Ultrahigh-pressure split type safety valve for fracturing

Abstract

The ultrahigh-pressure split type safety valve for fracturing is characterized in that a first inner through hole, a second inner through hole and a third inner through hole of which the diameters are sequentially increased and which are sequentially connected are formed in a valve body, and a first channel and a second channel are further formed in the valve body; the front end of the spring seat is in a through hole shape and is sequentially screwed into the third inner through hole and the second inner through hole in a threaded mode, the spring guide rod and the push rod are coaxially arranged in the spring seat, the spring guide rod is arranged in the spring seat by being sleeved with a spring push plate, one end of the push rod faces the spring guide rod, the other end of the push rod abuts against the steel ball, and the steel ball abuts against the first channel. The spring guide rod is sleeved with the disc spring set, one end of the disc spring set is fixedly connected to the spring guide rod, and the other end of the disc spring set abuts against the spring push plate; the split type push rod structure is adopted, and the disc spring is more convenient to install; a gap is formed between the push rod and the spring seat, the push rod is in a floating state, automatic alignment can be achieved when the push rod makes contact with the steel ball, the sealing face of the valve seat is in double-layer sealing, and reliability is high.

Description

Technical Field

[0001] The present invention relates to the field of ultra-high pressure safety valves, and more specifically, to an ultra-high pressure split safety valve for fracturing. Background Art

[0002] The safety valve for oilfield fracturing is an indispensable equipment to ensure the safety of fracturing construction. It is used to automatically release pressure when overpressure occurs to protect pipelines and equipment. At present, the ultra-high pressure safety valve for oilfield fracturing usually adopts an integral structure, that is, the push rod and the spring guide rod are integrated. Although this structure can meet the basic needs of oilfield fracturing, it has certain defects. The integrated push rod has a small circumferential floating range and cannot automatically align when in contact with the steel ball, resulting in the difficulty of the steel ball and the sealing surface of the valve seat to effectively fit, and the sealing effect is poor. The installation accuracy and manufacturing requirements of the steel ball and the valve seat are extremely high. Moreover, since the push rod and the spring guide rod are integrated, the spring is not easy to assemble, and the spring is prone to uneven force when under pressure, which leads to the phenomenon of premature jump of the safety valve. In addition, the existing integrated safety valves also have problems such as weak ability to withstand ultra-high pressure, inability to resist fluid erosion, and short service life. Summary of the invention

[0003] In order to achieve these purposes and other advantages according to the present invention, a preferred embodiment of the present invention provides an ultra-high pressure split safety valve for fracturing, comprising a spring guide rod, a spring push plate, a disc spring assembly, a spring seat, a push rod, a steel ball, a valve seat, a valve body, and a valve sleeve;

[0004] The valve body is provided with a first inner through hole, a second inner through hole, and a third inner through hole with diameters increasing in sequence and connected in sequence, and is also provided with a first channel and a second channel, the first channel and the second channel are vertically connected to each other, the first inner through hole is connected to the first channel, and the second inner through hole is connected to the second channel;

[0005] The spring seat has an internal space inside, the front end of the spring seat is in the shape of a through hole, and is screwed into the third internal through hole and the second internal through hole in sequence, the first passage of the valve body is connected to the internal space of the spring seat, the valve sleeve is fixedly sleeved on the front end of the spring seat extending into the valve body, the valve seat is fixed in the first internal through hole, the spring guide rod and the push rod are coaxially arranged in the spring seat, the spring guide rod is arranged in the spring seat through an externally sleeved spring push plate, one end of the push rod faces the spring guide rod, and the other end abuts against the steel ball, the steel ball abuts against the first passage and can block the first passage;

[0006] A disc spring assembly is sleeved on the spring guide rod, and one end of the disc spring assembly is fixedly connected to the spring guide rod, and the other end abuts against the spring push plate;

[0007] Wherein, the side of the valve seat close to the steel ball is inwardly concave to form a valve seat sealing surface, and the valve seat sealing surface is stepped, including a first sealing surface and a second sealing surface connected to each other, and the steel ball abuts against the first sealing surface and the second sealing surface;

[0008] High-pressure fluid flows into the first channel of the valve body, impacts the steel ball, and then squeezes the disc spring group. At this time, there will be a certain distance between the steel ball and the first channel to allow high-pressure fluid to flow through and out through the second channel.

[0009] Preferably, it further comprises an adjusting bolt, which is hollow inside and has one end open, and the open end of the adjusting bolt is sleeved on the spring guide rod;

[0010] It also includes a pressure regulating protective cover, which is sleeved on the outside of the adjusting bolt, and the pressure regulating protective cover is connected to the spring seat through a locking nut.

[0011] Preferably, it further comprises a bushing, which is sleeved on the outside of the steel ball, and the bushing covers the contact part between the steel ball and the push rod;

[0012] It also includes a valve seat sealing ring, which is located on the vertical end surface of the first inner through hole and abuts against the valve seat;

[0013] It also includes a retaining ring, a wing nut and a clamping ring. The wing nut is sleeved on the outside of the tail end of the valve body away from the spring guide rod through the retaining ring, and the clamping ring is surrounded between the wing nut and the retaining ring.

[0014] Preferably, the push rod portion is inserted into the spring seat, and a push rod sealing ring is circumferentially provided at the contact position between the two.

[0015] Preferably, a locking screw is provided at the threaded connection between the spring seat and the valve body to fix the spring seat and the valve body.

[0016] Preferably, a spring seat sealing ring is provided between the outer side surface of one end of the spring seat extending into the valve body and the inner wall of the valve body.

[0017] Preferably, the hardness of the push rod is lower than the hardness of the steel ball, and the push rod and the spring guide rod are made of different materials.

[0018] Preferably, the ends of the spring guide rod and the push rod that are close to each other are respectively sunken to form a limiting groove and protruded to form a limiting protrusion, the limiting protrusion is adapted to the limiting groove, and there is a gap between the limiting protrusion and the limiting groove.

[0019] Preferably, a surface of the push rod in contact with the steel ball is sunken to form an arc groove, and the steel ball is clamped in the arc groove, but the two are not completely fitted together, and a gap is formed between the arc groove and the steel ball.

[0020] The present invention includes at least the following beneficial effects: the ultra-high pressure split safety valve for fracturing of the present invention has a split push rod structure, and the disc spring is more convenient to install; wherein, there is a gap between the push rod and the spring seat, and there is a gap between the push rod and the spring guide rod, so the push rod has a radial floating amount, and the push rod is in a floating state. When subjected to axial force, the push rod presses the steel ball, and the steel ball contacts the valve seat. Under the action of extrusion, the push rod is aligned, so that the push rod, ball, and valve seat are coaxial, realizing the automatic alignment function of the steel ball, and finally the steel ball and the valve seat sealing surface can effectively contact to achieve reliable sealing.

[0021] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the structure of the ultra-high pressure split safety valve for fracturing in the present invention.

[0023] Figure 2 It is a structural schematic diagram of the valve seat in the present invention.

[0024] Pressure regulating protective cover 1, adjusting bolt 2, locking nut 3, spring guide rod 4, spring push plate 5, disc spring group 6, spring seat 7, push rod 8, bushing 9, steel ball 10, valve seat 11, valve seat sealing ring 12, valve body 13, retaining ring 14, wing nut 15, clamping ring 16, valve sleeve 17, spring seat sealing ring 18, push rod sealing ring 19, locking screw 20, first inner through hole 21, second inner through hole 22, third inner through hole 23, first channel 24 and second channel 25. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0026] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0027] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or position relationship indicated by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0028] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0029] like Figure 1-2 As shown, a preferred embodiment of the present invention provides an ultra-high pressure split safety valve for fracturing, comprising a spring guide rod 4, a spring push plate 5, a disc spring group 6, a spring seat 7, a push rod 8, a steel ball 10, a valve seat 11, a valve body 13, and a valve sleeve 17;

[0030] The valve body 13 is provided with a first inner through hole 21, a second inner through hole 22, a third inner through hole 23, a first channel 24 and a second channel 25 with increasing diameters in sequence and connected in sequence. The first channel 24 and the second channel 25 are perpendicular to each other. The first inner through hole 21 is connected to the first channel 24, and the second inner through hole 22 is connected to the second channel 25.

[0031] The spring seat 7 has an internal space, the front end of the spring seat 7 is in the shape of a through hole, and is screwed into the third internal through hole 23 and the second internal through hole 22 in sequence, the first passage 24 of the valve body 13 is connected to the internal space of the spring seat 7, the valve sleeve 17 is fixedly sleeved on the front end of the spring seat 7 extending into the valve body 13, and the valve seat 11 is fixed in the first internal through hole 21;

[0032] The spring guide rod 4 and the push rod 8 are coaxially arranged in the spring seat 7. The spring guide rod 4 is arranged in the spring seat 7 through an external spring push plate 5. One end of the push rod 8 faces the spring guide rod 4, and the other end abuts against the steel ball 10. The steel ball 10 abuts against the first channel and can block the first channel. There is a gap between the spring seat 7 and the push rod 8, and a bushing 9 is provided at one end of the second channel 25 connected to the second inner through hole 22.

[0033] A disc spring assembly 6 is sleeved on the spring guide rod 4, and one end of the disc spring assembly 6 is fixedly connected to the spring guide rod 4, and the other end abuts against the spring push plate 5;

[0034] The ends of the spring guide rod 4 and the push rod 8 that are close to each other are respectively sunken inward to form a limiting groove and protruded to form a limiting protrusion. The limiting protrusion is adapted to the limiting groove, and the connection is more stable. There is a gap between the limiting protrusion and the limiting groove.

[0035] In the above technical solution, the high-pressure fluid flows in from the first channel 24 of the valve body 13, and the high-pressure fluid impacts the steel ball 10, thereby squeezing the disc spring group 6, pushing the disc spring group 6 to the left and compressing it. At this time, the steel ball 10 and the first channel 24 will be at a certain distance to form a flow channel for the high-pressure liquid to flow through and flow out through the second channel 25. The impact generated by the high-pressure fluid must be greater than the elastic force of the spring itself, so that the steel ball will be squeezed and flushed, so that the fluid will also flow out through the second channel 25, otherwise it cannot be flushed open, and the above-mentioned steel ball 10 will block the first channel, so that the entire valve plays a sealing role.

[0036] In the above technical solution, there is a gap between the push rod 8 and the spring seat, and there is a gap between the push rod 8 and the spring guide rod 4, so the push rod has a radial floating amount. When the push rod is in a floating state and is subjected to axial force, the push rod presses the steel ball, and the steel ball contacts the valve seat. Under the action of extrusion, the push rod is aligned, so that the push rod, ball, and valve seat are coaxial, realizing the automatic alignment function of the steel ball, and finally the steel ball and the valve seat sealing surface can effectively contact to achieve reliable sealing.

[0037] Moreover, the split push rod structure is adopted, which makes the installation of the disc spring group 6 more convenient. The disc spring group 6 can be directly mounted on the spring guide rod 4; a spring push plate 5 is provided at the end of the disc spring group 6, which is mounted on the spring guide rod 4 and is used to resist the disc spring group 6.

[0038] In another technical solution, the ultra-high pressure split safety valve for fracturing further comprises an adjusting bolt 2, which is hollow inside and has one end open, and the open end of the adjusting bolt 2 is sleeved on the spring guide rod 4. The front end of the push rod 8 is sleeved with a valve sleeve 17.

[0039] In another technical solution, the ultra-high pressure split safety valve for fracturing further includes a pressure regulating protective cover 1, which is sleeved on the outside of the adjusting bolt 2, and the pressure regulating protective cover 1 is connected to the spring seat 7 through a locking nut 3.

[0040] Another technical solution further includes a bushing 9 which is sleeved on the outside of the steel ball 10 , and the bushing 9 covers the contact portion between the steel ball 10 and the push rod 8 .

[0041] When the fluid pressure is too high, the disc spring group 6 is pushed to the left at the moment, and the small gap and the high-pressure fluid collide at the moment, which may cause the push rod 8 to be violently opened and damaged. Therefore, a bushing 9 is arranged between the steel ball 10 and the push rod 8 to play a certain blocking and buffering role.

[0042] Another technical solution further includes a valve seat sealing ring 12 , which is located on the vertical end surface of the first inner through hole 21 and abuts against the valve seat 11 .

[0043] In the above technical solution, the vertical end face of the first inner through hole 21 is sunken to form an annular sealing groove, the valve seat sealing ring 12 is annular and embedded in the annular sealing groove, and the surface of the valve seat sealing ring 12 protrudes from the top of the sealing groove, and the valve seat sealing ring 12 is made of rubber material. In this way, the valve seat sealing ring 12 can play a certain sealing role on the water flow, preventing the water flow from flowing out from between the valve seat 11 and the vertical end face of the first inner through hole 21. Because the valve seat 11 and the first inner through hole 21 are both made of hard steel, absolute sealing cannot be achieved between the two.

[0044] Another technical solution further includes a retaining ring 14, a wing nut 15 and a clamping ring 16. The wing nut 15 is sleeved on the outside of the tail end of the valve body 13 away from the spring guide rod 4 through the retaining ring 14, and the clamping ring 16 is surrounded between the wing nut 15 and the retaining ring 14. The retaining ring 14, the wing nut 15, the clamping ring 16 and the valve body 13 together form a whole.

[0045] In another technical solution, the push rod 8 is partially inserted into the spring seat 7, and a push rod sealing ring 19 is circumferentially provided at the contact portion between the push rod 8 and the spring seat 7 to further seal the gap between the push rod 8 and the spring seat 7.

[0046] In another technical solution, a locking screw 20 is provided at the threaded connection between the spring seat 7 and the valve body 13 to fix the spring seat 7 and the valve body 13 firmly.

[0047] In another technical solution, a spring seat sealing ring 18 is provided between the outer side surface of one end of the spring seat 7 extending into the valve body 13 and the inner wall of the valve body 13 to play a further sealing role.

[0048] In another technical solution, the spring guide rod 4 is hollow inside and adopts a light-weight hollow structure, so the inertia of take-off is small and the take-off is more accurate.

[0049] In another technical solution, one side of the valve seat 11 close to the steel ball is recessed inward to form a valve seat sealing surface. The valve seat sealing surface is stepped, including a first sealing surface 11-1 and a second sealing surface 11-2 connected to each other. The steel ball abuts against the first sealing surface and the second sealing surface. In this way, the two sealing surfaces can be used to achieve secondary sealing of the steel ball, resulting in a better sealing effect.

[0050] In another technical solution, the hardness of the push rod 8 is lower than the hardness of the steel ball, so as not to damage the sealing surface of the steel ball.

[0051] In another technical solution, the push rod 8 and the spring guide rod 4 are made of different materials. Only the push rod 8 with higher hardness requirement needs to be made of high hardness material, while the spring guide rod 4 can be made of general steel material, thereby reducing costs.

[0052] In another technical solution, the side of the push rod 8 that contacts the steel ball is sunken to form an arc groove, and the steel ball 10 is stuck in the arc groove, but the two are not completely fitted, and a gap is formed between the arc groove and the steel ball 10.

[0053] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. An ultra-high pressure split safety valve for fracturing, characterized in that: It includes a spring guide rod, a spring push plate, a disc spring assembly, a spring seat, a push rod, a steel ball, a valve seat, a valve body, and a valve sleeve; The valve body is provided with a first inner through hole, a second inner through hole, and a third inner through hole with diameters increasing in sequence and connected in sequence, and is also provided with a first channel and a second channel, the first channel and the second channel are vertically connected to each other, the first inner through hole is connected to the first channel, and the second inner through hole is connected to the second channel; The spring seat has an internal space inside, the front end of the spring seat is in the shape of a through hole, and is screwed into the third internal through hole and the second internal through hole in sequence, the first passage of the valve body is connected to the internal space of the spring seat, the valve sleeve is fixedly sleeved on the front end of the spring seat extending into the valve body, the valve seat is fixed in the first internal through hole, the spring guide rod and the push rod are coaxially arranged in the spring seat, the spring guide rod is arranged in the spring seat through an externally sleeved spring push plate, one end of the push rod faces the spring guide rod, and the other end abuts against the steel ball, the steel ball abuts against the first passage and can block the first passage; A disc spring assembly is sleeved on the spring guide rod, and one end of the disc spring assembly is fixedly connected to the spring guide rod, and the other end abuts against the spring push plate; Wherein, the side of the valve seat close to the steel ball is inwardly concave to form a valve seat sealing surface, and the valve seat sealing surface is stepped, including a first sealing surface and a second sealing surface connected to each other, and the steel ball abuts against the first sealing surface and the second sealing surface; High-pressure fluid flows into the first channel of the valve body, impacts the steel ball, and then squeezes the disc spring group. At this time, there will be a certain distance between the steel ball and the first channel to allow high-pressure fluid to flow through and out through the second channel.

2. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: It also includes an adjusting bolt, which is hollow inside and has one end open, and the open end of the adjusting bolt is sleeved on the spring guide rod; It also includes a pressure regulating protective cover, which is sleeved on the outside of the adjusting bolt, and the pressure regulating protective cover is connected to the spring seat through a locking nut.

3. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: It also includes a bushing, which is sleeved on the outside of the steel ball, and the bushing covers the contact part between the steel ball and the push rod; It also includes a valve seat sealing ring, which is located on the vertical end surface of the first inner through hole and abuts against the valve seat; It also includes a retaining ring, a wing nut and a clamping ring. The wing nut is sleeved on the outside of the tail end of the valve body away from the spring guide rod through the retaining ring, and the clamping ring is surrounded between the wing nut and the retaining ring.

4. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: The push rod portion is inserted into the spring seat, and a push rod sealing ring is circumferentially arranged at the contacting position of the two.

5. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: A locking screw is provided at the threaded connection point between the spring seat and the valve body to fix the spring seat and the valve body.

6. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: A spring seat sealing ring is provided between the outer side surface of one end of the spring seat extending into the valve body and the inner wall of the valve body.

7. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: The hardness of the push rod is lower than that of the steel ball, and the push rod and the spring guide rod are made of different materials.

8. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: The ends of the spring guide rod and the push rod that are close to each other are respectively sunken to form a limiting groove and protruded to form a limiting protrusion. The limiting protrusion is adapted to the limiting groove, and there is a gap between the limiting protrusion and the limiting groove.

9. The ultra-high pressure split safety valve for fracturing according to claim 1, characterized in that: The side of the push rod in contact with the steel ball is sunken to form an arc groove, and the steel ball is clamped in the arc groove, but the two are not completely fitted together, and a gap is formed between the arc groove and the steel ball.

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