, the impregnation unit 1 can also be designed to maintain the temperature of the matrix material in the impregnation unit 1 until the textile is completely impregnated. The impregnation unit 1 can also be pressurized for component production.

Claims

Process for component production with heating device in the supply system Claims:

1. A method for producing a fiber-reinforced component with a thermosetting matrix material, wherein for producing the fiber-reinforced component, a textile made of reinforcing fibers is processed with a thermosetting matrix material in a matrix impregnation step, wherein the thermosetting matrix material required for the impregnation is stored in a storage container (2) and the textile made of reinforcing fibers is stored in an impregnation unit (1), wherein at least one direct supply system (3) is provided between the storage container (2) and the impregnation unit (1), wherein the thermosetting matrix material passes from the storage container (2) directly into the impregnation unit (1) through the at least one direct supply system (3), characterized in thatthat each of the at least one direct supply system (3) has at least one heating device (4) and in the process for producing the fiber-reinforced component, the thermosetting matrix material is heated exclusively in the at least one direct supply system (3) by the at least one heating device (4) to a temperature required for the impregnation of the textile made of reinforcing fibers with the thermosetting matrix material and wherein the thermosetting matrix material is present in the storage container (2) at room temperature between 16 °C and 26 °C in the process.

2. The method according to claim 1, wherein during the entire impregnation process for producing the fiber-reinforced component, less than 30% of the total thermosetting matrix material in the at least one direct feed system (3) is heated simultaneously.

3. Process according to at least one of the preceding claims, wherein the viscosity of the thermosetting matrix material at room temperature between 16 °C and 26 °C is between 50,000 mPa*s and 120,000 mPa*s.

4. Method according to at least one of the preceding claims, wherein in at least one direct supply system (3) the pressure, the flow rate and / or the temperature of the thermosetting matrix material is / are measured and / or influenced via a control unit (5) of the at least one direct supply system (3).

5. The method according to claim 4, wherein at least one screen within the at least one direct supply system (3) influences the pressure and / or the flow rate of the thermosetting matrix material.

6. Method according to at least one of the preceding claims, wherein the volume of the storage container (2) is reduced by a pressure device (6) during the production of the fiber-reinforced component.

7. The method according to claim 6, wherein a vacuum unit or overpressure unit and / or a mechanical pressing unit is used as the pressure device (6).

8. Method according to at least one of the preceding claims, wherein a heat exchanger is used as at least one heating device (4).

9. Supply system (3) for a method according to claims 1 to 8, wherein the supply system (3) has a tubular structure with two end pieces, wherein a first end piece is connectable to an impregnation unit (1) and a second end piece is connectable to a storage container (2), characterized in that the supply system (3) has at least one heating device (4) which heats thermosetting matrix material with a temperature between 16°C and 26°C from the storage container (2) to an impregnation temperature while the thermosetting matrix material flows directly from the storage container (2) to the impregnation unit (1) through the supply system (3), wherein the supply system (3) has a control unit (5) with which the temperature and / or the flow properties of the heated thermosetting matrix material can be checked and / or changed before the transfer to the impregnation unit (1).

10. Supply system (3) according to claim 9, wherein the supply system (3) consists of a single tube.

11. Supply system (3) according to at least one of claims 9 to 10, wherein the supply system (3) has a heat exchanger as at least one heating device (4).

12. Plant for the production of fiber-reinforced components according to a method according to at least one of claims 1 to 8, wherein the plant comprises at least one impregnation unit (1) for the impregnation of a textile made of reinforcing fibers, a storage container (2) for receiving thermosetting matrix material for impregnating the textile and a direct supply system (3) according to at least one of claims 9 to 11 with at least one heating device (4).

13. System according to claim 12, wherein the storage container (2) is a flexible bag (7).

14. Plant according to claim 12 or 13, wherein the storage container has a mechanical pressing device for reducing the volume of the storage container.

15. Storage container for a method according to claim 1, wherein the The storage container is a flexible bag and has a mechanical pressing device for changing the volume and forms a component unit with a supply system with a heating device.

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