Unbonded rib steel strand replacing device with pressure oil injection function

Abstract

The utility model discloses an unbonded rib steel strand replacing device with pressure oil injection, belongs to the technical field of unbonded prestressed systems, and solves the problem that an unbonded rib steel strand in an existing prestressed anchoring system cannot be replaced or is difficult to replace. The device comprises a traction machine and an oiling machine, the traction machine is provided with a traction steel strand, the traction steel strand is connected with one end of a to-be-replaced steel strand in the unbonded rib through a detachable connector, the other end of the to-be-replaced steel strand is connected with a new steel strand through a detachable connector, and the new steel strand is connected with the oiling machine. The outer diameter of the connector is not larger than that of the steel strand to be replaced, the front end of the PE sleeve in the unbonded rib is wrapped with a detachable sealing device, and the sealing device is communicated with an oiling machine. According to the unbonded rib steel strand replacing device, the problem that the unbonded rib steel strand in a prestress anchoring system cannot be replaced or is difficult to replace is solved, and the life cycle of the prestress system is effectively prolonged.

Description

Technical Field

[0001] This utility model relates to the technical field of unbonded prestressed systems, and more specifically, it relates to a device for replacing unbonded reinforcing steel strands with pressure oil injection. Background Technology

[0002] Currently, prestressed anchorage systems are mainly divided into bonded and unbonded systems. Bonded anchorage systems use grouting to bond the steel strands to the structure, forming a structural whole. Unbonded anchorage systems use unbonded reinforcement bars, with grease filling the outer PE sleeve of the bars, allowing the steel strands to slide within the PE sleeve and achieving lower friction loss. However, conventional unbonded reinforcement bars need to be poured together with the concrete, which has a significant impact on large components or components cast in sections. In summary, bonded prestressed systems have high friction loss, while unbonded systems are inconvenient to construct.

[0003] In the field of civil engineering, particularly in the field of prestressed containment technology for third-generation nuclear power plants, the use of unbonded prestressing systems can reduce the frictional resistance of prestressed strands, increase the effective prestress within components, and shorten the construction cycle of nuclear power plants. During the operational life of the components, if steel strand slack occurs, the prestressed strands can be tensioned again, extending the lifespan of the containment.

[0004] However, over time during operation, steel strands gradually loosen due to the material's properties, causing the components to lose their original mechanical properties. Furthermore, within their lifespan, steel strands may break due to overloading or inherent defects, posing safety hazards. Therefore, how to replace unbonded steel strands has become a pressing problem that needs to be solved. Utility Model Content

[0005] The technical problem to be solved by this utility model is to address the above-mentioned shortcomings of the prior art. The purpose of this utility model is to provide a pressure-injected oil replacement device for unbonded steel strands, which solves the problem that unbonded steel strands in prestressed anchorage systems cannot be replaced or are difficult to replace, and effectively extends the life cycle of the prestressed system.

[0006] To achieve the above objectives, this utility model provides a pressure-injected oil-filled unbonded steel strand replacement device, comprising a traction machine and an oil-filling machine. The traction machine is equipped with a traction steel strand, which is connected to one end of the steel strand to be replaced in the unbonded rib via a detachable connector. The other end of the steel strand to be replaced is connected to a new steel strand via a detachable connector. The outer diameter of the connector is not greater than the outer diameter of the steel strand to be replaced. The front end of the PE sleeve in the unbonded rib is wrapped with a detachable sealing device, which is connected to the oil-filling machine.

[0007] As a further improvement, the connector includes a two-part cylindrical body with grooves inside, and both ends of the cylindrical body are threaded with tightening nuts.

[0008] Furthermore, the connector is provided with a rubber ring, the outer diameter of which is larger than the inner diameter of the PE sleeve in the unbonded rib.

[0009] Furthermore, the sealing device includes a hollow sealing cylinder with an inner diameter larger than the outer diameter of the new steel strand. One end of the sealing cylinder is provided with a first sealing structure to clamp and seal the new steel strand, and the other end is provided with a second sealing structure to clamp and seal the end of the PE sleeve in the unbonded rib. The sealing cylinder is connected to the oil injection machine.

[0010] Furthermore, the sealing cylinder is provided with an oil inlet pipe and an oil return pipe, which are respectively connected to the oil outlet and oil return port of the oil injector, and a pressure valve is provided on the oil inlet pipe or the oil return pipe.

[0011] Furthermore, the first sealing structure includes a sealing cap and a hollow sealing plug. One end of the sealing cylinder has a tapered hole, and the sealing plug is inserted into the tapered hole. The sealing cap is detachably installed at one end of the sealing cylinder. When the sealing cap is in a tightened state, its inner surface axially presses the sealing plug to deform the sealing plug and clamp and seal the new steel strand.

[0012] Furthermore, the sealing plug has a conical structure, and at least one protruding rib is provided on the end face of the sealing plug near the sealing cap and on the side face of the sealing plug.

[0013] Furthermore, the inner wall of the sealing plug is provided with a spiral groove that matches the spiral of the steel strand.

[0014] Furthermore, the second sealing structure includes a sealing tube with an inner diameter smaller than that of the sealing cylinder. The sealing tube is connected to the sealing cylinder, and at least one sealing ring is provided on the inner wall of the end of the sealing tube away from the sealing cylinder.

[0015] Furthermore, there are multiple sealing rings, which are installed side by side in the sealing ring grooves opened in the inner wall of the sealing tube, and the diameter of the sealing ring grooves corresponding to the multiple sealing rings gradually decreases along one end of the sealing tube.

[0016] Beneficial effects

[0017] Compared with the prior art, the advantages of this utility model are as follows:

[0018] 1. The unbonded steel strand replacement device of this utility model solves the problem that the unbonded steel strand in the prestressed anchorage system cannot be replaced or is difficult to replace, and effectively extends the life cycle of the prestressed system.

[0019] 2. The non-bonded steel strand replacement device of this utility model injects grease into the sealing device through an oiling machine, which can fill the surface of the new steel strand and the gaps between the steel wires with grease, ensuring the grease content of the replaced non-bonded strand and improving the anti-corrosion performance; at the same time, it makes the traction of the new steel strand into the PE sleeve smoother, further improving construction efficiency and reducing the damage of the steel strand to the PE sleeve.

[0020] 3. The non-adhesive steel strand replacement device of this utility model adopts the method of axially pressing the sealing plug with the sealing cover and pressing it with the conical hole of the sealing cylinder, so that the sealing plug is deformed and clamps the new steel strand to achieve a seal. This method can greatly improve the sealing effect and make construction more convenient.

[0021] 4. The non-adhesive steel strand replacement device of this utility model has a sealing plug with a conical structure. The conical end of the sealing plug extends into the cavity of the sealing cylinder. The grease in the cavity can provide a certain pressure, causing the conical end of the sealing plug to deform towards the steel strand, resulting in a better sealing effect. At the same time, the sealing plug adopts a spiral groove inner hole structure, which can fit the cross-sectional shape of the steel strand well, and the sealing plug can effectively seal the steel strand, resulting in a better sealing effect.

[0022] 5. The non-adhesive reinforcing steel strand replacement device of this utility model has several sealing ring grooves set at the front end of the sealing tube for installing the sealing ring. As the sealing tube is inserted, the sealing ring is compressed. The sealing ring is sealed by the sealing tube pressing forward. The inner diameter of the sealing ring groove gets smaller as it goes in, which can accommodate PE sleeves of different diameters. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure when the present invention is applied;

[0024] Figure 2 for Figure 1 A magnified schematic diagram of the structure at point A in the middle.

[0025] Figure 3 for Figure 2 Enlarged structural diagram at point B;

[0026] Figure 4 This is an enlarged schematic diagram of the sealing cylinder structure in this utility model;

[0027] Figure 5 This is an enlarged schematic diagram of the main view of the sealing plug in this utility model;

[0028] Figure 6 This is an enlarged side view of the sealing plug in this utility model;

[0029] Figure 7 This is an enlarged schematic diagram of the sealing tube structure in this utility model;

[0030] Figure 8 This is an enlarged schematic diagram of the connector structure in this utility model.

[0031] Among them: 1-traction machine, 2-oil injector, 3-traction steel strand, 4-connector, 5-steel strand to be replaced, 6-new steel strand, 7-sealing device, 8-PE sleeve, 9-rubber ring, 41-cylinder, 42-groove, 43-tightening nut, 71-sealing cylinder, 72-oil inlet pipe, 73-oil return pipe, 74-sealing cover, 75-sealing plug, 76-sealing pipe, 77-sealing ring, 711-conical hole, 751-protruding rib, 752-spiral groove, 761-sealing ring groove. Detailed Implementation

[0032] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.

[0033] See Figure 1-8 This invention relates to a pressure-injected oil-replacement device for unbonded steel strands, comprising a traction machine 1 and an oil injection machine 2. The traction machine 1 has a traction steel strand 3. When the traction machine 1 is started, the traction steel strand 3 is wound up. The traction steel strand 3 is connected to one end of the steel strand 5 to be replaced in the unbonded rib via a detachable connector 4. The other end of the steel strand 5 to be replaced is connected to a new steel strand 6 via the detachable connector 4. The outer diameter of the connector 4 is not greater than the outer diameter of the steel strand 5 to be replaced, ensuring that the connector 4 can pass through the PE sleeve 8 in the unbonded rib. A detachable sealing device 7 is wrapped around the front end of the PE sleeve 8 in the unbonded rib. The sealing device 7 is connected to the oil injection machine 2 to inject oil into the new steel strand 6.

[0034] The unbonded steel strand replacement device of this utility model injects grease into the sealing device 7 through the grease injector 2, which can fill the surface of the new steel strand and the gaps between the steel wires with grease, ensuring the grease content of the new unbonded strand and improving the anti-corrosion performance; at the same time, it makes the traction of the new steel strand into the PE sleeve smoother, further improving the construction efficiency and reducing the damage of the steel strand to the PE sleeve.

[0035] Preferred, such as Figure 8 As shown, the connector 4 includes a two-part cylindrical body 41. A groove 42 is provided inside the cylindrical body 41. The groove 42 is either a through hole or a blind hole. Both ends of the cylindrical body 41 are threaded with tightening nuts 43. After the center wire of the steel strand is bent, the two-part cylindrical body 41 is placed over the center wire, causing the bent wire to fall into the groove 42. Then, the tightening nuts 43 are tightened to achieve quick connection of the steel strands. Furthermore, the connector 4 is provided with a rubber ring 9, at least one of which has an outer diameter larger than the inner diameter of the PE sleeve 8 in the unbonded rib. Specifically, the outer diameter of the rubber ring 9 is 1-3 mm larger than the inner diameter of the PE sleeve 8.

[0036] In this embodiment, connector 4 can connect two sections of steel strand. By adding a rubber ring 9 with an outer diameter slightly larger than the inner diameter of the PE sleeve 8 to connector 4, as much old grease as possible is carried out during the replacement of the steel strand and replaced with new grease, which can better protect the steel strand for a long time.

[0037] Preferred, such as Figure 2 As shown, the sealing device 7 includes a hollow sealing cylinder 71. The inner diameter of the sealing cylinder 71 is larger than the outer diameter of the new steel strand 6, allowing a certain amount of grease to be temporarily stored in the sealing cylinder 71. A first sealing structure is provided at one end of the sealing cylinder 71 to clamp and seal the new steel strand 6, and a second sealing structure is provided at the other end to clamp and seal the end of the PE sleeve 8 in the unbonded rib, forming a closed cavity inside the sealing cylinder 71. During the oil injection process, a stable pressure can be maintained, allowing the grease to better enter the PE sleeve 8. The sealing cylinder 71 is connected to the oil injection machine 2. An oil inlet pipe 72 and an oil return pipe 73 are provided on the sealing cylinder 71, respectively connected to the oil outlet and oil return port of the oil injection machine 2, to supply oil to the sealing cylinder 71. A pressure valve (not shown in the figure) is provided on the oil inlet pipe 72 or the oil return pipe 73 to ensure that the grease in the sealing device 7 maintains a certain pressure. Furthermore, the first sealing structure includes a sealing cap 74 and a hollow sealing plug 75. A tapered hole 711 is provided at one end of the sealing cylinder 71, with the largest end of the tapered hole 711 facing the outside of the sealing cylinder 71. The sealing plug 75 is inserted into the tapered hole 711. The sealing cap 74 is detachably installed at one end of the sealing cylinder 71. Specifically, the sealing cap 74 can be connected to the sealing cylinder 71 by threads or screws. In this embodiment, a threaded connection is preferred, which is more convenient to operate. When the sealing cap 74 is in a tightened state, its inner surface axially presses the sealing plug 75 to deform the sealing plug 75 and clamp and seal the new steel strand 6.

[0038] The unbonded steel strand replacement device of this embodiment uses a sealing cap 74 to axially compress the sealing plug 75, and cooperates with the conical hole 711 of the sealing cylinder 71 to compress it, so that the sealing plug 75 deforms and clamps the new steel strand 6 to achieve a seal. This method can greatly improve the sealing effect and make construction more convenient.

[0039] Preferably, the sealing plug 75 has a conical structure, and at least one protruding rib 751 is provided on the end face of the sealing plug 75 near the sealing cover 74 and on the side of the sealing plug 75, so as to reduce the contact area, reduce the friction, and make the sealing plug 75 rotate more smoothly along the steel strand.

[0040] Preferably, since the steel strand is made of multiple steel wires spirally wound together, the inner wall of the sealing plug 75 is provided with a spiral groove 752 that matches the spiral of the steel strand. When the sealing plug 75 clamps the steel strand, the steel wires on the surface of the steel strand are embedded in the spiral groove 752, so that the steel strand fits tightly with the inner hole of the sealing plug 75, reducing the gap. When the steel strand and the sealing plug 75 move relative to each other, the sealing plug 75 can rotate freely, always achieving a seal and further improving the sealing effect.

[0041] In this embodiment, the sealing plug 75 adopts a conical structure. The conical end of the sealing plug 75 extends into the cavity of the sealing cylinder 71. The grease in the cavity can provide a certain pressure, causing the conical end of the sealing plug 71 to deform towards the steel strand, resulting in a better sealing effect. At the same time, the sealing plug adopts a spiral groove inner hole structure, which can fit the cross-sectional shape of the steel strand well, and the sealing plug can seal the steel strand well, resulting in a better sealing effect.

[0042] Preferably, the second sealing structure includes a sealing tube 76, the inner diameter of which is smaller than the inner diameter of the sealing cylinder 71. The sealing tube 76 is connected to the sealing cylinder 71. Specifically, the sealing tube 76 and the sealing cylinder 71 can be connected by threads or screws. In this embodiment, a threaded connection is preferred for easier operation. In this embodiment, the sealing cylinder 71 is connected to the PE sleeve 8 of the unbonded rib 6 through the sealing tube 76, keeping the sealing cylinder 71 away from the steel strand 5 to be replaced, avoiding interference and facilitating construction. At least one sealing ring 77 is provided on the inner wall of the end of the sealing tube 76 away from the sealing cylinder 71 to ensure sealing. Further, there are multiple sealing rings 77, which are installed side by side in the sealing ring grooves 761 opened on the inner wall of the sealing tube 76, and the diameter of the sealing ring grooves 761 corresponding to the multiple sealing rings 77 gradually decreases along one end of the sealing cylinder 71.

[0043] In this embodiment, several sealing ring grooves 761 are provided at the front end of the sealing tube 76 to install the sealing ring 77. As the sealing tube 76 is inserted, the sealing ring 77 is compressed. The sealing ring 77 is sealed by the sealing tube 76 pressing forward. The inner diameter of the sealing ring groove 761 becomes smaller as it goes in, so it can accommodate PE sleeves of different diameters.

[0044] In other embodiments, the first sealing structure and the second sealing structure can also be independent sealing rings. When the sealing cylinder 71 is fitted onto the new steel strand 6, the sealing ring can directly press against the new steel strand 6 and the PE sleeve for sealing. Obviously, the sealing cap, sealing plug, and sealing tube structure in this embodiment provides a better sealing effect.

[0045] Preferably, the end of the sealing tube 76 away from the sealing cylinder 71 is a flared opening to facilitate the insertion of the steel strand.

[0046] The construction process of this unbonded reinforcing steel strand replacement device is as follows:

[0047] S1. Release the unbonded prestressed tendons and remove the anchor plates and wedges at both ends of the prestressed tendons;

[0048] S2. Insert the sealing device 7 onto the new steel strand 6 and connect the sealing device 7 to the oil injection machine 2;

[0049] S3. Securely connect the new steel strand 6 to the steel strand 5 to be replaced, and the traction steel strand 3 of the traction machine 1 to the steel strand 5 to be replaced.

[0050] S4. Seal and connect the other end of the sealing device 7 to the PE sleeve 8 in the unbonded rib, and at the same time seal and connect one end of the sealing device 7 to the new steel strand 6.

[0051] S5. Start the grease injector 2 until the sealing device 7 is full of grease, and maintain an injection pressure of 0.1 to 20 bar.

[0052] S6. Start the traction machine 1 to pull out the steel strand 5 to be replaced until the new steel strand 6 completely replaces the steel strand 5 to be replaced. Remove the sealing device 7, disconnect the connection between the new steel strand 6 and the steel strand 5 to be replaced, and between the traction steel strand 3 and the steel strand 5 to be replaced, and cut off the new steel strand 6.

[0053] S7. Install the anchors at both ends and tension and anchor the new steel strand 6 to complete the replacement of the unbonded steel strand.

[0054] Step S2 includes the following specific steps:

[0055] S2.1. Place the sealing cap 74 and sealing plug 75 onto the new steel strand 6 in sequence, then place the sealing cylinder 71 onto the new steel strand 6, then place the sealing tube 76 onto the new steel strand 6, and connect and fix the sealing tube 76 to the sealing cylinder 71.

[0056] S2.2 Connect the oil inlet pipe 72 and the oil return pipe 73 to the oil outlet and oil return port of the oil injector 2, respectively.

[0057] Step S3 includes the following specific steps:

[0058] S3.1. Remove a certain length of the outer wire of the new steel strand 6 and tuck the center wire. Treat the steel strand 5 to be replaced in the same way. Pull the steel strand 3.

[0059] S3.2. Securely connect the new steel strand 6 to the steel strand 5 to be replaced and the traction steel strand 3 to the steel strand 5 to be replaced using connector 4.

[0060] Step S4 includes the following specific steps:

[0061] S4.1. Push the sealing cylinder 71 toward one end of the steel strand 5 to be replaced until the second sealing structure is fitted onto the PE sleeve 8 in the unbonded rib. When the second sealing structure is fitted onto the PE sleeve 8 in the unbonded rib, the sealing ring 77 and the PE sleeve 8 are interference fit to form a seal.

[0062] S4.2 Connect the sealing cover 74 to the sealing cylinder 71. The sealing cover 74 moves axially to squeeze the sealing plug 75, and the sealing plug 75 is deformed under the pressure of the conical hole 711, so that the sealing plug 75 clamps the new steel strand 6 to form a seal.

[0063] This utility model provides a replacement device for unbonded steel strands, which solves the problem of unbonded steel strands in prestressed anchorage systems being unable to be replaced or difficult to replace, and effectively extends the lifespan of the prestressed system.

[0064] The above are merely preferred embodiments of this utility model. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model, and these will not affect the implementation effect of this utility model or the practicality of the patent.

Claims

1. A device for replacing a non-bonded steel strand with pressure- injected oil, characterized in that The utility model provides a kind of steel strand replacement device, including traction machine (1) and oil injection machine (2), traction steel strand (3) is equipped on the traction machine (1), traction steel strand (3) is connected with the one end of the steel strand (5) to be replaced in unbonded tendon by detachable connector (4), the other end of the steel strand (5) to be replaced is connected with new steel strand (6) by detachable connector (4), the outer diameter of connector (4) is not greater than the outer diameter of steel strand (5) to be replaced, the front end of PE cover (8) in unbonded tendon is wrapped with detachable sealing device (7), and the sealing device (7) is communicated with oil injection machine (2).

2. The device for replacing non-bonded steel strand according to claim 1, wherein, The connector (4) includes a two-half barrel (41), the barrel (41) is provided with a mound groove (42), and the both ends of the barrel (41) are threadedly connected with a screw nut (43).

3. The device for replacing non-bonded steel strand according to claim 1, wherein, The connector (4) is provided with a rubber ring (9), and the outer diameter of the rubber ring (9) is greater than the inner diameter of the PE cover (8) in the unbonded tendon.

4. The device for replacing non-bonded steel strand according to claim 1 or 2 or 3, characterized in that, The sealing device (7) includes a hollow sealing cylinder (71), the inner diameter of the sealing cylinder (71) is greater than the outer diameter of the new steel strand (6), one end of the sealing cylinder (71) is provided with a first sealing structure for clamping and sealing the new steel strand (6), and the other end is provided with a second sealing structure for clamping and sealing the end of the PE cover (8) in the unbonded tendon, and the sealing cylinder (71) is communicated with the oil injection machine (2).

5. The device for replacing non-bonded steel strand according to claim 4, wherein, The sealing cylinder (71) is provided with an oil inlet pipe (72) and an oil return pipe (73) which are respectively communicated with the oil outlet and the oil return port of the oil injection machine (2), and the oil inlet pipe (72) or the oil return pipe (73) is provided with a pressure valve.

6. The device for replacing non-bonded steel strand according to claim 4, wherein, The first sealing structure includes a sealing cover (74) and a hollow sealing plug (75), the sealing cylinder (71) is provided with a tapered hole (711) at one end, the sealing plug (75) is inserted into the tapered hole (711), and the sealing cover (74) is detachably mounted at one end of the sealing cylinder (71), and in the fastened state, the inner side of the sealing cover (74) axially extrudes the sealing plug (75) to deform the sealing plug (75) to clamp and seal the new steel strand (6).

7. The device for replacing a non-bonded steel strand according to claim 6, characterized in that The sealing plug (75) is a tapered structure, and at least one protruding rib (751) is arranged on the end face of the sealing plug (75) close to the sealing cover (74) and the side face of the sealing plug (75).

8. The device for replacing non-bonded steel strand according to claim 6, wherein, The inner wall of the sealing plug (75) is provided with a spiral groove (752) matched with the spiral wire of the steel strand.

9. The device for replacing non-bonded steel strand according to claim 4, wherein, The second sealing structure includes a sealing pipe (76), the inner diameter of the sealing pipe (76) is smaller than the inner diameter of the sealing cylinder (71), the sealing pipe (76) is communicated with the sealing cylinder (71), and at least one sealing ring (77) is arranged on the inner wall of the end of the sealing pipe (76) away from the sealing cylinder (71).

10. The device for replacing a non-bonded steel strand according to claim 9, characterized in that, There are multiple sealing rings (77), and multiple sealing rings (77) are arranged in parallel in the sealing ring groove (761) formed in the inner wall of the sealing pipe (76), and the diameters of the corresponding sealing ring grooves (761) of multiple sealing rings (77) gradually decrease along one end of the sealing cylinder (71).

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