High-strength corrosion-resistant pipe
By combining multi-material external protective pipes and anti-corrosion filling layers in prestressed steel cylinder concrete pipes, the problems of insufficient crack resistance and anti-corrosion performance of cement mortar protective layers are solved, achieving all-round anti-corrosion protection, improving the durability and adaptability of the pipeline, and reducing maintenance costs.
Patent Information
- Application Number
- CN202610424224.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-04-01
- Publication Date
- 2026-06-16
AI Technical Summary
The existing cement mortar protective layer of prestressed steel cylinder concrete pipes has insufficient crack resistance and corrosion resistance, and cannot adapt to different corrosive environments, resulting in shortened pipeline durability and service life, increased maintenance costs and safety hazards.
The external protective pipe and anti-corrosion filling layer are made of a variety of materials, eliminating the traditional cement mortar protective layer. By filling the space between the prestressed steel wire layer and the external protective pipe with a variety of anti-corrosion filling materials, a multi-layer protective structure is formed, including external protective pipes made of materials such as plastic, stainless steel, and ductile iron, and anti-corrosion filling layers made of materials such as concrete, mortar, modified mortar, and epoxy mortar, so as to achieve all-round anti-corrosion protection.
It significantly improves the durability and adaptability of pipelines, extends their service life, reduces maintenance costs, adapts to different corrosive environments and pressure conditions, and enhances the overall rigidity and deformation resistance of pipelines.
Smart Images
Figure CN122216420A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of concrete pipe technology, and more particularly to a high-strength corrosion-resistant pipe. Background Technology
[0002] Prestressed concrete cylinder pipe (PCCP) is a composite pipe made of high-strength concrete core with steel cylinder, wrapped with prestressed steel wire, and then sprayed with cement mortar protective layer. It combines the tensile and sealing properties of steel with the compressive properties of concrete. It has the advantages of high strength, high rigidity, good impermeability and convenient installation, and is widely used in various water conservancy and municipal pipeline projects.
[0003] However, existing prestressed concrete cylinder pipes have significant durability defects. The cement mortar protective layer set outside the prestressed steel wire layer is a key structure to protect the internal prestressed steel wires and steel cylinder from corrosion, but it has inherent performance deficiencies: On the one hand, the cement mortar itself has limited crack resistance and impermeability, and is prone to micro-cracks under conditions such as temperature changes and soil settlement. Corrosive media in the external soil (such as Cl⁻, SO4²⁻) and corrosive components in the water can easily penetrate through the cracks, leading to electrochemical corrosion of the prestressed steel wires and steel cylinder, which in turn causes steel wire breakage, steel cylinder perforation, and ultimately pipe bursts and leaks, seriously affecting the safe operation of the pipeline system. On the other hand, the anti-corrosion performance of the cement mortar protective layer is limited and cannot adapt to highly corrosive environments such as saline-alkali land and coastal areas. Moreover, the type of outer protective structure and internal filling material is fixed and cannot be flexibly adapted to different working conditions, resulting in a significant reduction in pipeline service life, increasing engineering maintenance costs and safety hazards.
[0004] Current solutions to address these shortcomings primarily involve optimizing the cement mortar mix ratio or adding a coating to its surface. However, these solutions fail to overcome the inherent limitations of cement mortar as an external protective layer for the steel wire layer and its singular use as a filler material. The improvement in corrosion resistance is limited, failing to fundamentally solve the corrosion problem and cannot adapt to the personalized needs of different corrosion intensities and application scenarios. Therefore, there is an urgent need for a new type of prestressed steel cylinder concrete pipe structure that allows for flexible selection of the outer protective pipe material, diverse filler types, and can completely replace the traditional cement mortar protective layer while significantly improving the corrosion resistance of the pipeline through structural innovation. Summary of the Invention
[0005] The purpose of this application is to propose a high-strength corrosion-resistant pipe that achieves all-round corrosion protection and improves the durability, adaptability and practicality of pipelines.
[0006] This application is implemented as follows: A high-strength corrosion-resistant pipe includes, from the inside out, an inner concrete layer, a steel cylinder, an outer concrete wall, a prestressed steel wire layer, an anti-corrosion filling layer, and an outer protective pipe, all arranged coaxially. The outer protective pipe is made of any one of the following materials: plastic, anti-corrosion steel pipe, stainless steel, or ductile iron. The anti-corrosion filling layer is filled between the prestressed steel wire layer and the protective concrete layer, and is tightly bonded to both the prestressed steel wire layer and the protective concrete layer.
[0007] Furthermore, the prestressed steel wire layer is formed by one or more layers of steel wires uniformly wrapped around the outer concrete wall.
[0008] Furthermore, a socket steel ring and a spigot steel ring are fixedly connected to both ends of the steel cylinder, respectively; the two connected high-strength corrosion-resistant pipe sections are sealed by the matching insertion of the socket steel ring of the front section and the spigot steel ring of the rear section; an interface anti-corrosion filling ring is provided between the two connected high-strength corrosion-resistant pipe sections, the inner end of the interface anti-corrosion filling ring is sealed with the inner end face of the socket steel ring of the front section and the outer end face of the spigot steel ring of the rear section, the middle end of the interface anti-corrosion filling ring is sealed with the anti-corrosion filling layer of the two connected high-strength corrosion-resistant pipe sections, and the outer end of the interface anti-corrosion filling ring extends to the outside of the external protective pipe of the two high-strength corrosion-resistant pipe sections and extends forward and backward, thereby forming a cap that covers the two external protective pipe sections and forms a seal.
[0009] Furthermore, the filling material of the anti-corrosion filling layer includes any one or more combinations of concrete, mortar, modified mortar layer, and epoxy mortar; when the anti-corrosion performance requirements are high and structural strength needs to be considered, the filling material of the anti-corrosion filling layer is concrete or epoxy mortar; when the construction convenience requirements are high and the corrosion intensity of the working condition is moderate, the filling material of the anti-corrosion filling layer is mortar or modified mortar layer, and the modified mortar layer is polymer modified mortar or anti-corrosion modified mortar; for high adhesion, impermeability and anti-corrosion performance, the filling material of the anti-corrosion filling layer is epoxy mortar.
[0010] Furthermore, the steel cylinder is made of thin steel plate rolled and welded. The inner wall of the steel cylinder is tightly bonded to the inner concrete layer, the outer wall of the steel cylinder is tightly bonded to the outer concrete layer, and the outer concrete layer is tightly bonded to the prestressed steel wire layer. The prestressed steel wire layer is formed by uniformly winding one or more layers of high-strength prestressed steel wires along the axial direction of the outer concrete layer. After winding, the surface of the prestressed steel wire layer is flat and tightly bonded to the anti-corrosion filling layer.
[0011] Furthermore, the internal concrete layer is made of cast concrete with a strength grade of not less than C50 and a water-cement ratio of not more than 0.45. Steel fibers or polymer fibers are incorporated into the internal concrete layer.
[0012] Furthermore, both the socket steel ring and the spigot steel ring are made of carbon structural steel and are welded and fixed to the steel cylinder respectively. The outer side of the spigot steel ring is provided with a sealing groove for placing the sealing rubber ring, so as to realize a flexible sealing connection between adjacent pipes.
[0013] By implementing the above technical solution, this application achieves comprehensive corrosion protection by eliminating the cement mortar protective layer outside the steel wire layer, setting an external protective pipe with various materials available outside the steel wire layer, and filling the space between the steel wire layer and the external protective pipe with various anti-corrosion filler layers, thus forming a multi-layer protective structure and improving the durability, adaptability, and practicality of the pipeline. Attached Figure Description
[0014] The specific structure of this application is given by the following figures and embodiments: Figure 1 This is a structural diagram of this application.
[0015] Legend: 1. Inner concrete layer, 2. Steel cylinder, 3. Outer concrete wall, 4. Prestressed steel wire layer, 5. Anti-corrosion filling layer, 6. External protective pipe, 7. Socket steel ring, 8. Spiral steel ring, 9. Interface anti-corrosion filling ring, 10. Cap. Detailed Implementation
[0016] This application is not limited to the following embodiments, and the specific implementation method can be determined according to the technical solution of this application and the actual situation.
[0017] like Figure 1 As shown, a high-strength corrosion-resistant pipe includes an inner concrete layer 1, a steel cylinder 2, an outer wall concrete 3, a prestressed steel wire layer 4, an anti-corrosion filling layer 5, and an outer protective pipe 6 arranged coaxially from the inside to the outside. The outer protective pipe 6 can be made of any one of the following materials: plastic, anti-corrosion steel pipe, stainless steel, or ductile iron. The anti-corrosion filling layer 5 is filled between the prestressed steel wire layer 4 and the protective concrete layer, and the anti-corrosion filling layer 5 is tightly bonded to both the prestressed steel wire layer 4 and the protective concrete layer.
[0018] The thickness of the anti-corrosion filling layer 5 is not less than 600um. The inner diameter of the outer protective pipe 6 and the outer diameter of the prestressed steel wire layer 4 can be flexibly adjusted to ensure that the anti-corrosion filling layer 5 can completely wrap the prestressed steel wire and tightly fill the gap between the prestressed steel wire and the outer protective pipe 6, forming a solid overall structure.
[0019] The material of the external protective pipe 6 should be selected according to the operating conditions. When used in highly corrosive environments (such as coastal areas and saline-alkali land), plastic pipes or stainless steel pipes are preferred. For plastic pipes, PVC, CPVC, polypropylene (PP) or polyvinylidene fluoride (PVDF) are preferred. When used in conditions that withstand large external pressure, steel pipes or ductile iron pipes are preferred.
[0020] This application completely eliminates the traditional cement mortar protective layer, which is prone to cracking and has poor corrosion resistance. The external protective pipe 6 can be flexibly selected according to different corrosion intensities and external pressure conditions to adapt to various application scenarios. At the same time, an anti-corrosion filling layer 5 is set between the prestressed steel wire layer 4 and the external protective pipe. The filling material can be selected from various anti-corrosion types, including but not limited to concrete, mortar, modified mortar layer, epoxy mortar, etc., which can be precisely adapted according to anti-corrosion requirements, forming a double external protection structure of "external protective pipe 6 + anti-corrosion filling layer 5". This fundamentally avoids the electrochemical corrosion of the prestressed steel wire and steel cylinder 2, forming all-round and long-term anti-corrosion protection, and greatly improving the adaptability of the pipeline in different highly corrosive environments.
[0021] This application features a highly stable and practical structure: the external protective pipe 6 is made of materials selected according to the working conditions, balancing corrosion resistance and structural strength, and can withstand external corrosion as well as external pressure and impact; the protective concrete layer is connected to the anti-corrosion filling layer 5, which not only assists in corrosion protection but also firmly connects the prestressed steel wires of the prestressed steel wire layer 4 to the outer protective pipe as a whole, playing a supporting, fixing, and buffering role. Combined with the tight fit between the internal high-strength concrete layer 1 and the steel cylinder 2, the overall rigidity, strength, and deformation resistance of the pipeline are significantly improved, effectively resisting the effects of soil settlement, temperature difference changes, external impacts, and other working conditions, and reducing the risk of pipeline bursting and damage.
[0022] This application offers extended service life and low maintenance costs: Through a comprehensive design of "double external protection + internal corrosion protection" and flexible adaptation of multiple materials and filling types, it can effectively prevent corrosion damage to the internal steel cylinder 2 and prestressed steel wire layer 4. At the same time, the anti-corrosion filling layer 5 can protect the prestressed steel wire from friction damage, and the external protective pipe 6 can protect the anti-corrosion filling layer 5 from friction damage. Compared with traditional prestressed steel cylinder 2 concrete pipes, the service life is greatly improved, and the cost of pipeline maintenance and replacement is significantly reduced, making it suitable for the needs of century-long engineering construction.
[0023] The manufacturing process of this application is simple and flexible: the spraying and curing process of the cement mortar protective layer is eliminated. It is only necessary to fill the gap between the prestressed steel wire layer 4 and the external protective pipe 6 of a suitable material with the corresponding type of anti-corrosion filler layer 5. The process is simple and easy to operate, which simplifies the manufacturing process, shortens the production cycle, and reduces the manufacturing cost. At the same time, the selection of multiple materials and filler types can be adapted to pipe designs with different diameters, pressure levels, and corrosion conditions, which is convenient for large-scale production and promotion.
[0024] This application has a wide range of applications: the material of the external protection pipe 6 and the type of the anti-corrosion filling layer 5 can be flexibly selected according to different corrosive environments and different external pressure requirements. At the same time, the thickness and strength level of each layer structure can be adjusted, making it suitable for various scenarios such as long-distance water transmission, urban water supply, industrial drainage, sewage transportation, and saline-alkali land, coastal areas, and high-pressure conditions. The application scenarios are flexible and diverse, and the practicality is greatly improved.
[0025] like Figure 1 As shown, the prestressed steel wire layer 4 is formed by one or more layers of steel wires uniformly wrapped around the outer wall concrete 3.
[0026] like Figure 1 As shown, the two ends of the steel cylinder 2 are fixedly connected with a socket steel ring 7 and a spigot steel ring 8, respectively. The two connected high-strength corrosion-resistant pipe sections are sealed by the matching insertion of the socket steel ring 7 of the front section and the spigot steel ring 8 of the rear section. An interface anti-corrosion filling ring 9 is provided between the two connected high-strength corrosion-resistant pipe sections. The inner end of the interface anti-corrosion filling ring 9 is sealed with the inner end face of the socket steel ring 7 of the front section and the outer end face of the spigot steel ring 8 of the rear section, respectively. The middle end of the interface anti-corrosion filling ring 9 is sealed with the anti-corrosion filling layer 5 of the two connected high-strength corrosion-resistant pipe sections, respectively. The outer end of the interface anti-corrosion filling ring 9 extends to the outside of the external protective pipe 6 of the two high-strength corrosion-resistant pipe sections and extends forward and backward, thereby forming a cap 10 that covers the two external protective pipe sections 6 and forms a seal.
[0027] This prevents corrosive media from penetrating the anti-corrosion filler layer 5, the prestressed steel wire layer 4, and the steel cylinder 2 from the ends.
[0028] like Figure 1 As shown, the filling material of the anti-corrosion filling layer 5 includes any one or more combinations of concrete, mortar, modified mortar layer, and epoxy mortar; when the anti-corrosion performance requirements are high and structural strength needs to be considered, the filling material of the anti-corrosion filling layer 5 is concrete or epoxy mortar; when the construction convenience requirements are high and the corrosion intensity of the working condition is moderate, the filling material of the anti-corrosion filling layer 5 is mortar or modified mortar layer, and the modified mortar layer is polymer modified mortar or anti-corrosion modified mortar; for high adhesion, impermeability and anti-corrosion performance, the filling material of the anti-corrosion filling layer 5 is epoxy mortar.
[0029] The anti-corrosion filler layer 5 has good fluidity and adhesion, which can tightly wrap the prestressed steel wire of the prestressed steel wire layer 4 and adhere to the inner wall of the anti-corrosion filler layer 5, playing an auxiliary role in anti-corrosion and support and fixation, while avoiding damage caused by friction between the prestressed steel wire and the anti-corrosion filler layer 5.
[0030] like Figure 1As shown, the steel cylinder 2 is made of thin steel plate rolled and welded. The inner wall of the steel cylinder 2 is tightly bonded to the inner concrete layer 1, the outer wall of the steel cylinder 2 is tightly bonded to the outer concrete 3, and the outer concrete 3 is tightly bonded to the prestressed steel wire layer 4. The prestressed steel wire layer 4 is formed by one or more layers of high-strength prestressed steel wires uniformly wound along the axial direction of the outer concrete 3. After winding, the surface of the prestressed steel wire layer 4 is flat and tightly bonded to the anti-corrosion filling layer 5.
[0031] like Figure 1 As shown, the inner concrete layer 1 is made of concrete with a concrete strength grade of not less than C50 and a water-cement ratio of not more than 0.45. Steel fibers or polymer fibers are incorporated into the inner concrete layer 1.
[0032] It can improve the crack resistance and impermeability of concrete, ensure that the internal concrete layer 1 is free of cracks, and prevent the medium transported in the pipe from corroding the inner wall of the steel cylinder 2.
[0033] like Figure 1 As shown, both the socket steel ring 7 and the spigot steel ring 8 are made of carbon structural steel and are welded and fixed to the steel cylinder 2 respectively. The outer side of the spigot steel ring 8 is provided with a sealing groove for placing the sealing rubber ring, so as to realize a flexible sealing connection between adjacent pipes.
[0034] This allows for a flexible, sealed connection between adjacent pipes, preventing water leakage and the intrusion of corrosive media at pipe joints.
[0035] Example 1: The external protective pipe 6 is made of stainless steel with a wall thickness of 3mm. Its inner diameter is 20mm larger than the outer diameter of the prestressed steel wire layer 4 to ensure a tight fit. The anti-corrosion filling layer 5 is made of high-strength epoxy anti-corrosion mortar with a thickness of 20mm, which has excellent adhesion and anti-corrosion performance. The anti-corrosion filling layer 5 is tightly fitted to the external protective pipe 6. The steel cylinder 2 is made of thin steel plate with a thickness of 1.5mm rolled and welded. The outer wall is uniformly wound with high-strength prestressed steel wire to form the prestressed steel wire layer 4. The diameter of the prestressed steel wire is 5-8mm, and the winding density is adjusted according to the pipeline design pressure. The internal concrete layer 1 is made of C50 high-strength impermeable concrete with a water-cement ratio of 0.42. 1% steel fiber is added internally to improve crack resistance and impermeability. The socket steel ring 7 and the spigot steel ring 8 are made of Q235 carbon structural steel. The interface anti-corrosion filling ring 9 is filled with polyurethane sealant to fill the gap and seal the end sections of the protective concrete layer and the anti-corrosion filling layer 5.
[0036] Example 2: Adaptation to high-pressure, highly corrosive, saline-alkali land conditions The difference between this embodiment and Embodiment 1 is as follows: the external protective pipe 6 is made of ductile iron (accommodating both high pressure and strong corrosion), with a wall thickness of 8mm, suitable for working conditions with strong corrosion in saline-alkali soil and high external pressure; the anti-corrosion filling layer 5 is made of polymer-modified mortar (modified mortar layer), with a thickness of 20mm, which has both anti-corrosion and crack resistance; the internal concrete layer 1 is made of C50 high-strength impermeable concrete with a water-cement ratio of 0.38, and fiber is added to improve crack resistance and impermeability; the steel cylinder 2 is 2mm thick, and the prestressed steel wire diameter is 5-8mm; the sealing gasket is made of corrosion-resistant rubber material, suitable for the corrosion requirements of saline-alkali soil.
[0037] Example 3: Adaptation to Conventional Corrosion Municipal Water Supply Conditions The difference between this embodiment and Embodiment 1 is as follows: the external protective pipe 6 is made of PVC plastic pipe (conventional anti-corrosion, low cost), with a wall thickness of 8mm, suitable for the conventional corrosion conditions of municipal water supply; the anti-corrosion filling layer 5 is made of ordinary mortar (easy to construct, low cost), with a thickness of 20mm; the internal concrete layer 1 does not contain fibers and is poured with conventional C50 high-strength impermeable concrete; the steel cylinder 2 is 1.5mm thick, and the prestressed steel wire 5 has a diameter of 4mm; the anti-corrosion filling layer 5 and the protective layer pipe are ensured to fit tightly.
[0038] Example 4: Adaptation to high-strength corrosion-resistant industrial drainage conditions The difference between this embodiment and Embodiment 1 is as follows: the external protective pipe 6 is made of high-strength steel pipe with a wall thickness of 12mm, which is suitable for industrial drainage with large external impacts; the anti-corrosion filling layer 5 is filled with high-performance concrete composite with a total thickness of 20mm; the internal concrete layer 1 is made of C50 high-strength impermeable concrete with a water-cement ratio of 0.40 and steel fibers are added; the steel cylinder 2 has a thickness of 1.5mm and a prestressed steel wire diameter of 5mm; the outer wall of the external protective pipe 6 is coated with an anti-corrosion coating to further improve its anti-corrosion performance.
[0039] In this article, terms such as "up," "down," "front," "back," "left," and "right" are used only to indicate the relative positional relationship between related parts, rather than to define the absolute position of these related parts.
[0040] The above technical features constitute the embodiments of this application, which have strong adaptability and implementation effect. Non-essential technical features can be added or removed according to actual needs to meet the needs of different situations.
Claims
1. A high-strength corrosion-resistant pipe, characterized in that... It includes, from the inside out, an inner concrete layer, a steel cylinder, an outer concrete wall, a prestressed steel wire layer, an anti-corrosion filling layer, and an outer protective pipe, arranged coaxially. The outer protective pipe can be made of any one of the following materials: plastic, anti-corrosion steel pipe, stainless steel, or ductile iron. The anti-corrosion filling layer is filled between the prestressed steel wire layer and the protective concrete layer, and the anti-corrosion filling layer is tightly bonded to both the prestressed steel wire layer and the protective concrete layer.
2. The high-strength corrosion-resistant pipe according to claim 1, characterized in that: The prestressed steel wire layer is formed by one or more layers of steel wires being uniformly wound around the outer concrete wall.
3. A high-strength corrosion-resistant pipe according to claim 1 or 2, characterized in that: The two ends of the steel cylinder are fixedly connected with a socket steel ring and a spigot steel ring, respectively. The two connected high-strength corrosion-resistant pipe sections are sealed by the matching insertion of the socket steel ring of the front section and the spigot steel ring of the rear section. An interface anti-corrosion filling ring is provided between the two connected high-strength corrosion-resistant pipe sections. The inner end of the interface anti-corrosion filling ring is sealed with the inner end face of the socket steel ring of the front section and the outer end face of the spigot steel ring of the rear section, respectively. The middle end of the interface anti-corrosion filling ring is sealed with the anti-corrosion filling layer of the two connected high-strength corrosion-resistant pipe sections, respectively. The outer end of the interface anti-corrosion filling ring extends to the outside of the external protective pipe of the two high-strength corrosion-resistant pipe sections and extends forward and backward, thereby forming a cap that covers the two external protective pipe sections and forms a seal.
4. A high-strength corrosion-resistant pipe according to claim 1 or 2, characterized in that: The filling material for the anti-corrosion filling layer includes any one or more combinations of concrete, mortar, modified mortar layer, and epoxy mortar. When high anti-corrosion performance is required while structural strength needs to be considered, the filling material for the anti-corrosion filling layer is concrete or epoxy mortar. When high ease of construction is required and the corrosion intensity under working conditions is moderate, the filling material for the anti-corrosion filling layer is mortar or modified mortar layer, and the modified mortar layer is polymer modified mortar or anti-corrosion modified mortar. For high adhesion, impermeability and anti-corrosion performance, the filling material for the anti-corrosion filling layer is epoxy mortar.
5. A high-strength corrosion-resistant pipe according to claim 1 or 2, characterized in that: The steel cylinder is made of thin steel plate rolled and welded. The inner wall of the steel cylinder is tightly bonded to the inner concrete layer, the outer wall of the steel cylinder is tightly bonded to the outer concrete layer, and the outer concrete layer is tightly bonded to the prestressed steel wire layer. The prestressed steel wire layer is formed by one or more layers of high-strength prestressed steel wires uniformly wound along the axial direction of the outer concrete layer. After winding, the surface of the prestressed steel wire layer is flat and tightly bonded to the anti-corrosion filling layer.
6. A high-strength corrosion-resistant pipe according to claim 1 or 2, characterized in that: The internal concrete layer is made of cast concrete with a strength grade of not less than C50 and a water-cement ratio of not more than 0.
45. Steel fibers or polymer fibers are incorporated into the internal concrete layer.
7. A high-strength corrosion-resistant pipe according to claim 1 or 2, characterized in that: Both the socket steel ring and the spigot steel ring are made of carbon structural steel and are welded and fixed to the steel cylinder respectively. The outer side of the spigot steel ring is provided with a sealing groove for placing the sealing rubber ring, so as to realize a flexible sealing connection between adjacent pipes.