A kind of FRP thin-walled electric pole and its manufacturing method

Abstract

The invention discloses an FRP thin-walled pole and a manufacturing method thereof. The FRP thin-walled pole comprises a pole body. The pole body is in the shape of a truncated cone or a regular prism that is gradually thickened from top to bottom and hollow inside. The wall thickness of the pole body gradually increases from top to bottom. The pole body is formed by winding multiple layers of FRP material. A top end cap of the pole body is arranged. The FRP thin-walled pole is prepared by a winding process. The pole is designed to be a hollow thin-walled structure with a wall thickness of 2-15 mm. The pole has simple stress distribution, small internal stress, high strength, an integrated structure and light weight. The pole has a simple construction process, is not easy to rust, has a long service life, and meets various requirements for power transmission.

Description

Technical Field

[0001] The present invention relates to the technical field of power transmission poles, communication antenna poles and cable pole towers, and in particular to an FRP thin-wall pole and a manufacturing method thereof. Background Art

[0002] Traditional electric poles or cable towers generally use wooden poles, cement poles and truss iron towers. Wooden electric poles have been used for more than 200 years, but due to limited resources, insufficient height and non-straight materials, they cannot meet the needs of military and national economy. Later, cement poles were used instead, which are actually reinforced prestressed concrete poles. The disadvantage is that they are heavy. At the same time, because they are integrated structures, they need to be transported by large vehicles and loaded and unloaded and installed by cranes. Therefore, they can only be arranged along the winding road and cannot cross fields, rivers and mountains in a straight line. The iron tower is composed of heavier steel and is a detachable structure. It can be transported to the site by hand and assembled into the designed truss. Therefore, the iron tower line can go straight over mountains and fields without being arranged along the road. It can also cross rivers in a straight line without the help of highway bridges. However, the iron tower also needs a secondary transportation process from unloading from the car to the site by manpower, and the construction safety is not guaranteed. On the other hand, the steel structure is easy to rust, and the service life is threatened by rust, which increases the operating cost of the power transmission system and the communication system.

[0003] Fiber-reinforced composite materials (FiberReinforcedPolymer, referred to as FRP), the traditional name is glass fiber reinforced plastic, which is a composite material with glass fiber and its products (glass cloth, tape, felt, yarn, etc.) as reinforcing materials and synthetic resin as matrix material. Although single glass fiber has high strength, the fibers are loose and can only withstand tension, but cannot withstand bending, shearing and compressive stress. It is also not easy to make a fixed geometric shape. It is a soft body. If they are bonded together with synthetic resin, they can be made into various hard products with fixed shapes, which can withstand both tensile stress and bending, compression and shear stress. This constitutes a glass fiber reinforced plastic matrix composite material, which has the same strength as steel, contains glass components, and has the same color, shape, corrosion resistance, electrical insulation, heat insulation and other properties as glass, like glass, so it is also called "glass fiber reinforced plastic". The meaning of glass fiber reinforced plastic refers to reinforced plastic with glass fiber as reinforcing material and synthetic resin as binder, which is called glass fiber reinforced plastic abroad. With the development of FRP industry, as a reinforcing material for plastic base, it has expanded from glass fiber to carbon fiber, boron fiber, aramid fiber, alumina fiber and silicon carbide fiber. The reinforced plastics made of these new fibers have the performance characteristics of light weight, high strength, corrosion resistance, good durability and convenient construction.

[0004] The present invention proposes an FRP thin-walled electric pole and a manufacturing method thereof. The electric pole is made of FRP material through a winding molding process, has an integrated structure and is light in weight, can be carried on shoulders to the site, and thus the transportation route can be in a straight line without having to detour along the road. The electric pole has a simple construction process, is not easy to rust, has a long service life, and has high strength. The electric pole is designed to be a hollow thin-walled structure with a simple stress distribution and small internal stress. Compared with a thick-walled structure (above 15 mm), it can give full play to the advantages of the FRP material and can be made 12 meters or even 15 meters high without bending or shaking, thus meeting various requirements for power transmission. Summary of the invention

[0005] The purpose of the present invention is to provide an FRP thin-walled electric pole and a manufacturing method thereof, so as to solve the problems of existing electric poles or cable towers being heavy, inconvenient to transport and install, not corrosion-resistant, having large internal stress, low strength, short service life and high economic cost.

[0006] To achieve the above-mentioned purpose, the technical solution of the present invention is as follows: the FRP thin-walled pole includes a pole body, and the pole body as a whole is a truncated cone or a regular prism shape that gradually thickens from top to bottom and is hollow inside. The wall thickness of the pole body gradually increases from top to bottom. The pole body is formed by winding multiple layers of FRP material, and a top end cap is set for the pole body.

[0007] Preferably, at least one layer of reinforcing ribs is provided inside the pole body.

[0008] Preferably, the reinforcing rib is in a cross shape, a crisscross shape or a snowflake shape.

[0009] Preferably, a flange is provided at the bottom end of the pole body, and a plurality of bolt mounting holes are provided on the flange.

[0010] Preferably, the flange is integrally formed by winding the bottom of the pole body with FRP material or the flange is bonded to the bottom of the pole body with resin glue.

[0011] Preferably, a plurality of groups of ribs are provided on the flange, and the ribs are bonded to the pole body by resin glue.

[0012] Preferably, when the pole body is in the shape of a regular prism as a whole, the cross-sectional shape of the pole body is a regular pentagon, a regular hexagon or a regular octagon.

[0013] Preferably, the wall thickness of the pole body is 2-15 mm.

[0014] The present invention also proposes a method for manufacturing an FRP thin-walled pole, wherein the FRP thin-walled pole is prepared by a winding process, and the manufacturing method comprises the following steps:

[0015] Prepare a resin glue solution, wherein the resin glue solution contains a curing agent, and store the resin glue solution containing the curing agent in a dipping tank;

[0016] The high-strength continuous fiber is firstly soaked in resin glue through a dipping tank, and then the excess resin glue is removed by pre-extrusion through an extrusion device, so as to ensure that the weight percentage of the resin glue in the prepared FRP thin-walled pole is 15-50%, and the weight percentage of the high-strength continuous fiber is 50%-85%;

[0017] The high-strength continuous fiber impregnated with resin glue is pulled and wound onto a core mold pre-coated with a release agent by a yarn drawing arm or a yarn drawing vehicle. The core mold is installed on a rotating shaft and rotates continuously driven by the rotating shaft. The winding direction of the high-strength continuous fiber forms an angle of 45° with the axis of the core mold. The yarn drawing arm or the yarn drawing vehicle reciprocates in a direction parallel to the rotating shaft to achieve bidirectional traction of the high-strength continuous fiber in the winding direction and the forward direction.

[0018] The appropriate running speed of the yarn drawing arm or yarn drawing vehicle is controlled by computer programming to ensure uniform yarn distribution. At the same time, the yarn drawing arm or yarn drawing vehicle is set to have different running speeds during each reciprocating motion to achieve an uneven thickness structure of the FRP thin-walled pole with gradually increasing wall thickness from top to bottom. The wall thickness of the prepared FRP thin-walled pole is 2-15mm;

[0019] The wound core mold is placed in a horizontal oven for curing at a temperature of 110°C-170°C. After curing, the core mold is demoulded and taken out to obtain a FRP thin-walled pole.

[0020] Preferably, the manufacturing method also includes: before the core mold is cured after the winding is completed, the yarn pulling arm or the yarn pulling vehicle is controlled to stop at the bottom position of the FRP thin-walled pole, the core mold continues to rotate, and the high-strength continuous fiber impregnated with resin glue is wound at the bottom of the FRP thin-walled pole in multiple layers to a certain thickness to obtain a flange, or the flange made by another winding process is bonded to the bottom of the FRP thin-walled pole with resin glue, and finally the FRP thin-walled pole and the flange connected to the bottom are cured together.

[0021] The present invention has the following advantages:

[0022] The FRP thin-walled pole of the present invention adopts FRP material to form an integrated hollow structure through a winding molding process. It has the characteristics of high strength, strong wind resistance, not easy to bend and shake, light weight, and can be carried manually. It can cross fields, mountain valleys, and rivers in a straight line without being arranged along the winding road. It can not only be transported by manpower, but also be installed manually, which improves the construction safety of the project and reduces the cost of the project. During installation, it can be directly buried in the soil or connected to the base with a flange, which is simple to construct. It has excellent properties such as strong corrosion resistance and long aging resistance, which prolongs the service life of the pole, reduces the rearrangement, detection, and debugging procedures of power (communication) lines caused by replacing the pole, and reduces the maintenance cost in later operations. Since the pole generally bears a large bending moment and a large stress, the pole of the present invention has a wall thickness of 2-15mm and is designed as a thin-walled structure, which has the advantages of uniform stress distribution, reasonable force, and avoidance of internal stress. It also has good insulation. Compared with the iron tower, it reduces eddy current loss and the influence of the iron tower eddy current on the power system, meeting various requirements for power transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of an FRP thin-walled pole according to Example 1 of the present invention.

[0024] Figure 2 This is a schematic structural diagram of an FRP thin-wall pole flange according to Example 1 of the present invention.

[0025] Figure 3 This is a schematic diagram of a winding process for an FRP thin-walled pole according to Example 1 of the present invention.

[0026] Figure 4 This is a schematic structural diagram of an FRP thin-wall pole reinforcement rib according to Example 2 of the present invention. DETAILED DESCRIPTION

[0027] The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0028] Example 1

[0029] like Figure 1 As shown, an FRP thin-walled pole proposed in this embodiment includes a pole body 1. The pole body 1 is in the shape of a truncated cone or a regular prism that gradually thickens from top to bottom and is hollow inside. When the pole body 1 is in the shape of a regular prism, the cross-sectional shape of the pole body 1 may be a regular pentagon, a regular hexagon, a regular octagon or other regular polygons. In this embodiment, the pole body 1 is in the shape of a truncated cone, and the wall thickness of the pole body 1 gradually increases from top to bottom. The wall thickness of the pole body 1 in this embodiment is 2-15mm, with about 5mm being the best. The pole body 1 is formed by winding multiple layers of FRP material, and a top end cap is provided on the pole body 1 to prevent debris from entering the hollow part.

[0030] The FRP thin-walled pole of this embodiment can be 12-15 meters high. For the convenience of installation, the pole body 1 can be directly buried in the soil. The 15-meter pole body needs to be buried at a depth of 2.5 meters, and the 12-meter pole body needs to be buried at a depth of 1.5 meters. A flange 2 can also be provided at the bottom end of the pole body 1. Figure 2 As shown, a plurality of bolt mounting holes are arranged on the flange 2. The flange 2 is integrally formed by winding FRP material on the bottom of the pole body 1 or the pre-made flange 2 is bonded to the bottom of the pole body 1 by resin glue. A plurality of groups of ribs 21 can be arranged on the flange 2. The ribs 21 and the pole body 1 can be bonded by resin glue. The pole is fixed by fixing the flange to the concrete base.

[0031] A FRP thin-walled pole in this embodiment is prepared by a winding process, such as Figure 3 As shown, any medium or large winding equipment can complete the winding process. The core mold can be made of non-metal (wood or plastic), or a steel mold can be made by a mold factory. It has a certain degree of designability. The truncated cone or right prism shape of the pole body and its taper are determined by the core mold 8.

[0032] The manufacturing method of the FRP thin-walled pole comprises the following steps:

[0033] Prepare resin glue, which contains resin matrix, curing agent, initiator, accelerator, etc., and also includes anti-ultraviolet and anti-aging additives. The proportion of each component can be prepared according to the raw material instructions. For example, if the resin matrix is ​​polyester, the typical formula is (by weight): polyester matrix 95.5-98.5%, curing agent 1-3%, additive 0.5-1.5%; if epoxy resin is used, the curing agent content can be calculated according to the epoxy equivalent; if polyurethane is used, two polyurethane components with different polymerization degrees can be selected and mixed, and the two can be curing agents of each other, and the resin glue containing the curing agent is stored in a dipping tank;

[0034] The high-strength continuous fiber 4 in this embodiment is made of high elastic modulus glass fiber, such as basalt fiber or carbon fiber, and its fiber Young's modulus is usually 50-220GPa. The high-strength continuous fiber 4 is firstly soaked in resin glue through the dipping tank 5, and then pre-extruded by the extrusion device 6 to remove excess resin glue, so as to ensure that the weight percentage of the resin glue in the prepared FRP thin-walled pole is 15-50%, and the weight percentage of the high-strength continuous fiber 4 is 50%-85%, preferably 30% of the resin glue and 70% of the high-strength continuous fiber 4;

[0035] The high-strength continuous fiber 4 impregnated with resin glue is pulled and wound onto a core mold 8 pre-coated with a release agent by a yarn pulling arm or a yarn pulling vehicle. The core mold 8 is mounted on a rotating shaft and continuously rotates driven by the rotating shaft. The winding direction of the high-strength continuous fiber 4 forms an angle of 45° with the axis of the core mold 8. The yarn pulling arm or the yarn pulling vehicle reciprocates in a direction parallel to the rotating shaft to achieve bidirectional traction of the high-strength continuous fiber 4 in the winding direction and the forward direction. The yarn pulling vehicle 7 can reciprocate in a direction parallel to the rotating shaft through a guide rail;

[0036] The appropriate running speed of the yarn drawing arm or yarn drawing vehicle is controlled by computer programming to ensure uniform yarn distribution. At the same time, the yarn drawing arm or yarn drawing vehicle is set to have different running speeds during each reciprocating motion to achieve an uneven thickness structure of the FRP thin-walled pole with gradually increasing wall thickness from top to bottom. The wall thickness of the prepared FRP thin-walled pole is 2-15mm;

[0037] The wound core mold 8 is placed in a horizontal oven for curing at a curing temperature of 110° C. to 170° C. After curing, the core mold 8 is removed from the mold to obtain a FRP thin-walled pole.

[0038] The manufacturing method of the flange is: before the core mold 8 is cured after winding, the yarn pulling arm or the yarn pulling vehicle is controlled to stop at the bottom position of the FRP thin-walled pole, the core mold 8 continues to rotate, and the high-strength continuous fiber 4 impregnated with resin glue is wound at the bottom of the FRP thin-walled pole in multiple layers to a certain thickness to obtain a flange, or a flange made by another winding process is bonded to the bottom of the FRP thin-walled pole by resin glue, and finally the FRP thin-walled pole and the flange connected to the bottom are cured together.

[0039] Example 2

[0040] refer to Figure 1 In this embodiment, a FRP thin-walled pole is provided, which includes a pole body 1. The pole body 1 is in the shape of a truncated cone or a regular prism that is gradually thickened from top to bottom and is hollow inside. When the pole body 1 is in the shape of a regular prism, the cross-sectional shape of the pole body 1 may be a regular pentagon, a regular hexagon, a regular octagon or other regular polygons. In this embodiment, the pole body 1 is in the shape of a truncated cone, and the wall thickness of the pole body 1 gradually increases from top to bottom. The wall thickness of the pole body 1 in this embodiment is 2-15mm, with about 5mm being the best. The pole body 1 is made of multiple layers of FRP material, and a top end cap is provided on the pole body 1 to prevent debris from entering the hollow part. Figure 4 As shown, at least one layer of reinforcing ribs 3 is arranged inside the pole body 1. The reinforcing ribs 3 can be in a cross shape, a crisscross shape or a snowflake shape. In this embodiment, the reinforcing ribs 3 are in a cross shape.

[0041] The FRP thin-walled pole of this embodiment can be 12-15 meters high. For the convenience of installation, the pole body 1 can be directly buried in the soil. The 15-meter pole body needs to be buried at a depth of 2.5 meters, and the 12-meter pole body needs to be buried at a depth of 1.5 meters. A flange 2 can also be set at the bottom end of the pole body 1. Figure 2 A plurality of bolt mounting holes are arranged on the flange 2. The flange 2 is integrally formed by winding FRP material at the bottom of the pole body 1 or the pre-made flange 2 is bonded to the bottom of the pole body 1 by resin glue. A plurality of groups of ribs 21 can be arranged on the flange 2. The ribs 21 and the pole body 1 can be bonded by resin glue. The pole is fixed by fixing the flange to the concrete base.

[0042] A FRP thin-walled pole in this embodiment is prepared by a winding process. Figure 3 Any medium or large winding equipment can complete the winding process. Since the FRP thin-walled pole in this embodiment is provided with reinforcing ribs, the reinforcing ribs and the inner wall of the pole can be preformed by hand lay-up, that is, the reinforcing ribs are first fixed and used as a skeleton for winding, and several layers of high-strength continuous fiber cloth impregnated with resin glue are wound on the outer surface of the reinforcing ribs by hand lay-up to form the inner wall of the pole. The mold body including the reinforcing ribs and the inner wall of the pole obtained by hand lay-up preforming serves as a core mold for winding, and no demoulding treatment is required.

[0043] The manufacturing method of the FRP thin-walled pole comprises the following steps:

[0044] Prepare resin glue, which contains resin matrix, curing agent, initiator, accelerator, etc., and also includes anti-ultraviolet and anti-aging additives. The proportion of each component can be prepared according to the raw material instructions. For example, if the resin matrix is ​​polyester, the typical formula is (by weight): polyester matrix 95.5-98.5%, curing agent 1-3%, additive 0.5-1.5%; if epoxy resin is used, the curing agent content can be calculated according to the epoxy equivalent; if polyurethane is used, two polyurethane components with different polymerization degrees can be selected and mixed, and the two can be curing agents of each other, and the resin glue containing the curing agent is stored in a dipping tank;

[0045] The FRP material in this embodiment is a high elastic modulus glass fiber, such as basalt fiber or carbon fiber, which usually has a fiber Young's modulus of 50-220 GPa. The high-strength continuous fiber 4 is firstly impregnated with resin glue through a dipping tank 5, and then pre-extruded by an extrusion device 6 to remove excess resin glue, ensuring that the weight percentage of the resin glue in the prepared FRP thin-walled pole accounts for 15-50%, and the weight percentage of the high-strength continuous fiber 4 accounts for 50%-85%, preferably 30% of the resin glue and 70% of the high-strength continuous fiber 4;

[0046] The high-strength continuous fiber 4 impregnated with resin glue is pulled and wound onto the core mold 8 by a yarn pulling arm or a yarn pulling vehicle. The core mold 8 is installed on the rotating shaft and rotates continuously driven by the rotating shaft. The winding direction of the high-strength continuous fiber 4 forms an angle of 45° with the axis of the core mold. The yarn pulling arm or the yarn pulling vehicle reciprocates in a direction parallel to the rotating shaft to achieve bidirectional traction of the high-strength continuous fiber 4 in the winding direction and the forward direction. The yarn pulling vehicle 7 can reciprocate in a direction parallel to the rotating shaft through a guide rail;

[0047] The appropriate running speed of the yarn drawing arm or yarn drawing vehicle is controlled by computer programming to ensure uniform yarn distribution. At the same time, the yarn drawing arm or yarn drawing vehicle is set to have different running speeds during each reciprocating motion to achieve an uneven thickness structure of the FRP thin-walled pole with gradually increasing wall thickness from top to bottom. The wall thickness of the prepared FRP thin-walled pole is 2-15mm;

[0048] The wound core mold 8 is placed in a horizontal oven for curing at a temperature of 110° C. to 170° C. After curing, there is no need to demould, and the FRP thin-walled pole is obtained.

[0049] The manufacturing method of the flange is as follows: before the core mold is cured after winding is completed, the yarn drawing arm or the yarn drawing vehicle is controlled to stop at the bottom position of the FRP thin-walled pole, the core mold continues to rotate, and the high-strength continuous fiber 4 impregnated with resin glue is wound at the bottom of the FRP thin-walled pole in multiple layers to a certain thickness to obtain the flange, or the flange made by another winding process is bonded to the bottom of the FRP thin-walled pole by resin glue, and finally the FRP thin-walled pole and the flange connected to the bottom are cured together.

[0050] The FRP thin-walled pole of the present invention adopts FRP material to form an integrated hollow structure through a winding molding process. It has the characteristics of high strength, strong wind resistance, not easy to bend and shake, light weight, and can be manually carried, which improves the construction safety of the project and reduces the project cost. The construction is simple and has excellent properties such as strong corrosion resistance and long aging resistance. The service life of the pole is extended and the maintenance cost in the later operation is reduced. It is designed as a thin-walled structure with the advantages of uniform stress distribution, reasonable force, avoidance of internal stress, etc. It also has good insulation, reduces eddy current loss and the influence of tower eddy current on the power system, and meets various requirements for power transmission.

[0051] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A FRP thin-walled pole, characterized in that: The FRP thin-walled pole comprises a pole body (1), the pole body (1) is in the shape of a truncated cone or a regular prism that is gradually thickened from top to bottom and hollow inside, the wall thickness of the pole body (1) gradually increases from top to bottom, the pole body (1) is formed by winding multiple layers of FRP material, and the top end of the pole body (1) is provided with a head; a flange (2) is provided at the bottom end of the pole body (1), and a plurality of bolt mounting holes are provided on the flange (2); the flange (2) is formed by integrally winding the bottom of the pole body (1) with the FRP material, or the flange (2) is bonded to the bottom of the pole body (1) by resin glue; a plurality of groups of ribs (21) are provided on the flange (2), and the ribs (21) are bonded to the pole body (1) by resin glue; at least one layer of reinforcing ribs (3) is provided inside the pole body (1); The FRP thin-walled pole is manufactured by a winding process, and the manufacturing method comprises the following steps: Prepare a resin glue solution, wherein the resin glue solution contains a curing agent, and store the resin glue solution containing the curing agent in a dipping tank; The high-strength continuous fiber is firstly soaked in resin glue in a dipping tank, and then the excess resin glue is removed by pre-extrusion in an extrusion device, so as to ensure that the weight percentage of the resin glue in the prepared FRP thin-walled pole is 15-50%, and the weight percentage of the high-strength continuous fiber is 50%-85%; The high-strength continuous fiber impregnated with resin glue is pulled and wound onto a core mold pre-coated with a release agent by a yarn drawing arm or a yarn drawing vehicle. The core mold is installed on a rotating shaft and rotates continuously driven by the rotating shaft. The winding direction of the high-strength continuous fiber forms an angle of 45° with the axis of the core mold. The yarn drawing arm or the yarn drawing vehicle reciprocates in a direction parallel to the rotating shaft to achieve bidirectional traction of the high-strength continuous fiber in the winding direction and the forward direction. The appropriate running speed of the yarn drawing arm or yarn drawing vehicle is controlled by computer programming to ensure uniform yarn distribution. At the same time, the yarn drawing arm or yarn drawing vehicle is set to have different running speeds during each reciprocating motion to achieve an uneven thickness structure of the FRP thin-walled pole with gradually increasing wall thickness from top to bottom. The wall thickness of the prepared FRP thin-walled pole is 2-15mm; The wound core mold is placed in a horizontal oven for curing at a temperature of 110°C-170°C. After curing, the core mold is removed from the mold to obtain an FRP thin-walled pole. The manufacturing method also includes: before the core mold is cured after winding, controlling the yarn drawing arm or the yarn drawing vehicle to stop at the bottom position of the FRP thin-walled pole, the core mold continues to rotate, and the high-strength continuous fiber impregnated with resin glue is wound at the bottom of the FRP thin-walled pole in multiple layers to a certain thickness to obtain a flange, or the flange made by another winding process is bonded to the bottom of the FRP thin-walled pole by resin glue, and finally the FRP thin-walled pole and the flange connected to the bottom are cured together.

2. The FRP thin-walled pole according to claim 1, characterized in that: The reinforcing rib (3) is in a cross shape, a crisscross shape or a snowflake shape.

3. The FRP thin-walled pole according to claim 1, characterized in that: When the pole body (1) is in the shape of a regular prism as a whole, the cross-sectional shape of the pole body (1) is a regular pentagon, a regular hexagon or a regular octagon.

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