High-damping plastic sleeve for drainage jacking pipe and nodular cast iron composite pipe
By designing a composite pipe with a high-damping plastic sleeve and ductile iron, the problems of poor dynamic load adaptability, insufficient sealing and low production efficiency in drainage pipe jacking projects have been solved, achieving high fatigue life and high sealing performance of the composite pipe, and meeting the requirements of mechanized construction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-14
- Publication Date
- 2026-03-24
AI Technical Summary
In existing drainage pipe jacking projects, ductile iron pipes have poor dynamic load adaptability, insufficient sealing reliability, low production efficiency, and insufficient adhesion between the plastic sheath and the cast iron matrix, resulting in unoptimized damping performance.
The structure adopts a high-damping plastic sleeve and ductile iron composite pipe, including a filling layer, buffer pad and O-ring on the outside of the plastic sleeve, combined with a multi-layer anti-corrosion coating to form a double sealing system, which enhances the connection strength and sealing performance and improves the mechanical properties under dynamic load conditions.
It significantly improves the fatigue life and sealing performance of composite pipes, reduces the risk of leakage, increases production efficiency and service life, and meets the needs of mechanized pipe jacking construction.
Smart Images
Figure CN224033267U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to municipal drainage pipeline engineering technical field especially refers to a high damping plastic sleeve for drainage jacking pipe and nodular cast iron composite pipe. BACKGROUND
[0002] At present, the nodular cast iron pipe commonly used in drainage jacking pipe engineering mostly adopts concrete / cement sheath as outer protection, which has the following problems: firstly, poor dynamic load adaptability, the cement sheath is a rigid material, the damping coefficient is low, stress concentration is easy to produce under the action of vehicle load, soil displacement and other dynamic loads, leading to sheath cracking, anticorrosive layer peeling and unsatisfactory service life; secondly, insufficient sealing reliability, the traditional socket and spigot joint relies on rigid sealing ring, the axial displacement compensation capacity is weak, and the difference between the thermal expansion coefficients of the cement sheath and the sealing ring is large, leakage is easy to occur in long-term operation; thirdly, low production efficiency, the cement sheath needs on-site maintenance, the production cycle is long, and the interface docking precision is high, which is difficult to meet the demand of mechanized jacking pipe rapid construction. Although there is an attempt to use plastic sheath in the prior art, there are generally problems such as insufficient adhesion between plastic and cast iron matrix and non-optimization of damping performance for dynamic load environment. Therefore, a new jacking pipe structure with mechanical properties, durability and high production efficiency is urgently needed. SUMMARY
[0003] In view of the above problems, the utility model provides a high damping plastic sleeve for drainage jacking pipe and nodular cast iron composite pipe to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.
[0004] In order to achieve the above purpose, the utility model adopts the following technical scheme:
[0005] A high damping plastic sleeve for drainage jacking pipe and nodular cast iron composite pipe, comprising a pipe body and a plastic sleeve arranged on the outer side of the pipe body, a filling layer is filled in the gap between the pipe body and the plastic sleeve, the inner wall of the pipe body is coated with an anticorrosive cement protective layer, and the outer side of the plastic sleeve is coated with an anticorrosive coating, one end of the composite pipe is provided with a spigot joint, the other end is provided with a socket, adjacent composite pipes are connected through the spigot joint and the socket, and the spigot joint and the socket are interference fit, and the spigot joint is sleeved with a buffer pad and an O-shaped sealing ring.
[0006] Preferably, the pipe body is made of nodular cast iron.
[0007] Preferably, the plastic sleeve is made of high-density polyethylene or modified polypropylene.
[0008] Preferably, the filling layer material is anticorrosive cement or resin.
[0009] Preferably, the socket length of the spigot joint is greater than or equal to 20% of the pipe diameter.
[0010] Preferably, the buffer pad adopts a closed-cell type EPDM.
[0011] Preferably, the outer wall of the plastic sleeve is provided with a raised particle structure.
[0012] Preferably, the raised particle structure has a particle size of 0.5-1.5mm, a raised height of 0.3-0.8mm, and a surface roughness Ra of 3.2um or more.
[0013] The utility model has the advantages of:
[0014] 1. The utility model discloses a pipe body, a plastic sleeve and a filling layer filled between the pipe body and the plastic sleeve, which solve the technical problem of weak connection between the plastic sleeve and the pipe body in the prior art, improve the mechanical properties of the composite pipe in a dynamic load environment, greatly improve the fatigue life of the composite pipe under vibration load and reduce the risk of sealing failure.
[0015] 2. Compared with the traditional socket and spigot interface which relies on a rigid sealing ring and has weak axial displacement compensation ability, the socket head of the utility model is provided with a buffer pad and an O-shaped sealing ring, which improves the sealing performance of the pipe joint and effectively prevents leakage during operation.
[0016] 3. The maintenance time of the cement plastic sleeve is reduced, the production efficiency of the composite pipe is improved, and the whole cycle cost is lower than the cost of the existing cement plastic sleeve pipe body. BRIEF DESCRIPTION OF DRAWINGS
[0017] Fig. 1 is a schematic view of the embodiment;
[0018] Fig. 2 is a local enlarged view of A;
[0019] Marked as: 1, pipe body; 2, plastic sleeve; 3, filling layer; 4, anticorrosive coating; 5, spigot; 6, socket; 7, buffer pad; 8, O-shaped sealing ring; 9, anticorrosive cement protective layer. DETAILED DESCRIPTION
[0020] The technical scheme of the utility model will be described below in combination with the drawings and embodiments.
[0021] Embodiment: refer to Figs. 1-2The utility model discloses a high damping plastic sleeve and nodular cast iron composite pipe for drainage jacking pipe, including the pipe body 1, and the plastic sleeve 2 of setting in the pipe body 1 outside, the clearance of pipe body 1 and plastic sleeve 2 is filled with filling layer 3, when production and processing, because pipe body 1 adopts nodular cast iron, its surface is uneven, first, plastic sleeve 2 is set with the outside of pipe body 1, then through the mode of grouting, filling layer 3 is injected into the clearance of pipe body 1 and plastic sleeve 2, pipe body 1 inner wall coats anticorrosive cement protective layer 9, prevents pipe body 1 direct contact with the liquid circulation in pipeline, avoids rust corrosion. Plastic sleeve 2 outside coats anticorrosive coating 4, anticorrosive coating 4 includes three layers structure, from inside to outside is respectively: epoxy primer (thickness >= 50mu m) + polyurethane intermediate layer (thickness >= 150mu m) + polyethylene outer protective layer (thickness >= 1mm), total thickness >= 2.0mm, salt fog corrosion resistance >= 1000h, improves the anticorrosive ability of pipe fitting, and one end of composite pipe is equipped with the socket joint 5, and the other end is equipped with the socket 6, the socket joint 5 of one section of composite pipe is inserted in the socket of adjacent section of composite pipe 6, and socket joint 5 and socket 6 interference fit, the socket joint 5 is set with buffer pad 7 and O type sealing ring 8, and O type sealing ring hardness shore 70 plus or minus 5A, compression ratio 15%-20%, and buffer pad cooperates and forms multiple waterproof barriers, and its water pressure resistance >= 1.0MPa, in preferred scheme, socket length >= 20% pipe diameter, ensure that the connection between pipe fittings is tight, through the clearance of pipe body 1 and plastic sleeve 2 is filled with filling layer 3, improve the connection between pipe body 1 and plastic sleeve 2, plastic sleeve 2 effectively absorbs the stress in the construction process, improves the overall mechanical properties of composite pipe, in preferred scheme, buffer pad 7 is set on the outside and end of socket joint 5, buffer pad 7 adopts closed cell type EPDM, and the thickness is 10mm, and buffer pad 7 thickness 10mm, when jacking pipe jacking, absorbs more than 80% impact kinetic energy, greatly reduces the stress peak value at the interface from traditional design, eliminates the risk of stress corrosion cracking from the source.
[0022] Specifically, pipe body 1 adopts nodular cast iron, which has sufficient rigidity, and the manufacturing cost of nodular cast iron is lower than other steel materials, and the inner wall is coated with anticorrosive cement to ensure that the nodular cast iron is not eroded.
[0023] Specifically, plastic sleeve 2 is made of high-density polyethylene or modified polypropylene, and has a shore hardness of 65-75A and an elongation at break of greater than or equal to 300%. A maleic anhydride grafting compatibilizer with a mass fraction of 3%-5% is added to enhance the adhesion, so that the material can absorb 60%-70% of vibration energy under dynamic load, and the stress peak value is reduced by more than 60% compared with a rigid interface. A self-adapting socket sealing structure is formed.
[0024] Specifically, the filling layer 3 is made of anticorrosive cement or resin, which enhances the connection strength between the pipe body 1 and the plastic sleeve 2 and has a certain elasticity.
[0025] Specific, plastic sleeve 2 outer wall is provided with a raised particle structure (not shown in the figure), the raised particle structure particle size 0.5-1.5mm, the raised height 0.3-0.8mm, the surface roughness Ra is greater than or equal to 3.2 μm, the adhesion of ductile cast iron is greater than or equal to 5MPa, the connection of pipe body 1 and plastic sleeve 2 is improved, and the connection of plug joint 5 and socket 6 is improved.
[0026] The utility model has the following advantages:
[0027] 1. Dynamic load environment performance breakthrough, adopt double sealing system, first heavy seal: the physical seal formed by the interference fit of the inner wall of the plastic sleeve and the outer wall of the pipe body, the effective sealing life is equivalent to the service life of the plastic sleeve material; the second heavy seal: O-shaped sealing ring and buffer pad form a multi-channel waterproof barrier, the damping characteristics of the plastic sleeve make the fatigue life of the pipeline under vibration load improve by more than 3 times, and the risk of sealing failure is reduced by 80%.
[0028] 2. Full cycle durability improvement: multi-level corrosion prevention system makes the design, service life greater than or equal to 50 years, which is 60% longer than traditional cement sheathed pipeline;
[0029] 3. Revolutionary improvement of construction efficiency: mechanical pipe jacking single section installation time is less than or equal to 10 minutes, interface docking precision error is less than 0.5mm, and maintenance cycle is shortened from 72 hours to 2 hours.
[0030] In the description of the utility model, it is understood that the terms "upper", "lower", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a specific orientation, a specific orientation structure and operation, therefore, it cannot be understood as a limitation on the utility model. In addition, "first", "second" is only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more features. In the description of the utility model, unless otherwise specified, the meaning of "a plurality of" is two or more.
[0031] In the description of the utility model, it is necessary to point out that, unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.
[0032] The above has carried out the detailed description to one embodiment of the utility model, but the content described is only the preferred embodiment of the utility model, cannot be considered for limiting the implementation scope of the utility model. All equal changes and improvements etc. that are made in the utility model application scope should still belong to the patent coverage scope of the utility model.
Claims
1. A high-damping plastic sleeve and ductile cast iron composite pipe for a drainage pipe, comprising a pipe body (1) and a plastic sleeve (2) arranged on the outer side of the pipe body (1), characterized in that, The gap between the pipe body (1) and the plastic sleeve (2) is filled with a filling layer (3). The inner wall of the pipe body (1) is coated with an anti-corrosion cement protective layer (9). The outer side of the plastic sleeve (2) is coated with an anti-corrosion coating (4). One end of the composite pipe is provided with a plug (5) and the other end is provided with a socket (6). Adjacent composite pipes are connected by plug (5) and socket (6), and plug (5) and socket (6) are interference fit. The plug (5) is fitted with a buffer pad (7) and an O-ring (8).
2. The high-damping plastic sleeve and ductile cast iron composite pipe for a drainage pipe according to claim 1, characterized by The tube body (1) is made of ductile iron.
3. The high-damping plastic sleeve and ductile cast iron composite pipe for a drainage push pipe according to claim 1, characterized by, The plastic sleeve (2) is made of high-density polyethylene or modified polypropylene.
4. The high-damping plastic sleeve and ductile cast iron composite pipe for a drainage push pipe according to claim 1, characterized by The filler layer (3) is made of anti-corrosion cement or resin.
5. The high-damping plastic sleeve and ductile iron composite pipe for drainage jacking pipe according to claim 1, characterized in that, The insertion length of the connector (5) is ≥20% of the pipe diameter.
6. The high-damping plastic sleeve and ductile iron composite pipe for drainage jacking pipe according to claim 1, characterized in that, The buffer pad (7) is made of closed-cell EPDM rubber.
7. The high-damping plastic sleeve and ductile iron composite pipe for drainage jacking pipe according to claim 1, characterized in that, The outer wall of the plastic sleeve (2) is provided with a raised particle structure.
8. The high-damping plastic sleeve and ductile iron composite pipe for drainage jacking pipe according to claim 7, characterized in that, The protruding particle structure has a particle size of 0.5-1.5 mm, a protrusion height of 0.3-0.8 mm, and a surface roughness Ra≥3.2 μm.