CN113844059B

CN113844059B - Method for manufacturing fiber reinforced plastic pipe section module and pipe section module

Info

Publication number: CN113844059B
Application number: CN202111196103.6A
Authority: CN
Inventors: 罗庆君; 张建庭
Original assignee: Hebei Hengrui Composite Material Co ltd
Current assignee: Hebei Hengrui Composite Material Co ltd
Priority date: 2021-10-14
Filing date: 2021-10-14
Publication date: 2023-08-22
Anticipated expiration: 2041-10-14
Also published as: CN113844059A

Abstract

The present disclosure provides a method of manufacturing a fiber reinforced plastic pipe section module, the pipe section module comprising at least a first surface and a second surface, and a first end region and a second end region arranged at both axial ends of the pipe section module, the manufacturing method employing a vacuum infusion molding method, characterized in that a mold device is provided for: a master mold providing a first surface configuration; a first secondary die and a second secondary die providing a configuration of the second surface of the second end region; wherein the primary mould provides a corrugated configuration arranged substantially parallel between the front end region and the rear end region of the pipe section mould, and the shaping surface of the first secondary mould is provided with at least one ridge configuration, and the shaping surface of the second secondary mould is provided with at least one groove configuration, the vacuum forming pockets being arranged such that the primary mould, the first secondary mould, the second secondary mould, together with the vacuum forming pockets, constitute a vacuum infusion chamber in common communication. The present disclosure also provides a pipe segment module.

Description

Method for manufacturing fiber reinforced plastic pipe section module and pipe section module

Technical Field

The present disclosure relates to the application of fiber reinforced plastic articles to the field of pipe laying and pipe joining, and in particular to the formation of such articles using a vacuum infusion process.

Background

Pipes have many applications. Taking domestic culvert passages as an example, reinforced concrete structures are generally adopted, but the reinforced concrete structures have the technical problems of long production period, high transportation cost, long construction period, shorter service life, more potential safety hazards and the like.

The composite material for preparing the pipeline has the remarkable advantage in the aspect of corrosion resistance. The winding process to make glass fiber reinforced plastic pipes is a well known pipe application.

The same applicant of the present application has developed a technique for applying SMC composites to culverts, ducts, which provides, in addition to remarkable anti-corrosive properties, mechanical properties with competitive advantages, high strength and low deformability. See patent document 1 and patent document 2 below for details.

Patent document 1

Patent application number CN202020468924.5, publication number 2021, 2, 9U, publication number CN212505912U, patent name "culvert member, culvert assembly, culvert member, culvert assembly, and culvert" filed by the same applicant of the present application. This patent application discloses a culvert pipe member integrally made of SMC composite material by a molding process. The application also teaches a stent assembly, a stent member, a stent assembly and a stent.

Patent document 2

Patent application, publication (bulletin) number filed by the same applicant as the present application: CN112984232a, application number: CN202110438627.5, filing date: 2021-04-22 entitled "piping assembly and piping assembly method", discloses a piping assembly comprising: the first pipe section at least comprises a small diameter end, the second pipe section at least comprises a large diameter end and a spacing device, wherein at least the second pipe section is composed of a plurality of pipe section modules, lateral connecting mechanisms are arranged on two sides of the pipe section modules, the lateral connecting mechanisms are arranged along the longitudinal direction or the axial direction of the pipe section, and when the pipe section modules are assembled, the plurality of pipe section modules of the second pipe section cover the small diameter end of the first pipe section at the large diameter end.

The SMC composite material molding process has satisfactory application effect when applied to preparing pipe fittings. However, the molding process has its own limitations, namely, the cost of the disposable mold is high, and the molding process is particularly remarkable in the production of large-sized products.

The inventors have instead developed a vacuum infusion process, also known as a vacuum infusion process. The vacuum infusion process is divided into a dual mode vacuum infusion process and a vacuum bagging process. The patent documents cited below relate to vacuum bagging processes.

Patent document 3

Publication No. CN106881881B, entitled "method for vacuum introducing and processing weather-resistant glass fiber reinforced plastic product", application No. CN201710198055.1, applicant, chongqing Hai Qing New Material Co., ltd. The invention provides a vacuum importing processing method of a weather-proof glass fiber reinforced plastic product, which comprises the following steps: preparing a mould, spraying a gel coat layer, paving at least 3 layers of glass fibers, paving a porous isolating film, paving a honeycomb duct, paving a guide net, paving a vacuum bag, vacuumizing, introducing resin and demoulding; the laying sequence of the diversion pipe and the diversion net in the traditional vacuum leading-in processing method is changed, and the inner surface of the manufactured glass fiber reinforced plastic product has no pipe pressure mark.

The above documents are incorporated herein by reference in their entirety.

Disclosure of Invention

[ problem to be solved ]

It is an object of the present disclosure to provide a solution which is particularly suitable for improving the production, connection, sealing, laying of large-bore pipes. In particular, the product of the present disclosure is a unit module for fabricating a fabricated pipe by using a vacuum infusion method, and the unit module may be applied to a fabricated tank.

However, vacuum infusion processes are generally well suited to use with a mold in combination with a vacuum bag, the molding surface being provided by the molding surface of the mold, the other surface being covered by the vacuum bag, essentially following the thickness of the laid fiber, and not easily forming a clear and distinct individual configuration.

However, in the target product required by the present disclosure, a special assembly mechanism needs to be implemented, for example, 2-3 modules are assembled circumferentially to form a pipe section, an adhesive tape groove is required to be provided on the outer peripheral surface of the first end, and when another pipe section is used to wrap the outer peripheral surface, a special socket structure is implemented to implement connection and sealing between two pipe sections. In addition, it is desirable to provide further reinforcement on the outer peripheral surface of the second end portion and to increase flexibility and adaptability of the product for assembly and application. However, the vacuum introduction process must be modified to accommodate the requirements of the present product.

Technical scheme

To solve the above technical problems and achieve the object of the present disclosure, the present disclosure provides solutions in the following respects.

In one aspect of the present disclosure, there is provided a method of manufacturing a pipe section module made of a fiber reinforced plastic, the pipe section module including at least a first surface and a second surface, and a first end region and a second end region disposed at both axial ends of the pipe section module, two or more pipe section modules being arranged in the same axial direction and being connected in the circumferential direction to obtain a pipe section closed in the circumferential direction, the manufacturing method using a vacuum infusion molding method, characterized in that a mold device is provided for: a master mold providing the first surface configuration; a first secondary mold providing a configuration of the second surface of the first end region; a second secondary mold providing a configuration of a second surface of the second end region; wherein the main mould provides a corrugated configuration arranged substantially parallel between the front end region and the rear end region of the pipe section module, the corrugated configuration being constituted by an alternating arrangement of elongated recesses and elongated protrusions in the axial direction, and the shaping surface of the first auxiliary mould is provided with at least one ridge configuration for forming a glue strip groove on the outer surface of the first end region of the pipe section module, the glue strip groove extending substantially in the circumferential direction, and the shaping surface of the second auxiliary mould is provided with at least one groove configuration extending substantially in the circumferential direction for forming a stiffening rib on the outer surface of the second end region of the pipe section module, the main mould and the first and second auxiliary moulds being fixed to each other in a removable manner, and a vacuum forming pocket being arranged such that the main mould, the first auxiliary mould, the second auxiliary mould, together with the vacuum forming pocket, constitute a vacuum filling chamber in common communication.

Further, a configuration in which a front end portion inner flange structure is further provided on the first auxiliary die, and a configuration in which a rear end portion outer flange structure is further provided on the second auxiliary die are preferable.

Preferably, the reinforcement rib at the second end can also be provided as an outer flange. The inner flange and the outer flange provide a particularly cost effective reinforcement structure in the present product, since the outermost outer end of the pipe section is also the most vulnerable area, requiring a particular reinforcement. The design and arrangement of the die in the process are easy to realize the structural design requirement. Furthermore, the design of the inner flange of the first end part and the outer flange of the second end part also skillfully avoids the interference of the assembly pipe section of the die and the socket connection of the pipe section special to the technical scheme, and is simple and optimized in process design.

Further, the process improvement of the present disclosure, a plurality of functional layers and a fiber layer are also laid on the master mold, the fiber layer being arranged to: paving a layer of chopped glass fiber mat on the whole molding surface of the main die from the molding surface close to the main die; at least two layers of fiber woven fabrics are paved on the whole molding surface of the main mold close to the chopped glass fiber mat, wherein the fiber woven fabrics of the same layer form joints in a butt joint mode, the joints of the fiber woven fabrics of the same layer are approximately orthogonal to the joints of the fiber woven fabrics of the adjacent layers, and the joints of the fiber woven fabrics of the separated layers are approximately parallel and staggered; and arranging fibers on molding surfaces of the first auxiliary mold and the second auxiliary mold respectively as follows: and arranging at least one layer of fiber woven cloth close to the auxiliary molding surface, and then arranging continuous glass fiber bundles extending along the circumferential direction to fill up the grooves on the auxiliary molding surface.

Further, at least two layers of fiber woven fabrics paved on the whole molding surface of the main mold are arranged to be circumferentially paved with one layer of circumferential thick fabric, the adjacent layer is arranged to be axially paved with one layer of axial thin fabric, the gram weight of the circumferential thick fabric is larger than that of the axial thin fabric, and the fiber woven fabrics are paved in the circumferential direction and the fiber woven fabrics are paved in the axial direction alternately.

In a further aspect, it is preferable that 6 to 14 layers of fiber woven cloth are laid on the entire molding surface of the main mold. More preferably, in the present product, 8 layers of fiber woven cloth are laid on the entire molding surface of the master mold.

The above solution, firstly fully considering the optimization of the laying of the fiber layer based on the master mould, and the emphasis is that the circumferential laying and the axial laying are alternately performed, and the fiber woven fabric laid in the circumferential direction is larger than the fiber woven fabric laid in the axial direction, so that the laying operation is obviously biased to the circumferential strength of the module, namely, considering the circumferential strength of the product body assembled into the pipe section and the tank body, further, the circumferential laying and the axial laying are alternately performed, the joint area of each layer is approximately orthogonal, the insufficient strength of the joint is effectively dispersed, and further, the separated layers are simultaneously laid in the axial direction or are simultaneously laid in the circumferential direction, for example, the laying of the non-whole cloth can be placed at different positions, thereby further staggering the joints of the phase-separated layers. Thus, the laying of the multi-layered fiber cloth, even if the butt joint type seam is adopted, maximally limits the scattered seam and the staggered seam, and the seam orientation is crossed, thereby improving the fiber reinforcement effect.

In addition, the arrangement of the auxiliary mould, besides providing a local outer surface configuration, also provides a substrate for independently laying a fiber layer, in the scheme of the disclosure, the auxiliary mould is independently laid with a very thin fiber woven cloth, then is laid with surrounding fiber bundles, the fiber bundles are more easily oriented and extruded into grooves arranged on the shaping surface of the auxiliary mould to form continuous fiber bundles arranged along the circumferential direction, and the continuous fiber bundles are additionally wrapped by the fiber cloth, so that the protruding reinforcing effect can be given to two end regions of the pipe section module after the product is shaped, and the laying mode can be more economical and can maximize the compressive strength of ribs filled by the continuous fiber bundles in the circumferential direction of a pipeline.

The continuous glass fibers mentioned above refer to longer glass fibers. The drawing process forms continuous glass fibers, which are typically wound in a drawing machine for several tens of minutes during production. The technical term as opposed to continuous glass fibers is "chopped glass fibers", i.e. continuous glass fibers are cut into short fibers, e.g. a few centimeters long. The continuous fibers may be woven into a fibrous cloth. In the above, the woven fiber cloth is laid on the molding surface of the auxiliary mold, and then the continuous fiber bundles are laid in the groove configuration of the auxiliary mold, so that the woven fiber cloth provides the wrapping effect for the continuous fiber bundles after the product is molded. The continuous fiber bundles more easily fill the grooves in place. In the fiber laying of the auxiliary mold, a continuous fiber bundle is used in combination with a fiber woven cloth.

In the operation of the present disclosure, a guide net is disposed on the molding surface of each auxiliary mold close to the auxiliary mold, and a guide net is disposed on the position of the main mold, which is not opposite to the auxiliary mold, and is far away from the molding surface of the main mold, so that the guide net covers the fiber layers in the entire mold cavity from above. Thus, in the present embodiment, resin is applied from the guide net to the resin nozzle (the glue injection port) in the molding process, and the resin is impregnated from the upper portion to the lower portion of the fiber layer.

Preferably, a plurality of glue ports are aligned with the surface channels on one side of the master mold and a plurality of vacuum-pumping nozzles are aligned with the surface channels on the opposite side of the master mold, respectively, so that resin flow-directing paths are provided during vacuum infusion by means of the channels on the master mold for forming the corrugation, helping to rapidly disperse and impregnate the fibrous layers. Whereby it is possible to omit the additional arrangement of the resin dispensing tube in the vacuum chamber.

In yet another aspect, in accordance with the preceding aspect, the temperature settings of the primary and secondary modes are differentiated, and secondary mode surface temperature is controlled to be lower than primary mode temperature.

In a further aspect of the invention there is provided a pipe section module prepared by the method described above.

With respect to the description of circumferential and longitudinal or axial directions, the object product of the present disclosure is a pipe segment module for assembly into a pipe segment and a pipe or duct, whether a mold or a product, is described for convenience of description with respect to the circumferential and axial directions and/or the central axis of the pipe segment, etc. Since the target product is produced by means of a mould, the main mould of which provides the basic profile of the product, said axial as well as circumferential direction also coincides with the pipe section modules and the assembled pipe sections.

[ advantageous effects of the present disclosure ]

First, the present disclosure provides a vacuum infusion process for producing a pipe section module which can assemble a pipe section having a large diameter end, and which is performed at a construction site, a plurality of pipe section modules are assembled in the site to form a pipe section providing a large diameter end, the pipe section constituting an end of the large diameter end to surround a small diameter end of a first pipe section by a site assembly operation, and then the plurality of pipe section modules providing the large diameter end are fastened to each other at adjacent edges in a longitudinal direction of the pipe or pipe section, whereby connection with the first pipe section in the axial direction of the pipe is completed while assembling a second pipe section.

The structure and method for connecting the large diameter end and the small diameter end by surrounding the large diameter end by a plurality of parts are different from the traditional spiral connection or socket connection between pipe sections, even the fastening operation is not necessarily operated at the joint or contact position of the large diameter end and the small diameter end, but can be operated only on the pipe section body, and the operation convenience is unexpected. The connection operation is repeated, so that the pipeline connection and the pipeline laying can be conveniently realized.

The improved vacuum filling process can not only realize the production of the products, but also effectively reduce the module investment and equipment investment, is particularly suitable for flexible design of the products, and is particularly suitable for research and development and supply of the products with special sizes, so that the market adaptability of the culvert pipes or the spliced cans prepared from the fiber reinforced plastics is stronger and more flexible.

The technical scheme of the present disclosure relates to two-sided molding of an article, but adopts a vacuum bagging process modified by the inventor instead of adopting a dual-mode vacuum infusion process in the prior art. The dual-mode vacuum filling process only adopts a die to form a closed vacuum cavity, and is difficult to operate aiming at large-size products required by the scheme, and neither manual die stripping nor equipment die stripping is ideal, so that the cost is increased. In addition, the process has difficulty achieving high glass fiber content and strength of the disclosed target products.

The technical scheme effectively provides a unique and innovative application mode of the vacuum bag pressing process, provides local double-sided molding of the product, designs unique fiber combination laying, positioning and product directional reinforcement aiming at a target product, and further improves and optimizes the mechanical property of the product under the condition of controlling the cost. And fully combining and utilizing the characteristics of the new technology, further enriching the configuration of the product and expanding the applicability and adaptability of the module product.

The technical scheme provided by the disclosure is particularly suitable for providing large-caliber pipeline products, the module provided by the disclosure is suitable for being assembled to form a composite material pipeline, and the mechanical property of the product is suitable for an underground device, in particular to engineering products such as an underground culvert or culvert pipe.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1 is a schematic perspective view of a pipe segment assembled from pipe segment modules of the present disclosure and 2 pipe segments ready for interconnection;

FIG. 2 is a schematic illustration of the receiving and sealing arrangement of the 2 pipe sections of FIG. 1 assembled;

FIG. 3 is a schematic perspective view of two pipe segment modules connected in tandem of the present disclosure, with the inner surface of the plate being curved;

FIG. 4 shows the outer surfaces of two sheets of material joined in tandem in an arc as shown in FIG. 3;

FIG. 5 is a cross-sectional view of a segment module in a direction orthogonal to the axial direction;

FIG. 6A is a schematic illustration of a seal configuration between pipe segments;

FIG. 6B is a schematic illustration of a seal configuration between pipe segments of another embodiment;

FIG. 7 is a schematic diagram of a primary and secondary die arrangement of an embodiment of the present disclosure;

FIG. 8 is a partial schematic cross-sectional view of the first secondary mold and article shown in FIG. 7;

FIG. 9 is a partial schematic cross-sectional view of the second secondary mold and article shown in FIG. 7;

FIG. 10 is a schematic diagram of a mold arrangement and layers of material lay-up;

FIG. 11 schematically illustrates the manner in which a fiber weave cloth is laid over a master mold;

FIG. 12 is a first embodiment of a vacuum nozzle and glue injection port arrangement on a master mold;

FIG. 13 is a schematic diagram of the assembly between the master and slave molds;

FIG. 14 is a second embodiment of a vacuum nozzle and glue injection port arrangement on a master mold; and

fig. 15 is a schematic view of an example of a receiving structure and a sealing structure.

Detailed Description

The present disclosure is described in further detail below with reference to the drawings and the embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant content and not limiting of the present disclosure. It should be further noted that, for convenience of description, only a portion relevant to the present disclosure is shown in the drawings.

In addition, embodiments of the present disclosure and features of the embodiments may be combined with each other without conflict. The technical aspects of the present disclosure will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Unless otherwise indicated, the exemplary implementations/embodiments shown are to be understood as providing exemplary features of various details of some ways in which the technical concepts of the present disclosure may be practiced. Thus, unless otherwise indicated, features of the various implementations/embodiments may be additionally combined, separated, interchanged, and/or rearranged without departing from the technical concepts of the present disclosure.

The use of cross-hatching and/or shading in the drawings is typically used to clarify the boundaries between adjacent components. As such, the presence or absence of cross-hatching or shading does not convey or represent any preference or requirement for a particular material, material property, dimension, proportion, commonality between illustrated components, and/or any other characteristic, attribute, property, etc. of a component, unless indicated. In addition, in the drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. While the exemplary embodiments may be variously implemented, the specific process sequences may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in reverse order from that described. Moreover, like reference numerals designate like parts.

When an element is referred to as being "on" or "over", "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or intervening elements may be present. However, when an element is referred to as being "directly on," "directly connected to," or "directly coupled to" another element, there are no intervening elements present. For this reason, the term "connected" may refer to physical connections, electrical connections, and the like, with or without intermediate components.

For descriptive purposes, the present disclosure may use spatially relative terms such as "under … …," under … …, "" under … …, "" lower, "" above … …, "" upper, "" above … …, "" higher "and" side (e.g., as in "sidewall"), etc., to describe one component's relationship to another (other) component as illustrated in the figures. In addition to the orientations depicted in the drawings, the spatially relative terms are intended to encompass different orientations of the device in use, operation, and/or manufacture. For example, if the device in the figures is turned over, elements described as "under" or "beneath" other elements or features would then be oriented "over" the other elements or features. Thus, the exemplary term "below" … … can encompass both an orientation of "above" and "below". Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when the terms "comprises" and/or "comprising," and variations thereof, are used in the present specification, the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof is described, but the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof is not precluded. It is also noted that, as used herein, the terms "substantially," "about," and other similar terms are used as approximation terms and not as degree terms, and as such, are used to explain the inherent deviations of measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art.

In the description of the present specification, reference to the terms "one embodiment/manner," "some embodiments/manner," "example," "a particular example," "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment/manner or example is included in at least one embodiment/manner or example of the application. In this specification, the schematic representations of the above terms are not necessarily for the same embodiment/manner or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments/modes or examples. Furthermore, the various embodiments/modes or examples described in this specification and the features of the various embodiments/modes or examples can be combined and combined by persons skilled in the art without contradiction.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

Application example of a pipe section Module

The present disclosure is directed to developing new processes, developing new molds, putting into preparation new products specifically designed to meet the requirements of configuration and mechanics, and one of its important applications is the manufacture of a pipe section module. For ease of understanding, examples of applications of the pipe segment module are described below by way of example.

As explained above, the present disclosure aims at further development of pipes made of composite materials, which have been developed by the inventors before much effort, and expanding the applicability of products with new processes. In particular, in this embodiment, the present disclosure uses new processes and improved configurations to make a tube segment module that can be applied to assembled culverts and ducts.

With respect to the pipe segment modules of the present disclosure, similar configurations to those of the previously developed SMC molding process can be made, but to accommodate the new process and to address the deficiencies of the new process, it is preferable to further provide configuration improvements with respect thereto. However, the tube segment module assembly steps and effects of the present disclosure are similar to the assembly and application of the previous SMC tube segment module, which is also one of the objects and technical effects to be achieved by the present disclosure.

Referring to fig. 1-6, fig. 1 illustrates a pipe segment module 90 (an article or product embodiment of the present disclosure) assembled circumferentially to form a first pipe segment 10 and a second pipe segment 20, which are joined axially to form a pipe assembly 1.

Fig. 1 illustrates a schematic perspective view of 2 pipe sections (first pipe section 10, second pipe section 20) to be connected to each other, wherein the left is the second pipe section 20 and the right is the first pipe section 10. Note that the pipe assembly 1 is assembled so as not to be directly plugged, as will be described later. Fig. 2 shows a pipe section socket structure, a strip groove 70 in the form of a groove and a sealing material, i.e. a spacer 30, which is a sealing strip, a sealing ring or the like.

Fig. 3 and 4 are perspective views of two pipe segment modules 90 removed from one back-and-forth connected 2 pipe segments, showing the inner and outer surfaces of two corrugated arced plates. Fig. 5 is a cross-sectional view of the pipe segment module 90 in a direction orthogonal to the axial direction.

The first pipe segment 10, which has been assembled, is provided with a small diameter end 60, and the second pipe segment 20, which has not yet been assembled, will be assembled from 3 pipe segment modules 90, so that the large diameter end 50 provided after assembly will be provided at its other end, while the small diameter end 60 will be provided at its other end, during the next pipe segment connection operation, or in the next pipe segment assembly connection mechanism, this second pipe segment 20 will be the "first pipe segment 10" in the next installation unit for providing the "small diameter end 60" on the right, whereby a periodical operation or arrangement is provided in the laying of the entire pipe.

The pipe sections are connected with each other to form a pipeline or a pipeline. The pipe assembly 1 is formed by connecting at least two pipe sections. For ease of description, the present disclosure is differentiated by the provision of a coupling mechanism, such as a small diameter end 60, a large diameter end 50, or a flange end, etc., during assembly of the pipe sections, and thus the pipe sections may be pipe section units that do not provide a coupling mechanism, either the first pipe section 10 that provides the small diameter end 60, or the second pipe section 20 that provides the large diameter end 50, as well as pipe sections that are provided with other types of coupling mechanisms.

In this example, the pipe sections are a first pipe section 10 (with a small diameter end) and a second pipe section 20 (with a large diameter end), respectively, and in this example, the first pipe section 10 and the second pipe section 20 have substantially the same configuration, but different connection pairing mechanisms are provided in one pipe section connection, respectively, so different naming is given for convenience in description and understanding of the technical solutions of the present disclosure. Thus, in this example, two pipe sections are each formed from at least two pipe section modules 90, with three pipe section modules 90 being shown in FIG. 1.

And (3) pipeline assembly:

1) The first pipe section 10 is provided, and the first pipe section 10 may be an assembled pipe section or an integrated pipe section, and only the small diameter end 60 needs to be provided as the first mounting mechanism.

2) The second pipe section 20 is provided, the second pipe section 20 is provided with a large diameter end 50, and it is composed of a plurality of pipe section modules 90, the pipe section modules 90 are provided with lateral connection mechanisms 80 on both sides, and the lateral connection mechanisms 80 are provided along the longitudinal or axial direction of the pipe section.

During assembly, the plurality of tube segment modules 90 of the second tube segment 20 are wrapped around the small diameter end 60 of the first tube segment 10 at the large diameter end 50 thereof, and adjacent lateral attachment means, such as lateral flanges, of each tube segment module 90 of the second tube segment 20 are secured to one another in the circumferential direction. The lateral flanges are positioned along the edges of each segment module 90 with the mounting holes between adjacent flanges aligned and secured by screw or rivet connections. Because the spacer 30 is disposed between the outer surface of the small diameter end 60 and the inner surface of the large diameter end 50, and the spacer 30 has a predetermined thickness or height, after the assembly is completed, the gap between the large diameter end 50 and the small diameter end 60 is partially filled, so that the large diameter end 50 and the small diameter end 60 are compressed, and a tight fit is achieved. Referring to fig. 6A and 6B, the combination of the bead groove 70 and the sealing bead (spacer 30) in this example provides a securing effect on the spacer 30, and utilizes the elastic deformability of the sealing bead to provide a further sealing effect between pipe segment joints in addition to the press fit effect of the assembly.

3) Upon completion of the above-described assembly, the second pipe segment 20 provides the small diameter end 60, whereby the second pipe segment 20 can continue to position the pipe segment module 90 of the other second pipe segment 20 correspondingly as the first pipe segment 10 in the next assembly unit, arrange the spacing means 30, provide the operation of the large diameter end 50 surrounding the small diameter end 60, and the third pipe segment, not shown, as the next second pipe segment 20, fix its adjacent lateral connection mechanisms 80 to each other.

Thereby, the small diameter end 60 of the second pipe section 20 which is fastened and mounted in the axial direction can be circumferentially surrounded by the multi-mold part of the other second pipe section 20, further forming a connection mechanism in which the large diameter end 50 surrounds the small diameter end 60. And (5) sequentially repeating the installation and pipeline assembly and laying.

Thereby, in the laying process of the pipeline, the pipe sections can be assembled and simultaneously connected.

In addition, although only the first pipe section 10 is presented in the application embodiment, the second pipe section 20 is used for the example of assembly. In practice, it is also possible to introduce, for example, other types of pipe sections, for example, both ends being small diameter ends, so that both ends are respectively connected with large diameter ends by means of a socket connection or the like. Alternatively, the other end is provided directly with a blocking structure or the like. Accordingly, the description will also be directed to pipe sections, and instead of the first pipe section 10, the second pipe section 20 will be described.

Two-pipe section module and preparation example

Brief description of the drawingsfigure vacuum infusion process (vacuum bag forming process) of the present disclosure

The fiber part in the fiber reinforced plastic can be carbon fiber, aramid fiber, glass fiber or the like. The resin may be an unsaturated resin, an epoxy resin, a polyurethane resin, or the like. The articles of the present disclosure are useful in large buried culverts or containers where fiberglass reinforced plastics are a lower cost option for cost control. Glass fiber reinforced plastics, i.e. composites of glass fibers and resins. Various glass fiber materials, such as chopped glass fibers, glass fiber cloth, glass fiber bundles formed of continuous fibers, and various resins, are commercially available.

According to the technical scheme, the pipe section module is prepared by adopting a vacuum introducing process (vacuum bag forming process). The molding process is that the intermediate material to be molded, namely, all fiber layers, auxiliary materials and the like are arranged, is sealed between a mold and a vacuum bag, and the intermediate product is pressurized by vacuumizing, so that the product is more compact and has better mechanical properties. The vacuum bag forming process is suitable for hand lay-up, spraying and prepreg forming processes, and can be matched with an oven, an autoclave and the like for use.

The pipe section module manufactured by the embodiment is suitable for further assembling large-diameter assembled pipelines/tank bodies. The mold cavity of the conventional vacuum bag molding process adopts a molding surface, in this embodiment, a double-sided mold cavity is adopted, that is, one surface of the product is provided with the molding surface (a first surface) by a main mold, the opposite surface (a second surface) of the product is provided with an auxiliary mold, the auxiliary mold provides the molding surface for a part in the second surface, and the rest part is provided with the vacuum bag limiting shape.

The vacuum bag compression molding of the large-diameter assembled pipeline/tank body has the advantages that:

(1) Compared with a winding forming pipeline: the diameter of the assembled and molded pipeline is not limited by the process, the winding and molded pipeline is limited by the transportation size, the maximum diameter is 3.2 meters, and the whole transportation is high in transportation cost.

(2) Compared with the mould-pressing spliced pipeline, the investment cost of mould equipment is lower, the investment cost of the mould for the vacuum bag pressing process is only 1/20 of the mould cost for the mould pressing process, and the size is not influenced by the height of a press table top and an opening like the mould pressing process.

(3) The defect is that the molding speed is low, and the disposable vacuum bag film and other auxiliary materials are consumed in the molding process.

2. Construction variations and examples of pipe segment modules of the present disclosure

The pressure imparted by the vacuum bagging process during the production process is mainly from the vacuum level in the mold cavity, as compared to the molding process. The vacuum action may assist in impregnating the fibrous layers with flowable materials such as resins, but the cavity pressure is much lower than during the molding process, which is a detrimental factor in the strength improvement of the product.

In order to make up the disadvantages, a unique process design is carried out for the preparation of the product, and the process comprises the steps of die setting, vacuum die cavity setting, fiber layer laying and product structure adjustment. For example, with respect to the configuration of the product, i.e., the configuration of the pipe segment module 90 as shown in fig. 1-6.

As shown in fig. 6A and 6B, both figures show different embodiments in which a spacer means (sealing strips, sealing rings, etc.) 30 is shown, as well as a groove (strip groove) 70, i.e. after the pipe section module 90 has been assembled into a circumferentially closed pipe section, the pipe section is provided with a strip groove 70 at its one end outer surface, in which strip groove 70 a spacer means 30 in the form of a sealing strip is placed, whereby one end of the other pipe section is secured around the end, forming a receiving connection between the two pipe sections, the strip groove 70 and the spacer means 30 means in the form of a sealing strip providing the sealing function.

Accordingly, the present disclosure requires at least one secondary mold to provide a configuration corresponding to the surface of one end region of the tube segment module 90 for forming the adhesive strip groove 70.

In a second embodiment shown in fig. 6B, a reinforcing structure is provided at both ends of the pipe segment module 90, for example, as shown in fig. 8 and 9, a small diameter end inner flange 200, a large diameter end first reinforcing rib (outer flange) 240, and a large diameter end second reinforcing rib 250 are added at both end regions, respectively. Fig. 8 and 9 also show these configurations provided by the first and second auxiliary dies.

As shown in fig. 9, the reinforcing ribs are added to the outer surface of the second end portion, and two reinforcing ribs, namely, a large diameter end first reinforcing rib 240 also can serve as an outer flange at one end of the pipe section, and a large diameter end second reinforcing rib 250 are provided in this embodiment. Depending on the different sizes of the products, only one reinforcing rib or more reinforcing ribs can be arranged. When multiple pipe sections are assembled into a pipe or highway culvert, such external flanges and ribs do not interfere with the socket connection between the pipe sections because they are disposed on the outer surface of the large diameter end 50 of the pipe sections.

By utilizing the features of the vacuum infusion process employed in the present disclosure, circumferentially arranged bundles of continuous fibers are added in the regions of the two ends of the article or pipe segment module 90, such as at the spaces between corresponding ribs, flanges, and grooves, by the unique design of the laid fibers. The fiber bundles are adapted to be received and secured in a rib-like structure on the outer surface of the product, which is particularly advantageous for providing reinforcement. In addition, the fiber fabric layers are additionally arranged at the two end regions, so that a wrapping effect is provided for the fiber bundles, and the strength of the two end regions is further improved. Other variations, including fiber layer lay-up of the article as a whole, provide unique fiber layer combination arrangements, as described below.

The pipe segment module 90 prepared using the unique process of the present disclosure is used to assemble pipe segments and pipe segment assemblies in the application examples above, with exemplary product parameters set forth in table 1.

The disclosed pipe section modules, also known as monolithic corrugated plates, are radian corrugated plates assembled into circumferentially closed pipe sections or tanks. The outer flange and the inner flange mechanism described above are further used as the tank body, and a closure plate and the like can be added to both ends of the pipe section.

Table 1 exemplary parameters of the application of the disclosed pipe segment modules (also known as monolithic corrugated plates) to the assembly of pipe products

SN: ring stiffness in KN/m ² Other dimensional units: mm (mm)

Referring to fig. 15 and table 2 below, the arrangement of the socket and spigot and rubber strip dimensions of the pipe segments and pipe segment assemblies in the above embodiments is illustrated. The socket configuration refers to the assembly between the small diameter end 60 and the large diameter end 50 of the pipe segment arrangement. The first pipe segment 10 is assembled to provide the small diameter end 60, and the corresponding portions of the large diameter ends of each pipe segment module 90, e.g., three pipe segment modules 90, of the second pipe segment 20 are wrapped around the small diameter end 60 while the adjacent lateral coupling mechanisms are secured to each other and tightened to provide the axial socket connection between the pipe segments. With this unique assembly step and design, small diameter end 60 is inserted into large diameter end 50, in effect large diameter end 50 is assembled around small diameter end 60 to achieve the insertion.

For ease of description, the concept of assembling small and large diameter ends of pipe sections is also employed with respect to each pipe section module 90, i.e., the unitary article provided by the present disclosure, i.e., the end regions of the article (first end region 290 and second end region 300) are used to construct small and large diameter ends 60 and 50, respectively, of the assembled pipe section.

To facilitate an understanding of the present disclosure, further examples of dimensions for the socket and rubber seal are provided, as illustrated in fig. 15 and the description provided in table 2. These designs include considerations such as, for convenience, placement of vacuum bags, drainage screens, release cloths, fibrous layers, etc. in the secondary mold inner grooves, it is preferable to provide a groove width of not less than 30mm, for example, a DN4000 tube, with a groove width of 40mm, a rubber hardness rating of preferably 70, and a rubber compression ratio of 30%, preferably a rubber ring diameter of about 2 times the groove depth, for example, 46mm.

TABLE 2

Socket position sizing (in mm) is illustrated with a tube of DN4000

Description: nominal diameter (nominal diameter), here the average of the net dimensions of the inner diameter, taking into account the height of the corrugations, removing the wall thickness. The D1 size is not referred to in this table.

3. Mold setting embodiment

In this embodiment, a main mold, namely a main mold 280, and two auxiliary molds, namely a first auxiliary mold 260 and a second auxiliary mold 270, are used. Referring to fig. 7, an arrangement of a first subsidiary mold 260, a second subsidiary mold 270, and a main mold 280 is schematically shown. The main die 280 is used to provide the overall configuration of the inner wall of the overall pipe segment module 90, which in this embodiment provides a smooth configuration of the inner surfaces of the first end region 290 and the second end region 300 of the pipe segment module 90, as well as a corrugated plate-like inner wall configuration therebetween. Although described in terms of corrugated sheets, in practice, the segment module 90 is curved, not flat, but rather has an axial direction and a curvature about the axial direction.

In the present disclosure, a secondary mold is used to provide a localized configuration of the second surface of the article. In this embodiment two secondary molds are provided to provide the configuration of the outer surface of the product in the front and rear end regions of the product.

As shown in fig. 8, the first secondary mold 260 provides a configuration of grooves 70 corresponding to the outer surface of the pipe segment module 90, where the grooves 70 in this embodiment provide a continuous groove 70, also referred to as a bead groove, for placement of a stripper ring or strip, or other sealing material, when the pipe segment module 90 is assembled to form a closed pipe segment. In addition, the first auxiliary die 260 is further configured to arrange the inner flange 200 at the forefront end of the product, and the inner flange 200 constitutes an annular inner flange after the product is assembled. The inner flange 200 may provide additional reinforcement and may also serve as a blind pipe blocking attachment means or as an attachment mechanism for other components, such as a elbow or the like. In addition, the first secondary mold 260 also provides a small diameter end transition 220 of the pipe segment module 90 configured to smoothly connect with the corrugated intermediate plate configuration of the pipe segment module 90.

The second auxiliary die 270, which provides a reinforcing rib structure, as shown in fig. 9, provides a first reinforcing rib (outer flange) 240 at the large diameter end, which is located at the rearmost end of the present product and protrudes from the outer surface, and may be configured as an outer flange, and likewise, the outer flange may be used as a connecting device for blind pipe plugging, or as a connecting mechanism for connecting other components, such as a elbow, as the inner flange 200 described above. Further, a second reinforcing rib 250 at the large diameter end can be provided to further enhance the product.

The second secondary mold 270 is configured to smoothly connect with the intermediate corrugated plate configuration of the pipe segment module 90, which provides the large diameter end transition 230 of the pipe segment module 90.

The large diameter end transition part 230 and the small diameter end transition part 220 are formed based on the design of two auxiliary molds, so that the parts connected with the corrugation of the corrugated plate arranged in the middle section area of the pipe section module 90 are of arc-shaped structures, the structure consistency with the corrugation of the upper surface of the corrugated plate is ensured, and the inner surface and the outer surface are in streamline transition, thereby facilitating the smooth laying of the vacuum diversion bag and reducing the accumulation of rich resin. 4. Inter-mold layup arrangement and vacuum bag arrangement

In the manufacturing process, the mold is layered with a mold release agent 310, a flow net 320, a mold release cloth 330, a reinforcing fiber layer 340, etc., and finally the mold cavity is wrapped and closed with a vacuum bag 350. Referring to fig. 10, the above-described ply arrangement is schematically shown.

4.1 layup on master mold 280 is set as follows:

4.1.1 applying a release agent 310 to the upper surface of the master mold 280 (here, the molding surface of the master mold 280) to the entire molding surface of the master mold 280;

4.1.2 laying up the reinforcing fiber layer 340 over the master mould 280 to the full moulding surface, where the laying up of the reinforcing fiber layer 340 is specifically as follows:

Lay-up of reinforcing fiber layer on 4.1.2.1 master 280:

(1) The forming surface nearest to the master mold 280 is first laid with a layer of chopped glass mat;

(2) Then, a fiber woven cloth is laid, as schematically illustrated with reference to fig. 11. In this embodiment, a plurality of layers of fiber woven cloth are laid on the main die 280, and a minimum of 4 layers, preferably 8-12 layers, are laid. Two kinds of fiber woven cloth are alternately laid on the upper layer and the lower layer: one layer is a thick cloth laid in the circumferential direction, which is called as the "circumferential thick cloth" again, and uses a fiber woven cloth with the width of 3 meters and the warp direction of 720 g/square meter, and the weft direction of 84 g/square meter to be laid on the main die 280 along the circumferential direction, wherein the circumferential direction refers to the conforming direction of assembling a closed ring with a product, and also refers to the direction approximately orthogonal to the axial direction penetrating through the front end and the rear end; the adjacent layers are laid axially, and a thin cloth is laid axially, which is called an axial thin cloth, wherein the fiber woven cloth with the width of 3 meters and the warp direction of 180 g/square meter and the weft direction of 20 g/square meter is laid along the axial direction of the main die 280 (the axial direction of the main die 280 is consistent with the axial direction of a product). The annular thick cloth and the axial thin cloth are alternately laid in a mode of upper and lower adjacent layers. "circumferentially thick" and "axially thin" refer to the former having a greater fabric density and basis weight than the latter. The fiber woven cloth is laid along the warp direction of the fabric. The direction parallel to the selvedge is the warp direction, and the other side is the weft direction. The design of the laying scheme considers the characteristics of the selected production process, and preferentially ensures the circumferential mechanical property of the product, so that the product meeting the practical performance is obtained in the most economical way.

The warp direction of the fiber woven cloth is the unwinding direction of the fiber woven cloth, so that the warp direction or the length direction is not limited in the laying process of products, and on the other hand, the width of the fiber woven cloth (or simply "cloth") is limited, and 3 m-wide cloth is selected in the embodiment, so that for large-size products, seam splicing is required in the laying process of the fiber woven cloth due to the limitation of the width.

As shown in fig. 11, taking a corrugated plate with a diameter of 4 meters (in this embodiment, a pipe section module 90 with radian is taken, three pieces are assembled into a pipe section with a diameter of 4 meters) as an example, a first layer of fiber woven cloth is laid on a main die 280, and is laid along a circumferential direction, as indicated by circumferential direction or circumferential arrow, a fiber woven cloth with a width of 3 meters is laid from left side to right side, and a circumferential seam is formed between two different cloth webs because the warp direction and the circumferential direction of the cloth are consistent, but there is a seam between the front cloth web and the rear cloth web, the front cloth web is 3 meters wide, the rear cloth web is 1.5 meters wide, and the circumferential seam is formed between the two cloth webs. In other words, fig. 11 shows that the cloth laid in the circumferential direction is butted with the cloth having a width of 3 m and a width of 1.5 m sequentially from front to back in the axial direction to form a seam when the first layer is laid.

Next, still referring to fig. 11, the axial arrows indicate laying of a second layer of woven fabrics, each laid back from front to back, with woven fabrics of 3 m-1.5 m width arranged contiguously in sequence from left to right.

Regarding the seam treatment of the fiber woven cloth on the same layer, in order to ensure the uniform thickness of the product, the two fiber woven cloths are in butt joint mode to form a seam, namely, the two fiber woven cloths are closely abutted on the edge and are not overlapped with each other, whether the two fiber woven cloths are laid in the axial direction or the circumferential direction.

The absence of overlapping seams introduces mechanical adverse effects. To eliminate this adverse effect, the staggered arrangement of the seams of the layers is further optimally designed. The following is continued with the above-mentioned three-piece assembled 4 meter diameter pipe section as an illustration of how to consider the feasibility of operation and maximize the staggered joint arrangement: 1) The first layer of annular thick cloth is paved, and the first layer of annular thick cloth is adjacently paved from front to back with a width of 3 meters and a width of 1.5 meters; 2) The second layer of axial thin cloth is paved, and 4 pieces of cloth with the width of 3 meters from left to right, and the width of 1.5 meters are adjacently paved; the third layer of annular thick cloth is paved, and two pieces of cloth with the width of 1.5 meters from front to back and the width of 3 meters are adjacently paved; the fourth layer of axial thin cloth is paved, and the first layer is paved adjacently from left to right with a width of 1.5 meters to 3 meters. Note also that the size of the woven cloth used in the axial direction is greater than the laid axial length due to the corrugated configuration on the master mould. For example, a module with a single length of 3 meters will have a larger cloth size from front to back due to the corrugated configuration, typically a width of about 4.5 meters for practical use, and will vary depending on the size of the wave height pitch.

The present embodiment preferably lays 12 layers in total, and the fifth to twelfth layers are processed in accordance with the laying manner of the first to fourth layers. The advantage of such laying is that the circumferential laying and the axial laying of the upper and lower adjacent layers are alternated, and the laying sequence between the layers with different circumferential laying is changed, so that the joint products between the upper and lower adjacent layers are mutually orthogonal; the joint between the two adjacent annular paving layers or the two adjacent axial paving layers is staggered. Therefore, the strength of the product is ensured, and the wall thickness of the product is ensured to be consistent.

4.1.3 the release cloth 330 is laid over the main mould 280 to the edges of the two auxiliary moulds (260, 270) and not under the two auxiliary moulds.

4.1.4 a guide wire 320 is then laid over the main die 280 to the edges of the two auxiliary dies (260, 270) and not under the two auxiliary dies (260, 270).

4.2 lay-up of auxiliary dies (not specifically illustrated, two auxiliary dies in this embodiment, namely, first auxiliary die 260, second auxiliary die 270)

4.2.1 application of Release agent 310 inside the auxiliary mold (lower surface/Forming surface)

4.2.2, paving a guide net 320 in the auxiliary die to the position of the guide net 320 of the main die 280 and overlapping the guide net with the width of about 10 cm;

4.2.3 laying a release guide 330 in the auxiliary mold and overlapping the release guide 330 of the main mold 280 by about 10cm

4.2.4 laying of the glass fibre layer 340 on the auxiliary mould: 2 layers of fiber woven cloth with the warp direction of 720 g/square meter and the weft direction of 84 g/square meter are paved in the attaching mould and cling to the mould layer along the circumferential direction, and then continuous glass fiber bundles are paved in the mould groove, wherein the continuous glass fiber bundles are fiber bundles which are not woven into cloth until the mould groove is filled. The formed glass fiber cloth layer completely wraps the glass fiber bundles. The glass fiber bundles can enter the strip-shaped grooves of the die more easily, the strip-shaped grooves are correspondingly provided with reinforcing ribs, or the partition walls between the adhesive tape grooves, or the inner flange, the outer flange and other configurations, and the fiber bundles can be laid in a manner of economically improving the compressive strength of the ribs in the circumferential direction of the pipeline to the greatest extent and can flow into the narrow grooves to be in place more easily than the fiber woven cloth. Therefore, the fiber distribution state of the glass fiber bundles is completely wrapped by the glass fiber cloth layer after molding is specially designed, and the mechanical property of the product is optimized.

And 4.3, after the main and auxiliary dies are locked by the positioning bolts, adhesive tapes are adhered to the upper surfaces of the peripheries of the auxiliary dies, so that the adhesive tapes are sealed with the vacuum bag, and resin adhesive liquid is prevented from entering the upper surfaces of the auxiliary dies. And a vacuum bag is integrally paved on the upper surface of the main die and the auxiliary die, the width of the vacuum bag is larger than the width of the periphery of the main die by about 20cm, and the adhesive tape and the vacuum bag are well sealed.

5. Vacuum pumping and glue injection hole arrangement

A vacuum suction spiral pipe may be laid on one side of the mold, a plurality of vacuum suction nozzles 390 are connected to the vacuum suction spiral pipe, a resin runner groove is laid on the other side, a plurality of glue injection ports 380 are provided on the resin runner groove, and the resin paste flows from one side of the mold to the other side of the mold by means of a groove forming runner and vacuum pressure (see fig. 13). Therefore, the resin flow guide pipe can be omitted from being paved in the vacuum cavity. Vacuum equipment, resins, and the like are commercially available.

A resin-supplying injection port 380 is disposed above the guide net, and the injection port 380 on the master mold positions a groove position on the master mold, whereby a runner of the resin is provided by means of the groove.

Upper and lower molds are used at both ends of the product, i.e. the main mold 280 is a lower mold and two auxiliary molds are upper molds, and the vacuum bag entirely encloses the auxiliary molds, and optionally, further, the vacuum bag is further fixed at the edge of each auxiliary mold to prevent resin from flowing into the outer surface of the auxiliary mold. And sealing and fixing the periphery of the vacuum bag at the outer edge of the main die. Thus, the molding surface of the main mold, the molding surface of the auxiliary mold and the vacuum bag form a communicated vacuum mold cavity.

The upper portions of both ends of the main mold 280 face the two auxiliary molds respectively, so that the flow rate of the resin at the position is slowed down, and therefore, separate glue injection ports 380 and vacuum suction nozzles 390 are arranged at the positions corresponding to the auxiliary molds at both ends of the main mold 280, so as to increase the local pressure and accelerate the local flow of the resin.

To prevent the fill port 380 and the vacuum nozzle 390 from clogging, the fill port 380 and the vacuum nozzle 390 extend to the guide screen below the auxiliary die to ensure efficient removal of gas and efficient flow of resin. Bolts for fastening the auxiliary mold are provided outside the glue injection port 380 (fig. 13), and also outside the vacuum nozzle 390 (not shown in the drawing, which is disposed on the other side in a manner consistent with the glue injection port 380 described above), preventing the resin from sticking to the bolts.

6 clamping and fixing of auxiliary dies at two ends

Auxiliary mold mounting grooves 410 are provided at positions of the main mold 280 as shown in fig. 13, corresponding auxiliary molds are placed in the auxiliary mold mounting grooves 410 at both ends of the main mold 280 and are fixed with fixing bolts 400 of the main mold and the auxiliary mold, and the fixing bolts 400 of the main mold and the auxiliary mold are provided outside the glue injection port 380 and the vacuum nozzle 390 in order to prevent the resin from sticking the bolts and to avoid the bolts from blocking the glue injection passage and the vacuum suction passage.

Examples of temperature, resin viscosity and temperature of the primary and secondary mold

Examples of the combined control and setting of the master, slave, resin viscosity and temperature are given below as shown in table 3 to facilitate an understanding of the present invention.

Table 3 examples of mold temperature, resin viscosity and temperature settings

8 Process control for vacuum infusion operations

8.1, connecting vacuum spiral pipelines of a vacuum gauge, starting vacuumizing, continuously vacuumizing for 8-12 minutes after the vacuum degree on the pressure gauge reaches 0.1MPa, closing a valve of a vacuum pump, and if the vacuum pressure on the pressure gauge is reduced by less than-0.002 MPa within 5 minutes, judging that the vacuum degree of the system is qualified; generally, a movable vacuumizing device is adopted, 2 vacuum pumps are arranged, two pumps are started during filling, and one pump is closed after filling is completed.

8.2, after the vacuum is qualified, optionally, paving a second layer of vacuum bag for safety, and vacuumizing again, so as to perform vacuum test in the previous step and meet the requirement.

8.3 checking if the mold surface temperature, the master 280 has been controlled between 30-35 c and the slave 28-30 c, if not, and adjusting the mold heating system to achieve this.

8.4 closing all doors and windows to ensure that the air in the workshop is stable and no convection occurs, otherwise, the uneven surface temperature of the product can be caused, and the dangerous phenomena such as uneven resin flow rate and the like can be caused.

8.5 checking the surface temperature of the product, if the difference between the surface temperature of the product and the surface temperature of the mould is less than 3 ℃, the next step can be performed, otherwise, a cover needs to be added on the surface of the product, so that the temperature of the whole thickness of the product is uniform.

8.6 measuring the temperature of the mixed resin, wherein the temperature is between 27 and 30 ℃, and correspondingly the viscosity is between 150 and 250cps, so that the flow characteristic of the resin can be judged to be qualified. If the temperature is too high, the temperature needs to be reduced by adopting equipment such as an air conditioner and the like; if the temperature is too low, it is necessary to heat the temperature of the resin component material to raise the temperature of the resin after mixing and accelerate the flow.

8.7 in order to remove a large amount of bubbles from the resin, the resin was placed in a closed steel vessel, evacuated for 5 minutes, and then poured into the product under a vacuum pressure of 0.lMPa.

8.8 first the two end auxiliary mold positions of the glue injection ports 380 were opened, then the middle 4 glue injection ports 380 were opened.

8.9 resin infusion was performed. Since the two auxiliary molds and the guide net at the main mold 280 are arranged on the upper side of the fiber layer, the resin is impregnated with the glass fiber from top to bottom.

8.10 the vacuum pressure is kept unchanged, 0.1MPa, the mold temperature and the ambient temperature are kept unchanged, and the resin temperature can rise by 2-3 ℃ in the whole pouring process, which is the allowable condition.

8.11 the resin is poured in an amount of about 0.30 to 0.32 times the total weight of the fiberglass cloth blanket.

8.12, closing the filling valve after filling is finished. Curing is continued for 4-5 hours, and demoulding is carried out.

Second embodiment of arranging glue nozzle and vacuum device

Additional glue dispensing ports 380 and vacuum nozzle 390 arrangements are also contemplated, corresponding to the particular configuration of the subject product of the present disclosure. The main die 280, as well as the secondary dies (first secondary die 260 and second secondary die 270), are provided with circumferentially extending grooves or recesses, i.e., corresponding to the corrugated configuration on the main die, and the ribs or grooves of the secondary dies, which provide circumferentially extending recess and protrusion configurations on the die. With this configuration, another glue injection method is proposed, as shown in fig. 14, a vacuum filling cavity is arranged, a plurality of glue injection ports 380 penetrate the vacuum bag to be disposed at the highest position of each wave crest directly above the laid main mold 280, and a vacuum suction nozzle 390 is disposed around the main mold 280, and the vacuum suction nozzle 390 shown in fig. 14 is disposed opposite the groove at the groove portion of the corrugated structure of the main mold, in which, on both sides parallel to the extending direction of the groove, along the edges, in order to enhance the vacuum effect of the auxiliary mold near the edge of the vacuum cavity, and the sealing and evacuating effects for the first auxiliary mold 260 and the second auxiliary mold 270. In addition, one glue injection port 380 is provided at the highest point of the two auxiliary molds penetrating through the first auxiliary mold 260 and the second auxiliary mold 270, respectively.

This arrangement, which is another type of mold configuration corresponding to the product, optimizes the runner arrangement of the resin in the production process, and improves the resin flow and impregnation effect on the fiber layer.

Other variant embodiments

The present disclosure selects a typical application to be a tube segment module, i.e., a single piece article for assembling tube segments, which may be further assembled into a culvert, and which may be of the same configuration or of different configurations, so long as they can be assembled to each other into a culvert. In addition, the one-piece articles of the present disclosure are also suitable for assembly into large-sized cans. For example, the assembled individual pipe sections have an inner flange at the front end and an outer flange at the rear end, each of which can be engaged with a different closure member. Furthermore, the pipe segment modules themselves may have different configuration changes, for example, depending on the application, both ends may be provided with portions constituting the inner flange or both ends may be provided with portions constituting the outer flange. In addition, the second secondary mold may not be employed if the second end region of the pipe segment does not require an outer surface configuration.

The thickness of the product can be adjusted according to the application scene and the size of the product, so that the temperature of the mold and the like in the process, the viscosity of the resin, the arrangement of the vacuum pipes and the arrangement of the glue injection ports 380, and the like are properly adjusted.

In the above solution of the present disclosure, the optimization of the laying of the fiber layer based on the master mold is fully considered first, the emphasis is that the circumferential laying and the axial laying are alternately performed, and the fiber woven fabric laid in the circumferential direction is larger than the fiber woven fabric laid in the axial direction, so that the laying operation is significantly biased to the strength in the circumferential direction of the module, that is, the circumferential strength of the product body assembled into the pipe section and the tank body is considered, further, the circumferential laying and the axial laying are alternately performed, the joint areas of the layers are approximately orthogonal, the shortage of the strength of the joint is effectively dispersed, and further, although the two separated layers are both laid in the axial direction or are laid in the circumferential direction, for example, the laying of the non-whole cloth can be put at different positions, thereby further staggering the joint of the phase-separated layers. Thus, the laying of the multi-layered fiber cloth, even if the butt joint type seam is adopted, maximally limits the scattered seam and the staggered seam, and the seam orientation is crossed, thereby improving the fiber reinforcement effect.

The present disclosure includes at least the following concepts:

concept 1. A method of manufacturing a fibre reinforced plastic pipe section module, said pipe section module comprising at least a first surface and a second surface, and a first end region and a second end region arranged at both axial ends of said pipe section module, two or more pipe section modules being arranged in the same axial direction and being connected in circumferential direction for obtaining a circumferentially closed pipe section,

the manufacturing method adopts a vacuum lead-in forming method and is characterized in that,

the die device is provided with:

a master mold providing the first surface configuration;

a first secondary mold providing a configuration of the second surface of the first end region;

a second secondary mold providing a configuration of a second surface of the second end region;

Wherein the main mould provides a corrugated configuration arranged substantially parallel between the first end region and the first end region of the pipe section module, the corrugated configuration being constituted by an alternating arrangement of elongated recesses and elongated protrusions in the axial direction, and,

the molding surface of the first auxiliary mold is provided with at least one protruding strip structure for forming a rubber strip groove on the outer surface of the first end area of the pipe section module, the rubber strip groove extends along the circumferential direction, and

said second secondary mould forming surface being provided with at least one groove formation extending substantially in said circumferential direction for forming a reinforcing rib on the outer surface of the second end region of the pipe section module,

removably fixing the main mold to the first auxiliary mold and the second auxiliary mold, and,

the vacuum forming bag is arranged so that the main die, the first auxiliary die and the second auxiliary die, together with the vacuum forming bag, form a communicated and shared vacuum filling cavity.

Concept 2. The method of concept 1, wherein a configuration for providing an inner flange configuration at an end of the first end region is further provided on the first secondary mold.

Concept 3. The method of concept 1, wherein a configuration providing an outer flange configuration at an end of the second end region is further provided on the second secondary mold.

Concept 4. The method according to concept 1, comprising the step of laying down a plurality of functional layers and a fibre layer on the master mould, the fibre layer being arranged to: paving a layer of chopped glass fiber mat from the molding surface close to the main mold to the molding surface far from the main mold, wherein the whole molding surface of the main mold is covered; laying at least two layers of fiber woven fabrics on the whole molding surface of the main mold in close proximity to the chopped glass fiber mat, wherein the fiber woven fabrics of the same layer form joints in a butt joint mode, the joints of the fiber woven fabrics of the same layer are approximately orthogonal to the joints of the fiber woven fabrics of the adjacent layer, and the joints of the fiber woven fabrics of the separated layers are approximately parallel and staggered; and

and arranging fiber layers on molding surfaces of the first auxiliary mold and the second auxiliary mold respectively as follows: and arranging at least one layer of fiber woven cloth close to the molding surface of the auxiliary mold, and then arranging continuous glass fiber bundles extending along the circumferential direction to fill the grooves on the molding surfaces of the first auxiliary mold and the second auxiliary mold.

Concept 5. The method of concept 4, wherein at least two layers of fiber woven cloth laid over the entire forming surface of the master mold are arranged to lay one layer of hoop thick cloth circumferentially, and adjacent layers are arranged to lay one layer of axial thin cloth axially, the hoop thick cloth having a greater grammage than the axial thin cloth.

Concept 6. The method of concept 4, wherein 6-14 layers of fiber woven cloth are laid over the entire forming surface of the master mold.

Concept 7. According to the method of concept 1, a guide net is provided on the molding surface of each auxiliary mold close to the auxiliary mold, and a guide net is provided on the main mold at a position far from the molding surface, so that each guide net covers the fiber layer in the vacuum infusion cavity from above.

Concept 8. The method of concept 1, wherein the temperature settings of the primary and secondary modes are differentiated and the secondary mode surface temperature is controlled to be lower than the primary mode temperature.

Concept 9. The method of concept 7, comprising disposing a plurality of glue injection ports at a top of the vacuum infusion chamber, wherein the plurality of glue injection ports are disposed in peaks of the corrugated configuration and in top openings of the first and second auxiliary dies, respectively.

Concept 10. A pipe segment module, characterized in that the pipe segment module is manufactured by the method according to concepts 1 to 9.

It will be appreciated by those skilled in the art that the above-described embodiments are merely for clarity of illustration of the disclosure, and are not intended to limit the scope of the disclosure. Other variations or modifications will be apparent to persons skilled in the art from the foregoing disclosure, and such variations or modifications are intended to be within the scope of the present disclosure.

Claims

1. A method of manufacturing a fibre reinforced plastic pipe section module comprising at least a first surface and a second surface, and a first end region and a second end region arranged at both axial ends of the pipe section module, two or more pipe section modules being arranged in the same axial direction and being connected in the circumferential direction for obtaining a circumferentially closed pipe section,

the die device is provided with:

a master mold providing a configuration of the first surface;

Wherein the main mould provides a corrugated configuration arranged substantially parallel between the first and second end regions of the pipe section module, the corrugated configuration being constituted by an alternating arrangement of elongated recesses and elongated protrusions in the axial direction, and,

2. The method of claim 1, further providing a configuration on the first secondary die for providing an inner flange configuration at an end of the first end region.

3. The method of claim 1, wherein a configuration is further provided on the second secondary die that provides an outer flange configuration at an end of the second end region.

4. The method according to claim 1, comprising the step of laying down a plurality of functional layers and a fibre layer on the master mould, the fibre layer being arranged to: paving a layer of chopped glass fiber mat from the molding surface close to the main mold to the molding surface far from the main mold, wherein the whole molding surface of the main mold is covered; laying at least two layers of fiber woven fabrics on the whole molding surface of the main mold in close proximity to the chopped glass fiber mat, wherein the fiber woven fabrics of the same layer form joints in a butt joint mode, the joints of the fiber woven fabrics of the same layer are approximately orthogonal to the joints of the fiber woven fabrics of the adjacent layer, and the joints of the fiber woven fabrics of the separated layers are approximately parallel and staggered; and

5. The method of claim 4, wherein at least two layers of fiber woven cloth laid over the entire forming surface of the main die are arranged to lay circumferentially one layer of circumferentially thick cloth, and adjacent layers are arranged to lay axially one layer of axially thin cloth, the circumferentially thick cloth having a greater grammage than the axially thin cloth.

6. The method of claim 4, wherein 6-14 layers of fiber woven cloth are laid over the entire forming surface of the master mold.

7. The method of claim 1, wherein a guide net is provided on the molding surface of each auxiliary mold close to the auxiliary mold, and a guide net is provided on the main mold at a position far from the molding surface, so that each guide net is a fiber layer covering the vacuum infusion chamber from above.

8. The method of claim 1, wherein the temperature settings of the primary and secondary modes are differentiated and the secondary mode surface temperature is controlled to be lower than the primary mode temperature.

9. The method of claim 7, comprising disposing a plurality of glue injection ports at a top of the vacuum infusion chamber, wherein the plurality of glue injection ports are disposed in peaks of the corrugated configuration and in top openings of the first and second auxiliary dies, respectively.

10. A pipe section module, characterized in that it is manufactured by a method according to any one of claims 1 to 9.