A polyurethane wheel

Abstract

The utility model discloses a kind of polyurethane wheels, it is related to polyurethane wheel technical field, including wheel core, modulus gradient transition layer and polyurethane layer, modulus gradient transition layer is poured in the outer edge of wheel core, polyurethane layer is poured in the outer edge of modulus gradient transition layer, the elastic modulus of modulus gradient transition layer is between the elastic modulus of polyurethane layer and steel pipe material elastic modulus. Entire polyurethane wheel is light in weight, can integrally pour polyurethane, so the overall strength of polyurethane layer is higher than the strength of the polyurethane layer of wheel group. When wheel piece is in load state, the pressure that polyurethane layer bears is transferred to modulus gradient transition layer, then by modulus gradient transition layer is transferred to wheel core. Since the elastic modulus of modulus gradient transition layer material is between polyurethane and steel pipe, stress buffering effect is played, so the stress between polyurethane layer and modulus gradient transition layer is less than the stress between the polyurethane layer of conventional structure wheel piece and metal wheel core.

Description

Technical Field

[0001] This utility model relates to the field of polyurethane wheel technology, and in particular to a polyurethane wheel. Background Technology

[0002] Polyurethane wheels are typically made by casting polyurethane onto the surface of a metal wheel core. The polyurethane wheels on tunnel boring machines (TBMs) often bear loads of tens of tons. The diameter of a polyurethane wheel is generally between 300-500 mm, and the axial width can exceed 600 mm. Therefore, manufacturing a single polyurethane wheel is extremely heavy, and the polyurethane casting process is very difficult. Consequently, polyurethane wheels on TBMs are usually manufactured in wheel assemblies: multiple wheel pieces are press-fitted with a cylindrical steel mandrel using an interference fit. The wheel pieces are made by casting polyurethane material onto the surface of a steel rim. Multiple wheel pieces arranged side-by-side form a polyurethane wheel assembly, dividing the polyurethane layer into multiple segments, reducing the overall strength of the polyurethane layer of the assembly. The wheel axis has a certain angle with the ground. Under the gravity of the TBM, the polyurethane layer of the wheel assemblies often fails to adhere to the steel rim during use, causing it to peel off from the rim surface. When the polyurethane layer of the wheel piece peels off, the entire polyurethane wheel assembly needs to be replaced, leading to project shutdown. Utility Model Content

[0003] The purpose of this invention is to provide a polyurethane wheel to solve the above-mentioned technical problems.

[0004] The technical solution adopted in this utility model is as follows: A polyurethane wheel includes a wheel core, a modulus gradient transition layer, and a polyurethane layer. The modulus gradient transition layer is cast onto the outer edge of the wheel core, and the polyurethane layer is cast onto the outer edge of the modulus gradient transition layer. The elastic modulus of the modulus gradient transition layer is between the elastic modulus of the polyurethane layer and the elastic modulus of the wheel core material.

[0005] Preferably, the outer edge of the wheel core is provided with several bosses.

[0006] As a further preferred embodiment, a plurality of the bosses are distributed along the circumferential direction of the wheel core.

[0007] As a further preferred embodiment, several of the bosses are distributed along the axial direction of the wheel core.

[0008] Preferably, the thickness of the modulus gradient transition layer is greater than the thickness of the wheel core and the thickness of the polyurethane layer.

[0009] Preferably, the outer peripheral wall of the modulus gradient transition layer is treated with sandblasting and adhesive coating.

[0010] Preferably, the outer contour of the polyurethane layer is arc-shaped.

[0011] Preferably, the modulus gradient transition layer is an MC nylon layer cast onto the outer edge of the wheel core.

[0012] Preferably, the polyurethane layer is a polyurethane material layer cast onto the outer edge of the modulus gradient transition layer.

[0013] The above technical solution has the following advantages or beneficial effects: In this invention, the entire polyurethane wheel is lightweight and can be integrally cast with polyurethane, resulting in a higher overall strength of the polyurethane layer compared to the wheel assembly. When the wheel is under load, the pressure on the polyurethane layer is transferred to the modulus gradient transition layer, and then from the transition layer to the wheel core. Because the elastic modulus of the modulus gradient transition layer material is between that of the polyurethane and the wheel core, it acts as a stress buffer, thus reducing the stress between the polyurethane layer and the transition layer compared to the stress between the polyurethane layer and the metal wheel core in conventional wheel structures. The increased overall strength of the polyurethane layer and the significantly reduced stress at the bonding surface between the polyurethane layer and the wheel core significantly extend the lifespan of the polyurethane wheel, greatly reducing polyurethane layer detachment failure during tunneling. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the polyurethane wheel in this utility model; Figure 2 This is a perspective view of the wheel core in this utility model.

[0015] In the diagram: 1. Wheel core; 101. Boss; 2. Modulus gradient transition layer; 3. Polyurethane layer; 4. Tunnel concrete segment. Detailed Implementation

[0016] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0017] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0018] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0019] Please see Figure 1 The diagram illustrates a preferred embodiment of a polyurethane wheel, comprising a wheel core 1, a modulus gradient transition layer 2, and a polyurethane layer 3. The modulus gradient transition layer 2 is cast onto the outer edge of the wheel core 1, and the polyurethane layer 3 is cast onto the outer edge of the modulus gradient transition layer 2. The elastic modulus of the modulus gradient transition layer 2 is between that of the polyurethane layer 3 and the wheel core material, serving as a stress transition and buffer, effectively alleviating stress concentration caused by the large difference in elastic modulus between the polyurethane layer 3 and the wheel core 1. In this embodiment, the wheel core 1 is used as a supporting component. An MC nylon layer is cast onto the outer edge (outer surface) of the wheel core 1 to form the modulus gradient transition layer 2, and then a polyurethane material layer is cast onto the outer edge (outer surface) of the modulus gradient transition layer 2 to form the polyurethane layer 3. The polyurethane layer 3 is used to match the curvature of the tunnel concrete segment 4.

[0020] In this embodiment, the modulus gradient transition layer 2 improves the stress distribution between the polyurethane layer 3 and the wheel core 1, enhances the bonding force between them, and effectively reduces the phenomenon of polyurethane layer 3 peeling off from the surface of wheel core 1. This improves the reliability and service life of the polyurethane wheel, reduces the number of project downtimes caused by polyurethane wheel failures, and improves engineering efficiency. Furthermore, it avoids the problem of reduced overall strength of polyurethane layer 3 caused by assembling multiple polyurethane wheels into a wheel assembly, thus improving the overall performance of the wheel.

[0021] Furthermore, as a preferred embodiment, the outer edge of the wheel core 1 is provided with a plurality of protrusions 101. This prevents displacement between the modulus gradient transition layer 2 and the wheel core 1. When the protrusions 101 are distributed along the circumferential direction, the contact area between the wheel core 1 and the modulus gradient transition layer 2 is increased, allowing the modulus gradient transition layer 2 to better wrap the protrusions 101 during casting, thereby enhancing the mechanical connection strength between the two. When the protrusions 101 are distributed along the axial direction, they also increase the contact area and help disperse stress during wheel rotation, preventing the modulus gradient transition layer 2 from separating from the wheel core 1 due to excessive local stress. This arrangement improves the robustness of the connection between the wheel core 1 and the modulus gradient transition layer 2. By increasing the contact area and dispersing stress, the connection stability between the wheel core 1 and the modulus gradient transition layer 2 is improved, further enhancing the reliability of the overall wheel structure.

[0022] Furthermore, as a preferred embodiment, the thickness of the modulus gradient transition layer 2 is greater than the thickness of the wheel core 1 and the polyurethane layer 3. In this embodiment, the thicker modulus gradient transition layer 2 can provide more sufficient stress buffer space and better exert its stress transition function. It can more effectively absorb and disperse the stress transmitted to the polyurethane layer 3 and the wheel core 1 during the operation of the tunnel boring machine, avoiding stress concentration from damaging the bonding surface between the polyurethane layer 3 and the modulus gradient transition layer 2 and the wheel core 1.

[0023] Furthermore, as a preferred embodiment, the outer peripheral wall of the modulus gradient transition layer 2 is treated with sandblasting and adhesive application. After sandblasting and adhesive application, the polyurethane layer 3 is then cast onto the outer peripheral wall of the modulus gradient transition layer 2. Sandblasting roughens the surface of the modulus gradient transition layer 2, increasing the surface area and thus improving the mechanical bonding ability with the polyurethane layer 3. Adhesive application further enhances the chemical adhesion between the two, making the bond between the polyurethane layer 3 and the modulus gradient transition layer 2 even tighter.

[0024] Furthermore, as a preferred embodiment, the outer contour of the polyurethane layer 3 is arc-shaped to adapt to the curvature of the tunnel concrete segment 4.

[0025] When the tunnel boring machine (TBM) is working, its weight is transferred to the modulus gradient transition layer 2 via the wheel core 1, and then the modulus gradient transition layer 2 transfers the pressure to the polyurethane layer 3. The elastic modulus of polyurethane material is in the tens of MPa range, while that of MC nylon is around 2000 MPa, and the elastic modulus of the wheel core is greater than 200 GPa. Therefore, compared with the conventional polyurethane wheel structure where the polyurethane layer 3 is directly cast onto the metal surface, the stress at the bonding surface between the polyurethane layer 3 and the modulus gradient transition layer 2 in this embodiment is significantly reduced (the stress decreases by more than 30% when the radial load on a single polyurethane wheel is 32 tons). Furthermore, due to the increased overall strength of the polyurethane layer 3, the lifespan of the polyurethane wheel is greatly extended.

[0026] The above description is only a preferred embodiment of the present utility model and does not limit the implementation method and protection scope of the present utility model. Those skilled in the art should realize that all solutions obtained by equivalent substitutions and obvious changes made based on the description and illustrations of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A polyurethane wheel, characterized in that, It includes a wheel core, a modulus gradient transition layer, and a polyurethane layer. The modulus gradient transition layer is cast on the outer edge of the wheel core, and the polyurethane layer is cast on the outer edge of the modulus gradient transition layer. The elastic modulus of the modulus gradient transition layer is between the elastic modulus of the polyurethane layer and the elastic modulus of the steel pipe material.

2. The polyurethane wheel as described in claim 1, characterized in that, The outer edge of the wheel core is provided with several protrusions.

3. The polyurethane wheel as described in claim 2, characterized in that, Several of the aforementioned bosses are distributed along the circumferential direction of the wheel core.

4. The polyurethane wheel as described in claim 2, characterized in that, Several of the aforementioned bosses are distributed along the axial direction of the wheel core.

5. The polyurethane wheel as described in claim 1, characterized in that, The thickness of the modulus gradient transition layer is greater than the thickness of the wheel core and the thickness of the polyurethane layer.

6. The polyurethane wheel as described in claim 1, characterized in that, The outer peripheral wall of the modulus gradient transition layer is treated with sandblasting and adhesive coating.

7. The polyurethane wheel as described in claim 1, characterized in that, The outer contour of the polyurethane layer is arc-shaped.

8. The polyurethane wheel as described in claim 1, characterized in that, The modulus gradient transition layer is an MC nylon layer cast onto the outer edge of the wheel core.

9. The polyurethane wheel as described in claim 1, characterized in that, The polyurethane layer is a polyurethane material layer cast onto the outer edge of the modulus gradient transition layer.

Images