Resin permeability measuring device for composite material preform

Abstract

The utility model discloses a device for measuring the resin permeability of a composite material preform, and relates to the technical field of composite material production auxiliary equipment. The measuring device comprises a vacuum bag used for accommodating a plurality of preforms arranged at intervals; the flow guide net is arranged at the first ends of the plurality of prefabricated bodies and is used for guiding the flow of the resin; the resin conveying tank is located at the first end of the prefabricated body, connected with the flow guide net through a first guide pipe and used for conveying resin to the flow guide net; the resin collecting tank is located at the second end of the prefabricated body, connected with the second end of the prefabricated body through a second guide pipe and used for receiving the resin flowing out of the prefabricated body; the vacuum pump is connected with the resin collecting tank and is used for providing vacuum suction force, so that the resin flows to the second end from the first end of the prefabricated body; a pressure gauge is arranged on the second guide pipe and used for measuring the pressure value of the resin outlet end. The measuring device provided by the utility model can effectively measure the permeability of the resin at any time point of the preform during pouring.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of composite material production auxiliary equipment, and in particular to a composite material preform resin permeability measuring device. BACKGROUND

[0002] The liquid forming technology of composite materials is a low-cost advanced composite material forming process technology, in which liquid resin is injected into a closed mold cavity filled with fiber preforms under pressure, and the liquid resin is infiltrated into the preform while flowing to fill the mold and is cured to form a product.

[0003] The control of the resin infiltration process is the key to the liquid forming technology. The process is a complex process of resin permeation and flow in the fiber preform, and there are many factors affecting the flow process. If not properly controlled, some forming defects such as dry spots and voids may occur. Therefore, it is necessary to accurately determine the permeability of the resin in the preform. CONTENT OF THE UTILITY MODEL

[0004] To solve the above technical problems, the application provides a liquid forming composite material preform resin permeability measuring device, which can effectively determine the permeability of the resin in the preform at any time point during pouring.

[0005] The application provides a composite material preform resin permeability measuring device, which comprises:

[0006] A vacuum bag is used to accommodate a plurality of preforms arranged at intervals.

[0007] A flow guide net is arranged at the first end of the plurality of preforms and used for guiding the flow of resin.

[0008] A resin delivery tank is located at the first end of the preform, connected to the flow guide net through a first conduit, and used for delivering resin to the flow guide net.

[0009] A resin collection tank is located at the second end of the preform, connected to the second end of the preform through a second conduit, and used for receiving the resin flowing out of the preform.

[0010] A vacuum pump is connected to the resin collection tank and used for providing a vacuum suction force to make the resin flow from the first end to the second end of the preform.

[0011] A pressure gauge is arranged on the second conduit and used for measuring the pressure value of the resin outlet end.

[0012] In some embodiments of the application, a scale line is arranged on the vacuum bag, and the initial position of the scale line is flush with the first end of the preform.

[0013] In some embodiments of the present application, the first conduit is provided with a resin inlet valve for controlling the input flow of the resin.

[0014] In some embodiments of the present application, the second conduit is provided with a resin outlet valve for controlling the output flow of the resin.

[0015] In some embodiments of the present application, the flow guide net is covered on the preform, and one end of the flow guide net away from the resin delivery tank has a preset distance from the first end of the preform.

[0016] In some embodiments of the present application, the preset distance is 15-25mm.

[0017] In some embodiments of the present application, the composite preform resin permeability measuring device further comprises:

[0018] A camera is arranged above the vacuum bag for recording the value of the resin flowing through the scale line in a preset permeation time, so as to obtain the resin permeation distance.

[0019] In some embodiments of the present application, the vacuum bag is provided with a sealant.

[0020] In some embodiments of the present application, the measuring device further comprises a first flow guide pipe, which is connected to the outlet end of the first conduit, and is arranged at the first end of the preform, and is arranged in a horizontal direction and has a length direction perpendicular to the length direction of the preform, and a plurality of first flow guide holes for delivering resin to the flow guide net are arranged on the first flow guide pipe along the length direction of the first flow guide pipe.

[0021] In some embodiments of the present application, the measuring device further comprises a second flow guide pipe, which is connected to the inlet end of the second conduit, and is arranged at the second end of the preform, and is arranged in a horizontal direction and has a length direction perpendicular to the length direction of the preform, and a plurality of second flow guide holes for receiving the resin flowing out of the preform are arranged on the second flow guide pipe along the length direction of the second flow guide pipe.

[0022] The technical scheme provided by the present application can have the following beneficial effects:

[0023] The present application provides vacuum suction by a vacuum pump, so that the resin flows from the first end to the second end of the preform, thereby the penetration distance of the resin in the preform at any time point can be determined; the pressure value at the resin outlet end is measured by a pressure gauge, so as to obtain the pressure difference between the resin inlet end and the resin outlet end; according to the pressure difference, the penetration distance and the penetration time, the penetration rate of the resin in the composite preform at any time point in the penetration process can be accurately determined.

[0024] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory and are not restrictive of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings incorporated in and forming a part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the application.

[0026] Figure 1 is a structural schematic diagram of a composite preform resin penetration rate measuring device according to an exemplary embodiment.

[0027] REFERENCE NUMERALS

[0028] 1, vacuum bag; 11, first end; 12, second end; 13, scale line; 2, flow guide net; 3, resin delivery tank; 31, first conduit; 32, resin inlet valve; 4, resin collection tank; 41, second conduit; 42, resin outlet valve; 43, pressure gauge; 5, vacuum pump; 6, camera; 7, first flow guide pipe; 8, second flow guide pipe; 10, preform. DETAILED DESCRIPTION

[0029] To make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other at will.

[0030] The application provides a composite material prepreg resin permeability measuring device, comprising a vacuum bag, a flow guide net, a resin conveying tank, a resin collecting tank and a vacuum pump, the vacuum bag is used for containing a plurality of interval arranged preforms; the flow guide net is arranged at the first end of the plurality of preforms and is used for guiding the resin; the resin conveying tank is located at the first end of the preform and is connected with the flow guide net through a first conduit and is used for conveying the resin to the flow guide net; the resin collecting tank is located at the second end of the preform and is connected with the second end of the preform through a second conduit and is used for receiving the resin flowing out of the preform; the vacuum pump is connected with the resin collecting tank and is used for providing a vacuum suction force to make the resin flow from the first end to the second end of the preform; a pressure gauge is arranged on the second conduit and is used for measuring the pressure value of the resin outlet end. The vacuum suction force provided by the vacuum pump makes the resin flow from the first end to the second end of the preform, so that the permeation distance of the resin in the preform at any time point can be determined; the pressure value of the resin outlet end is measured by the pressure gauge to obtain the pressure difference between the resin inlet end and the resin outlet end; according to the pressure difference, the permeation distance and the permeation time, the permeability of the resin in the composite material prepreg permeation process at any time point can be accurately determined.

[0031] Some specific embodiments described below aim to facilitate the understanding of the present embodiments by those skilled in the art, and the present embodiments are not limited to some specific embodiments described below.

[0032] As shown in Figure 1 An exemplary embodiment of the application provides a composite material prepreg resin permeability measuring device, comprising a vacuum bag 1, a flow guide net 2, a resin conveying tank 3, a resin collecting tank 4 and a vacuum pump 5, the vacuum bag 1 is used for containing a plurality of interval arranged preforms 10; the flow guide net 2 is arranged at the first end 11 of the plurality of preforms 10 and is used for guiding the resin; the resin conveying tank 3 is located at the first end 11 of the preform 10 and is connected with the flow guide net 2 through a first conduit 31 and is used for conveying the resin to the flow guide net 2; the resin collecting tank 4 is located at the second end 12 of the preform 10 and is connected with the second end 12 of the preform 10 through a second conduit 41 and is used for receiving the resin flowing out of the preform 10; the vacuum pump 5 is connected with the resin collecting tank 4 and is used for providing a vacuum suction force to make the resin flow from the first end 11 to the second end 12 of the preform 10; a pressure gauge 43 is arranged on the second conduit 41 and is used for measuring the pressure value of the resin outlet end.

[0033] In the embodiment, the resin is made to flow from the first end 11 to the second end 12 of the preform 10 by providing a vacuum suction force by the vacuum pump 5, so that the penetration distance of the resin in the preform 10 at any time point can be determined; the pressure value at the resin outlet end is measured by the pressure gauge 43 to obtain the pressure difference between the resin inlet end and the resin outlet end; according to the pressure difference, the penetration distance and the penetration time, the permeability of the resin in the composite preform 10 at any time point during the penetration process can be accurately determined. In addition, the resin permeability of multiple preforms 10 can be measured at the same time in the embodiment to reduce measurement error and improve the accuracy of the measurement results. The number of preforms 10 can be adjusted according to the measurement requirements, for example Figure 1 In the embodiment, the number of preforms 10 is five.

[0034] In an embodiment, the vacuum bag 1 is provided with a scale line 13, and the initial position of the scale line 13 is flush with the first end 11 of the preform 10.

[0035] In the embodiment, the scale line 13 is provided on the vacuum bag 1, and the initial position of the scale line 13 is flush with the first end 11 of the preform 10, which facilitates data reading.

[0036] In an embodiment, the first conduit 31 is provided with a resin inlet valve 32 for controlling the input flow of the resin.

[0037] In the embodiment, the resin inlet valve 32 is provided on the first conduit 31 to facilitate the control of the input flow of the resin.

[0038] In an embodiment, the second conduit 41 is provided with a resin outlet valve 42 for controlling the output flow of the resin.

[0039] In the embodiment, the resin outlet valve 42 is provided on the second conduit 41 to facilitate the control of the output flow of the resin.

[0040] In an embodiment, the flow guide net 2 covers the preform 10, and the end of the flow guide net 2 away from the resin delivery tank 3 has a preset distance from the first end 11 of the preform 10.

[0041] In the embodiment, the end of the flow guide net 2 away from the resin delivery tank 3 has a preset distance from the first end 11 of the preform 10, so that the flow guide net 2 can completely cover the first end 11 of the preform 10 to facilitate the flow of the resin from the first end 11 of the preform 10.

[0042] In an embodiment, the preset distance is 15-25 mm.

[0043] In the embodiment, the preset distance can be 15 mm, 20 mm or 25 mm.

[0044] In an embodiment, the resin permeability measuring device for the composite material preform 10 further comprises a camera 6 arranged above the vacuum bag 1, the camera 6 being used to record the resin flow value through the scale line 13 at a preset permeation time, so as to obtain the resin permeation distance.

[0045] In the embodiment, the permeation process of the resin is recorded by the camera 6, so as to facilitate data recording and statistics and improve work efficiency.

[0046] In an embodiment, the vacuum bag 1 is provided with a sealing glue.

[0047] In the embodiment, the vacuum bag 1 can be sealed by the sealing glue, so as to flow in the preform 10 under the action of the resin vacuum suction. The sealing glue can be arranged around the vacuum bag 1.

[0048] In an embodiment, the measuring device further comprises a first flow guide pipe 7, the first flow guide pipe 7 being connected with the outlet end of the first conduit 31, the first flow guide pipe 7 being arranged at the first end 11 of the preform 10, the first flow guide pipe 7 being arranged in a horizontal direction and the length direction of the first flow guide pipe 7 being perpendicular to the length direction of the preform 10, and a plurality of first flow guide holes for conveying the resin to the flow guide net 2 being arranged on the first flow guide pipe 7 along the length direction of the first flow guide pipe 7.

[0049] In the embodiment, the resin conveyed by the first conduit 31 can be drained to the first end 11 of each preform 10 by arranging the first flow guide pipe 7, so as to simultaneously measure the resin permeability of the plurality of preforms 10.

[0050] In an embodiment, the measuring device further comprises a second flow guide pipe 8, the second flow guide pipe 8 being connected with the inlet end of the second conduit 41, the second flow guide pipe 8 being arranged at the second end 12 of the preform 10, the second flow guide pipe 8 being arranged in a horizontal direction and the length direction of the second flow guide pipe 8 being perpendicular to the length direction of the preform 10, and a plurality of second flow guide holes for receiving the resin flowing out of the plurality of preforms 10 being arranged on the second flow guide pipe 8 along the length direction of the second flow guide pipe 8.

[0051] In the embodiment, the resin flowing out of the plurality of preforms 10 can be drained into the second conduit 41 by arranging the second flow guide pipe 8 at the second end 12 of the preform 10, so as to improve the resin collection efficiency.

[0052] An exemplary embodiment of the present application provides a measuring method for resin permeability of a composite material preform, mainly deriving a resin permeability formula according to Darcy's law and performing a resin infusion preform experiment. The derivation process of the resin permeability is as follows:

[0053] According to Darcy's law, it is obtained that

[0054]

[0055] In formula (1), x is the resin penetration distance; t is the penetration time; p is the pressure difference between the resin inlet and the resin outlet; K is the permeation rate; and η is the viscosity of the fluid.

[0056] Considering the one-dimensional flow characteristics, there is:

[0057]

[0058] Substituting formula (1) into formula (2), and after rearrangement, there is:

[0059]

[0060] Integrating both sides of formula (3), there is:

[0061]

[0062] The final integration result is:

[0063]

[0064] According to formula (5), the resin permeation rate is related to the penetration distance of the resin in the composite material preform, the penetration time, and the pressure difference between the resin inlet and the outlet. Therefore, the composite material preform resin permeation rate measuring device is designed, the penetration distance of the resin in the composite material preform, the penetration time, and the pressure difference between the resin inlet and the outlet are monitored in the resin infusion monitoring experiment, and the resin permeation rate of the composite material preform is calculated according to formula (5).

[0065] In order to more clearly explain the technical solutions of the present application, specific embodiments of the composite material preform resin permeation rate measuring method are listed.

[0066] Embodiment 1: The composite material preform resin permeation rate measuring method comprises the following steps:

[0067] (1) Five layers of 200mm×40mm×1.2mm carbon fiber unidirectional cloth are hot-pressed by a hot press at a pressure of 1.1MPa for 60s to prepare a preform resin permeation rate measuring sample.

[0068] (2) The prepared five 200mm×40mm×1mm preforms are placed in the center of the bottom plate of the vacuum bag in an orderly manner, and each preform is spaced 40mm apart.

[0069] (3) A flow guide net with a length of 320mm and a width of 40mm is placed on the five preforms and exceeds the preforms by 20mm (i.e., the preset distance is 20mm). After connecting the components according to the composite material preform resin permeation rate measuring device, the vacuum bag is tightly sealed with high-temperature sealant.

[0070] (4) Open the vacuum pump, resin inlet valve, resin outlet valve and camera. After the five preforms are filled with resin (i.e. the resin flows from the first end to the second end of the preform), close the devices.

[0071] (5) Watch the video taken by the camera. During the resin infiltration process, record the data of the infiltration distance x and the infiltration time t every 20 mm. For one preform, record ten points of the infiltration distance and time. Read the data of the five preforms and the pressure value on the second conduit.

[0072] (6) Calculate the resin infiltration rate of the preform according to formula (5).

[0073] In the table 1, the infiltration distance, the infiltration time and the infiltration rate of the resin in the preform are shown.

[0074] Table 1: Resin infiltration rate data table of the preform in the example

[0075] Penetration distance / mm Penetration time / s Permeability / m 2 ]] 0 0 0 20 50 13.33 40 722.3 3.69 60 881.3 6.80 80 1167.5 9.14 100 1358.3 12.27 120 1676.3 14.31 140 1894.4 17.24 160 2069.3 20.61 180 2296.4 23.51 200 2689.4 24.78

[0076] According to the data in the table 1, it can be seen that the method of the example 1 of the present application can accurately determine the resin infiltration rate at any point during the resin infiltration process in the composite material preform.

[0077] Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the aspects disclosed herein. The specification and examples given are exemplary only and the true scope and spirit of the application are indicated by the claims. The true scope and spirit of the application are indicated by the claims.

[0078] It should be understood that the application is not limited to the precise construction that has been described above and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is indicated by the appended claims, rather than the description.

Claims

1. A composite preform resin permeability measurement apparatus, characterized by, The application relates to a composite material prepreg resin permeability measuring device. The device comprises: a vacuum bag for containing a plurality of spaced prepregs; a flow guide net arranged at the first end of the plurality of prepregs for guiding resin flow; a resin conveying tank located at the first end of the prepregs and connected with the flow guide net through a first conduit for conveying resin to the flow guide net; a resin collecting tank located at the second end of the prepregs and connected with the second end of the prepregs through a second conduit for receiving resin flowing out of the prepregs; a vacuum pump connected with the resin collecting tank for providing vacuum suction force to make the resin flow from the first end to the second end of the prepregs; 2. The composite preform resin permeability measurement apparatus of claim 1, wherein, a pressure gauge arranged on the second conduit for measuring the pressure value of the resin outlet end.

3. The composite preform resin permeability measurement apparatus of claim 1, wherein, The vacuum bag is provided with a scale line, and the initial position of the scale line is flush with the first end of the prepregs.

4. The composite preform resin permeability measurement apparatus of claim 1, wherein, The first conduit is provided with a resin inlet valve for controlling the input flow of the resin.

5. The composite preform resin permeability measurement apparatus of claim 1, wherein, The second conduit is provided with a resin outlet valve for controlling the output flow of the resin.

6. The composite preform resin permeability measurement apparatus of claim 5, wherein, The flow guide net covers the prepregs, and the end of the flow guide net away from the resin conveying tank has a preset distance from the first end of the prepregs.

7. The composite preform resin permeability measurement apparatus of claim 2, wherein, The preset distance is 15-25 mm. The composite material prepreg resin permeability measuring device further comprises:

8. The composite preform resin permeability measurement apparatus of claim 1, wherein, a camera arranged above the vacuum bag for recording the value of the resin flowing through the scale line in a preset permeation time to obtain the resin permeation distance.

9. The composite preform resin permeability measurement apparatus of claim 1, wherein, The vacuum bag is provided with sealing glue.

10. The composite preform resin permeability measurement apparatus of claim 1, wherein, The measuring device further comprises a first flow guide pipe connected with the outlet end of the first conduit, the first flow guide pipe is arranged at the first end of the prepregs, the first flow guide pipe is arranged in the horizontal direction, the length direction of the first flow guide pipe is perpendicular to the length direction of the prepregs, a plurality of first flow guide holes for conveying resin to the flow guide net are arranged on the first flow guide pipe along the length direction of the first flow guide pipe. The measuring device further comprises a second flow guide pipe connected with the inlet end of the second conduit, the second flow guide pipe is arranged at the second end of the prepregs, the second flow guide pipe is arranged in the horizontal direction, the length direction of the second flow guide pipe is perpendicular to the length direction of the prepregs, a plurality of second flow guide holes for receiving resin flowing out of the plurality of prepregs are arranged on the second flow guide pipe along the length direction of the second flow guide pipe.

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