Gear motor direct drive dual control axial flow mechanical pilot water hammer pressure relief valve

Abstract

The present invention belongs to the technical field of water hammer pressure relief valves, and specifically relates to a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, including a valve body, a support cylinder, a gear motor, a valve stem, a mechanical pilot valve, and a handwheel. The support cylinder is fixed on the valve body, and a sealing end cover is provided on the support cylinder. The valve body includes an inlet and an outlet; the valve stem passes through the support cylinder, the sealing end cover and the gear motor, and a plug is provided at one end of the valve stem, and the other end is connected to the handwheel; the plug extends into the valve body, and the inlet axis of the valve body is perpendicular to the axis of the valve stem; the valve stem is provided with an external thread section near the plug, and the external thread section is meshed with the internal thread provided on the support cylinder. The present invention uses a mechanical pilot valve to automatically and manually control the gear motor to directly drive the valve stem, thereby achieving accurate control of the valve caliber and automatic adjustment, thereby making the pressure relief valve fast to start, easy to adjust, safer and more reliable, and longer in service life.

Description

Technical Field

[0001] The invention belongs to the technical field of water hammer pressure relief valves, and in particular relates to a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor. Background Art

[0002] In long-distance oil pipelines, unexpected pump stoppage or abnormal valve opening and closing can cause water hammer, which may cause local overpressure in the pipeline and cause pipe burst accidents. In order to ensure the safe operation of long-distance oil pipelines and related equipment, water hammer pressure relief valves are usually used to release water hammer pressure.

[0003] When water hammer occurs in the pipeline, the pressure relief valve can open quickly and release the high-pressure medium to restore the pipeline pressure to the normal range, thereby protecting the pipeline and the equipment in the pipeline. Therefore, the opening speed of the pressure relief valve when water hammer occurs is of great significance to the safe operation of the entire pipeline.

[0004] At present, traditional water hammer pressure relief valves mainly include three structural forms: angle type, axial flow type and Y type. In principle, the normal operation of the main valve is ensured by the pressure change in the main valve cavity and the main valve spring. They generally have the following defects:

[0005] 1. The main valve cavity is connected to the front and rear pipelines through the pilot valve. When the main valve cavity is actuated, the liquid in the main valve cavity needs to be discharged. Due to the limitations of the pilot valve structure and the diameter of the pressure-inducing pipe, the liquid discharge speed in the main valve cavity is slow, so that the main valve cannot be opened quickly;

[0006] 2. The oil needs to flow through the main valve cavity, so the requirements for the liquid medium are high, and a filter needs to be installed, so that the traditional water hammer pressure relief valve can only be used for long-distance pipelines of refined oil, limiting its application scenarios;

[0007] 3. Due to the existence of the main valve spring, the valve core will vibrate during operation, which will aggravate the wear of the valve core and shorten its service life. Summary of the invention

[0008] In order to solve the problems existing in the above-mentioned background technology, the present invention proposes a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, which can automatically and manually control the gear motor to directly drive the valve stem through a mechanical pilot valve, thereby realizing accurate control of the valve diameter and automatic adjustment, thereby making the pressure relief valve have a fast starting speed, convenient adjustment, higher safety and reliability, and longer service life.

[0009] The technical solution of the present invention to achieve the above functions is: a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, which is special in that:

[0010] Including valve body, support cylinder, gear motor, valve stem, mechanical pilot valve, hand wheel,

[0011] The support cylinder is fixed on the valve body, and a sealing end cover is provided on the support cylinder. The valve body includes an inlet and an outlet;

[0012] The valve stem passes through the support cylinder, the sealing end cover and the gear motor. One end of the valve stem is provided with a plug, and the other end is connected to the hand wheel. The plug extends into the valve body, and the inlet axis of the valve body is perpendicular to the axis of the valve stem.

[0013] An external thread section is provided near the plug on the valve stem, and the external thread section is meshed with an internal thread provided on the support tube;

[0014] The gear motor includes a housing, a first gear and a second gear. The housing is provided with an oil suction port and an oil outlet.

[0015] The inlet of the valve body is connected to the oil inlet of the mechanical pilot valve through the first stop valve, and the oil discharge port of the mechanical pilot valve is connected to the outlet of the valve body; the oil suction port and oil outlet of the gear motor are respectively connected to the two working ports of the mechanical pilot valve through pipelines, and a second stop valve is installed between the two pipelines.

[0016] Furthermore, the valve stem and the first gear are connected via a spline.

[0017] Furthermore, the first gear is provided with an internal spline, and the valve stem is provided with an external spline.

[0018] Furthermore, a sealing ring is installed between the support tube and the valve body.

[0019] Furthermore, the support tube is provided with a cavity, a packing cavity is formed between the inner wall of the cavity and the valve stem, and the sealing end cover presses the packing in the packing cavity through a packing gland.

[0020] Furthermore, the hand wheel is fixed on the valve stem through a nut.

[0021] Furthermore, a gasket for preventing loosening is provided between the handwheel and the nut.

[0022] Furthermore, the hand wheel is provided with a mounting hole, the valve stem passes through the mounting hole, and the mounting hole limits the hand wheel.

[0023] Advantages of the present invention:

[0024] 1. The oil inlet of the main valve body is connected to the oil outlet of the valve body through the pilot valve and the gear motor. When in action, the valve stem is directly driven to rotate by the gear motor, thereby driving the valve disc to move and directly adjusting the size of the valve body bore. It can start and close quickly during the process of oil discharge and pressure relief.

[0025] 2. The gear motor is controlled by both automatic and manual modes of the mechanical pilot valve to realize the opening and closing of the valve. When the mechanical pilot valve fails, the pressure relief valve can still be opened by manually turning the hand wheel, thereby improving the reliability of the pressure relief valve control. The gear motor can output a large torque to realize the accurate opening of the valve, thereby improving the accuracy of the valve opening.

[0026] 3. The traditional main valve spring is replaced by the engagement of the valve stem and the support cylinder to avoid valve core vibration during operation and increase the service life of the pressure reducing valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the main structure of a dual-control shaft flow water hammer pressure relief valve directly driven by a gear motor proposed by the present invention, with the valve port closed;

[0028] Figure 2 It is a schematic diagram of the structure of the gear motor;

[0029] Figure 3 It is a schematic diagram of the main structure of a dual-control shaft flow water hammer pressure relief valve directly driven by a gear motor proposed by the present invention, with the valve port open;

[0030] In the figure: 1. valve body, 2. plug, 3. valve stem, 4. sealing ring, 5. support cylinder, 6. packing, 7. packing gland, 8. sealing end cover, 9. gear motor, 10. hand wheel, 11. gasket, 12. nut, 13. second stop valve, 14. mechanical pilot valve, 15. first stop valve, 91. first gear, 92. secondary shaft, 93. oil outlet, 94. second gear, 96. oil suction port. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0032] A dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, comprising a valve body 1, a support cylinder 5, a gear motor 9, a valve stem 3, a mechanical pilot valve 14, and a hand wheel 10. The support cylinder 5 is fixed on the valve body 1, and a sealing end cover 8 is provided on the support cylinder 5. The valve body 1 comprises an inlet and an outlet.

[0033] The valve stem 3 passes through the support tube 5, the sealing end cover 8 and the gear motor 9. One end of the valve stem 3 is provided with a plug 2, and the other end is connected to the handwheel 10; the plug 2 extends into the valve body 1, and the inlet axis of the valve body 1 is perpendicular to the axis of the valve stem 3; the valve stem 3 is provided with an external thread section near the plug 2, and the external thread section is engaged with the internal thread provided in the support tube 5; the gear motor 9 includes a shell 73 and a first gear 91 and a second gear 94. The shell 73 is provided with an oil suction port 96 and an oil outlet port 93. The inlet of the valve body 1 is connected to the oil inlet of the mechanical pilot valve 14 through the first stop valve 15, and the oil outlet of the mechanical pilot valve 14 is connected to the outlet of the valve body 1; the oil suction port 96 and the oil outlet port 93 of the gear motor 9 are respectively connected to the two working ports of the mechanical pilot valve 14 through pipelines, and a second stop valve 13 is installed between the two pipelines.

[0034] As a preferred embodiment of the present invention, the first gear 91 is provided with an internal spline, the valve stem 3 is provided with an external spline, and the valve stem 3 and the first gear 91 are connected via a sliding spline. The spline connection ensures that the valve stem 3 can move up and down while the first gear 91 drives the valve stem 3 to rotate.

[0035] As a preferred embodiment of the present invention, a sealing ring 4 is installed between the support tube 5 and the valve body 1 .

[0036] A packing 6 is provided between the valve stem 3 and the support tube 5. The support tube 5 is provided with a cavity, and a packing cavity is formed between the inner wall of the cavity and the valve stem 3, and the sealing end cover 8 presses the packing 6 in the packing cavity through the packing gland 7.

[0037] As a preferred embodiment of the present invention, the hand wheel 10 is fixed on the valve stem 3 by a nut 12. A gasket 11 for preventing loosening is provided between the hand wheel 10 and the nut 12. A mounting hole is provided on the hand wheel 10, and the valve stem 3 passes through the mounting hole, and the mounting hole limits the hand wheel 10.

[0038] Example:

[0039] like Figure 1 to Figure 3As shown, a double-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor 9 includes a water hammer pressure relief valve body 1, an internal threaded portion of a support tube 5 with an internal thread is meshed with a plug 2, a support tube 5 with an internal thread is installed on the valve body 1, a sealing ring 4 is installed between the support tube 5 with the internal thread and the water hammer pressure relief valve body 1, the outer side of the valve stem 3 where the plug 2 is located and the interior of the support tube 5 with the internal thread form a stuffing cavity, a stuffing 6 is installed in the stuffing cavity, the stuffing 6 is pressed in the support tube 5 through a sealing end cover 8 and a stuffing gland 7, a hand wheel 10 is installed on the valve stem 3, a gear motor 9 for driving the plug 2 and the valve stem 3 is installed between the sealing end cover 8 and the hand wheel 10, and a nut 12 and a gasket 11 for fixing the hand wheel 10 are installed on the valve stem 3. The inlet of the valve body 1 is connected to the oil inlet of the mechanical pilot valve 14 through the first stop valve 15, and the oil outlet of the mechanical pilot valve 14 is connected to the outlet of the valve body 1; the oil suction port 96 and the oil outlet 93 of the gear motor 9 are respectively connected to the two working ports of the mechanical pilot valve 14 through pipelines, and a second stop valve 13 is installed between the two pipelines.

[0040] The valve body 1 is an axial flow valve body, that is, the inlet axis of the valve body 1 is perpendicular to the axis of the valve stem 3 .

[0041] The gear motor 9 can adopt an existing gear motor 9. The gear motor 9 includes a housing, a first gear 91, a second gear 94, an oil suction port 96 and an oil outlet 93. The first gear 91 is provided with an internal spline, and the valve stem 3 is provided with an external spline. The valve stem 3 and the first gear 91 are connected by a sliding spline. The spline connection ensures that the valve stem 3 can move up and down while the first gear 91 drives the valve stem 3 to rotate. The second gear 94 is fixed on the secondary shaft 92.

[0042] The mechanical pilot valve 14 is in the left position during normal operation, and the oil in the pipeline enters the oil suction port 96 of the gear motor 9 through the working port of the mechanical pilot valve 14, causing the gear motor 9 to rotate clockwise, keeping the main valve closed. When the oil pressure continues to rise and exceeds the spring set pressure, the oil pressure pushes the valve core to make the mechanical pilot valve 14 work in the right position, and the oil pressure in the pipeline enters the oil outlet 93 of the gear motor 9 to absorb oil, causing the gear motor 9 to rotate counterclockwise, opening the main valve, thereby playing a role in overpressure safety relief.

[0043] The hand wheel 10 is another way to drive the plug 2 to prevent the gear motor 9 from failing to release pressure normally due to a fault in the direct drive mode. When the gear motor 9 is working normally, the second stop valve 13 is closed, and when the gear motor 9 fails, the second stop valve 13 needs to be opened to close the first stop valve 15, and then the hand wheel 10 is turned to drive the plug 2 to move upward to open the valve port to achieve the purpose of pressure relief.

[0044] The working principle of the present invention is:

[0045] During the normal oil transportation process in the pipeline, the water hammer pressure relief valve is in a closed state. When water hammer occurs in the pipeline, the oil at the location where the water hammer occurs is compressed in volume, and the oil pressure rises rapidly and spreads along the pipeline. The inlet end of the valve body 1 is connected to the main oil pipeline, and the outlet end is connected to the oil tank to receive the oil discharged by pressure relief.

[0046] 1) Gear motor 9 drives pressure relief mode:

[0047] Under normal circumstances, the second stop valve 13 is in a closed state, and the first stop valve 15 is in an open state. The pressure threshold of the mechanical pilot valve 14 is set to 10MPa. When the pressure threshold in the oil pipeline is less than 10MPa, the pressure relief valve always remains in a closed state. Figure 1 .

[0048] When the liquid pressure in the valve cavity is lower than the pressure set by the mechanical pilot valve 14, the mechanical pilot reversing valve is in the left working state, and the oil in the pipeline enters the oil suction port 96 of the gear motor 9 through the mechanical pilot valve 14, causing the first gear 91 of the gear motor 9 to rotate clockwise, and the valve stem 3 moves down to close the main valve. When the pressure in the pipeline suddenly rises and exceeds the set pressure of the mechanical pilot valve 14, see Figure 3 , which proves that water hammer has occurred in the pipeline. The oil pressure pushes the valve core to make the mechanical pilot reversing valve 12 work in the right position. The oil pressure in the pipeline enters the oil outlet 93 of the gear motor 9, causing the first gear 91 of the gear motor 9 to rotate counterclockwise and drive the plug 2 to move upward to open the valve port, thereby achieving overpressure safety relief.

[0049] 2) Handwheel driven pressure relief mode:

[0050] When the gear motor 9 and the mechanical pilot valve 14 fail, it is necessary to open the second stop valve 13, close the first stop valve 15, and then use the hand wheel 10 to drive the valve stem 3 to open or close the main valve, so that the inlet and outlet of the water hammer relief valve body 1 are connected, and the high-pressure oil flows from the inlet to the outlet, thereby reducing the oil pressure in the pipeline and achieving the effect of pressure relief.

[0051] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent protection scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention's specification and drawings, or directly or indirectly applied in other related system fields, are also included in the patent protection scope of the present invention.

Claims

1. A dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor. Features: It comprises a valve body (1), a support cylinder (5), a gear motor (9), a valve stem (3), a mechanical pilot valve (14), and a hand wheel (10). The support cylinder (5) is fixed on the valve body (1), a sealing end cover (8) is provided on the support cylinder (5), and the valve body (1) comprises an inlet and an outlet; The valve stem (3) passes through the support tube (5), the sealing end cover (8) and the gear motor (9); one end of the valve stem (3) is provided with a plug (2), and the other end is connected to the hand wheel (10); the plug (2) extends into the valve body (1), and the inlet axis of the valve body (1) is perpendicular to the axis of the valve stem (3); The valve stem (3) is provided with an external thread section near the plug (2), and the external thread section is meshed with the internal thread provided on the support tube (5); The gear motor (9) comprises a housing, a first gear (91) and a second gear (94); the housing is provided with an oil suction port (96) and an oil outlet port (93); the first gear (91) drives the valve stem (3) to rotate; The inlet of the valve body (1) is connected to the oil inlet of the mechanical pilot valve (14) through a first stop valve (15), and the oil outlet of the mechanical pilot valve (14) is connected to the outlet of the valve body (1); the oil suction port (96) and the oil outlet (93) of the gear motor (9) are respectively connected to the two working ports of the mechanical pilot valve (14) through pipelines, and a second stop valve (13) is installed between the two pipelines.

2. According to claim 1, a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, Features: The valve stem (3) and the first gear (91) are connected via a spline.

3. According to claim 2, a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, Features: The first gear (91) is provided with an internal spline, and the valve stem (3) is provided with an external spline.

4. According to claim 3, a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, Features: A sealing ring (4) is installed between the support cylinder (5) and the valve body (1).

5. According to claim 4, a dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor, Features: The support cylinder (5) is provided with a cavity, a packing cavity is formed between the inner wall of the cavity and the valve stem (3), and the sealing end cover (8) presses the packing (6) in the packing cavity through the packing gland (7).

6. A dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor according to claim 5, Features: The hand wheel (10) is fixed on the valve stem (3) via a nut (12).

7. A dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor according to claim 6, Features: A gasket (11) for preventing loosening is provided between the hand wheel (10) and the nut (12).

8. A dual-control axial flow mechanical pilot water hammer pressure relief valve directly driven by a gear motor according to claim 7, Features: The hand wheel (10) is provided with a mounting hole, the valve stem (3) passes through the mounting hole, and the mounting hole limits the position of the hand wheel (10).

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