A one-way valve device for a positive displacement reciprocating pump

Abstract

The application provides a one-way valve device of a positive displacement reciprocating pump, relates to a one-way valve, and aims to solve the technical problems of low reliability of the one-way valve of the existing positive displacement reciprocating pump, and complex dismounting and low operability when the one-way valve is maintained or replaced. Two one-way valves are used in series in the same way in a single cavity, the mounting mode adopts direct fixing through studs, the end is sealed with a sealing ring, and the two one-way valves work simultaneously; when one of them stops working due to some reasons, the other can still ensure normal work. The failure causes shutdown and production stop; the quick replacement assembly is matched at the connection between the one-way valve and the flange, the complex problems in the maintenance process of the one-way valve are effectively solved, the problems of low reliability and difficult operation in the maintenance of the existing one-way valve of the positive displacement reciprocating pump are solved, manpower and material resources are saved, and the cost performance is high. The operation is convenient, the working efficiency is effectively improved.

Description

Technical Field

[0001] This invention relates to a one-way valve, and more specifically to a one-way valve device for a positive displacement reciprocating pump. Background Technology

[0002] Positive displacement reciprocating pumps can be used in chemical processes. The check valve in a reciprocating pump allows liquid to flow in one direction only, preventing reverse flow. Traditional check valves, such as... Figure 1 As shown, these valves are typically used alone and occupy a large space. When valves malfunction, such as damaged seals or jamming, internal leaks and valve cone breakage can occur in reciprocating pumps, leading to abnormal system flow, pressure, and other parameters, as well as system fluctuations. In severe cases, this can cause system shutdown, resulting in low reliability. Positive displacement reciprocating pumps using check valves operate at high frequency and under high intensity, requiring high reliability and allowing sufficient downtime to ensure a smooth transition between different equipment stages. Furthermore, the valve core, seat, and seals of check valves, which are in direct contact with the transported medium, are vulnerable parts and require frequent replacement. Check valves are tightly connected to flanges and typically use sealing rings at the connection, making disassembly and assembly difficult. Traditional methods involve applying force to move the check valve, resulting in high manpower requirements and workload. Therefore, there is an urgent need to improve valve structure to reduce maintenance costs, save on repair expenses, reduce labor intensity, decrease manpower, and improve replacement efficiency. Summary of the Invention

[0003] The purpose of this invention is to solve the technical problems of low reliability of the check valve in existing positive displacement reciprocating pumps, and the complex disassembly and assembly and low operability of the check valve when maintaining or replacing parts. The invention proposes a check valve device for positive displacement reciprocating pumps.

[0004] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows: A one-way valve device for a positive displacement reciprocating pump is characterized by including an inlet flange, an outlet flange, and a one-way valve assembly and a quick-change assembly installed between the inlet flange and the outlet flange. The one-way valve assembly includes at least one shaft and a primary one-way valve and a secondary one-way valve connected in series. Both the primary and secondary one-way valves have connecting rings on their outer sides. The shaft is fixed between the inlet flange and the outlet flange, and one shaft passes through the connecting rings simultaneously, connecting the primary and secondary one-way valves in series. The inlet and outlet flanges have through holes at their centers, which are respectively connected to the inlet of the primary one-way valve and the outlet of the secondary one-way valve, and the two are connected by a fastening screw pair. The quick-change assembly is located between the one-way valve assembly and the outlet flange, and includes an adjusting bolt, a return spring, and an upper and lower support that interlock. Both the upper and lower supports have through holes at their centers. The lower support has a raised connecting ring near its outer circumference and a recessed placement groove near its inner circumference. The upper support has a placement groove that matches the connecting ring of the lower support, and a connecting ring that matches the placement groove of the lower support. A spring groove is formed inside the upper support, and a threaded hole coaxial with the spring groove is formed inside the lower support. The adjusting bolt passes through the spring groove, and its tail end is fixed in the threaded hole. The return spring is sleeved on the adjusting bolt and located in the spring groove. A high-pressure quick connector communicating with the gap between the lower and upper supports is provided on the outer side of the lower support. The upper support is fixedly connected to the outlet flange by positioning bolts; a support bolt is also installed inside the upper support, and the tail end of the support bolt abuts against the lower support to maintain a gap between the upper support and the lower support.

[0005] Furthermore, a connecting hole is provided between the spring groove and the screw hole, which is opened in the upper support, and the diameter of the spring groove is larger than the diameter of the connecting hole; The spring groove is open at one end facing the upper support, and a round cap is provided at the opening for sealing; the screw hole is closed at one end facing the lower support.

[0006] Furthermore, the adjusting bolt has a stepped structure, with the diameter of the upper half being larger than that of the lower half; the upper half of the adjusting bolt is a smooth-surfaced cylinder with a diameter that matches the connecting hole; the lower half is provided with threads that match the screw hole.

[0007] Furthermore, the tail end of the positioning bolt abuts against the lower support, and the centers of the positioning bolt, the support bolt, and the adjusting bolt are all located on the same circumference, which is distributed on the placement groove of the upper support.

[0008] Furthermore, two shaft grooves and multiple symmetrical screw grooves are provided on the outer side of the inlet flange, and the multiple screw grooves are symmetrically distributed about the diameter connected by the two shaft grooves; The depth of the screw groove toward the center of the inlet flange is greater than the depth of the shaft groove toward the center of the inlet flange; the outlet flange has the same structure.

[0009] Furthermore, the connecting rings of the first-stage check valve extend radially outward, and there are two of them, located at the upper and lower ends of the first-stage check valve respectively. The second-stage check valve has the same structure as the first-stage check valve. The primary check valve is located near the inlet flange, and the secondary check valve is located near the outlet flange.

[0010] Furthermore, sealing rings are provided between the primary check valve and the inlet flange, between the secondary check valve and the quick-change assembly, and between the quick-change assembly and the outlet flange.

[0011] Furthermore, a guide ring assembly, an inner ring sealing assembly, and a high-pressure sealing assembly are provided between the upper support and the lower support. The guide ring assembly is fitted in the middle of the inner ring formed by the placement groove of the lower support; the inner ring sealing assembly is fitted at the end of the inner ring near the upper support; and the high-pressure sealing assembly is fitted at the position of the inner ring near the bottom of the placement groove.

[0012] Furthermore, an outer protective sleeve is fitted at the connection between the outer sides of the upper support and the lower support.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention connects two check valves in series in a single cavity using the same method. The valves are directly fixed with studs and sealed at the ends with sealing rings. The primary and secondary check valves operate simultaneously; if one stops working, the other continues to operate normally. This reduces downtime caused by malfunctions. A quick-change assembly is provided at the connection between the check valve and the flange, effectively solving the complexities of check valve maintenance. It also addresses the low reliability and difficult maintenance issues of existing check valves for positive displacement reciprocating pumps, saving manpower and resources and offering high cost-effectiveness. Furthermore, it is easy to operate and effectively improves work efficiency.

[0014] 2. The quick-change assembly of the present invention is formed by the upper and lower supports engaging. The upper half of the adjusting bolt passes through a return spring and is located in the spring groove of the upper support; the lower half of the adjusting bolt is threaded into the lower support. When the return spring is compressed or reset, the lower support moves relative to the upper support via the lower half of the adjusting bolt. When the check valve assembly is disassembled to replace the valve core, the quick-change assembly's clearance fit allows for convenient disassembly and assembly of the check valve assembly.

[0015] 3. The one-way valve assembly of the present invention is provided with sealing rings at the connection between the inlet flange and the quick-change assembly to ensure the normal operation of the one-way valve assembly; the connection between the lower support and the upper support of the quick-change assembly is provided with an inner ring sealing group and a high-pressure sealing group to allow pressurized oil to be applied smoothly. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a traditional one-way valve in the background art; Figure 2 This is a schematic diagram of a one-way valve device embodiment of a positive displacement reciprocating pump according to the present invention; Figure 3 This is a top view of the inlet flange in an embodiment of a one-way valve device for a positive displacement reciprocating pump according to the present invention; Figure 4 This is a cross-sectional view of the inlet flange in an embodiment of a one-way valve device for a positive displacement reciprocating pump according to the present invention. Figure 5 This is a schematic diagram of the quick-change assembly in an embodiment of a positive displacement reciprocating pump according to the present invention. Figure 6 for Figure 5 A-direction view.

[0017] Explanation of reference numerals in the attached figures: 1-Inlet flange; 2-Sealing ring; 3-Primary check valve; 4-Secondary check valve; 5-Fastening screw assembly; 51-Screw groove; 6-Shaft; 61-Shaft groove; 7-Quick change assembly; 8-Outlet flange; 9-Lower support; 10-Upper support; 11-Outer protective sleeve; 12-Return spring; 13-Positioning bolt; 14-Inner ring sealing assembly; 15-Guide ring assembly; 16-High pressure sealing assembly; 17-High pressure quick connector; 18-Adjusting bolt; 19-Support bolt; 20-Spring groove. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] To address the shortcomings of low reliability and poor operability of existing check valves used in positive displacement reciprocating pumps, and to achieve a higher cost-performance ratio, this invention proposes a check valve device for positive displacement reciprocating pumps, such as... Figure 2 As shown, the one-way valve device includes a one-way valve assembly and a quick-change assembly 7. The one-way valve assembly includes an inlet flange 1 and an outlet flange 8, which are connected by a fastening screw pair 5. A primary one-way valve 3 and a secondary one-way valve 4 are installed in the cavity between the inlet flange 1 and the outlet flange 8. Figure 3 , Figure 4As shown, the inlet flange 1 and outlet flange 8 are provided with four centrally symmetrical screw grooves 51 and two centrally symmetrical shaft grooves 61 around their peripheries. The screw grooves 51 are symmetrically distributed about the diameters connected to the shaft grooves 61. There are four fastening screw pairs 5, with their two ends fixedly connected to the corresponding screw grooves 51 on the inlet flange 1 and outlet flange 8. The depth of the screw grooves 51 towards the flange center is greater than the depth of the shaft grooves 61 towards the flange center. Therefore, after installation, the fastening screw pairs 5 are closer to the primary check valve 3 and the secondary check valve 4 than the shafts 6. The primary check valve 3 is located at the end where the inlet flange 1 is located, and the secondary check valve 4 is located at the end where the outlet flange 8 is located. The primary check valve 3 has two radially outwardly extending connecting rings on its side, with the central axes of the two connecting rings on the same straight line. The secondary check valve 4 has the same connecting rings. Both ends of the shaft 6 are fixedly connected to the shaft groove 61. There are two shafts 6. One shaft 6 passes through the four connecting rings on the primary check valve 3 and the secondary check valve 4, realizing the fixed connection between the primary check valve 3 and the secondary check valve 4. The other shaft 6 allows the primary check valve 3 and the secondary check valve 4 to rotate in from other directions.

[0020] The quick-change assembly 7 is connected between the outlet flange 8 and the secondary check valve 4 via positioning bolts 13. For example... Figure 5 As shown, the quick-change assembly 7 includes an upper support 10 and a lower support 9 that are mutually compatible. The lower surface of the lower support 9 contacts the secondary check valve 4, and its upper surface is provided with a placement groove and a connecting ring. The upper support 10 is also provided with a placement groove and a connecting ring; the connecting ring of the lower support 9 is located in the placement groove of the upper support 10, and the connecting ring of the upper support 10 is located in the placement groove of the lower support 9. An outer protective sleeve 11 is provided on the outer side of the connection between the lower support 9 and the upper support 10. The placement groove of the upper support 10 is provided with a positioning screw hole that is compatible with the positioning bolt 13. The positioning bolt 13 passes through the outlet flange 8 and the positioning screw hole on the upper support 10, fixing the two together. The tail end of the positioning bolt 13 abuts against the connecting ring of the lower support 9.

[0021] A high-pressure quick connector 17 is provided on the outer side of the lower support 9. The high-pressure quick connector 17 connects to a pressure device located outside the one-way valve assembly and has an oil passage inside that leads to the gap between the lower support 9 and the upper support 10. The lower support 9 also has a screw hole located in the connecting ring, and the upper support 10 has a spring groove 20 located in the placement slot for placing the return spring 12. The return spring 12 is composed of multiple springs connected in series. The screw hole and the spring groove 20 are on the same central axis, and a connecting hole is provided between the spring groove 20 and the screw hole. The diameter of the spring groove 20 is larger than the diameter of the connecting hole. The end of the spring groove 20 facing the upper support 10 is open, and a round cap is installed at the opening for sealing. The end of the screw hole facing the lower support 9 is closed. The adjusting bolt 18 passes through the spring groove 20 and the connecting hole in sequence, and finally passes into the screw hole. The adjusting bolt 18 has a stepped structure, and the diameter of its upper half is larger than the diameter of its lower half. The upper half of the adjusting bolt 18 is a smooth cylindrical body, and the lower half is threaded. The upper half of the adjusting bolt 18 has a diameter that matches the connecting hole, and the lower half has a diameter that matches the screw hole. The return spring 12 is sleeved on the upper half of the adjusting bolt 18 and is located in the spring groove 20.

[0022] The upper support 10 also has a support screw hole inside its placement groove for placing the support bolt 19. The tail end of the support bolt 19 abuts against the connecting ring of the lower support 9. Figure 6 As shown, the centers of the positioning bolt 13, adjusting bolt 18 and supporting bolt 19 are all distributed on the same circumference, and there are 4 of each.

[0023] A gap is maintained between the lower support 9 and the upper support 10. A guide ring assembly 15, an inner ring sealing assembly 14, and a high-pressure sealing assembly 16 are installed between them. The guide ring assembly 15 is an annular structure, fitted onto the inner ring formed by the groove in the lower support 9. When the lower support 9 and the upper support 10 move relative to each other, the guide ring assembly 15 guides the movement of either the lower support 9 or the upper support 10 in the vertical direction, either upwards or downwards. The inner ring sealing assembly 14 is an O-ring structure, fitted onto the end of the inner ring formed by the groove in the lower support 9 near the upper support 10, providing a seal. The high-pressure sealing assembly 16 is fitted onto the lower support 9 near the bottom of the groove. The upper and lower end faces of the inlet flange 1, the primary check valve 3, the secondary check valve 4, the quick-change assembly 7, and the outlet flange 8 are sealed by sealing rings 2.

[0024] Installation process of the check valve assembly: Use positioning bolts 13 to connect and install the quick-change assembly 7 to the outlet flange 8. When installing the primary check valve 3 and the secondary check valve 4, or when the valve cores of the primary check valve 3 and the secondary check valve 4 need to be replaced, connect the connecting rings of the primary check valve 3 and the secondary check valve 4 to be installed through the shaft 6 on one side, rotate them around the shaft 6 to enter the working position, and install and tighten the four fastening screw pairs 5 between the inlet flange 1 and the outlet flange 8, and confirm that the distance between the two flanges is met.

[0025] The working process of quick-change assembly 7: When disassembling the primary check valve 3 and the secondary check valve 4 to replace the valve core, the four fastening screw pairs 5 need to be loosened first, with a loosening distance greater than 15mm (the compression distance of each set of springs connected in series with adjusting bolts 18 is 5mm). The return spring 12 starts to return from the compressed state. The pressure device injects pressurized oil into the space between the lower support 9 and the upper support 10 inside the quick-change assembly 7 through the high-pressure quick connector 17, and the gap between the lower support 9 and the upper support 10 increases accordingly. The lower support 9 squeezes the primary check valve 3 and the secondary check valve 4 downward. When the compression limit distance is 15mm, the external pressure device is disconnected, and the pressurized oil is depressurized. At this time, the primary check valve 3 and the secondary check valve 4 can be easily rotated outward around the shaft 6. When installing the primary check valve 3 and the secondary check valve 4 after replacing the valve core, screw the shaft rod 6 of the primary check valve 3 and the secondary check valve 4 between the inlet flange 1 and the outlet flange 8, tighten the fastening screw pair 5, and the axial clearance between the lower support 9 and the upper support 10 is close to 0.

[0026] The pressurizing device injects pressurized oil into the quick-change assembly 7 through the high-pressure quick connector 17. To ensure sufficient preload on the screw assembly 5, the pressure of the pressurized oil in this embodiment is 50MPa to 60MPa. The pressurized oil flows between the lower support 9 and the upper support 10. After the pressurized oil, which carries its own pressure, enters the gap between the lower support 9 and the upper support 10, the upper and lower supports of the quick-change assembly 7 immediately extend by about 5mm (i.e., the compression distance of each set of springs connected in series with the adjusting bolts 18). Specifically, the pressurized oil applies downward pressure to the lower support 9, causing the lower support 9 to move downwards, increasing the gap between it and the upper support 10, while simultaneously compressing the return spring 12 by about 5mm. Tightening the four evenly distributed support bolts 19, the pressurized oil simultaneously applies preload to the support bolts 19, locking them in a locked state. The tail end of the support bolt 19 abuts against the lower support, thus maintaining a gap between the lower support 9 and the upper support 10. Install positioning bolts 13 to fix the upper support 10 to the outlet flange 8. Finally, disconnect the external pressure device to release the pressure of the pressurized oil. After the pressure of the pressurized oil disappears, the lower support 9 and the upper support 10 maintain a gap by means of support bolts 19.

Claims

1. A one-way valve device for a positive displacement reciprocating pump, characterized in that: Includes an inlet flange (1), an outlet flange (8), and a check valve assembly and quick-change assembly (7) installed between the inlet flange (1) and the outlet flange (8); The one-way valve assembly includes at least one shaft (6), and a first-stage one-way valve (3) and a second-stage one-way valve (4) connected in series. Both the first-stage one-way valve (3) and the second-stage one-way valve (4) have connecting rings on their outer sides. The shaft (6) is fixed between the inlet flange (1) and the outlet flange (8). One shaft (6) passes through the connecting ring at the same time, connecting the first-stage one-way valve (3) and the second-stage one-way valve (4) in series. The inlet flange (1) and the outlet flange (8) have through holes at their centers, which are respectively connected to the inlet of the first-stage one-way valve (3) and the outlet of the second-stage one-way valve (4), and the two are connected by a fastening screw pair (5). The quick-change assembly (7) is located between the check valve assembly and the outlet flange (8), and includes an adjusting bolt (18), a return spring (12), and an upper support (10) and a lower support (9) that are interlocked. Both the upper support (10) and the lower support (9) have through holes at their centers. The lower support (9) has a protruding connecting ring near its outer circumference and a recessed placement groove near its inner circumference. The upper support (10) has a placement groove that matches the connecting ring of the lower support (9) and a groove that matches the lower support. (9) Place a matching connecting ring; the upper support (10) has a spring groove (20) inside, and the lower support (9) has a screw hole coaxial with the spring groove (20) inside. The adjusting bolt (18) passes through the spring groove (20) and its tail end is fixed in the screw hole; the reset spring (12) is sleeved on the adjusting bolt (18) and located in the spring groove (20); the outer side of the lower support (9) is provided with a high-pressure quick connector (17) that communicates with the gap between the lower support (9) and the upper support (10); The upper support (10) is fixedly connected to the outlet flange (8) by positioning bolts (13); a support bolt (19) is also installed inside the upper support (10), and the tail end of the support bolt (19) abuts against the lower support (9) so that a gap is maintained between the upper support (10) and the lower support (9).

2. The one-way valve device for a positive displacement reciprocating pump according to claim 1, characterized in that: A connecting hole is also provided between the spring groove (20) and the screw hole, which is opened in the upper support (10). The diameter of the spring groove (20) is larger than the diameter of the connecting hole. The spring groove (20) is open at one end facing the upper support (10), and a round cover is provided at the opening for sealing; the screw hole is closed at one end facing the lower support (9).

3. The one-way valve device for a positive displacement reciprocating pump according to claim 2, characterized in that: The adjusting bolt (18) has a stepped structure, with the upper part having a larger diameter than the lower part; the upper part of the adjusting bolt (18) is a smooth cylindrical body with a diameter that matches the connecting hole; the lower part is provided with a thread that matches the screw hole.

4. The one-way valve device for a positive displacement reciprocating pump according to claim 3, characterized in that: The tail end of the positioning bolt (13) abuts against the lower support (9). The centers of the positioning bolt (13), the support bolt (19) and the adjusting bolt (18) are all located on the same circumference, which is distributed on the placement groove of the upper support (10).

5. A one-way valve device for a positive displacement reciprocating pump according to any one of claims 1-4, characterized in that: The outer side of the inlet flange (1) is provided with two shaft grooves (61) and multiple symmetrical screw grooves (51), and the multiple screw grooves (51) are symmetrically distributed about the diameter connected by the two shaft grooves (61); The depth of the screw groove (51) toward the center of the inlet flange (1) is greater than the depth of the shaft groove (61) toward the center of the inlet flange (1); the outlet flange (8) is provided with the same structure.

6. The one-way valve device for a positive displacement reciprocating pump according to claim 5, characterized in that: The connecting ring of the first-stage check valve (3) extends radially outward, and there are two of them, located at the upper and lower ends of the first-stage check valve (3) respectively. The second-stage check valve (4) has the same structure as the first-stage check valve (3). The primary check valve (3) is located near the inlet flange (1), and the secondary check valve (4) is located near the outlet flange (8).

7. A one-way valve device for a positive displacement reciprocating pump according to claim 6, characterized in that: A sealing ring (2) is provided between the primary check valve (3) and the inlet flange (1), between the secondary check valve (4) and the quick-change assembly (7), and between the quick-change assembly (7) and the outlet flange (8).

8. A one-way valve device for a positive displacement reciprocating pump according to claim 7, characterized in that: A guide ring assembly (15), an inner ring sealing assembly (14), and a high-pressure sealing assembly (16) are provided between the upper support (10) and the lower support (9). The guide ring assembly (15) is fitted in the middle of the inner ring formed by the placement groove of the lower support (9). The inner ring sealing assembly (14) is fitted at the end of the inner ring near the upper support (10), and the high-pressure sealing assembly (16) is fitted at the position of the inner ring near the bottom of the placement groove.

9. A one-way valve device for a positive displacement reciprocating pump according to claim 8, characterized in that: An outer protective sleeve (11) is fitted at the connection between the outer sides of the upper support (10) and the lower support (9).

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