A corrosion-resistant pipe and forming method thereof

Abstract

The present invention discloses a corrosion-resistant pipeline and a forming method thereof. The corrosion-resistant pipeline comprises an inner tube and a composite material layer, wherein the composite material layer is prestressed and wound around the outer side of the inner tube; the composite material layer comprises glass fiber and epoxy resin, wherein the glass fiber is impregnated with the epoxy resin and the glass fiber containing the epoxy resin is wound around the circumferential outer side of the inner tube. The corrosion-resistant pipeline and the forming method thereof provided by the present invention are applicable to a limestone wet desulfurization system, have a reasonable structure, are reliable to use, are widely used in pipelines through which limestone slurry flows, effectively prevent corrosion of the pipeline, and at the same time, ensure the strength of the pipeline, extend the service life of the pipeline in the limestone wet desulfurization system, and improve the stability of the operation of the wet desulfurization system.

Description

Technical Field

[0001] The invention belongs to the technical field of wet flue gas desulfurization and relates to a corrosion-resistant pipeline and a forming method thereof. Background Art

[0002] Thermal power plants are a type of power generation that mainly uses coal to burn. The combustion of coal produces a large amount of flue gas containing harmful substances, such as sulfur dioxide. With the development of the power industry, sulfur dioxide has become increasingly polluting the environment. In order to eliminate environmental pollution, limestone wet desulfurization technology is widely used in power plants, which has a high desulfurization efficiency. During operation, limestone powder reacts with sulfur dioxide in the flue gas in the desulfurization reaction tower, eliminating about 90% of the sulfur dioxide in the flue gas, thereby generating gypsum slurry with a water content of 80%.

[0003] In the limestone wet flue gas desulfurization system, a large amount of gypsum slurry is produced. The gypsum slurry contains a large number of particles. Ordinary pipes have poor wear resistance and corrosion resistance and an extremely short service life. Especially at the inlet of the gypsum slurry pump and the limestone slurry return to the top of the limestone slurry tank, the pipes are prone to excessive wear and tear, causing pipeline leakage, which seriously affects the smooth operation of the limestone wet flue gas desulfurization system.

[0004] Therefore, it is urgent to design a corrosion-resistant pipeline and a forming method thereof to solve the existing technical problems. Summary of the invention

[0005] The purpose of the present invention is to solve some of the technical problems existing in the prior art to at least a certain extent, and to provide a corrosion-resistant pipeline and a forming method thereof, which are suitable for a limestone wet desulfurization system. The pipeline has a reasonable structure and is reliable to use. It is widely used in pipelines through which limestone slurry flows, and can effectively prevent corrosion of the pipeline. At the same time, the strength of the pipeline is ensured, the service life of the pipeline in the limestone wet desulfurization system is extended, and the stability of the operation of the wet desulfurization system is improved, and the pipeline has good promotion value.

[0006] In order to solve the above technical problems, the present invention provides a corrosion-resistant pipe, which includes an inner pipe and a composite material layer, wherein the composite material layer is prestressed and wrapped around the outer side of the inner pipe; the composite material layer includes glass fiber and epoxy resin, the glass fiber is impregnated with the epoxy resin and the glass fiber containing the epoxy resin is wrapped around the circumferential outer side of the inner pipe.

[0007] In some embodiments, the composite material layer further includes a curing agent, and the weight ratio of the curing agent to the epoxy resin is 1:10.

[0008] In some embodiments, the glass fiber containing epoxy resin is prestressed and wound around the outside of the inner tube, and the prestress is no more than 50 MPa.

[0009] In some embodiments, the glass fiber is prestressed on the inner tube in a decreasing layer-by-layer manner, and there are twelve layers of glass fiber wrapped around the outer side of the inner tube, and the prestress of the first layer of glass fiber is 45 MPa.

[0010] In some embodiments, the glass fiber is circumferentially wound around the circumferential outer side of the inner tube, and the winding angle is no greater than 15°.

[0011] In some embodiments, the glass fiber containing epoxy resin is wound around the inner tube to form a glass fiber composite material, and then subjected to rotational curing molding. The curing temperature is 60° C. and the curing time is 120 min.

[0012] In some embodiments, the volume ratio of the glass fiber to the composite material layer is not less than 80%.

[0013] In some embodiments, the thickness ratio of the inner tube to the composite material layer is 1:1.2.

[0014] In some embodiments, the inner tube is 316L stainless steel.

[0015] At the same time, the present invention also discloses a method for forming a corrosion-resistant pipeline, which comprises the following steps:

[0016] S1, the inner tube is fixed on the winding device by the inner expansion mandrel, and the winding device drives the inner tube to rotate;

[0017] S2, overlapping the glass fiber at the end of the inner tube, impregnating the glass fiber with epoxy resin and winding the glass fiber containing epoxy resin to the circumferential outer side of the inner tube;

[0018] S3, placing the assembly formed by the inner tube and the composite material layer in a curing device for curing;

[0019] S4, remove the inner expansion mandrel.

[0020] Beneficial effects of the present invention:

[0021] The present invention provides a corrosion-resistant pipeline and a forming method thereof, which are suitable for a limestone wet desulfurization system, have a reasonable structure, are reliable to use, are widely used in pipelines through which limestone slurry flows, effectively prevent corrosion of the pipeline, and at the same time, ensure the strength of the pipeline, extend the service life of the pipeline in the limestone wet desulfurization system, improve the stability of the operation of the wet desulfurization system, and have good promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above advantages of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings, which are only exemplary and do not limit the present invention, wherein:

[0023] Figure 1 It is a structural schematic diagram of a corrosion-resistant pipeline according to the present invention;

[0024] Figure 2 is a schematic diagram of applying prestress to each layer of the composite material layer of the present invention;

[0025] Figure 3 It is a structural schematic diagram of the winding device of the present invention;

[0026] Figure 4 It is a schematic diagram of glass fiber winding of the present invention.

[0027] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0028] 10-inner tube; 20-composite material layer; 30-three-jaw chuck; 40-tailstock; 50-moving trolley; 60-glass fiber roll; 70-glue constant temperature device; 80-pressing wheel; 100-winding device. DETAILED DESCRIPTION

[0029] Figure 1 This is a schematic diagram of a corrosion-resistant pipeline and a forming method thereof described in the present application. The present invention is described in detail below in conjunction with specific embodiments and drawings.

[0030] The embodiments described herein are specific embodiments of the present invention, which are used to illustrate the concept of the present invention, are illustrative and exemplary, and should not be interpreted as limiting the embodiments of the present invention and the scope of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the claims and the contents disclosed in the specification of this application, including technical solutions that adopt any obvious replacement and modification of the embodiments described herein.

[0031] The drawings of this specification are schematic diagrams, which assist in explaining the concept of the present invention and schematically show the shapes of various parts and their mutual relationships. Please note that in order to clearly show the structures of various components of the embodiments of the present invention, the drawings are not drawn according to the same scale. The same reference numerals are used to represent the same parts.

[0032] A structural schematic diagram of a corrosion-resistant pipeline described in this application is as follows Figure 1 As shown, it includes an inner tube 10 and a composite material layer 20, wherein the composite material layer 20 is prestressed and wound around the outer side of the inner tube 10; the composite material layer 20 includes glass fiber and epoxy resin, the glass fiber is impregnated with the epoxy resin and the glass fiber containing the epoxy resin is wound around the circumferential outer side of the inner tube 10.

[0033] As an embodiment of the present invention, the inner tube 10 has super wear resistance, and can be one of stainless steel, heat-resistant steel, and wear-resistant steel, such as high manganese steel, such as 60Mn, ZGMn13; the inner tube 10 can also be 316L stainless steel, and the inner wall of the inner tube 10 contacts the particles in the gypsum slurry with almost no or little wear.

[0034] As another embodiment of the present invention, the composite material layer 20 also includes a curing agent, and the weight ratio of the curing agent to the epoxy resin is 1:10. The epoxy resin and the curing agent can be in a liquid state at room temperature, so that the glass fiber used for winding can be soaked in the composition of the epoxy resin and the curing agent. During the winding process, the glass fiber lays the composition on the outer peripheral side of the inner tube 10; after the composite material layer formed by the epoxy resin, the curing agent and the glass fiber on the outer side of the inner tube 10 is wound and formed, it needs a curing process to increase the hardness of the composite material layer 20. The composite material layer has good corrosion resistance and can be applied to wet limestone desulfurization.

[0035] In the present invention, the glass fiber containing epoxy resin is prestressed and wound on the outside of the inner pipe 10, and the prestress is not more than 50Mpa. The use of prestressed wet winding can effectively improve the strength of the corrosion-resistant pipeline and meet the strength requirements of the pipeline in the limestone wet desulfurization system.

[0036] In some embodiments, the glass fiber is applied with prestress on the inner tube 10 in a layer-by-layer decreasing manner, and the glass fiber layer wrapped around the outer side of the inner tube 10 has twelve layers, and the prestress of the first layer of glass fiber is 45Mpa. Figure 2 The prestress of each layer of the composite material layer 20 during the winding process is shown. Figure 2 The prestressed winding shown can ensure the stability of the performance of the composite material layer. It is understandable that the number of layers of the composite material layer 20 and the corresponding prestress are not limited thereto, and it can also be wound on the outer side of the inner tube 10 with 8 layers, 10 layers or 16 layers, and the prestress applied by the glass fiber only needs to decrease layer by layer and meet the strength requirements.

[0037] As an embodiment of the present invention, the glass fiber is wound around the circumferential outer side of the inner tube 10, and the winding angle θ is not greater than 15° ( Figure 4 ). Preferably, the winding angle is 13°. The glass fibers are laid according to this winding angle and are densely laid on the outside of the inner tube 10, which is conducive to forming a good composite material layer, thereby ensuring good wear resistance.

[0038] In the invention, the glass fiber containing epoxy resin is wound around the inner tube 10 to form a glass fiber composite material, and then subjected to rotational curing and molding, the curing temperature is 60°C, and the curing time is 120 minutes. After the composite material layer 20 outside the inner and outer 10 is wound, it is in a liquid state at room temperature, and a temperature higher than room temperature is required to cure the composite material layer to form a complete composite material layer with a certain strength. After a curing temperature of 60°C and a curing time of 120 minutes, the composite material layer 20 is cured and molded to form a corrosion-resistant layer.

[0039] As an embodiment of the present invention, the volume ratio of the glass fiber to the composite material layer 20 is not less than 80%. Preferably, the volume ratio of the glass fiber to the composite material layer 20 is 85%, so that the corrosion-resistant pipe formed has higher strength and better corrosion resistance.

[0040] In some embodiments, the thickness ratio of the inner tube 10 to the composite material layer 20 is 1:1.2. Since the composite material layer 20 has good strength and corrosion resistance, it does not need to be equipped with a thicker rubber lining layer in the traditional technology, which effectively reduces the volume of the pipeline in the limestone wet flue gas desulfurization system and improves the convenience of pipeline construction. As an embodiment of the present invention, the thickness of the composite material layer 20 is 2-5 mm, preferably, the thickness of the composite material layer 20 is 3 mm, which effectively reduces the volume of the pipeline in the limestone wet flue gas desulfurization system and improves the convenience of pipeline construction.

[0041] At the same time, the present invention also discloses a method for forming a corrosion-resistant pipeline, which comprises the following steps:

[0042] S1, the inner tube 10 is fixed on the winding device by the inner expansion mandrel, and the winding device drives the inner tube 10 to rotate;

[0043] Specifically, the inner expansion mandrel is installed on the inner wall of the inner tube 10, and one end of the inner expansion mandrel is fixed on the three-jaw chuck 30 of the winding device 100, such as Figure 3 As shown, the other end is supported by the tailstock 4 of the winding device 100. The winding device rotates under the drive of the servo motor, thereby driving the inner tube 10 to rotate; further, the winding device 100 also includes a moving trolley 50, which is arranged on one side of the bed of the winding device 100, and is arranged on a ball screw through a slider. The ball screw is driven by another servo motor to drive the moving trolley 50 to move linearly along the ball screw; the moving trolley 50 is provided with a glass fiber roll 60, a glue constant temperature device 70 and a crimping wheel 80. The glass fiber roll 60 passes through the glue constant temperature device 70 and is then guided to the circumferential outer side of the inner tube 10 via the crimping wheel 80, as shown in FIG. Figure 4 As shown, during the winding operation, the inner tube 10 rotates while the moving trolley 50 drives the glass fiber filaments to move linearly along the axis direction of the inner tube 10 to complete the hoop winding of the glass fiber. Figure 3 and Figure 4 The structure of the winding device is briefly described schematically. It can be understood that the wet winding of glass fibers can be achieved in this manner. Figure 4 Schematic diagram of glass fiber winding, glass fiber roll 60, glue constant temperature device 70 and wire pressing wheel are all arranged on the mobile small tester 50.

[0044] During the winding process, the rotation speed of the inner tube 10 is 80-120 rpm, which can effectively prevent the composition formed by the epoxy resin and the curing agent from being splashed to the surrounding side of the winding device under the action of centrifugal force during the winding process and affecting the normal winding operation of the inner tube.

[0045] S2, overlapping the glass fiber at the end of the inner tube 10, impregnating the glass fiber with epoxy resin and winding the glass fiber containing epoxy resin to the circumferential outer side of the inner tube 10;

[0046] Specifically, the composition formed by the epoxy resin and the curing agent is placed in a glue constant temperature device 70, and a constant temperature device is arranged outside the glue constant temperature device 70, so that the composition configured with the epoxy resin and the curing agent is controlled within a constant temperature range to ensure the stability of the performance of the configured composition and improve the stability of the characteristics of the composite material formed by winding.

[0047] S3, placing the assembly formed by the inner tube 10 and the composite material layer 20 in a curing device for curing;

[0048] Specifically, the curing process temperature of the composite material is 60°C and the curing time is 120 minutes. In order to prevent the composition configured with epoxy resin and curing agent from gathering on the lower side of the inner tube 10 under the action of gravity during the curing process, during the curing process, the inner tube 10 and the composite material layer 20 need to rotate around the axis of the inner tube 10 at a certain speed to improve the relative uniformity of the composite material layer 20 on the outside of the corrosion-resistant pipe.

[0049] S4, remove the inner expansion mandrel.

[0050] Finally, after the corrosion-resistant pipe is solidified and formed, it can be installed and used in the limestone wet desulfurization system by simply removing the inner expansion core shaft to improve the corrosion resistance of the system pipeline.

[0051] Compared with the shortcomings and deficiencies of the prior art, the present invention provides a corrosion-resistant pipeline and a forming method thereof, which is suitable for a limestone wet desulfurization system. It has a reasonable structure and is reliable to use. It is widely used in pipelines through which limestone slurry flows, effectively preventing corrosion of the pipeline. At the same time, it ensures the strength of the pipeline, prolongs the service life of the pipeline in the limestone wet desulfurization system, improves the stability of the operation of the wet desulfurization system, and has good promotion value.

[0052] The present invention is not limited to the above-mentioned embodiments. Anyone can derive other various forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that is the same or similar to that of the present application falls within the protection scope of the present invention.

Claims

1. A corrosion-resistant pipeline, characterized in that: The invention comprises an inner tube and a composite material layer, wherein the composite material layer is prestressed and wound around the outer side of the inner tube; the composite material layer comprises glass fiber and epoxy resin, the glass fiber is impregnated with epoxy resin and the glass fiber containing epoxy resin is wound around the circumferential outer side of the inner tube; the composite material layer also comprises a curing agent, and the weight ratio of the curing agent to the epoxy resin is 1:10; the glass fiber containing epoxy resin is prestressed and wound around the outer side of the inner tube, and the prestress is not greater than 50Mpa; the glass fiber is applied with prestress wound around the inner tube in a layer-by-layer decreasing manner, and there are twelve layers of glass fiber layers wound around the outer side of the inner tube, and the prestress of the first layer of glass fiber is 45Mpa; the glass fiber is circumferentially wound around the circumferential outer side of the inner tube, and the winding angle is not greater than 15°; after the glass fiber containing epoxy resin is wound around the inner tube to form a glass fiber composite material, it is subjected to rotational curing molding, the curing temperature is 60°C, and the curing time is 120min; the volume ratio of the glass fiber to the composite material layer is not less than 80%; the thickness ratio of the inner tube to the composite material layer is 1:1.2; the thickness of the composite material layer is 3mm.

2. The corrosion-resistant pipeline according to claim 1, characterized in that: The inner tube is made of 316L stainless steel.

3. A method for forming a corrosion-resistant pipe according to any one of claims 1 to 2, characterized in that: The following steps are involved: S1, fix the inner tube on the winding device through the inner expansion mandrel, and the winding device drives the inner tube to rotate; S2, overlapping the glass fiber at the end of the inner tube, impregnating the glass fiber with epoxy resin and winding the glass fiber containing epoxy resin to the circumferential outer side of the inner tube; S3, placing the assembly formed by the inner tube and the composite material layer in a curing device for curing; S4. Remove the inner expansion mandrel.

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