Method for separating metal rubber part by utilizing ozone

Abstract

The invention discloses a method for separating metal and rubber parts by utilizing ozone. The method comprises the following steps: S1, rubber aging; S2, metal and rubber part separation; S3, residual rubber cleaning; according to the method provided by the invention, the aging and denaturation of the rubber part are accelerated by utilizing ozone, so that the rubber part loses the original high elasticity and rigidity, the adhesive force with the metal part is reduced, the energy consumption of mechanical separation is subsequently reduced, and excessive damage to the metal part in mechanical separation is avoided; therefore, rubber part separation and metal part recycling can be efficiently and reliably achieved.

Description

Technical Field

[0001] The present invention relates to the field of low-carbon recycling and remanufacturing of metal-rubber vibration damping components in rail transportation, and in particular to a method for separating metal-rubber components by utilizing ozone. Background Art

[0002] In the rail transit sector, locomotive bogies contain numerous metal-rubber composite vibration damping components, providing flexible support for locomotive operation. Common examples include conical springs, ball joints (nodes), and cover plates. These metal-rubber components are typically vulcanized metal and rubber components, leveraging the rubber's high elasticity and strength to provide a certain degree of flexible support and rigidity. These metal-rubber components are consumable and often require complete replacement after extended operation. While aging and failure typically occur in the rubber component, the metal component still has recycling value. Efficiently separating the rubber from the metal-rubber component is crucial for the recycling and remanufacturing of the metal component. Prior art methods exist for mechanically stripping the rubber component to recover the metal component. However, while the rubber component may not retain its original properties, it still possesses considerable elasticity and rigidity. Direct mechanical stripping consumes significant energy and may damage the metal component. Therefore, prior to direct mechanical stripping, pre-treating the rubber component to reduce its mechanical strength and adhesion to the metal component would facilitate subsequent separation and recovery of the metal component.

[0003] A search revealed relevant prior art documents. For example, publication number CN1186461A, entitled "Method for Recycling Industrial Rubber Products," discloses a method for using ozone to separate industrial rubber products into scraps for recycling. It provides technical guidance on using ozone to degrade rubber components, facilitating their separation from metal parts. However, for some metal-rubber composite vibration damping components used in locomotives, this existing solution still requires refinement and improvement to reliably and efficiently separate rubber components and provide a pre-processing solution for recycling metal components. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for separating metal rubber parts using ozone, comprising the following steps: Rubber aging S1: Place the metal rubber parts in a closed space and let them stand. Ozone is then injected into the closed space, causing the rubber parts in the metal rubber parts and the rubber parts connected by vulcanization to age and lose their high elasticity and strength. Metal-rubber part separation S2: using mechanical pressure to press out the rubber part, so that the metal part and the rubber part are separated; Residual glue cleaning S3, cleaning the residual glue attached to the surface of the separated metal parts, so that all the rubber on the surface of the metal parts is removed; Metal parts surface treatment S4, the surface of the metal parts is sandblasted and cleaned to meet the surface roughness requirements of the re-vulcanization production.

[0005] Furthermore, the method further includes a pre-processing step S0 of applying and maintaining prestress to the metal part in the metal rubber part so that the rubber part is in a non-free state, and then performing the rubber aging step S1.

[0006] Furthermore, in the pre-processing step S0, prestress is applied to put the rubber component in a stretched state.

[0007] Furthermore, in the pre-processing step S0, prestress is applied to put the rubber component in a shear state.

[0008] Furthermore, when the metal rubber part is a conical spring, a pre-processing tool is provided, and the prestress is applied by using the tool.

[0009] Furthermore, the conical spring includes an outer sleeve and a core shaft, a conical rubber body is vulcanized and connected between the outer sleeve and the core shaft, a first mounting hole is provided in the center of the core shaft, and a second mounting hole is provided at the bottom of the outer sleeve; the pre-processing tool includes a base, a top column is vertically connected to the base, a first threaded hole is provided on the base, and a pressure ring is provided with a through hole matching the second mounting hole; in the pre-processing step S0, the following steps are specifically included: S01, inverting the conical spring so that the end of the core shaft and the top column are in conflict; S02, place the pressure ring on the outer periphery of the outer sleeve, insert bolt 1 into the through hole in the pressure ring and make bolt 1 pass through mounting hole 2 and enter threaded hole 1, tighten bolt 1 to press the outer sleeve downward, thereby putting the rubber body in a stretched state and maintaining it.

[0010] Furthermore, the pre-processing tooling also has a locking mechanism for locking the conical spring upside down on the top column; in the step S02, after inserting the bolt 1, the pressure ring is rotated, and then the bolt 1 is tightened, so that the rubber body is in a tensile and shear state and maintained.

[0011] Furthermore, the locking mechanism includes a second threaded hole, a pressure plate and a second bolt on the top column. In step S01, after the conical spring is inverted, the pressure plate is covered on the upper end of the core shaft, and the second bolt is passed through the pressure plate and the first mounting hole and screwed into the second threaded hole to lock the conical spring on the top column.

[0012] Alternatively, the locking mechanism includes a stud connected to the top column, and the first mounting hole is a threaded hole. The stud can be used to lock the conical spring on the top column, and the thread rotation direction of the stud is the same as the rotation direction of the pressure ring in step S02.

[0013] Furthermore, in the rubber aging step S1, the enclosed space is heated, the temperature is controlled at 50-100° C., the ozone concentration is controlled at 300-500 ppm, and the metal rubber part is left to stand for more than 24 hours to age.

[0014] Compared with the existing technology, the technical solution of the present application has the following beneficial effects: the method proposed in the present invention uses ozone to accelerate the aging and degeneration of rubber parts, causing them to lose their original high elasticity and rigidity, reducing their adhesion to metal parts, and subsequently reducing the energy consumption of mechanical separation, avoiding excessive damage to metal parts during mechanical separation, thereby enabling efficient and reliable separation of rubber parts and recycling of metal parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 : Schematic diagram of the conical spring in tension and shear state after prestressing in the pre-processing tooling Figure 1 ; Figure 2 : Schematic diagram of the conical spring in shear state after prestressing in the pre-processing fixture; Figure 3 : Schematic diagram of the conical spring in a stretched state after being prestressed in the pre-processing fixture; Figure 4 : Schematic diagram of the conical spring in tension and shear state after prestressing in the pre-processing tooling Figure 2 ; Figure 5 : Schematic diagram of the basic structure of the cone spring. DETAILED DESCRIPTION

[0016] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0017] A method for separating metal rubber parts using ozone comprises the following steps: Rubber aging S1: Place the metal rubber parts in a closed space and let them stand. Ozone is then injected into the closed space, causing the rubber parts in the metal rubber parts and the rubber parts connected by vulcanization to age and lose their high elasticity and strength. Metal-rubber part separation S2: using mechanical pressure to press out the rubber part, so that the metal part and the rubber part are separated; Residual glue cleaning S3, cleaning the residual glue attached to the surface of the separated metal parts, so that all the rubber on the surface of the metal parts is removed; Metal parts surface treatment S4, the surface of the metal parts is sandblasted and cleaned to meet the surface roughness requirements of the re-vulcanization production.

[0018] The above are the basic steps of this method. When the metal rubber parts are in an ozone environment for a period of time, their aging will be accelerated, causing them to lose their original high elasticity and strength, and the adhesion between the metal parts and them will be reduced. After accelerated aging, there is no need to apply too much mechanical load to the metal parts to separate the rubber parts, and obtain metal parts with only residual glue attached to the surface. In this process, because the metal parts are subjected to less mechanical load, their loss, damage and mechanical deformation are less, which provides the possibility for subsequent recycling in manufacturing. The ozone generation and reaction device can adopt the ozone reactor commonly used in the prior art. The residual glue can be cleaned by mechanical methods such as iron brushes. It should be noted that even if the damage to the metal parts during the separation process is small, they still have deformation in size and shape compared to new products. They can be processed later through shaping, compensation and other methods, and the recycled metal parts can be downgraded for use.

[0019] In a more preferred embodiment, the step of pre-treatment S0 is further included, wherein pre-stress is applied to the metal part of the metal rubber part and maintained so that the rubber part is in a non-free state, and then the step of rubber aging S1 is performed.

[0020] While ozone can accelerate the aging of rubber parts, metal-to-rubber parts, especially those like conical springs and ball joints, are largely vulcanized to the metal, leaving little exposed area. Therefore, the area exposed to ozone is limited. To further increase the rubber's exposure to ozone, a certain amount of prestress can be applied to the metal before placing it in the reactor, placing it in a non-free state. As the rubber begins to age and denature, its elasticity and strength decrease. This prestress accelerates the cracking and dispersion of the rubber, further increasing its exposure to ozone. As the reaction time increases, the metal's adhesion to the rubber may fail under this prestress, potentially leading to partial separation of the rubber part within the reactor.

[0021] It should be noted that, under normal circumstances, the rubber body of the metal-rubber vibration damping device used in locomotives is generally in a free state or a pre-compressed state. This rubber part state means that there will not be a large prestress between the metal and rubber parts. Therefore, in order to accelerate the aging separation of the rubber body and increase the reaction contact area, a certain amount of additional prestress needs to be applied.

[0022] In a more preferred embodiment, during the pre-treatment step S0, a prestress is applied to the rubber component to place it in a stretched state. As described in the aforementioned embodiments, in actual products, rubber components are typically in a free or pre-compressed state. While applying prestress can accelerate separation under this prestress, the separation effect is still limited because the separation direction tends toward compression. Rubber components generally have significantly greater mechanical strength against compression than against tension. Therefore, in metal-rubber vibration damping devices, it is important to avoid placing the rubber component in a stretched state as much as possible, as this significantly reduces its service life. In this embodiment, this property is exploited by prestressing the rubber component to place it in a stretched state. During aging, the prestress will cause the rubber component to crack and age in the direction of separation, thereby further increasing its reactive contact area with ozone.

[0023] In a more preferred embodiment, during the pre-treatment step S0, prestress is applied to the rubber component to place it in a shear state. Continuing with the aforementioned embodiment, the shear prestress applied to the rubber component also causes it to separate and fracture during aging, unlike compressive prestress, which tends to cause it to separate and fracture. If the rubber component is subjected to both shear and tensile prestress, it will rapidly age and fracture.

[0024] In a more preferred embodiment, when the metal rubber part is a conical spring 1, a pre-processing tool 2 is provided to apply the prestress. In this embodiment, a common conical spring 1 among metal rubber parts will be used to illustrate how to apply the prestress in the various states mentioned above. The structure of the conical spring 1 can be found in Figure 5 The conical spring 1 includes an outer sleeve 11 and a core shaft 12, with a conical rubber body 13 vulcanized and connected between the outer sleeve 11 and the core shaft 12. The core shaft 12 has a first mounting hole 121 in the center, and a second mounting hole 111 at the bottom of the outer sleeve 11. The first mounting hole 121 is a through hole in some cases, but it can also be a threaded hole.

[0025] like Figure 1 As shown, the thick black solid line depicts the pre-processing tool 2, which includes a base 21, a top column 22 vertically connected to the base 21, a threaded hole 1 211 formed on the base 21, and a pressure ring 23, a through hole 231 matching the mounting hole 2 111 formed on the pressure ring 23, and handles connected to both ends of the pressure ring 23 for easy rotation of the pressure ring 23; in the pre-processing step S0, the following steps are specifically included: S01, see Figure 1 , invert the conical spring 1 so that the end of the core shaft 12 conflicts with the top column 22. The conical spring 1 is inverted so that the conical rubber body can be in a stretched state when the outer sleeve is pressed down.

[0026] S02, see Figure 3, put the pressure ring 23 on the outer periphery of the outer sleeve 11, insert the bolt 24 into the through hole 231 in the pressure ring 23 and let the bolt 24 pass through the mounting hole 2 111 and enter the threaded hole 1 211, tighten the bolt 24 to press the outer sleeve 11 downward, thereby putting the rubber body 13 in a stretched state and maintaining it.

[0027] In a more preferred embodiment, the pre-processing tool 2 further has a locking mechanism for locking the conical spring 1 upside down on the top column 22; in the step S02, after inserting the bolt 24, the pressure ring 23 is rotated, and then the bolt 24 is tightened, so that the rubber body 13 is in a tension and shear state and maintained. For details, please refer to Figure 2 In this embodiment, the downward pressure of the pressure ring 23 puts the rubber body 13 in a tensile state, and the rotation of the pressure ring 23 puts the downward pressure of the pressure ring 23 in a shear state. At this time, the opening direction of the threaded hole 1 211 will present a certain angle with the mounting hole 2 111. After the pressure ring 23 is rotated, the bolt 1 24 will be aligned with the threaded hole 1 211, and the rotation angle of the pressure ring 23 can be maintained by the bolt 1 24. The front end of the bolt 1 24 may not be threaded. After aligning with the threaded hole 1 211, it can be directly inserted to lock the rotation angle of the pressure ring 23. Subsequently, tightening the bolt 1 24 can continue to apply the tensile prestress. The function of the locking mechanism is to prevent the core shaft 12 from being driven to rotate under the shear prestress of the rubber body 13, so that the shear prestress disappears.

[0028] An embodiment of a locking mechanism can be found in Figures 1 to 3 The locking mechanism includes a second threaded hole 221 formed on the top column 22, a pressure plate 25, and a second bolt 26. In step S01, the conical spring 1 is inverted, and the pressure plate 25 is placed on the upper end of the core shaft 12. The second bolt 26 penetrates the pressure plate 25 and the first mounting hole 121 and is screwed into the second threaded hole 221 to lock the conical spring 1 to the top column 22. This embodiment is suitable for situations where the first mounting hole 121 is a through hole.

[0029] When the mounting hole 121 is a threaded hole, the implementation of the locking mechanism will be more concise. Figure 4 The locking mechanism includes a stud 222 connected to the top post 22. Mounting hole 121 is a threaded hole. The stud 222 is used to lock the conical spring 1 to the top post 22. The threaded direction of the stud 222 is the same as the rotation direction of the pressure ring 23 in step S02. Under the shear prestress generated by the rotation of the pressure ring 23, the core shaft 12 will be locked to the top post 22 and will not rotate with it.

[0030] In a more preferred embodiment, in the rubber aging step S1, the enclosed space is heated, the temperature is controlled at 50-100°C, the ozone concentration is controlled at 300-500 ppm, and the metal rubber part is left to stand for more than 24 hours to age.

[0031] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply the existence of any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0032] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for separating metal rubber parts using ozone, characterized in that: The following steps are included: Rubber aging S1: Place the metal rubber parts in a closed space and let them stand. Ozone is then injected into the closed space, causing the rubber parts in the metal rubber parts and the rubber parts connected by vulcanization to age and lose their high elasticity and strength. Metal-rubber part separation S2: using mechanical pressure to press out the rubber part, so that the metal part and the rubber part are separated; Residual glue cleaning S3, cleaning the residual glue attached to the surface of the separated metal parts, so that all the rubber on the surface of the metal parts is removed; Metal parts surface treatment S4, the surface of the metal parts is sandblasted and cleaned to meet the surface roughness requirements of the re-vulcanization production.

2. The method for separating metal rubber parts using ozone according to claim 1, wherein: The method further includes a pre-processing step S0 of applying prestress to the metal part of the metal rubber part and maintaining the prestress so that the rubber part is in a non-free state, and then performing the rubber aging step S1.

3. The method for separating metal rubber parts using ozone according to claim 2, wherein: In the pre-processing step S0, prestress is applied to put the rubber component in a stretched state.

4. The method for separating metal rubber parts using ozone according to claim 3, wherein: In the pre-processing step S0, prestress is applied to put the rubber component in a shear state.

5. The method for separating metal rubber parts using ozone according to claim 4, characterized in that: When the metal rubber part is a conical spring (1), a pre-processing tool (2) is provided, and the prestress is applied by using the tool.

6. The method for separating metal rubber parts using ozone according to claim 5, characterized in that: The conical spring (1) comprises an outer sleeve (11) and a core shaft (12), a conical rubber body (13) is vulcanized and connected between the outer sleeve (11) and the core shaft (12), a first mounting hole (121) is provided at the center of the core shaft (12), and a second mounting hole (111) is provided at the bottom of the outer sleeve (11); the pre-processing tool (2) comprises a base (21), a top column (22) is vertically connected to the base (21), a first threaded hole (211) is provided on the base (21), and a pressure ring (23) is provided on the pressure ring (23), and a through hole (231) matching the second mounting hole (111) is provided; in the pre-processing step S0, the following steps are specifically included: S01, inverting the conical spring (1) so that the end of the core shaft (12) and the top column (22) are in conflict with each other; S02, a pressure ring (23) is placed on the outer periphery of the outer sleeve (11), a bolt (24) is inserted into the through hole (231) in the pressure ring (23), and the bolt (24) is passed through the second mounting hole (111) and enters the threaded hole (211), and the bolt (24) is tightened to press the outer sleeve (11) downward, thereby putting the rubber body (13) in a stretched state and maintaining it.

7. The method for separating metal rubber parts using ozone according to claim 6, characterized in that: The pre-processing tool (2) also has a locking mechanism for locking the conical spring (1) upside down on the top column (22); in the step S02, after the bolt (24) is inserted, the pressure ring (23) is rotated, and the bolt (24) is tightened, so that the rubber body (13) is in a tensile and shear state and maintained.

8. The method for separating metal rubber parts using ozone according to claim 7, wherein: The locking mechanism includes a second threaded hole (221) on the top column (22), a pressure plate (25) and a second bolt (26). In the step S01, after the conical spring (1) is inverted, the pressure plate (25) is covered on the upper end of the core shaft (12), and the second bolt (26) is passed through the pressure plate (25) and the first mounting hole (121) and screwed into the second threaded hole (221) to lock the conical spring (1) on the top column (22).

9. The method for separating metal rubber parts using ozone according to claim 7, wherein: The locking mechanism includes a stud (222) connected to the top column (22), and the mounting hole (121) is a threaded hole. The stud (222) can be used to lock the conical spring (1) on the top column (22), and the thread rotation direction of the stud (222) is the same as the rotation direction of the pressure ring (23) in step S02.

10. The method for separating metal rubber parts using ozone according to any one of claims 1 to 9, characterized in that: In the rubber aging step S1, the enclosed space is heated, the temperature is controlled at 50-100° C., the ozone concentration is controlled at 300-500 ppm, and the metal rubber part is left to stand for more than 24 hours to age.

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