Prestressed concrete cylinder pipe and connecting structure thereof

Abstract

The invention relates to the technical field of pipelines, in particular to a prestressed concrete cylinder pipe and a connecting structure thereof.The prestressed concrete cylinder pipe comprises a pipe body, and a prestressed steel wire in the pipe body is configured to be coated with plastic in the straightened and prestressed state; the pipe body comprises a plastic protection layer, the material of the plastic protection layer is the same as that of the plastic wrapping the prestressed steel wire, and the plastic protection layer wraps the prestressed steel wire. The steel wire is subjected to plastic coating setting in a state of obtaining prestress after being straightened, namely, the steel wire is subjected to plastic coating anti-corrosion setting after being fully deformed, so that the steel wire is not easy to corrode; the prestressed steel wire serves as a pipe body prestress source and also serves as a rib for forming the plastic protection layer, the plastic protection layer and concrete or the steel cylinder are tightly connected into a whole, good pipe body protection is provided, steel wire corrosion prestress failure and even steel wire breakage are prevented, the occurrence probability of pipe explosion accidents is reduced, and the service life is prolonged. The prestressed steel cylinder concrete pipe is simple in structure, convenient to use and good in effect.

Description

Technical Field

[0001] The invention relates to the technical field of pipelines, in particular to a prestressed steel cylinder concrete pipe and a connection structure thereof. Background Art

[0002] Prestressed Concrete Cylinder Pipe (PCCP) is a water pipe made by winding annular prestressed steel wire on a high-strength concrete pipe core with a steel cylinder, and then spraying a dense cement mortar protective layer on it. It is a composite pipe composed of thin steel plate, high-strength steel wire and concrete. It fully and comprehensively exerts the tensile strength and easy sealing of steel and the compressive and corrosion resistance of concrete, and has the characteristics of high sealing, high strength and high impermeability.

[0003] PCCP is a widely used pipe, known for its large diameter, high pressure resistance and low cost. The existing buried PCCP includes an inner concrete layer, a thin steel cylinder, an outer concrete layer, a wound prestressed steel wire, and a mortar protective layer, which are arranged in sequence from the inside to the outside. The existing lined PCCP includes a concrete layer, a thin steel cylinder, a wound prestressed steel wire, and a mortar protective layer, which are arranged in sequence from the inside to the outside. The mortar protective layer is used to protect the prestressed steel wire from corrosion, but the anti-corrosion protection effect of the mortar protective layer is general.

[0004] In some existing steel wire anti-corrosion technologies, if the steel wire is pre-treated with anti-corrosion treatment before prestressed drawing, there is a high probability that the anti-corrosion layer will be damaged: because when the steel wire is treated with anti-corrosion (coating or plating), the steel wire is straightened and then coiled after treatment; when prestressed drawing is performed, it is straightened again and its diameter is reduced (to obtain prestress). During this deformation, and the friction of the prestressed equipment on the anti-corrosion layer, the anti-corrosion layer will be affected, the adhesion will be reduced, and it may even be damaged (fall off), thereby affecting its anti-corrosion effect.

[0005] According to the above, in the prior art, pipe burst accidents due to corrosion of prestressed steel wires occur frequently, and PCCP pipe products need to be further iterated and upgraded in order to avoid being eliminated by the industry. Summary of the invention

[0006] The purpose of the present invention is to provide a prestressed steel cylinder concrete pipe and its connection structure to address the problem that the prestressed steel wire in the existing PCCP in the prior art is first subjected to anti-corrosion treatment and then prestressed tensioning. The diameter of the steel wire is reduced in the process of obtaining prestress, and the anti-corrosion layer is affected by the friction of the prestressing equipment, etc., which reduces the adhesion and may even be damaged (fall off), making the prestressed steel wire easily corroded, resulting in frequent pipe burst accidents.

[0007] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] In a first aspect, the present invention provides a prestressed concrete cylinder pipe, including a pipe body, wherein the prestressed steel wires in the pipe body are configured to be coated with plastic in a straightened and prestressed state;

[0009] The pipe body includes a plastic protective layer, the material of the plastic protective layer is the same as the material of the plastic coating the prestressed steel wires, and the plastic protective layer wraps the prestressed steel wires.

[0010] By using the prestressed concrete cylinder pipe of the present invention, the steel wires are coated with plastic in a straightened and prestressed state, that is, the steel wires are coated with plastic for anti-corrosion after being fully deformed. The prestressed steel wires can be set as anti-corrosion steel wires, and the steel wire surface has a plastic coating layer. The plastic coating layer set after the steel wire deformation has the due strength and is not easy to crack, which simplifies the process and makes the steel wires not easy to be corroded; by setting the plastic protective layer with the same material as the plastic coating layer to wrap the prestressed steel wires, an outer protective layer is further formed. At the same time, the plastic protective layer and the plastic coating layer are easy to be integrally connected by hot melting. The forming process of the pipe body is easy to achieve. The prestressed steel wires serve as both the prestress source of the pipe body and the framework for the formation of the plastic protective layer, tightly connecting the plastic protective layer with the concrete or the steel cylinder into one body, providing good protection for the pipe body, preventing the steel wires from being corroded, the prestress from failing, and even the steel wires from breaking, reducing the probability of pipe burst accidents, and improving the service life. The prestressed concrete cylinder pipe has a simple structure, is convenient to use, and has good effects.

[0011] As a preferred technical solution of the present invention, the plastic protective layer is a PVC (polyvinyl chloride) layer, a PE (polyethylene) layer, a PP (polypropylene) layer, a PS (polystyrene) layer, a PET (polyethylene terephthalate) layer, a PU (polyurethane) layer, a PC (polycarbonate) layer, a PA (nylon) layer or an ABS (acrylonitrile-butadiene-styrene copolymer) layer.

[0012] As a preferred technical solution of the present invention, the pipe body includes a concrete layer, a steel cylinder and the plastic protective layer arranged in sequence from inside to outside, and the prestressed steel wires are wound around the outer wall of the steel cylinder and embedded in the plastic protective layer, that is, the pipe body is a lined PCCP pipe body.

[0013] As a preferred technical solution of the present invention, the pipe body includes an inner concrete layer, a steel cylinder, an outer concrete layer and the plastic protective layer arranged in sequence from inside to outside, and the prestressed steel wires are wound around the outer wall of the outer concrete layer and embedded in the plastic protective layer, that is, the pipe body is a buried PCCP pipe body.

[0014] In a second aspect, the present invention also provides a connection structure for a prestressed concrete cylinder pipe, including a joint, and the joint is sleeved on the end of the prestressed concrete cylinder pipe as described in any one of the above.

[0015] As a preferred technical solution of the present invention, an opening groove is provided on the joint, a sealing ring is provided in the opening groove, the inner ring wall of the sealing ring abuts against the outer wall of the pipe body, the outer ring wall and one side wall of the sealing ring abut against the joint, a pressing ring abuts against the other side wall of the sealing ring, and the pressing ring and the joint can move relatively along the axial direction of the pipe body.

[0016] With this structural arrangement, by adjusting the relative position between the pressing ring and the joint, the pressing ring can apply pressure to the sealing ring, forcing the sealing ring to deform and further tightly adhere to the outer wall of the pipe body to form a sealed connection.

[0017] As a further preferred technical solution of the present invention, a retaining ring is detachably connected to the side of the joint where the pressing ring is provided, a first bolt is threadedly connected to the retaining ring, and the end of the first bolt penetrates through the retaining ring and abuts against the pressing ring.

[0018] As a further preferred technical solution of the present invention, the retaining ring and the joint are connected by a second bolt.

[0019] As a preferred technical solution of the present invention, the joint is a flat joint, the flat joint connects two pipes with equal diameters, and the cross section of the flat joint is in a T shape.

[0020] As a preferred technical solution of the present invention, the joint is a reducing joint, the reducing joint connects two pipes with unequal diameters, and the cross section of the reducing joint is in a Z shape.

[0021] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0022] 1. A prestressed concrete cylinder pipe according to the present invention, wherein the steel wire is plastically coated under the prestressed state after being straightened, that is, the steel wire is plastically coated and anti-corrosion treated after sufficient deformation, so that the prestressed steel wire can be set as anti-corrosion steel wire. The surface of the steel wire has a plastic coating layer, and the plastic coating layer set after the deformation of the steel wire has the due strength and is not easy to crack, which simplifies the process and makes the steel wire not easy to be corroded; by arranging the plastic protection layer made of the same material as the plastic coating layer to wrap the prestressed steel wire, an outer protection layer is further formed. At the same time, the plastic protection layer and the plastic coating layer are easily melt-connected into one body, which is easy to achieve in the forming process of the pipe body. The prestressed steel wire serves both as the source of prestress of the pipe body and as the framework for the formation of the plastic protection layer, tightly connecting the plastic protection layer with the concrete or the steel cylinder into one body, providing good protection for the pipe body, preventing the corrosion of the steel wire, the failure of prestress and even the fracture of the steel wire, reducing the probability of pipe burst accidents and increasing the service life. The prestressed concrete cylinder pipe has a simple structure, is convenient to use and has good effects;

[0023] 2. A preferred connection structure of a prestressed concrete cylinder pipe according to the present invention, by adjusting the relative position between the pressing ring and the joint, the pressing ring can apply pressure to the sealing ring, forcing the sealing ring to deform and further tightly adhere to the outer wall of the pipe body to form a sealed connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a half-sectional view of a prestressed concrete cylinder pipe;

[0025] Figure 2 is Figure 1 an enlarged view of part A in

[0026] Figure 3 is a half-sectional view of the connection of equal-diameter pipes;

[0027] Figure 4 is Figure 3 an enlarged view of part B in

[0028] Figure 5 is a half-sectional view of the connection of stepped pipes;

[0029] Figure 6 is Figure 5 an enlarged view of part C in

[0030] Markings in the figure: 1 - pipe body, 11 - concrete layer, 12 - steel cylinder, 13 - prestressed steel wire, 14 - plastic protection layer, 2 - flat joint, 3 - sealing ring, 4 - retaining ring, 5 - second bolt, 6 - first bolt, 7 - pressing ring, 8 - foamed gasket, 9 - stepped joint. DETAILED DESCRIPTION OF THE INVENTION The present invention will be further described in detail below in combination with test examples and specific embodiments. However, it should not be understood that the scope of the above-mentioned subject matter of the present invention is limited to the following embodiments. All technologies implemented based on the content of the present invention belong to the scope of the present invention.

[0031] In the description of the specific embodiments of the present invention, unless otherwise specified, the expression terms indicating the orientation or positional relationship such as "upper", "lower", "left", "right", "center", "inner", "outer", etc. are all based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship when the invention product / device / device is commonly used. These orientation or positional relationship terms are only for the convenience of describing the present invention solution or simplifying the description in the specific embodiment, so as to facilitate technicians to quickly understand the solution, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, it cannot be understood as a limitation to the present invention.

[0032] In addition, if terms such as "horizontal", "vertical", "hanging", "parallel", etc. appear, it does not mean that the corresponding device / component / element is required to be absolutely horizontal or vertical or hanging or parallel, but can be slightly inclined or have a deviation. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. Or, it can be simply understood that the corresponding device / component / element is arranged in the directions of "horizontal", "vertical", "hanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still play its role in the solution of the present invention.

[0033] In addition, the expressions "first", "second", "third", etc. appearing in the terms are only used to distinguish the description of the same or similar components, and should not be understood as emphasizing or implying the relative importance of specific components.

[0034] In addition, in the description of the embodiments of the present invention, "several", "multiple", "a number of" represent at least 2. It can be any situation such as 2, 3, 4, 5, 6, 7, 8, 9, etc., and even can be more than 9.

[0035] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, when the terms "set", "installed", "connected", "coupled", "provided with", "laid", "arranged" appear, they 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 connection means commonly used in the art such as welding, riveting, bolting, or threaded connection. Such a connection can be a mechanical connection, an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two components.

[0036] In the related art, the anti-corrosion protection effect of the mortar protective layer is average. At the same time, in some existing steel wire anti-corrosion technologies, if the steel wire is pre-treated for anti-corrosion and then subjected to prestressed drawing, there is a high probability that the anti-corrosion layer will be damaged. Because when the steel wire is anti-corrosion treated (coated or plated), it is carried out while the steel wire is straightened, and then it is coiled after the treatment; when prestressed drawing is carried out, it is straightened again and its diameter is reduced (to obtain prestress). In this deformation, as well as the friction of the anti-corrosion layer by the prestressing equipment, the anti-corrosion layer will be affected, reducing the adhesion force, and even may be damaged (peeled off), thus affecting its anti-corrosion effect, making the prestressed steel wire easily corroded, and causing frequent accidents of pipe explosion. For this reason, the technical solution of this application is thus generated. The following will be described in conjunction with Figures 1 to 6 be elaborated.

[0037] Example 1

[0038] As Figure 1 and Figure 2 shown, a prestressed concrete cylinder pipe according to the present invention includes a pipe body 1. The pipe body 1 includes a concrete layer 11, a steel cylinder 12, and a plastic protective layer 14 arranged in sequence from the inside to the outside, that is, the pipe body 1 is a lined PCCP pipe body; a prestressed steel wire 13 is wound around the outer wall of the steel cylinder 12, and the prestressed steel wire 13 is embedded in the plastic protective layer 14; the prestressed steel wire 13 is configured to be coated with plastic in a straightened and prestressed state; the material of the plastic coating the prestressed steel wire 13 is the same as that of the plastic protective layer 14.

[0039] In an alternative embodiment, the plastic protective layer 14 is a PVC (polyvinyl chloride) layer, a PE (polyethylene) layer, a PP (polypropylene) layer, a PS (polystyrene) layer, a PET (polyethylene terephthalate) layer, a PU (polyurethane) layer, a PC (polycarbonate) layer, a PA (nylon) layer, or an ABS (acrylonitrile-butadiene-styrene copolymer) layer.

[0040] In an alternative embodiment, after the prestressed steel wire 13 is wound around the outer wall of the steel cylinder 12, the tube blank of the pipe body 1 is placed into a forming mold, and a plastic melt is injected. The plastic melt penetrates into the gaps between the prestressed steel wires 13 and adheres to the outer wall of the steel cylinder 12. The plastic melt is pressed and compacted to form the plastic protective layer 14. When the plastic melt penetrates into the gaps between the prestressed steel wires 13, the plastic melt and the plastic coating layer on the outer wall of the prestressed steel wire 13 are thermally fused into one body. Therefore, the prestressed steel wire 13 and the plastic protective layer 14 are combined into one body. The prestressed steel wire 13 serves as the skeleton of the plastic protective layer 14, as Figure 2 shown.

[0041] For the prestressed concrete cylinder pipe described in this embodiment, the steel wire is plastically coated in a prestressed state after being straightened, that is, after the steel wire is fully deformed, plastic coating and anti-corrosion are carried out. The prestressed steel wire can be set as an anti-corrosion steel wire. The surface of the steel wire has a plastic coating layer. The plastic coating layer set after the steel wire is deformed has due strength and is not easy to crack, which simplifies the process and makes the steel wire not easy to be corroded. By providing the plastic protective layer 14 made of the same material as the plastic coating layer to wrap the prestressed steel wire 13, an outer protective layer is further formed. At the same time, the plastic protective layer 14 and the plastic coating layer are easily thermally fused into one body, which is easy to achieve in the forming process of the pipe body 1. The prestressed steel wire 13 serves both as the prestress source of the pipe body 1 and as the skeleton for the formation of the plastic protective layer 14, tightly connecting the plastic protective layer 14 with the concrete or the steel cylinder into one body, providing good protection for the pipe body, preventing corrosion of the steel wire, prestress failure and even fracture of the steel wire, reducing the probability of pipe burst accidents, and increasing the service life. The prestressed concrete cylinder pipe has a simple structure, is convenient to use, and has good effects.

[0042] Embodiment 2

[0043] Not shown, for the prestressed concrete cylinder pipe described in the present invention, the difference from Embodiment 1 is that in this embodiment, the pipe body 1 is a buried PCCP pipe body. The pipe body 1 includes an inner concrete layer, a steel cylinder 12, an outer concrete layer, and the plastic protective layer 14 arranged in sequence from inside to outside. The prestressed steel wire 13 is wound around the outer wall of the outer concrete layer and embedded in the plastic protective layer 14.

[0044] Embodiment 3

[0045] As Figure 3 and Figure 4 shown, the connection structure of the prestressed concrete cylinder pipe described in the present invention includes a joint. The joint is sleeved on the end of the prestressed concrete cylinder pipe described in Embodiment 1 or Embodiment 2.

[0046] In an alternative embodiment, an opening groove is provided on the joint, and a sealing ring 3 is arranged in the opening groove. The inner ring wall of the sealing ring 3 abuts against the outer wall of the pipe body 1, the outer ring wall and one side wall of the sealing ring 3 abut against the joint, and a pressing ring 7 abuts against the other side wall of the sealing ring 3. The pressing ring 7 and the joint can move relative to each other along the axial direction of the pipe body 1.

[0047] As Figure 4 shown, a retaining ring 4 is detachably connected to the side of the joint where the pressing ring 7 is arranged, specifically by a second bolt 5. A first bolt 6 is threadedly connected to the retaining ring 4, and the end of the first bolt 6 penetrates through the retaining ring 4 and abuts against the pressing ring 7.

[0048] In an alternative embodiment, as Figure 4 shown, the joint is a flat joint 2. The flat joint 2 connects two pipe bodies 1 with the same diameter. The cross-section of the flat joint 2 is in a T shape, that is, an opening groove is provided on each of the two sides of the flat joint 2, and the position of the opening groove is close to one side of the pipe body 1. Among them, one opening groove corresponds to one pipe body 1, that is, two sealing rings 3 are respectively pressed against one pipe body 1 to achieve sealed connection, forming sealed butt joint of two pipe bodies 1 with the same diameter.

[0049] In an alternative embodiment, as Figure 4 shown, a foaming gasket 8 is abutted and arranged between two pipe bodies 1 with the same diameter.

[0050] For the connection structure of the prestressed concrete cylinder pipe described in this embodiment, by adjusting the relative position between the pressing ring 7 and the joint, the pressing ring 7 can apply pressure to the sealing ring 3, forcing the sealing ring 3 to deform and further tightly adhere to the outer wall of the pipe body 1 to form a sealed connection.

[0051] Embodiment 4

[0052] As Figure 5 and Figure 6 shown, the connection structure of the prestressed concrete cylinder pipe described in the present invention is different from that in Embodiment 3 in that, in this embodiment, the joint is a reducing joint 9.

[0053] The reducing joint 9 connects two pipe bodies 1 with different diameters, and the cross-section of the reducing joint 9 is in a Z shape.

[0054] As Figure 5As shown, the cross-section of the Z-shaped reducing joint 9 includes an upper horizontal part, a lower horizontal part, and an intermediate connecting part. The inner diameter of the upper horizontal part is adapted to the outer diameter of one of the pipe bodies 1, and the inner diameter of the lower horizontal part is adapted to the outer diameter of the other pipe body 1. The intermediate connecting part can be inclined relative to the upper horizontal part or can be perpendicular to the upper horizontal part. The intermediate connecting part can be linear or can be curved.

[0055] Embodiment 5

[0056] Not shown, for a prestressed concrete cylinder pipe according to the present invention, on the basis of Embodiment 1 or Embodiment 2, one end of the pipe body 1 is flared to form a socket. The inner diameter of the socket is adapted to the outer diameter of the pipe body 1, and the sealing design of the socket adopts the sealing design of the connection structure of the prestressed concrete cylinder pipe as described in Embodiment 3 or Embodiment 4 (reference can be made to Figure 6 ).

[0057] In this way, the prestressed concrete cylinder pipe products with a single pipe diameter can be directly connected in series and sealed for installation.

[0058] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A prestressed concrete cylinder pipe, comprising a pipe body (1), characterized in that, The prestressed steel wires (13) in the pipe body (1) are configured to be coated with plastic in a straightened and prestressed state; The pipe body (1) includes a plastic protective layer (14), the material of the plastic protective layer (14) is the same as the material of the plastic coating the prestressed steel wires (13), and the plastic protective layer (14) wraps the prestressed steel wires (13).

2. The prestressed concrete cylinder pipe according to claim 1, wherein The plastic protective layer (14) is a PVC layer, a PE layer, a PP layer, a PS layer, a PET layer, a PU layer, a PC layer, a PA layer or an ABS layer.

3. The prestressed concrete cylinder pipe according to claim 1, wherein The pipe body (1) includes a concrete layer (11), a steel cylinder (12) and the plastic protective layer (14) arranged in sequence from inside to outside. The prestressed steel wires (13) are wound around the outer wall of the steel cylinder (12) and embedded in the plastic protective layer (14).

4. The prestressed concrete cylinder pipe according to claim 1, wherein, The pipe body (1) includes an inner concrete layer, a steel cylinder (12), an outer concrete layer and the plastic protective layer (14) arranged in sequence from inside to outside. The prestressed steel wires (13) are wound around the outer wall of the outer concrete layer and embedded in the plastic protective layer (14).

5. A connection structure for a prestressed concrete cylinder pipe, characterized in that, It includes a joint, and the joint is sleeved on the end of the prestressed steel cylinder concrete pipe according to any one of claims 1-4.

6. The prestressed concrete cylinder pipe according to claim 5, characterized in that, An opening groove is provided on the joint, a sealing ring (3) is provided in the opening groove, the inner ring wall of the sealing ring (3) abuts against the outer wall of the pipe body (1), the outer ring wall and one side wall of the sealing ring (3) abut against the joint, the other side wall of the sealing ring (3) abuts against a pressure ring (7), and the pressure ring (7) and the joint can move relative to each other along the axial direction of the pipe body (1).

7. The prestressed concrete cylinder pipe according to claim 6, characterized in that, A retaining ring (4) is detachably connected to one side of the joint where the pressure ring (7) is provided. A first bolt (6) is threadedly connected to the retaining ring (4), and the end of the first bolt (6) penetrates through the retaining ring (4) and abuts against the pressure ring (7).

8. The prestressed concrete cylinder pipe according to claim 7, characterized in that, The retaining ring (4) and the joint are connected by a second bolt (5).

9. The prestressed concrete cylinder pipe according to any one of claims 5-8, characterized in that, The joint is a flat joint (2), the flat joint (2) connects two pipe bodies (1) with the same diameter, and the cross section of the flat joint (2) is in a T shape.

10. The prestressed concrete cylinder pipe according to any one of claims 5-8, characterized in that, The joint is a reducing joint (9), the reducing joint (9) connects two pipe bodies (1) with different diameters, and the cross section of the reducing joint (9) is in a Z shape.

Images