A production process of a basalt fiber (CBF) double-reinforced polyethylene pipe

Abstract

The present invention discloses a production process for basalt fiber (CBF) double-reinforced polyethylene pipes, which is characterized by including the steps of plasticizing and extruding polyethylene raw materials in an extruder, shaping, and cooling to obtain a core tube layer; then, heating a thermoplastic plastic to 200°C to 250°C to melt it, adding chopped basalt fibers to the thermoplastic plastic, and stirring evenly to obtain a reinforced slurry; then cooling the reinforced slurry to 170°C to 190°C, and then passing continuous basalt fibers through the reinforced slurry so that a layer of reinforced slurry is wrapped around the outside of the continuous basalt fibers. In the present invention, continuous basalt fibers are passed through a reinforced slurry composed of a thermoplastic plastic, chopped basalt fibers, and calcium carbonate powder, so that a layer of reinforced slurry is wrapped around the outside of the continuous basalt fibers. When the continuous basalt fibers are wound around the core tube layer, a strengthening layer can be formed on the outside of the core tube layer, thereby improving the strength and stiffness of the polyethylene pipe.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline production, and specifically discloses a production process for basalt fiber (CBF) double-reinforced polyethylene pipes. Background Art

[0002] Polyethylene is a thermoplastic resin obtained by polymerization of ethylene. Due to its high strength, high temperature resistance, corrosion resistance, non-toxicity and other characteristics, it is widely used in fields such as water supply, gas, sewage and communication cables. With the gradual expansion of urban construction, polyethylene pipes will also be used in more severe environments. Therefore, people's requirements for the compressive strength of polyethylene pipes are getting higher and higher. For this reason, some technologies wind a layer of reinforcing fibers on the outer side of the inner layer of polyethylene pipes during the production of polyethylene pipes to improve the strength of the polyethylene pipes. Although the strength of the polyethylene pipes can be improved to a certain extent after simply winding a layer of reinforcing fibers, their strength and stiffness still cannot meet the requirements of some severe environments. Summary of the Invention

[0003] In order to solve the above problems, the present invention provides a production process for basalt fiber (CBF) double-reinforced polyethylene pipes with higher strength.

[0004] The object of the present invention is achieved by the following technical solutions: A production process for basalt fiber (CBF) double-reinforced polyethylene pipes includes the following steps:

[0005] Step 1: Place the polyethylene raw material in an extruder for plasticizing extrusion, shaping and cooling to obtain a core tube layer;

[0006] Step 2: Heat the thermoplastic plastic to 200°C - 250°C until it melts, then add chopped basalt fibers to the thermoplastic plastic, and stir evenly to obtain a reinforced slurry;

[0007] Step 3: Cool the reinforced slurry to 170°C - 190°C, and then pass continuous basalt fibers through the reinforced slurry so that a layer of reinforced slurry is wrapped outside the continuous basalt fibers;

[0008] Step 4: Cool the continuous basalt fibers wrapped with the reinforced slurry to 140°C - 170°C, and then wind them on the outside of the core tube layer to form a strengthening layer; the gaps between the wound continuous basalt fibers are filled with the reinforced slurry wrapped outside the continuous basalt fibers to obtain basalt double-reinforced polyethylene pipes.

[0009] Further, in Step 2, the mass ratio of the thermoplastic plastic to the chopped basalt fibers is 1:1 - 3.

[0010] The length of the chopped basalt fibers in Step 2 is 1 - 5 mm.

[0011] In Step 2, calcium carbonate powder is also added to the thermoplastic plastic, and after being stirred evenly, an enhanced slurry is obtained; wherein, the particle size of the calcium carbonate powder is between 1 μm and 20 μm, and the mass ratio of the thermoplastic plastic, chopped basalt fibers, and calcium carbonate powder is 1:1-3:0.08-0.4.

[0012] The thermoplastic plastic in Step 2 is polyethylene, polyvinyl chloride, or polypropylene.

[0013] In Step 4, the continuous basalt fibers wrapped with the enhanced slurry are spirally or reticularly wound around the core tube layer.

[0014] After Step 4, it further includes: extruding an outer protective layer outside the strengthening layer through an extruder.

[0015] Compared with the prior art, the present application has the following beneficial effects: In the present invention, continuous basalt fibers are passed through an enhanced slurry mixed with a thermoplastic plastic, chopped basalt fibers, and calcium carbonate powder, so that the outside of the continuous basalt fibers is wrapped with the enhanced slurry together. When the continuous basalt fibers are wound around the core tube layer, a strengthening layer can be formed outside the core tube layer, thereby improving the strength and stiffness of the polyethylene pipe. At the same time, the enhanced slurry wrapped outside the continuous basalt fibers can fill the winding gaps formed after the continuous basalt fibers are wound, so that a continuous strengthening layer is formed outside the core tube layer, compensating for the strength loss at the winding gaps, and therefore can further improve the strength and stiffness of the polyethylene pipe.

[0016] Some additional features of the present application can be described below. Through the following description or the understanding of the production or operation of the embodiments, some additional features of the present application are obvious to those skilled in the art. The features disclosed in the present application can be realized and achieved through the practice or use of various methods, means, and combinations of the specific embodiments described below. Detailed Embodiments

[0017] In order to enable those skilled in the art of the present technology to better understand the solution of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope of protection of the present application.

[0018] It should be noted that if the terms "first", "second", etc. are involved in the description and claims of this application, they are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances for the embodiments of this application described herein. In addition, if the terms "comprising", "having" and any variations thereof are involved, the intention is to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0019] Moreover, in addition to being used to represent orientation or positional relationships, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0020] In addition, in this application, if terms such as "installed", "set up", "provided with", "connected", "linked", "socketed", etc. are involved, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there can be internal communication between two devices, components or parts. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0021] It should be noted that, without conflict, the embodiments and features in the embodiments of this application can be combined with each other. The following will describe this application in detail with reference to the embodiments.

[0022] Embodiment 1

[0023] This embodiment discloses a production process for basalt fiber (CBF) double-reinforced polyethylene pipes, including the following steps:

[0024] First, the polyethylene raw material is placed in an extruder for plasticizing extrusion, shaping and cooling to obtain the core pipe layer.

[0025] Then, the thermoplastic is added to the hopper and heated to 200 °C to make it melt. Then, short-cut basalt fibers are added to the thermoplastic and stirred evenly to obtain the reinforced slurry. Among them, the thermoplastic is polyethylene, the length of the short-cut basalt fibers is 1 mm, and the mass ratio of the thermoplastic to the short-cut basalt fibers is 1:1.

[0026] Secondly, cool the enhanced slurry to 180°C, and then pass continuous basalt fibers through the enhanced slurry so that a layer of enhanced slurry is wrapped around the outside of the continuous basalt fibers.

[0027] Next, cool the continuous basalt fibers wrapped with the enhanced slurry to 140°C, and then wind the continuous basalt fibers wrapped with the enhanced slurry around the outside of the core tube layer in a net shape on a winding machine to form a reinforcing layer. During winding, the gaps between the wound continuous basalt fibers are filled with the enhanced slurry wrapped around the outside of the continuous basalt fibers, so that a continuous reinforcing layer is formed outside the core tube layer, compensating for the strength loss at the winding gaps, and thus further improving the strength and stiffness of the polyethylene pipe.

[0028] Finally, extrude an outer protective layer outside the reinforcing layer through an extruder, and thus a basalt double-reinforced polyethylene pipe can be obtained. Among them, the outer protective layer is made of polyethylene material.

[0029] Example 2

[0030] The production process of the basalt fiber (CBF) double-reinforced polyethylene pipe in this example includes the following steps:

[0031] First, place the polyethylene raw material in an extruder for plasticizing extrusion, shaping, and cooling to obtain a core tube layer.

[0032] Then, add the thermoplastic plastic into the feed bin, heat it to 250°C to make it melt, and then add short-cut basalt fibers to the thermoplastic plastic, and stir evenly to obtain an enhanced slurry. Among them, the thermoplastic plastic is polyethylene, the length of the short-cut basalt fibers is 5 mm, and the mass ratio of the thermoplastic plastic to the short-cut basalt fibers is 1:2.

[0033] Secondly, cool the enhanced slurry to 190°C, and then pass continuous basalt fibers through the enhanced slurry so that a layer of enhanced slurry is wrapped around the outside of the continuous basalt fibers.

[0034] Next, cool the continuous basalt fibers wrapped with the enhanced slurry to 150°C, and then wind the continuous basalt fibers wrapped with the enhanced slurry around the outside of the core tube layer in a net shape on a winding machine to form a reinforcing layer. During winding, the gaps between the wound continuous basalt fibers are filled with the enhanced slurry wrapped around the outside of the continuous basalt fibers.

[0035] Finally, extrude an outer protective layer outside the reinforcing layer through an extruder, and thus a basalt double-reinforced polyethylene pipe can be obtained. Among them, the outer protective layer is made of polyethylene material.

[0036] Example 3

[0037] The production process of the basalt fiber (CBF) double-reinforced polyethylene pipe in this example includes the following steps:

[0038] First, place the polyethylene raw material in an extruder for plasticization, extrusion, shaping, and cooling to obtain the core tube layer.

[0039] Then, add the thermoplastic plastic into the hopper, heat it to 250 °C to make it molten, and then add chopped basalt fibers and calcium carbonate powder to the thermoplastic plastic. After stirring evenly, an enhanced slurry is obtained. Among them, the thermoplastic plastic is polyethylene, the length of the chopped basalt fibers is 3 mm, the mass ratio of the thermoplastic plastic to the chopped basalt fibers is 1:2:0.3, and the particle size of the calcium carbonate powder is 5 μm.

[0040] Secondly, cool the enhanced slurry to 180 °C, and then pass the continuous basalt fiber through the enhanced slurry so that a layer of enhanced slurry is wrapped outside the continuous basalt fiber.

[0041] Next, cool the continuous basalt fiber wrapped with the enhanced slurry to 150 °C, and then wind the continuous basalt fiber wrapped with the enhanced slurry in a net shape on the outside of the core tube layer on a winding machine to form a reinforcing layer. During winding, the gaps between the wound continuous basalt fibers are filled with the enhanced slurry wrapped outside the continuous basalt fiber.

[0042] Finally, extrude an outer protective layer outside the reinforcing layer through an extruder, and thus a basalt double-reinforced polyethylene pipe can be obtained. Among them, the outer protective layer is made of polyethylene material.

[0043] Comparative Example 1

[0044] The difference between the production process in this comparative example and that in Example 3 is that in this comparative example, the continuous basalt fiber is not wrapped with the enhanced slurry. During winding, the outer surface of the core tube layer is heated and softened, and then the continuous basalt fiber is wound on the core tube layer.

[0045] Comparative Example 2

[0046] Place the polyethylene raw material in an extruder for plasticization, extrusion, shaping, and cooling to obtain the core tube layer.

[0047] Then, add the thermoplastic plastic into the hopper, heat it to 250 °C to make it molten, and then add chopped basalt fibers and calcium carbonate powder to the thermoplastic plastic. After stirring evenly, an enhanced slurry is obtained. Among them, the thermoplastic plastic is polyethylene, the length of the chopped basalt fibers is 3 mm, the mass ratio of the thermoplastic plastic to the chopped basalt fibers is 1:4:0.5, and the particle size of the calcium carbonate powder is 25 μm.

[0048] Secondly, cool the enhanced slurry to 180 °C, and then pass the continuous basalt fiber through the enhanced slurry so that a layer of enhanced slurry is wrapped outside the continuous basalt fiber.

[0049] Next, cool the continuous basalt fibers wrapped with the reinforcing slurry to 150°C, and then wind the continuous basalt fibers wrapped with the reinforcing slurry in a net-like manner on the outer side of the core tube layer to form a reinforcing layer. During winding, the gaps between the wound continuous basalt fibers are filled with the reinforcing slurry wrapped on the outer side of the continuous basalt fibers.

[0050] Finally, extrude an outer protective layer on the outer side of the reinforcing layer through an extruder, and thus a polyethylene pipe can be obtained. Among them, the outer protective layer is made of polyethylene material.

[0051] Tensile strength and ring stiffness tests were carried out on the polyethylene pipes prepared by the production processes in the above Examples 1 to 3 and Comparative Examples 1 and 2 under the same environment, and the test results are as follows:

[0052] Tensile strength (MPa) Ring stiffness (KPa) Example 1 35.3 7.03 Example 2 35.8 7.01 Example 3 36.8 8.15 Comparative Example 1 30.6 5.02 Comparative Example 2 33.9 6.84

[0053] It can be seen from the above test results that in Examples 1 and 2, the continuous basalt fibers are wrapped with a reinforcing slurry composed of a mixture of thermoplastic plastics and chopped basalt fibers. After the continuous basalt fibers are wound on the core tube layer, the polyethylene pipe can have strong tensile strength and ring stiffness. Calcium carbonate powder is added to the reinforcing slurry in Example 3, so the polyethylene pipe produced has the best tensile strength and ring stiffness. The continuous basalt fibers in Comparative Example 1 are not wrapped with a reinforcing slurry, and the polyethylene pipe produced has poor tensile strength and ring stiffness. Although the continuous basalt fibers in Comparative Example 2 are wrapped with a reinforcing slurry composed of a mixture of thermoplastic plastics, chopped basalt fibers and calcium carbonate powder, due to the too high proportion of chopped basalt fibers and calcium carbonate powder, which affects the adhesion of thermoplastic plastics, the tensile strength and ring stiffness of the polyethylene pipe produced are affected.

[0054] It should be noted that all the features disclosed in this specification, or all the steps in the disclosed methods or processes, except for mutually exclusive features and / or steps, can be combined in any way.

[0055] In addition, the above specific embodiments are exemplary. Those skilled in the art can come up with various solutions inspired by the disclosed content of the present invention, and these solutions also belong to the disclosed scope of the present invention and fall within the protection scope of the present invention. Those skilled in the art should understand that the descriptions in the specification of the present invention are all illustrative and do not constitute a limitation on the claims. The protection scope of the present invention is defined by the claims and their equivalents.

Claims

1. A production process for basalt fiber (CBF) double-reinforced polyethylene pipe, characterized in that: The following steps are involved: Step 1: Plasticize, extrude, shape, and cool the polyethylene raw material in an extruder to obtain a core tube layer; Step 2: After the thermoplastic is heated to 200°C to 250°C and melted, short-cut basalt fibers are added to the thermoplastic and stirred to obtain a reinforced slurry; Step 3: Cool the reinforcement slurry to 170°C to 190°C, then pass the continuous basalt fiber through the reinforcement slurry so that the continuous basalt fiber is wrapped with a layer of reinforcement slurry; Step 4: After cooling the continuous basalt fiber wrapped with the reinforcing slurry to 140°C to 170°C, it is wound around the outside of the core tube layer to form a reinforcement layer; the gaps between the wound continuous basalt fibers are filled with the reinforcing slurry wrapped around the outside of the continuous basalt fibers to produce a basalt double-reinforced polyethylene pipe; In step 2, the mass ratio of the thermoplastic to the chopped basalt fiber is 1:1 to 3; The thermoplastic in step 2 is polyethylene, polyvinyl chloride or polypropylene.

2. The production process of basalt fiber (CBF) double-reinforced polyethylene pipe according to claim 1, characterized in that: The length of the chopped basalt fibers in step 2 is 1 to 5 mm.

3. The production process of basalt fiber (CBF) double-reinforced polyethylene pipe according to claim 1, characterized in that: In step 2, calcium carbonate powder is further added to the thermoplastic plastic and stirred evenly to obtain a reinforcing slurry; wherein the particle size of the calcium carbonate powder is between 1 μm and 20 μm, and the mass ratio of the thermoplastic plastic, the chopped basalt fiber and the calcium carbonate powder is 1:1-3:0.08-0.

4.

4. The production process of basalt fiber (CBF) double-reinforced polyethylene pipe according to claim 1, characterized in that: In step 4, the continuous basalt fibers wrapped with the reinforcing slurry are wound on the core tube layer in a spiral or mesh shape.

5. The production process of basalt fiber (CBF) double-reinforced polyethylene pipe according to claim 1, characterized in that: After step 4, the method further includes: extruding an outer protective layer on the outside of the reinforcement layer through an extruder.