Composite pipe preparation method, steel strip, composite steel strip and composite pipe

Abstract

The present invention discloses a method for preparing a composite pipe, which comprises the following steps: ① drilling holes on a steel belt; ② surface cleaning; ③ heating the steel belt with a high-frequency induction machine; ④ applying a hot-melt adhesive to the upper and lower surfaces of the steel belt and the holes. Compared with the existing ones, the composite pipe polyethylene of the present invention can be well integrated with the steel belt, so that the bearing capacity of the pipe is stronger and the service life is longer. The steel belt coated in the polyethylene is not easy to rust, and the compatibility and adhesion between the steel belt and the polyethylene are stronger; it can effectively avoid the false adhesion between the steel belt and the polyethylene caused by the conventional steel belt polyethylene composite pipe, resulting in the separation and delamination of the steel belt and the polyethylene, thereby causing the quality accident caused by the rust of the steel belt.

Description

Technical Field

[0001] The invention relates to a method for preparing a composite pipeline, a steel belt for the composite pipeline, a composite steel belt and a composite pipeline. Background Art

[0002] Threaded corrugated pipes are usually divided into three layers, the inner layer is a continuous solid wall inner pipe, the middle layer is an annular steel belt reinforcement, and the outer layer is a HDPE outer layer. The annular steel belt reinforcement in the prior art uses a steel belt that is directly coated with plastic and then bent into a spiral shape to directly produce a pipe. On the one hand, this process causes insufficient adhesion between the steel belt and the inner and outer layers, and it is easy to debond during use, resulting in the steel belt and the inner and outer layers not being able to achieve a coordinated force state. On the other hand, the steel belt rusts, resulting in a loose bond between the steel belt and the inner and outer layers. Moreover, false adhesion may occur between the steel belt and the inner and outer polymer materials, resulting in delamination of the steel belt and the inner and outer layers, thereby rusting the steel belt and forming quality defects. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing a composite pipe.

[0004] The technical solution is: a method for preparing a composite pipe, the method comprising the following steps:

[0005] ① Punch holes on the steel belt;

[0006] ②Surface cleaning;

[0007] ③ Use a high-frequency induction machine to heat the steel strip;

[0008] ④Apply the hot melt adhesive to the upper and lower surfaces of the steel belt and the holes

[0009] The invention also provides a steel belt for the composite pipeline.

[0010] The technical solution is: a steel belt for composite pipelines, comprising a steel belt body, on which a plurality of holes are distributed, and the plurality of holes are distributed in a rhombus shape.

[0011] The invention also provides a composite steel belt for the composite pipeline.

[0012] The technical solution is: a composite steel belt for a composite pipe, comprising a steel belt layer, on which a plurality of holes are distributed, the composite steel belt for the composite pipe also comprising an upper resin adhesive layer, a lower resin adhesive layer and a hole wall resin adhesive layer, the upper resin adhesive layer is tightly adhered to the upper surface of the steel belt layer, the lower resin adhesive layer is tightly adhered to the lower surface of the steel belt layer, and the hole wall resin adhesive layer is tightly adhered to the hole walls of a plurality of holes.

[0013] Preferably, the plurality of holes are distributed in a diamond shape.

[0014] The invention also provides a composite pipe.

[0015] The technical solution is: a composite pipe, including a pipe wall, which surrounds a pipe cavity, the pipe wall includes a polymer inner layer and a composite layer composed of a plurality of wave crests and a plurality of wave troughs which are alternately distributed, the plurality of wave troughs are attached to the outer surface of the inner layer, each wave crest includes a lower wave crest adhesive layer, a wave crest steel belt layer, an upper wave crest adhesive layer, a wave crest mixed layer and a wave crest polymer outer layer, each wave trough includes a lower wave trough mixed layer, a lower wave trough adhesive layer, a wave trough steel belt layer, an upper wave trough adhesive layer, a wave trough mixed layer and a wave trough polymer outer layer, the lower wave crest adhesive layer, the wave crest steel belt layer, the upper wave crest adhesive layer, the wave crest mixed layer and the wave crest polymer outer layer are arranged in sequence from bottom to top, and the wave trough The lower mixed layer, the trough lower adhesive layer, the trough steel belt layer, the trough upper adhesive layer, the trough upper mixed layer and the trough polymer outer layer are arranged sequentially from bottom to top, the trough steel belt layer is connected to the peak steel belt layer as a whole, the peak polymer outer layer is connected to the trough polymer outer layer as a whole, the peak steel belt layer is provided with peak plug holes, the trough steel belt layer is provided with trough plug holes, the peak plug holes are filled with the same material as the peak polymer outer layer, the trough plug holes are filled with the same material as the trough polymer outer layer and the same material as the peak polymer outer layer, wherein the same material as the peak polymer outer layer is on the top, and the same material as the trough polymer outer layer is on the bottom.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention can increase the composite pipe material of steel belt and polyethylene fusion. The polyethylene of the composite pipe material can be well fused with the steel belt, so that the bearing capacity of the pipeline is stronger and the service life is longer. The steel belt coated in the polyethylene is not easy to rust, and the compatibility and adhesion between the steel belt and the polyethylene are stronger. The false adhesion between the steel belt and the polyethylene caused by the conventional steel belt and polyethylene composite pipe can be effectively avoided, resulting in the separation and delamination of the steel belt and the polyethylene, thereby causing the quality accidents caused by the rust of the steel belt. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the steel belt for the composite pipeline of the present invention;

[0019] Figure 2 It is a schematic diagram of the structure of the composite steel strip for the composite pipeline of the present invention;

[0020] Figure 3 It is a three-dimensional schematic diagram of the invented composite pipeline;

[0021] Figure 4 It is a schematic cross-sectional view of the present invention;

[0022] Figure 5 yes Figure 4 A magnified image;

[0023] Figure 6 yes Figure 4 Enlarged view of point B. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the accompanying drawings.

[0025] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "front", "back" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, or the positions or positional relationships in which the invented product is usually placed when used, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. .

[0026] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] Example 1

[0029] like Figure 1 As shown, a steel belt for composite pipes includes a steel belt body 1, on which a plurality of holes 11 are distributed, and the plurality of holes 11 are distributed in a rhombus shape.

[0030] The steel strip for the composite pipe is manufactured by the following steps:

[0031] ① Clean the surface of the steel strip body 1.

[0032] ② Punch a plurality of holes 11 on the steel strip body 1 by a die-casting punch, wherein the plurality of holes 11 are distributed in a diamond shape.

[0033] Example 2

[0034] like Figure 2As shown, a composite steel belt for a composite pipe includes a steel belt layer 1, on which a plurality of holes 11 are distributed, and further includes an upper resin adhesive layer 3, a lower resin adhesive layer 4 and a hole wall resin adhesive layer 5. The upper resin adhesive layer 3 is tightly adhered to the upper surface of the steel belt layer 1, the lower resin adhesive layer 4 is tightly adhered to the lower surface of the steel belt layer 1, and the hole wall resin adhesive layer 5 is tightly adhered to the hole walls of the plurality of holes 11.

[0035] It is further explained that the plurality of holes 11 are distributed in a rhombus shape.

[0036] The composite steel strip for the composite pipe is manufactured by the following steps:

[0037] ① The steel strip body 1 is punched with a plurality of holes 11 by a die-casting punch, and the plurality of holes 11 are distributed in a rhombus shape.

[0038] ② The surface of the punched steel strip body 1 is cleaned to bake off impurities and oxides on the surface of the steel strip body 1.

[0039] ③ Use a high-frequency induction machine to heat the surface of the steel strip body 1. The purpose of heating is to make the adhesive better bonded to the steel strip body 1.

[0040] ④ Apply the hot-melt resin adhesive to the upper and lower surfaces of the steel belt body 1. The purpose is to use the strong fluidity of the resin adhesive to pass through the hole 11, so that the upper and lower layers of the adhesive are connected to each other through the holes, fully covering the steel belt to prevent the steel belt and the adhesive from being separated and layered, so as to achieve a better bonding effect, and at the same time isolate the steel belt from the air to prevent oxidation of the steel belt.

[0041] Example 3

[0042] like Figure 3-6As shown, a composite pipe comprises a pipe wall 6, which surrounds a pipe cavity 5, and the pipe wall 6 comprises a polymer inner layer 21 and a composite layer composed of a plurality of wave crests 1 and a plurality of wave troughs 2 which are alternately distributed, and the plurality of wave troughs 2 are attached to the outer surface of the inner layer 21, each wave crest 1 comprises a lower wave crest adhesive layer 62, a wave crest steel belt layer 12, an upper wave crest adhesive layer 52, a wave crest mixed layer 42 and a wave crest polymer outer layer 32, and each wave trough 2 comprises a lower wave trough mixed layer 7, a lower wave trough adhesive layer 61, a wave trough steel belt layer 11, an upper wave trough adhesive layer 51, an upper wave trough mixed layer 41 and a wave trough polymer outer layer 31, and the lower wave crest adhesive layer 62, the wave crest steel belt layer 12, the upper wave crest adhesive layer 52, the wave crest mixed layer 42 and the wave crest polymer outer layer 32 are arranged sequentially from bottom to top, and the wave trough The lower mixed layer 7, the trough lower adhesive layer 61, the trough steel belt layer 11, the trough upper adhesive layer 51, the trough upper mixed layer 41 and the trough polymer outer layer 31 are arranged sequentially from bottom to top, the trough steel belt layer 11 is connected to the peak steel belt layer 12 as a whole, the peak polymer outer layer 32 is connected to the trough polymer outer layer 31 as a whole, the peak steel belt layer 12 is provided with a peak plug hole 3, the trough steel belt layer 11 is provided with a trough plug hole 4, the peak plug hole 3 is filled with the same material as the peak polymer outer layer 32, the trough plug hole 4 is filled with the same material as the trough polymer outer layer 31 and the same material as the peak polymer outer layer 32, wherein the same material as the peak polymer outer layer 32 is on the top, and the same material as the trough polymer outer layer 31 is on the bottom.

[0043] The polymer inner layer 21 is a polyethylene inner layer made of polyethylene.

[0044] The peak polymer outer layer 32 is a polyethylene peak polymer outer layer made of polyethylene, and the trough polymer outer layer 31 is a polyethylene trough polymer outer layer.

[0045] The adhesive layer 51 on the trough, the adhesive layer 61 under the trough, the adhesive layer 52 on the peak, and the adhesive layer 62 under the peak are all formed of the same adhesive.

[0046] The peak mixing layer 42 is composed of the same material and adhesive as the peak polymer outer layer 32, the trough upper mixing layer 41 is composed of the same material and adhesive as the trough polymer outer layer 31, and the trough lower mixing layer 7 is composed of the same material and adhesive as the polymer inner layer 21.

[0047] The above composite pipe is made by the following steps:

[0048] ① The steel strip body is punched with several holes through a die-casting punch.

[0049] ② The surface of the steel strip body after punching is cleaned to bake off the impurities and oxides on the surface of the steel strip body.

[0050] ③ Use a high-frequency induction machine to heat the surface of the steel strip body. The purpose of heating is to make the adhesive better bonded to the steel strip body and to make the coating more uniform during coating.

[0051] ④ Apply the hot-melt resin adhesive to the upper and lower surfaces of the steel belt body. The purpose is to use the strong fluidity of the resin adhesive to pass through the holes, so that the upper and lower layers of the adhesive are connected to each other through the holes, fully covering the steel belt to prevent the steel belt and the adhesive from being separated and layered, so as to achieve a better bonding effect, and at the same time isolate the steel belt from the air to prevent the steel belt from oxidation.

[0052] The subsequent steps are to make the spiral corrugated pipe according to the conventional process. In the present invention, the steel strip body is completely isolated from the air by first punching holes in the steel strip body and then coating it with hot-melt resin adhesive after heating. Then, when the inner and outer layers are pressed together with the steel strip body to form a threaded pipe, the resin adhesive is adhered to the hole wall and the corresponding positions where the upper and lower surfaces of the steel strip body are combined with the outer layer and the inner layer are coated with resin adhesive, so that the adhesive and the inner and outer layer polymer materials are more likely to penetrate each other, especially at the wave crest, under the adsorption of the adhesive, the outer layer polymer penetrates into the hole, and the peak is flat. At the wave trough, under the adsorption of the adhesive, the outer and inner layer polymers penetrate each other and firmly form a structure. When the outer layer and the inner layer are made of the same polymer material, the best bonding effect is achieved.

[0053] Example 4

[0054] Compared with Example 3, this embodiment is the same as Example 3 except for the different preparation method.

[0055] In this embodiment, the composite pipe is made by the following steps:

[0056] ① The steel strip body is punched with a plurality of holes through a die-casting punch, and the holes are distributed in a rhombus shape. The purpose of the rhombus distribution is to enhance the compatibility of the binder with the outer and inner polymer materials during subsequent pressing (by adjusting the stress distribution) and to improve the bonding effect after pressing.

[0057] ② Clean the surface of the steel belt body after punching.

[0058] ③ Use a high-frequency induction machine to heat the surface of the steel strip.

[0059] ④ Apply the hot-melt resin adhesive to the upper and lower surfaces of the steel belt body.

[0060] ⑤Cut the head end of the steel strip into a dovetail shape.

[0061] ⑥ Start the forming device and bending mechanism, run at a speed of 1:1.4, feed the steel strip into the forming device, pass through the vertical roller → flattening roller → vertical roller → forming concave-convex roller → bending forming mechanism, adjust and bend the second set of rollers to make the surface of the plastic-coated steel strip ring smooth and flat.

[0062] ⑦ Adjust the third set of bending rollers to ensure that the diameter of the steel strip after rolling into a round shape is consistent with customer requirements.

[0063] ⑧ While sending the adjusted formed steel belt to the feeding device, start the feeding motor. Let the formed plastic-coated steel belt run on the feeding frame, adjust the relative position of the feeding device and ensure that the formed steel belt runs smoothly on it.

[0064] ⑨ Send the round end of the formed steel strip to the upper pressing wheel, and adjust the roller guide device. And loosen the upper and lower pressing wheels.

[0065] ⑩ Start the mold temperature controller first, set the water temperature of the mold temperature controller to about 45℃ (the temperature setting varies in winter and summer); turn on the oven at the same time, when the steel belt is preheated to the appropriate temperature (about 100℃), start the first extruder to extrude the chip (inner layer), start the second extruder to extrude the outer sheet (polymer outer layer), adjust the speed to the process value, press the upper and lower pressing wheels, and then start the forming, bending, and feeding motors, operate according to the corresponding ratio, and at the same time pass the steel belt through the upper pressing wheel, so that the steel belt moves synchronously with the chip and outer sheet, and then guide it to the lower pressing roller. Turn on the outer sheet blowing device and adjust the side pressing wheel to ensure that the shape of the outer sheet and the steel belt is consistent.

[0066] The composite tube made of ⑩ is cut into the length required by the customer.

[0067] The composite pipe was tested for performance, and the test results are shown in Table 1:

[0068] Example 5

[0069] Compared with Example 3, this embodiment is the same as Example 3 except that the hole distribution is different.

[0070] A number of holes are distributed in a rhombus shape. The purpose of the rhombus distribution is to enhance the compatibility of the adhesive with the outer layer and the inner layer polymer material during subsequent pressing (by adjusting the stress distribution) and to improve the bonding effect after pressing.

[0071] The composite pipe was tested for performance, and the test results are shown in Table 1:

[0072] Example 6

[0073] The composite pipe of this embodiment is made by the following steps:

[0074] ① The steel strip body is punched with several holes through a die-casting punch.

[0075] ② Clean the surface of the steel belt body after punching.

[0076] After cleaning, the spiral corrugated pipe is made into a spiral corrugated pipe according to a conventional process without coating an adhesive.

[0077] The performance of the manufactured spiral bellows was tested, and the test results are shown in Table 1:

[0078] Table 1

[0079]

[0080] This specification describes examples of embodiments of the present invention, and it is not intended that these embodiments illustrate and describe all possible forms of the present invention. It should be understood that the embodiments in the specification can be implemented in a variety of alternative forms. The drawings need not be drawn to scale; some features can be enlarged or reduced to show the details of specific components. The specific structural and functional details disclosed should not be interpreted as limiting, but are merely representative bases for teaching those skilled in the art to implement the present invention in various forms. It should be understood by those skilled in the art that the multiple features illustrated and described with reference to any of the figures can be combined with the features illustrated in one or more other figures to form embodiments that are not explicitly illustrated or described. The illustrated combined features provide representative embodiments for typical applications. However, various combinations and variations of features consistent with the teachings of the present invention can be used for specific applications or implementations as needed.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a composite pipe, the method comprising the following steps: ① Punch holes on the steel strip using a die-casting punch. The holes are distributed in a diamond shape, with two adjacent rows of holes or two adjacent columns of holes staggered; ②Surface cleaning; ③ Use a high-frequency induction machine to heat the steel strip; ④Apply the hot-melt adhesive to the upper and lower surfaces of the steel belt and inside the holes; ⑤Cut the head end of the steel strip into a dovetail shape; ⑥ Start the forming device and bending mechanism, run at a speed of 1:1.4, feed the steel strip into the forming device, pass through the vertical roller → flattening roller → vertical roller → forming concave-convex roller → bending forming mechanism, adjust and bend the second set of rollers to make the surface of the plastic-coated steel strip ring smooth and flat; ⑦ Adjust the third set of bending rollers to ensure that the diameter of the steel strip after rolling into a round shape is consistent with the customer's requirements; ⑧ While sending the adjusted formed steel belt to the feeding device, start the feeding motor; let the formed plastic-coated steel belt run on the feeding frame, adjust the relative position of the feeding device, and ensure that the formed steel belt runs smoothly on it; ⑨ Send the round end of the formed steel strip to the upper pressing wheel, and adjust the roller guide device; and loosen the upper and lower pressing wheels; ⑩First start the mold temperature controller and set the water temperature of the mold temperature controller to about 45°C; at the same time, turn on the oven. When the steel belt is preheated to the appropriate temperature, start the first extruder to extrude the inner layer, start the second extruder to extrude the polymer outer layer, adjust the speed to the process value, press the upper and lower pressing wheels, and then start the forming, bending, and feeding motors, and run them according to the corresponding ratios. At the same time, pass the steel belt through the upper pressing wheel so that the steel belt moves synchronously with the chip and outer sheet, and then guide it to the lower pressing roller; Turn on the outer sheet blowing device and adjust the edge pressing wheel to ensure that the shapes of the outer sheet and the steel belt are consistent; The composite pipe comprises a pipe wall, which surrounds a pipe cavity. The pipe wall comprises a polymer inner layer and a composite layer composed of a plurality of wave crests and a plurality of wave troughs distributed alternately. The plurality of wave troughs are attached to the outer surface of the inner layer. Each wave crest comprises a lower wave crest adhesive layer, a wave crest steel belt layer, an upper wave crest adhesive layer, a wave crest mixed layer and a wave crest polymer outer layer. Each wave trough comprises a lower wave trough mixed layer, a lower wave trough adhesive layer, a wave trough steel belt layer, an upper wave trough adhesive layer, a wave trough mixed layer and a wave trough polymer outer layer. The lower wave crest adhesive layer, the wave crest steel belt layer, the upper wave crest adhesive layer, the wave crest mixed layer and the wave crest polymer outer layer are arranged in sequence from bottom to top. The lower wave trough mixed layer, the wave crest steel belt layer, the upper wave crest adhesive layer, the wave crest mixed layer and the wave crest polymer outer layer are arranged in sequence from bottom to top. The lower valley adhesive layer, the trough steel belt layer, the upper trough adhesive layer, the upper trough mixed layer and the trough polymer outer layer are arranged sequentially from bottom to top, the trough steel belt layer is connected to the peak steel belt layer as a whole, the peak polymer outer layer is connected to the trough polymer outer layer as a whole, the peak steel belt layer is provided with a peak plug hole, the trough steel belt layer is provided with a trough plug hole, the peak plug hole is filled with the same material as the peak polymer outer layer, the trough plug hole is filled with the same material as the trough polymer outer layer and the same material as the peak polymer outer layer, wherein the same material as the peak polymer outer layer is on the top, and the same material as the trough polymer outer layer is on the bottom.

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