Valve box liner structure for a pump

Abstract

The utility model discloses a kind of valve box bushing structures for pump, comprising: inner bushing, set in the sealing cavity of valve box, its outer surface cooperates with valve box sealing surface;Retainer ring, for the axial fixation of the inner bushing in the sealing cavity of the valve box;Sealing ring, set between the inner bushing and valve box, for realizing the sealing between both;Wherein, the sealing cavity of the valve box is equipped with limit structure, the retainer ring cooperates with the limit structure, and the inner bushing is axially limited together by it.The utility model solves the early failure problem of valve box caused by the easy wear of valve box sealing surface.

Description

Technical Field

[0001] This utility model relates to the field of cementing and fracturing pump technology. More specifically, this utility model relates to a valve box inner liner structure for a pump. Background Technology

[0002] In the oil extraction industry, cementing and fracturing pumps are key equipment for enhancing oil and gas production. During operation, the valve box, its core component, endures prolonged high-pressure, high-frequency fluid erosion and friction from the seals, operating under extremely harsh conditions. In existing valve box structures, the sealing surfaces directly contact packing and other seals, making them highly susceptible to wear after extended operation. If the wear exceeds permissible limits, it can lead to seal failure and high-pressure fluid leakage. This can result in anything from costly and complex maintenance requiring shutdown to serious damage to the valve box itself, rendering it unusable. This not only increases the intensity of oilfield operations but also incurs significant economic costs.

[0003] Currently, there are some technical solutions that use interference fit to press in wear-resistant bushings in an attempt to improve wear resistance. However, such structures are extremely difficult to disassemble after the bushings wear out, and it is often impossible to replace the bushings individually, resulting in high maintenance costs and inconvenience. Summary of the Invention

[0004] The purpose of this invention is to provide a valve box inner bushing structure for pumps, which solves the problem of early valve box failure caused by easy wear of the valve box sealing surface.

[0005] Another objective of this invention is to provide an inner liner structure that is easy to disassemble and replace. When the inner liner is worn, it can be quickly replaced, thereby significantly reducing maintenance costs and time and extending the service life of the valve box body.

[0006] This invention also aims to ensure the stability and sealing effectiveness of the inner liner under high-pressure conditions through a simple and reliable mechanical fixing and sealing method.

[0007] The technical solution adopted by this utility model to solve this technical problem is: a valve box inner bushing structure for pumps, comprising: The inner liner is installed inside the sealing cavity of the valve box, and its outer surface mates with the sealing surface of the valve box. A retaining ring is used to axially fix the inner bushing into the sealing cavity of the valve box; A sealing ring is disposed between the inner bushing and the valve box to achieve a seal between the two. The valve box has a limiting structure inside its sealing cavity, and the retaining ring cooperates with the limiting structure to axially limit the inner bushing.

[0008] As a further embodiment of this utility model, the limiting structure includes a groove formed on the wall surface of the valve box sealing cavity, and the retaining ring is an elastic retaining ring installed in the groove.

[0009] As a further embodiment of this utility model, the inner liner has a first end face and a second end face; The second end face of the inner liner is in contact with the stepped end face of the valve box sealing cavity; The retaining ring contacts the first end face of the inner bushing, and the inner bushing is fixed bidirectionally in the axial direction through the stepped end face and the retaining ring.

[0010] As a further embodiment of this utility model, the sealing ring is disposed in the sealing groove on the sealing cavity wall of the valve box, and the sealing between the outer surface of the inner bushing and the sealing surface of the valve box is achieved by extrusion deformation.

[0011] As a further embodiment of this invention, the sealing ring is a hydrogenated nitrile rubber sealing ring.

[0012] As a further aspect of this invention, the inner surface of the inner bushing is designed to directly contact the packing seal of the pump.

[0013] As a further embodiment of this utility model, the inner liner is a wear-resistant alloy inner liner or a ceramic inner liner.

[0014] This utility model has at least the following beneficial effects: The pump valve box inner liner structure provided by this utility model creatively achieves convenient installation and replacement of the inner liner by setting a stepped surface at one end for axial positioning and using a detachable retaining ring for fixation at the other end. This design transfers the wear of the valve box sealing surface to the specially designed inner liner, effectively protecting the more expensive valve box body and fundamentally solving the problem of valve box scrapping due to sealing surface wear.

[0015] Because of the use of a retaining ring for fixing, when the inner bushing needs to be replaced, the operator only needs to remove the retaining ring to take out the old bushing and replace it with a new one. The whole process is simple and quick, avoiding the risks of difficult disassembly of traditional interference fit bushings and even damage to the valve box body, which greatly reduces the intensity and time cost of maintenance work.

[0016] The sealing ring in this structure is placed within the sealing groove of the valve box, achieving a seal through reliable extrusion deformation. This effectively prevents high-pressure liquid from leaking between the mating surfaces of the bushing and the valve box, ensuring the sealing reliability of the entire system under high pressure. Simultaneously, the inner bushing is made of highly wear-resistant material, resulting in a long service life and further enhancing the equipment's continuous operation capability. In summary, this utility model has an ingenious structure, strong practicality, and significantly improves the economy and ease of maintenance of the fracturing pump valve box.

[0017] Other advantages, objectives and features of this invention will be partly apparent from the following description, and partly understood by those skilled in the art through study and practice of this invention. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the inner bushing structure of the valve box for the pump of this utility model.

[0019] Among them, 1 is valve box; 11 is valve box sealing surface; 12 is stepped end face; 13 is groove; 14 is sealing groove; 2 is inner bushing; 21 is inner surface of inner bushing; 22 is outer surface of inner bushing; 23 is first end face; 24 is second end face; 3 is retaining ring; 4 is packing seal; 5 is sealing ring. Detailed Implementation

[0020] The present invention will now be described in detail and completely with reference to the accompanying drawings. Those skilled in the art will be able to implement the present invention based on these descriptions. Before describing the present invention with reference to the accompanying drawings, it should be particularly noted that the technical solutions and features provided in the various parts of the present invention, including the following description, can be combined with each other without conflict.

[0021] Furthermore, the embodiments of the present invention described below are generally only a part of the embodiments of the present invention, and not all of the embodiments. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the protection scope of the present invention.

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments, and the specific implementation process is as follows: like Figure 1As shown, this utility model provides a valve box inner bushing structure for pumps, including: an inner bushing 2, disposed within the sealing cavity of the valve box 1, with its outer surface fitting and transitionally fitting the valve box sealing surface 11; a retaining ring 3, used to axially fix the inner bushing within the sealing cavity of the valve box; the retaining ring 3 is required to withstand large shear forces and loads and be easy to disassemble; and a sealing ring 5, disposed between the inner bushing and the valve box, used to achieve a seal between the two; wherein, a limiting structure is provided within the sealing cavity of the valve box, and the retaining ring 3 cooperates with the limiting structure to axially limit the inner bushing. The technical problem solved by this embodiment is that the valve box sealing surface 11 is prone to wear under high-pressure conditions, leading to premature valve box failure, and that the use of interference fit for bushing fixation in the prior art results in inconvenient disassembly and high maintenance costs. This technical solution includes an inner bushing, a retaining ring 3, and a sealing ring 5. The inner bushing is disposed within the valve box sealing cavity, and its outer surface mates with the valve box sealing surface 11. The retaining ring 3 is used to axially fix the inner bushing, and the sealing ring 5 provides a seal. Axial positioning is achieved through the cooperation of the retaining ring 3 with a limiting structure on the valve box. This technical solution eliminates the need for a gland structure and uses the retaining ring 3 for fixing, making the installation and removal of the inner bushing much simpler. When the inner bushing wears out, only the retaining ring 3 needs to be removed to replace the inner bushing, without replacing the entire valve box, significantly reducing maintenance costs and time. At the same time, this structure avoids the disassembly difficulties caused by interference fits, improving maintenance efficiency.

[0023] In another technical solution, the limiting structure includes a groove 13 formed on the wall surface of the valve box sealing cavity, and the retaining ring 3 is an elastic retaining ring 3, which is installed in the groove 13. This technical solution further defines the limiting structure as a groove 13 on the wall surface of the valve box sealing cavity, and the retaining ring 3 as an elastic retaining ring 3. The technical problem solved by this solution is how to achieve quick, reliable fixing and easy disassembly of the inner bushing. In the prior art, the bushing is usually tightened by an interference fit or a gland, requiring special tools or forceful disassembly during disassembly, which can easily damage the valve box. This technical solution uses an elastic retaining ring 3 in conjunction with the groove 13. The elastic retaining ring 3 itself has elastic deformation capability, allowing it to be directly inserted into the groove 13 during installation and easily pried out with a simple tool during disassembly, achieving easy installation and replacement of the inner bushing and improving maintenance convenience.

[0024] In another technical solution, the inner bushing has a first end face 23 and a second end face 24; the second end face 24 of the inner bushing contacts and fits with the stepped end face 12 of the valve box sealing cavity; the retaining ring 3 contacts the first end face 23 of the inner bushing, and the inner bushing is bidirectionally fixed in the axial direction through the stepped end face 12 and the retaining ring 3. This technical solution defines the inner bushing as having a first end face 23 and a second end face 24, with the second end face 24 contacting the stepped end face 12 of the valve box sealing cavity, and the retaining ring 3 contacting the first end face 23, thus achieving bidirectional fixation. The technical problem solved by this technical solution is that the inner bushing may move axially under the action of high-pressure fluid, leading to sealing failure or structural instability. In the prior art, the bushing is fixed only by interference fit or a single-sided gland, which is prone to loosening under alternating loads. This utility model, through the bidirectional limiting of the stepped end face 12 and the retaining ring 3, firmly fixes the inner bushing in the valve box sealing cavity, ensuring its axial stability under high-pressure conditions, thereby improving sealing reliability and equipment service life.

[0025] In another technical solution, the sealing ring 5 is disposed within the sealing groove 14 on the wall surface of the valve box sealing cavity, and the seal between the outer surface 22 of the inner bushing and the sealing surface 11 of the valve box is achieved through extrusion deformation. This design ensures that the sealing ring 5 is disposed within the sealing groove 14 on the wall surface of the valve box sealing cavity, and the seal is achieved through extrusion deformation. The technical problem solved by this solution is that liquid leakage easily occurs between the inner bushing and the valve box mating surface under high pressure. In the prior art, the sealing ring 5 may be disposed on the bushing or gland, and the sealing effect is greatly affected by the installation method. This invention places the sealing ring 5 directly within the sealing groove 14 of the valve box, and through extrusion deformation, it tightly adheres to the outer surface 22 of the inner bushing, forming a reliable static seal, effectively preventing high-pressure fluid leakage and improving the overall sealing performance.

[0026] In another technical solution, the sealing ring 5 is a hydrogenated nitrile butadiene rubber sealing ring 5. Hydrogenated nitrile butadiene rubber has excellent oil resistance, high pressure resistance and corrosion resistance. After adopting this material, the sealing ring 5 can maintain its elasticity and sealing ability during long-term use, extending the sealing cycle and reducing the replacement frequency.

[0027] In another technical solution, the inner surface 21 of the inner bushing is used to directly contact the pump's packing seal 4, wherein the packing is a high-pressure liquid seal. In the prior art, the packing is in direct contact with the valve box, and the valve box needs to be repaired or replaced after wear. This technical solution transfers wear to the inner bushing by having the inner surface 21 of the inner bushing contact the packing. The inner bushing, as a vulnerable part, can be replaced separately, protecting the valve box body and reducing overall maintenance costs.

[0028] In another technical solution, the inner liner is a wear-resistant alloy inner liner or a ceramic inner liner. This technical solution uses wear-resistant alloy or ceramic materials, which have high hardness, high wear resistance and corrosion resistance, significantly improving the service life of the inner liner, reducing downtime and improving equipment operating efficiency.

[0029] Although the embodiments of this utility model have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this utility model. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, this utility model is not limited to the specific details and embodiments shown and described herein.

Claims

1. A valve box inner bushing structure for a pump, characterized in that, include: The inner liner is installed inside the sealing cavity of the valve box, and its outer surface mates with the sealing surface of the valve box. A retaining ring is used to axially fix the inner bushing into the sealing cavity of the valve box; A sealing ring is disposed between the inner bushing and the valve box to achieve a seal between the two. The valve box has a limiting structure inside its sealing cavity, and the retaining ring cooperates with the limiting structure to axially limit the inner bushing.

2. The pump valve box inner bushing structure as described in claim 1, characterized in that, The limiting structure includes a groove formed on the wall of the valve box sealing cavity, and the retaining ring is an elastic retaining ring installed in the groove.

3. The pump valve box inner bushing structure as described in claim 2, characterized in that, The inner liner has a first end face and a second end face; The second end face of the inner liner is in contact with the stepped end face of the valve box sealing cavity; The retaining ring contacts the first end face of the inner bushing, and the inner bushing is fixed bidirectionally in the axial direction through the stepped end face and the retaining ring.

4. The pump valve box inner bushing structure as described in claim 1, characterized in that, The sealing ring is disposed in the sealing groove on the sealing cavity wall of the valve box, and the sealing between the outer surface of the inner bushing and the sealing surface of the valve box is achieved by extrusion deformation.

5. The pump valve box inner bushing structure as described in claim 4, characterized in that, The sealing ring is a hydrogenated nitrile butadiene rubber sealing ring.

6. The pump valve box inner bushing structure as described in claim 1, characterized in that, The inner surface of the liner is designed for direct contact with the pump's packing seal.

7. The pump valve box inner bushing structure as described in claim 1, characterized in that, The inner liner is a wear-resistant alloy inner liner or a ceramic inner liner.

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