An axial cold extruded sleeve having a grip on cement

Abstract

This utility model discloses an axially cold-extruded sleeve with cement gripping force, belonging to the field of engineering structural connection technology. The cold-extruded sleeve is an integrally formed structure, including an outer sleeve layer, an inner sleeve layer coaxially disposed inside the outer sleeve layer, and protruding ribs integrally formed on the outer peripheral wall of the outer sleeve layer. Multiple protruding ribs are evenly spaced along the circumference of the outer sleeve layer and extend axially. When the sleeve is placed in cement, after the cement solidifies, a strong mechanical interlocking force is formed between the protruding ribs and the cement. Simultaneously, the protruding ribs increase the contact area between the sleeve and the cement, synergistically enhancing the gripping force. This utility model, by setting protruding ribs on the outer sleeve layer, solves the problem in the prior art where the smooth outer surface of the sleeve leads to insufficient gripping force with cement, making it prone to slippage and separation under axial force. This enhances the reliability of the connection and the overall stability of the structure, while its integrally formed structure also ensures its high mechanical strength.

Description

Technical Field

[0001] This utility model relates to the field of engineering structure connection technology, and in particular to an axial cold extrusion sleeve that has a gripping force with cement. Background Technology

[0002] In civil engineering fields such as buildings, bridges, and tunnels, reliable connections are required between precast components and cast-in-place concrete or cementitious substrates to ensure the mechanical properties and overall stability of the entire structure. Cold extrusion connection technology is widely used for connecting reinforcing bars or embedded parts due to its advantages such as high construction efficiency and strong connection strength. In this connection method, cold extrusion sleeves are typically used to connect the embedded components or reinforcing bars to the cementitious substrate.

[0003] However, existing cold-extruded sleeve products typically have a relatively smooth cylindrical outer surface. When such sleeves are embedded in a cement matrix and the cement has hardened, the bonding force between the sleeve and the cement relies mainly on the adhesion of the cement slurry and limited friction. In practical engineering applications, structures are subjected to various axial loads during service, such as tensile or compressive forces. Under these axial loads, the bond strength between the smooth sleeve surface and the cement is often insufficient to resist large shear stresses, leading to the risk of relative slippage or even complete separation of the sleeve from the cement. This slippage and separation not only reduces the reliability of the connection but also triggers structural failures, posing a potential threat to the stability and safety of the entire project.

[0004] Therefore, this utility model proposes an axial cold extrusion sleeve with gripping force with cement to solve the problem of insufficient gripping force between the cold extrusion sleeve and the cement matrix in the prior art, which easily leads to slippage and separation. Utility Model Content

[0005] To overcome the above deficiencies, this utility model provides an axial cold extrusion sleeve with gripping force with cement, aiming to improve the structural defects of existing axial cold extrusion sleeve products, which have relatively smooth outer surfaces, resulting in insufficient gripping force with the cement matrix and easy slippage and separation under axial force.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: an axial cold extrusion sleeve with gripping force with cement, comprising: an outer sleeve layer, an inner sleeve layer, and a rib, wherein the outer sleeve layer and the inner sleeve layer together constitute the main structure of the cold extrusion sleeve, wherein the inner sleeve layer is coaxially disposed inside the outer sleeve layer, and the outer sleeve layer, the inner sleeve layer, and the rib are integrally formed to constitute the cold extrusion sleeve, ensuring the overall mechanical strength and structural integrity of the cold extrusion sleeve; The ribs are integrally formed on the outer peripheral wall of the outer layer of the sleeve. There is no gap between the ribs and the outer peripheral wall of the outer layer of the sleeve. The ribs extend along the axial direction of the outer layer of the sleeve, and multiple ribs are evenly spaced along the circumference of the outer layer of the sleeve. The ribs increase the contact area between the cold extruded sleeve and the cement matrix, and after the cement solidifies, they form a strong mechanical interlocking effect with the cement, thereby enhancing the anti-slipping ability of the cold extruded sleeve during axial stress.

[0007] Preferably, the cross-sectional shape of the rib is trapezoidal, and the hypotenuse of the trapezoid can form a hook-shaped locking angle, further enhancing the interlocking effect with the cement and preventing minor slippage under stress.

[0008] Preferably, the cross-sectional shape of the rib is rectangular. Rectangular structures are simple, easy to process and form, and can also provide sufficient contact surface and biting force.

[0009] Preferably, the ribs are spirally arranged around the outer peripheral wall of the outer layer of the sleeve, which not only provides strong axial gripping force, but also resists torsional loads to a certain extent.

[0010] Preferably, the inner peripheral wall of the inner layer of the sleeve is provided with threads.

[0011] Preferably, the thread is an internal thread, and the engagement of the thread can ensure the reliability of the transmission of axial force between the cold extrusion sleeve and the connected component.

[0012] Preferably, the axial end of the cold-extruded sleeve is chamfered.

[0013] Preferably, the chamfer is provided on the outer periphery of the axial end of the cold extrusion sleeve to form a smooth transition surface, which facilitates the smooth insertion of the cold extrusion sleeve into the cement matrix during construction and reduces insertion resistance.

[0014] This utility model has the following beneficial effects: 1. This utility model solves the problem in the prior art that the smooth outer surface of the sleeve leads to insufficient gripping force with cement, and easy slippage and separation under stress, by setting an integrally formed rib on the outer peripheral wall of the cold extrusion sleeve. It achieves the effect of forming a tight mechanical interlock with cement through the rib, which significantly enhances the connection reliability and structural stability. 2. This utility model solves the problem of stress concentration or weak connection points in traditional split or post-processed structures by integrating the outer layer, inner layer and rib of the sleeve into an integral structure. It achieves the effect of improving the mechanical strength and structural integrity of the cold extruded sleeve and ensuring that it can withstand high-intensity construction pressure and subsequent loads. Attached Figure Description

[0015] Figure 1 This is a three-dimensional schematic diagram of an axial cold extrusion sleeve that has a gripping force with cement, as proposed in this utility model. Figure 2 This is a side view of an axial cold-extruded sleeve with gripping force with cement, as proposed in this utility model.

[0016] Legend: 1. Cold extrusion sleeve; 101. Outer layer of sleeve; 102. Inner layer of sleeve; 2. Raised rib. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] Reference Figure 1 and Figure 2 This utility model provides an embodiment of an axial cold-extruded sleeve with gripping force with cement, comprising an outer sleeve layer 101 and an inner sleeve layer 102 coaxially disposed inside the outer sleeve layer 101. The outer sleeve layer 101, the inner sleeve layer 102, and the protruding ribs 2 are integrally formed to constitute a cold-extruded sleeve 1. The cold-extruded sleeve 1 serves as the main body of a structural connector, used to achieve a firm connection between the component and the cement matrix. The outer sleeve layer 101 constitutes the outer structure of the cold-extruded sleeve 1 and is the main interface that directly contacts the cement and generates gripping force. The inner sleeve layer 102 forms the internal cavity of the cold-extruded sleeve 1, used to connect the cold-extruded component, such as connecting reinforcing bars or other connectors. The outer sleeve layer 101 and the inner sleeve layer 102 are fixedly connected by integral forming to ensure cold extrusion. The overall mechanical strength and structural stability of the sleeve 1 enable it to effectively resist external loads during axial cold extrusion construction and subsequent stress processes, achieving a firm connection of the components. The ribs 2 are integrally formed on the outer peripheral wall of the outer layer 101 of the sleeve, and there is no gap between the ribs 2 and the outer peripheral wall of the outer layer 101 of the sleeve. The ribs 2 extend along the axial direction of the outer layer 101 of the sleeve, and multiple ribs 2 are evenly spaced along the circumference of the outer layer 101 of the sleeve. The ribs 2 are the structure that achieves a firm grip with cement, which significantly increases the contact area between the cold extrusion sleeve 1 and the cement. After the cement solidifies, it will completely wrap and fill the gaps between the ribs 2, forming a tight mechanical interlocking effect, thereby effectively preventing the cold extrusion sleeve 1 from slipping or separating from the cement, and improving the reliability of the structural connection and the overall stability. The ribs 2 have a specific cross-sectional shape and arrangement. They are integrally formed and seamlessly fixed to the outer peripheral wall of the sleeve outer layer 101, providing a reliable mechanical foundation for the entire cold-extruded sleeve 1. Multiple ribs 2 are evenly spaced along the circumference of the sleeve outer layer 101, and each rib 2 extends axially along the sleeve outer layer 101. Grooves for accommodating and locking cement are naturally formed between the ribs 2. When the cold-extruded sleeve 1 is embedded in the cement matrix, the cement fills these grooves and solidifies. Then it forms a strong mechanical engagement with the rib 2. The cross-sectional shape of the rib 2 can be set as a trapezoid, and the hypotenuse of the trapezoid can form a hook-shaped locking angle to further enhance the engagement effect with the cement and prevent minor slippage when under force. The cross-sectional shape of the rib 2 can also be set as a rectangle, which can also provide sufficient contact surface and engagement force. The arrangement of the rib 2 can also be set as a spiral around the outer peripheral wall of the sleeve outer layer 101, which can resist torsional load to a certain extent and provide multi-dimensional stability for the connection. To facilitate a secure connection between the cold extrusion sleeve 1 and other components such as reinforcing bars, the inner circumferential wall of the inner layer 102 of the sleeve is provided with threads. These threads are internal threads. Through the meshing connection of the threads, the reliability of the transmission of axial force between the cold extrusion sleeve 1 and the connected component can be ensured. To facilitate the smooth insertion of the cold extrusion sleeve 1 into the uncured cement matrix during construction, reduce insertion resistance, and play a guiding role, the axial end of the cold extrusion sleeve 1 is provided with a chamfer. The chamfer is set on the outer circumferential side of the axial end of the cold extrusion sleeve 1 to form a smooth transition surface.

[0019] Working principle: During construction, the cold extrusion sleeve 1 is placed into the uncured cement matrix. The cement slurry will completely wrap the outer layer 101 of the sleeve and fill the space between each rib 2. After the cement solidifies and hardens, the hardened cement and the ribs 2 form a tight and interlocking mechanical interlocking structure. At the same time, the setting of the ribs 2 significantly increases the total contact area between the cold extrusion sleeve 1 and the cement, thereby generating huge friction and adhesion. When the cold extrusion sleeve 1 is subjected to axial load, whether it is tension or pressure, the side of the rib 2 will directly generate a strong normal support force with the hardened cement. This support force effectively prevents the cold extrusion sleeve 1 from sliding or separating axially relative to the cement. The integral molding structure of the outer sleeve 101, the inner sleeve 102, and the rib 2 ensures that the cold extruded sleeve 1 has high structural strength and that the rib 2 will not be sheared or damaged under huge stress. The inner sleeve 102 is connected to the steel bars and other components through internal threads, which stably transfers the load to the entire cold extruded sleeve 1. The load is then transferred to the cement matrix through the gripping force formed by the outer sleeve 101 and the rib 2, thereby achieving a firm connection of the components and improving the reliability of the structural connection and the overall stability.

Claims

1. An axially cold-extruded sleeve with gripping force with cement, comprising: A cold-extruded sleeve (1) and an outer sleeve layer (101) are provided, wherein an inner sleeve layer (102) is coaxially disposed on the outer sleeve layer (101), and the inner sleeve layer (102) is located inside the outer sleeve layer (101); the outer sleeve layer (101), the inner sleeve layer (102), and the protruding rib (2) are integrally formed to constitute the cold-extruded sleeve (1), characterized in that: The rib (2) is integrally formed on the outer peripheral wall of the sleeve outer layer (101). The rib (2) is connected to the outer peripheral wall of the sleeve outer layer (101) without gap. The rib (2) extends along the axial direction of the sleeve outer layer (101), and multiple ribs (2) are evenly spaced along the circumference of the sleeve outer layer (101).

2. The axial cold extrusion sleeve with gripping force with cement according to claim 1, characterized in that: The cross-sectional shape of the rib (2) is trapezoidal.

3. The axial cold extrusion sleeve with gripping force with cement according to claim 1, characterized in that: The cross-sectional shape of the rib (2) is rectangular.

4. The axial cold extrusion sleeve with gripping force with cement according to claim 1, characterized in that: The rib (2) spirals around the outer peripheral wall of the outer layer (101) of the sleeve.

5. An axial cold-extruded sleeve with gripping force with cement as described in claim 1, characterized in that: The inner circumferential wall of the inner layer (102) of the sleeve is provided with threads.

6. The axial cold extrusion sleeve with gripping force with cement according to claim 5, characterized in that: The thread is an internal thread.

7. An axial cold-extruded sleeve with gripping force with cement according to claim 1, characterized in that: The axial end of the cold extrusion sleeve (1) is chamfered.

8. An axial cold-extruded sleeve with gripping force with cement according to claim 7, characterized in that: The chamfer is located on the outer periphery of the axial end of the cold extrusion sleeve (1).

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