Universal connecting member for metal pipe and pccp pipe

Abstract

This invention belongs to the field of water supply and drainage and water conservancy pipeline connection technology, and discloses a universal connection component for metal pipes and PCCP pipes. The connection component is an overall metal tubular structure, including a PCCP butt end, a central reinforcing base, and a metal pipe butt end connected sequentially along the axial direction; the central reinforcing base is a thickened tubular load-bearing structure with a wall thickness greater than that of the two butt ends; the PCCP butt end can be a single rubber ring socket, a double rubber ring socket, or a PCCP adapter socket, and the metal pipe butt end can be a metal pipe socket, a metal pipe socket, or a metal flange, with one of each end combined with the central base to form a standard fixed pipe fitting; the connection component is integrally cast and annealed or segmented full welding stress-relief forming. This invention abandons the concrete reinforcement structure, has uniform and stable structural mechanical properties, comprehensive port adaptation coverage, can achieve standardized mass production, and is suitable for the connection of heterogeneous pipes in various water conveyance projects.

Description

Technical Field

[0001] This invention belongs to the field of water supply and drainage, water conservancy pipeline connection technology, specifically relating to a universal connection component for metal pipes and PCCP pipes. Background Technology

[0002] PCCP pipes (prestressed concrete cylinder pipes) are characterized by high pressure resistance, large diameter, corrosion resistance, and long service life, and are widely used in long-distance water transfer and urban main water transmission projects. Ductile iron pipes have excellent flexible joint performance, convenient construction, and strong seismic resistance, and are often used in urban pipe networks, branch pipes, valves, tees, and other pipe network nodes. Steel pipes have high strength and flexible processing, and are often used for large-diameter pipeline transitions under special working conditions. Various pipe materials play a role in different water transmission scenarios due to their own performance advantages, jointly forming a hierarchical and complete water transmission network system. The connection and connection between pipes of different materials has also become a common requirement in engineering construction.

[0003] Regarding the connection problem between steel pipes and PCCP pipes, Chinese Patent No. CN222334761U discloses a connector for steel pipes and PCCP pipes. This connector adopts a split structure design, consisting of two independent components: a socket connector and a spigot connector. Both types of connectors are equipped with a flange structure. One side of the flange is equipped with a connecting pipe adapted to the port of the PCCP pipe, and the other side is equipped with a connecting pipe for butt-connecting the steel pipe. The connection between the socket connector and the PCCP pipe is achieved by fitting the spigot steel ring of the PCCP pipe onto the socket connector and inserting the spigot connector into the socket steel ring of the PCCP pipe. The steel pipe side is connected by welding. At the same time, a concrete structure, steel mesh, ribs, and other reinforcing structures are set at the connection point to achieve a rigid connection between the two types of pipes.

[0004] However, this steel-concrete composite structure, which relies on the welding of thin-walled steel pipes and is reinforced with external ribs and concrete, has revealed many limitations in practical engineering applications. First, there are numerous weld seams between the pipe body, flanges, and ribs of this type of pipe, which have not undergone overall stress-relieving annealing. Residual stress is easily generated during welding, resulting in poor mechanical uniformity of the overall structure. Under large-diameter, high-pressure conditions, stress concentration and fatigue cracking are prone to occur at the weld seams. The reliability of the connection is significantly affected by the welding process level, making it difficult to uniformly control quality stability. Furthermore, the dimensional accuracy of the welded interfaces is difficult to control, and the consistency between different batches of products is poor. Second, the physical properties of the concrete reinforcement structure and the metal components differ significantly. Their coefficients of linear expansion and resistance to deformation are different. Under conditions such as temperature fluctuations, soil settlement, and pipeline displacement, the concrete-metal interface is prone to peeling and cracking. Over long-term operation, the structural strength and sealing performance deteriorate rapidly. Simultaneously, the concrete structure significantly increases the overall weight of the components, raising transportation and hoisting costs and increasing on-site construction difficulty. In some cases, on-site concrete pouring is required, making the construction process cumbersome. Furthermore, the manufacturing model of separate welding combined with concrete reinforcement is difficult to achieve standardized mass production. When there are differences in pipe specifications and port forms in different projects, each project needs to cut and weld materials separately and customize corresponding concrete structures. This results in a long production cycle, poor product interchangeability, and the inability to form a series of universal and standardized products. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a universal connecting component for metal pipes and PCCP pipes.

[0006] The technical solution of the universal connection component for metal pipes and PCCP pipes provided by this invention is as follows: A universal connecting component for metal pipes and PCCP pipes, the whole is a metal tubular structure, including a PCCP butt end, a central reinforcing base and a metal pipe butt end connected in sequence along the axial direction; The central reinforcing base is connected between the PCCP docking end and the metal pipe docking end. It is a thickened tubular load-bearing structure. The wall thickness of the central reinforcing base is greater than the wall thickness of the PCCP docking end and the metal pipe docking end. PCCP connectors are used to connect with external PCCP pipes. The structure of a PCCP connector can be any one of a single rubber ring socket, a double rubber ring socket, or a PCCP adapter socket. Metal pipe connectors are used to connect with external metal pipes. The structure of a metal pipe connector can be any one of a metal pipe socket, a metal pipe spigot, or a metal flange. The PCCP docking end and the metal pipe docking end are each pre-selected from three corresponding structures and combined with the central reinforcing base to form a standard pipe fitting adapted to specific heterogeneous pipe connection scenarios. The PCCP docking end, the central reinforcing base and the metal pipe docking end are integrally cast and subjected to integral stress-relief annealing after forming, or are combined by segmented full welding and subjected to integral stress-relief annealing after welding.

[0007] The beneficial effects of this invention are as follows: This invention adopts an all-metal tubular structure, abandoning the traditional concrete reinforcement design for connecting components, thus avoiding interface peeling and cracking problems caused by differences in the physical properties of heterogeneous materials. The central reinforced base uses a thickened tubular load-bearing structure, which can evenly distribute the internal water pressure of the pipe and the external soil settlement load, avoiding stress concentration at the interface and improving the overall pressure-bearing capacity and deformation resistance of the connecting components. Three optional structural forms are provided for both the PCCP and metal pipe connection ends, which can be pre-combined into various standard pipe fittings according to engineering needs, comprehensively covering different heterogeneous pipe connection scenarios. This replaces the traditional method of individual non-standard customization, improving product interchangeability and standardization, and reducing engineering procurement and maintenance costs. Both integral casting and segmented full welding forming methods are equipped with integral stress-relief annealing treatment, which can fully eliminate the internal stress generated during the forming process, ensuring uniform and stable structural mechanical properties and improving the long-term reliability of the connecting components.

[0008] Furthermore, the outer wall of the single rubber ring socket is provided with a single sealing ring groove for assembling a sealing rubber ring, which is adapted to the socket connection of the single rubber ring PCCP pipe.

[0009] Beneficial effects: It can form a stable radial seal with the socket of a single rubber ring PCCP pipe, is suitable for conventional low-pressure water transmission scenarios, has a simple structure, and is convenient for on-site assembly and operation.

[0010] Furthermore, the outer wall of the double rubber ring socket is provided with two independent sealing ring grooves spaced parallel to each other along the axial direction, and a pressure testing screw hole is radially opened on the cylindrical surface between the two sealing ring grooves. A removable sealing plug is installed in the pressure testing screw hole. When the double rubber ring socket is connected to the external PCCP pipe socket, the two sealing rubber rings, the outer wall of the socket and the inner wall of the PCCP pipe socket together form an independent sealed pressure testing chamber.

[0011] Beneficial effects: By combining two independent sealing ring grooves with sealing rubber rings, a double sealing structure can be formed, which improves the sealing redundancy under high-pressure water transmission conditions; by forming a closed pressure test chamber, the sealing performance of a single interface can be tested without relying on the entire pipeline, which facilitates the inspection of leakage risks at each port during construction and improves the overall sealing reliability of the pipeline network.

[0012] Furthermore, the PCCP adapter socket is a concave socket structure with a sealing groove inside, which is used to be compatible with external single-ring or double-ring PCCP pipes.

[0013] Beneficial effects: It can simultaneously connect single-ring and double-ring PCCP pipes, and can complete the connection without distinguishing the specific port type of the PCCP pipe. It is suitable for the renovation of old pipeline networks and non-standard pipeline connection scenarios, further expanding the port compatibility range of the connection components.

[0014] Furthermore, the metal pipe socket is a concave socket structure, with a limiting step and an annular rubber ring mounting groove arranged sequentially along the axial direction inside, for inserting the metal pipe into the socket and achieving a sealed connection.

[0015] Beneficial effects: When inserting metal pipe spigots, it can achieve precise axial positioning and stable radial sealing, ensuring the docking accuracy and sealing performance of the metal pipe side.

[0016] Furthermore, the metal tube socket has an externally inserted smooth cylindrical outer wall structure.

[0017] Beneficial effects: There is no need to set the rubber ring groove and seal on the connecting components themselves. The compression seal can be achieved by relying on the sealing rubber ring pre-installed inside the mating metal pipe socket. It can be directly inserted into the standard metal pipe socket, adapting to the scenarios of rapid connection and bidirectional conversion of pipeline network. The structure is simple and the on-site installation efficiency is high.

[0018] Furthermore, the metal flange has a circular disc surface perpendicular to the central reinforcing base, and a plurality of bolt through holes are uniformly formed along the circumference on the circular disc surface.

[0019] Beneficial effects: It can achieve rigid connection with various flanges, pipes, valves and equipment ports, with high connection strength and reliable sealing performance.

[0020] Furthermore, the overall material of the connecting component is ductile iron, and the PCCP mating end, the central reinforcing base and the metal pipe mating end are integrally cast using a sand casting process, and the whole component undergoes stress-relief annealing treatment after forming; or the overall material of the connecting component is carbon steel, and the PCCP mating end, the central reinforcing base and the metal pipe mating end are respectively processed and then assembled by segmented bevel welding, and the connecting component undergoes stress-relief annealing treatment and weld seam grinding and smoothing treatment after welding.

[0021] Beneficial effects: When using ductile iron, integral casting via sand casting followed by stress-relief annealing results in a seamless, integrated structure with excellent structural integrity, uniform and stable mechanical properties, suitable for mass production and with controllable manufacturing costs. When using carbon steel, each part is machined separately and then assembled by segmented beveling and full welding. Post-weld stress-relief annealing and smoothing of the weld seams effectively eliminate residual welding stress, improving the structural strength and quality stability of the weld area.

[0022] Furthermore, both the inner and outer walls of the connecting component are coated with an epoxy ceramic anti-corrosion coating, the thickness of which is not less than 200 μm.

[0023] Beneficial effects: It can form a uniform and dense protective layer on the surface of components, effectively improving the corrosion resistance of components, resisting the corrosion and erosion of soil environment and transport medium, extending the service life of components, and ensuring the long-term stable operation of pipeline network.

[0024] Furthermore, the connecting component is shaped as a straight short pipe, a bend, or a tee-type standard pipe fitting.

[0025] Beneficial effects: It can cover different pipeline layout scenarios such as straight connection, pipeline turning, and branch pipe diversion, and fully adapt to the heterogeneous pipeline docking needs of various water transmission projects. Attached Figure Description

[0026] Figure 1 This is an assembly diagram of the universal connection component for metal pipes and PCCP pipes of the present invention; Figure 2 A schematic diagram showing the mating of a PCCP connector using a single rubber ring. Figure 3 A schematic diagram showing the mating of a PCCP connector using a double rubber ring socket. Figure 4 A diagram illustrating the fit when a socket is used for the PCCP connector. Figure 1 ; Figure 5 A diagram illustrating the fit when a socket is used for the PCCP connector. Figure 2 ; Figure 6 A schematic diagram showing the fit of metal pipes when a socket is used at the joint end; Figure 7 A schematic diagram showing the fit when a flange is used at the joint end of a metal pipe; Figure 8 This is a schematic diagram showing the fit of a metal pipe when a spigot is used at the joint.

[0027] Explanation of reference numerals in the attached figures: 1. Central reinforced base; 2. PCCP mating end; 201. PCCP adapter single rubber ring spigot; 202. PCCP adapter double rubber ring spigot; 203. PCCP adapter socket; 204. Sealing ring groove; 205. Pressure testing screw hole; 3. Metal pipe mating end; 301. Metal pipe adapter socket; 302. Metal flange; 303. Metal pipe adapter spigot; 4. PCCP pipe; 5. PCCP socket; 6. PCCP single rubber ring spigot; 7. PCCP double rubber ring spigot; 8. PCCP rubber ring; 9. Metal pipe; 10. Metal pipe socket; 11. Metal pipe spigot; 12. Flange interface; 13. Metal pipe rubber ring. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0029] Embodiments of the universal connection component for metal pipes and PCCP pipes of the present invention: like Figure 1 As shown, the universal connecting component for metal pipes and PCCP pipes is a metal tubular structure consisting of three parts: a central reinforcing base 1, a PCCP docking end 2, and a metal pipe docking end 3. These three parts are connected sequentially along the axial direction.

[0030] The central reinforced base 1 serves as the main load-bearing structure, connecting the PCCP connector 2 and the metal pipe connector 3. It employs a thickened tubular structure design, with a wall thickness exceeding that of both the PCCP connector 2 and the metal pipe connector 3. This design aims to evenly distribute internal and external loads, enhancing the overall pressure-bearing capacity, bending resistance, and settlement load resistance of the connecting component. The PCCP connector 2 is used to connect with the external PCCP pipe 4, such as... Figure 2 , Figure 3 and Figure 4 As shown, three structural forms are available: PCCP adapter single rubber ring spigot 201, PCCP adapter double rubber ring spigot 202, or PCCP adapter socket 203. The metal pipe mating end 3 is used to connect with external metal pipes 9, such as... Figure 5 , Figure 6 and Figure 7 As shown, three structural forms can be selected: metal pipe socket 10, metal pipe spigot 11, or metal flange 302.

[0031] In actual production, based on the target connection scenario, one structure is selected from each end and combined with the central reinforcing base 1 to form a standard, fixed-size pipe fitting of the corresponding specifications. The forming process can be integral casting or segmented full welding assembly, and all components undergo overall stress-relieving annealing after forming. Both the inner and outer walls of the connecting components are coated with epoxy ceramic anti-corrosion coating to improve corrosion resistance.

[0032] The nominal diameter of the universal connecting component for metal pipes and PCCP pipes of the present invention covers DN100 to DN3000, and the design pressure rating is PN10, PN16, and PN25. Standardized products with corresponding specifications and pressure ratings can be selected according to the actual needs of the project. There is no need for on-site surveying, material cutting, and customized processing. Standardized mass production can be achieved, the products are highly interchangeable, effectively reducing the cost of project procurement and operation and maintenance, and shortening the supply cycle.

[0033] The following detailed explanation uses a typical combination of PCCP connector 2 and metal pipe connector 3 as an example.

[0034] Example 1 In this embodiment, the universal connecting component between the metal pipe and the PCCP pipe is a straight short pipe section. Specifically, the PCCP mating end 2 adopts... Figure 2 The PCCP adapter single rubber ring socket 201 shown is used for the metal tube mating end 3. Figure 6 The metal pipe shown is fitted with a 301 socket and is made of ductile iron through a sand casting process.

[0035] The central reinforcing base 1 is a straight, thickened circular tube structure with its axis extending in a straight line. The wall thickness of the central reinforcing base 1 is uniform and greater than that of the two end joints, which can evenly bear the internal water pressure and external soil load, avoid stress concentration at the two end joints, and ensure the overall structural strength and deformation resistance of the connecting components.

[0036] The PCCP connector 2 is integrally located at the left end of the central reinforcing base 1. It adopts a single rubber ring spigot structure, with a single sealing ring groove 204 circumferentially provided on the outer wall of the spigot. The sealing ring groove 204 is used to assemble a PCCP rubber ring 8. The outer diameter of the single rubber ring spigot is adapted to the inner diameter of the socket of the external single rubber ring PCCP pipe 4. During assembly, the PCCP adapter single rubber ring spigot 201 is inserted into the socket of the PCCP pipe 4. The PCCP rubber ring 8 is radially compressed and filled between the outer wall of the spigot and the inner wall of the socket, forming a stable radial seal.

[0037] The metal pipe mating end 3 is integrally set at the right end of the central reinforcing base 1, and adopts a metal pipe adapter socket 301. The metal pipe adapter socket 301 has a concave structure, and the interior is provided with a limiting step and an annular rubber ring mounting groove along the axial direction from the inside to the outside. The annular rubber ring mounting groove is used to assemble the metal pipe rubber ring 13. The inner diameter of the metal pipe adapter socket 301 is adapted to the outer diameter of the spigot of the external metal pipe 9. During assembly, the spigot of the metal pipe 9 is inserted into the interior of the metal pipe adapter socket 301, and the end of the spigot abuts against the limiting step to achieve axial positioning. The metal pipe rubber ring 13 is radially compressed and filled between the inner wall of the socket and the outer wall of the spigot to form a reliable sealing connection.

[0038] After the connecting component in this embodiment is integrally cast, it undergoes an overall stress-relief annealing treatment to eliminate residual internal stress generated during the casting process. Then, the inner and outer walls are cleaned and an epoxy ceramic anti-corrosion coating is sprayed on. The thickness of the epoxy ceramic anti-corrosion coating is not less than 200μm, forming a uniform and dense protective layer on the surface of the connecting component to resist corrosion and erosion from the soil environment and the transport medium.

[0039] During operation, the left end of the connecting component is sealed by inserting and connecting the PCCP adapter single rubber ring spigot 201 to the PCCP socket 5, while the right end is sealed by inserting and connecting the metal pipe adapter socket 301 to the metal pipe spigot 9. The central reinforcing base 1 bears the main load-bearing function, enabling a straight connection between two types of pipes made of different materials. The single-seal structure is suitable for conventional low-pressure water transmission scenarios. It has a simple structure, is easy to assemble, and can directly replace traditional non-standard customized pipe fittings, effectively simplifying on-site construction procedures and improving installation efficiency.

[0040] Example 2 In this embodiment, the universal connecting component between the metal pipe and the PCCP pipe is a straight short pipe section. The PCCP mating end 2 adopts... Figure 3 The PCCP adapter with double rubber ring socket 202 shown is used for metal tube mating end 3. Figure 7 The metal flange 302 shown is made of carbon steel and is assembled by full welding of segmented bevels.

[0041] The central reinforced base 1 is a straight, thickened circular tube structure with its axis extending in a straight line. The wall thickness is greater than that of the two ends where they meet, giving it high structural strength and resistance to deformation. It can withstand internal loads under high-pressure water transmission conditions.

[0042] The PCCP connector 2 is located at the left end of the central reinforcing base 1 and adopts a double rubber ring spigot structure. Two sealing ring grooves 204 are spaced parallel to each other along the axial direction on the outer wall of the spigot, and each of the two sealing ring grooves 204 is fitted with a PCCP rubber ring 8. A pressure-pressing screw hole 205 is radially opened on the cylindrical surface between the two sealing ring grooves 204, and a removable sealing plug is installed in the pressure-pressing screw hole 205. The outer diameter of the PCCP adapter double rubber ring spigot 202 matches the inner diameter of the socket of the external PCCP pipe 4. During assembly, the PCCP adapter double rubber ring spigot 202 is inserted into the socket of the PCCP pipe 4, and the two PCCP rubber rings 8 are radially compressed to form a double seal. The area between the two PCCP rubber rings 8, together with the outer wall of the spigot and the inner wall of the PCCP socket 5, forms an independent sealed pressure testing chamber.

[0043] The metal pipe mating end 3 is located at the right end of the central reinforcing base 1 and adopts a metal flange 302. The metal flange 302 has a circular disc surface perpendicular to the axis of the central reinforcing base 1, and several bolt through holes are evenly distributed along the circumference of the circular disc surface. The inner end face of the metal flange 302 is coaxially mated with the end of the central reinforcing base 1, and a fixed connection is achieved through a bevel full welding process to ensure the structural strength and sealing of the mating joint.

[0044] After each part of this embodiment is processed, it is coaxially aligned and fully welded with segmented bevels. After welding, the connecting components are subjected to stress-relief annealing to fully eliminate residual welding stress. Then, all welds are ground smooth, and epoxy ceramic anti-corrosion coating is sprayed on the inner and outer walls of the connecting components to ensure the corrosion resistance and appearance smoothness of the connecting components.

[0045] During operation, the left end of the connecting component forms a double seal by inserting the PCCP adapter double rubber ring spigot 202 into the PCCP socket 5. The right end is bolted to the external pipe, valve, or equipment port with flange interface 12 via metal flange 302, achieving a rigid connection. For interface sealing testing, the sealing plug can be removed, and test medium can be injected into the sealed test chamber through the pressure bolt hole 205 to test the sealing performance of the interface. The test pressure is controlled between 0.2 and 0.4 MPa, and the pressure holding time is no less than 5 minutes. Acceptance is complete once the specifications are met. Leak testing can be performed port by port without waiting for the entire pipeline to be connected. After identifying potential leaks, the sealing plug is retightened for normal use. The double-sealing structure provides higher sealing redundancy, is suitable for high-pressure water transmission scenarios, and the independent pressure testing function effectively improves construction and acceptance efficiency, reducing the cost and time impact of rework due to leaks.

[0046] Example 3 In this embodiment, the universal connecting component between the metal pipe and the PCCP pipe is a straight short pipe section, and the PCCP docking end 2 adopts... Figure 4 and Figure 5 The PCCP adapter socket 203 shown is used for the metal pipe mating end 3. Figure 8 The metal tube adapter socket 303 shown is made of ductile iron and cast in one piece.

[0047] The central reinforcing substrate 1 is a straight, thickened circular tube structure with a wall thickness greater than that of the two end joints. It serves as the central load-bearing body to evenly transfer the load and avoid stress concentration at the joint.

[0048] The PCCP connector 2 is integrally located at the left end of the central reinforcing base 1. It adopts a PCCP adapter socket 203 structure, which is a concave structure with a sealing groove inside. A sealing ring can be installed in the sealing groove. The inner diameter of the PCCP adapter socket 203 is compatible with the outer diameter of the external PCCP single-ring socket 6 or PCCP double-ring socket 7. During assembly, whether it is a single-ring or double-ring PCCP pipe 4 socket, it can be inserted into the adapter socket. A seal is formed by the compression of the sealing ring, and the connection can be completed without distinguishing the number of sealing rings at the port of the PCCP pipe 4.

[0049] The metal tube mating end 3 is integrally set at the right end of the central reinforcing base 1, and adopts a metal tube adapter socket 303. The metal tube adapter socket 303 is an externally inserted smooth cylindrical outer wall structure, and the outer wall does not have a rubber ring groove. The outer diameter of the metal tube adapter socket 303 is adapted to the inner diameter of the external standard metal tube socket 10. During assembly, the metal tube adapter socket 303 is inserted into the external metal tube socket 10, and a seal is formed by the compression of the sealing rubber ring pre-installed inside the metal tube socket 10.

[0050] In this embodiment, the connecting component is integrally cast and then subjected to stress-relieving annealing. The inner and outer walls are sprayed with an epoxy ceramic anti-corrosion coating to ensure the long-term performance of the component.

[0051] During operation, the left end of the connecting component is compatible with the spigot of PCCP pipe 4 with different port forms through PCCP adapter socket 203, and the right end is directly inserted into the standard metal pipe socket 10 through metal pipe adapter spigot 303. It is suitable for old pipeline renovation and connection scenarios with unclear port forms. The structure is simple, the on-site installation efficiency is high, and it can effectively shorten the project construction cycle and reduce the additional cost of non-standard adapters.

[0052] The above embodiments are only typical combinations of straight short pipe sections. In practical applications, the overall shape of the connecting components can also be set as a bend or a tee according to engineering requirements. When the central reinforcing base 1 is adjusted to an arc-shaped bend, the two ends can still be arbitrarily combined according to the above three forms to form a bend-shaped pipe fitting suitable for pipeline turning scenarios. When the central reinforcing base 1 is adjusted to a three-way intersection section, the ends of each branch can be configured with corresponding forms of connecting ends according to requirements to form a tee-shaped pipe fitting suitable for branch pipe diversion scenarios. The structural principles and working methods of various modified pipe fittings are consistent with those of the straight short pipe section and all fall within the protection scope of this invention.

[0053] Furthermore, since there are three different structures to choose from for the PCCP connector 2 and three different structures to choose from for the metal pipe connector 3, the universal connection component for metal pipes and PCCP pipes of the present invention includes a total of nine different structural forms. The above three embodiments only provide three specific structural forms of connecting pipe fittings. The other six forms can be combined in different ways according to engineering requirements. For example, they can be combined as follows: PCCP connector 2 is a PCCP adapter single rubber ring socket 201 and metal pipe connector 3 is a metal flange 302; PCCP connector 2 is a PCCP adapter single rubber ring socket 201 and metal pipe connector 3 is a metal pipe adapter socket 303; PCCP connector 2 is a PCCP adapter double rubber ring socket 202 and metal pipe connector 3 is a metal pipe adapter socket 301; PCCP connector 2 is a PCCP adapter double rubber ring socket 202 and metal pipe connector 3 is a metal pipe adapter socket 303; PCCP connector 2 is a PCCP adapter socket 203 and metal pipe connector 3 is a metal pipe adapter socket 301; PCCP connector 2 is a PCCP adapter socket 203 and metal pipe connector 3 is a metal flange 302. These will not be described in detail here.

[0054] While various embodiments of the invention have been shown and described in this specification, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Many modifications, alterations, and alternatives will occur to those skilled in the art without departing from the spirit and essence of the invention.

Claims

1. A universal connecting component for metal pipes and PCCP pipes, characterized in that, The whole is a metal tubular structure, including a PCCP docking end, a central reinforcing matrix and a metal tube docking end connected sequentially along the axial direction; The central reinforcing base is connected between the PCCP docking end and the metal pipe docking end. It is a thickened tubular load-bearing structure. The wall thickness of the central reinforcing base is greater than the wall thickness of the PCCP docking end and the metal pipe docking end. PCCP connectors are used to connect with external PCCP pipes. The structure of a PCCP connector can be any one of a single rubber ring socket, a double rubber ring socket, or a PCCP adapter socket. Metal pipe connectors are used to connect with external metal pipes. The structure of a metal pipe connector can be any one of a metal pipe socket, a metal pipe spigot, or a metal flange. The PCCP docking end and the metal pipe docking end are each pre-selected from three corresponding structures and combined with the central reinforcing base to form a standard pipe fitting adapted to specific heterogeneous pipe connection scenarios. The PCCP docking end, the central reinforcing base and the metal pipe docking end are integrally cast and subjected to integral stress-relief annealing after forming, or are combined by segmented full welding and subjected to integral stress-relief annealing after welding.

2. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The outer wall of the single rubber ring socket is provided with a single sealing ring groove for assembling a sealing rubber ring, which is suitable for the socket connection of the single rubber ring PCCP pipe.

3. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The outer wall of the double rubber ring socket is provided with two independent sealing ring grooves spaced parallel to each other along the axial direction. A pressure testing screw hole is opened radially on the cylindrical surface between the two sealing ring grooves. A removable sealing plug is installed in the pressure testing screw hole. When the double rubber ring socket is connected to the external PCCP pipe socket, the two sealing rubber rings, the outer wall of the socket and the inner wall of the PCCP pipe socket form an independent sealed pressure testing chamber.

4. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The PCCP adapter socket is a concave socket structure with a sealing groove inside, which is used to be compatible with external single-ring or double-ring PCCP pipes.

5. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The metal pipe socket is a concave socket structure, with a limiting step and an annular rubber ring mounting groove arranged sequentially along the axial direction inside, for inserting the metal pipe into the socket and achieving a sealed connection.

6. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The metal tube socket has an externally inserted, smooth cylindrical outer wall structure.

7. The universal connecting component for metal pipes and PCCP pipes according to claim 1, characterized in that, The metal flange has a circular disc surface perpendicular to the central reinforcing base, and a plurality of bolt through holes are evenly distributed along the circumference of the circular disc surface.

8. The universal connecting component for metal pipes and PCCP pipes according to any one of claims 1-7, characterized in that, The connecting component is made of ductile iron. The PCCP mating end, the central reinforcing base, and the metal pipe mating end are integrally cast using a sand casting process, and the entire component undergoes stress-relief annealing after forming. Alternatively, the connecting component is made of carbon steel. The PCCP mating end, the central reinforcing base, and the metal pipe mating end are processed separately and then assembled by segmented bevel welding. After welding, the entire connecting component undergoes stress-relief annealing and weld seam grinding.

9. The universal connecting component for metal pipes and PCCP pipes according to any one of claims 1-7, characterized in that, The inner and outer walls of the connecting component are coated with an epoxy ceramic anti-corrosion coating, and the thickness of the epoxy ceramic anti-corrosion coating is not less than 200μm.

10. The universal connecting component for metal pipes and PCCP pipes according to any one of claims 1-7, characterized in that, The connecting component is shaped as a straight short pipe, a bend, or a tee-type standard pipe fitting.

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