Blowout prevention device for unbalanced drilling

Abstract

The utility model relates to the technical field of well drilling, and particularly discloses a blowout prevention device for unbalanced well drilling. Comprising a first valve body and a second valve body; a first connecting plate and a second connecting plate are arranged on one side of the first valve body and one side of the second valve body; the first valve body and the first connecting plate are integrally arranged, and the second valve body and the second connecting plate are integrally arranged. The first air cylinder body and the second air cylinder body are arranged on the two sides of the second main valve body correspondingly and communicate with the second main valve body. A third blowout prevention piece and a fourth blowout prevention piece are arranged in the third air cylinder body and the fourth air cylinder body respectively. The third blowout prevention piece and the fourth blowout prevention piece are combined to form a semi-closed blowout prevention piece; and the first main valve body is communicated with the second main valve body. According to the underbalanced drilling blowout prevention device, the combined design of the totally-closed blowout prevention piece and the semi-closed blowout prevention piece is adopted, and the blowout prevention effect is effectively improved. And the air cylinder body is communicated with the main valve body, so that the balance of working conditions is kept, and the risk of accidental ejection is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of drilling, in particular to an underbalanced drilling blowout prevention device. Background Art

[0002] Under-balanced drilling is a drilling technology characterized by the fact that the bottom hole pressure is lower than the formation pressure during the drilling process, allowing the formation fluid (usually oil, gas or water) around the wellbore to enter the wellbore, thereby reducing or avoiding the invasion of the drilling fluid into the formation, which is beneficial to protecting the formation core and improving drilling efficiency. Under-balanced drilling reduces the invasion and damage to the formation, which is beneficial to maintaining the natural productivity of the formation and improving the oil and gas recovery rate. However, under-balanced drilling also has certain challenges and risks, such as easy to cause blowouts, wellbore collapse and formation instability, which requires strict design and operation to ensure drilling safety and success.

[0003] In the process of underbalanced drilling, it is very important to prevent blowouts, because blowouts may cause serious harm to underground workers and drilling equipment. Now, the use of drilling fluid separation devices (BOP), rotating drill pipe blowout preventers (RotatingControl Device, RCD) or downhole blowout preventer valves (Down hole Safety Valve) to avoid blowouts can effectively deal with the risk of blowouts. It is also possible to close the wellbore when a blowout occurs to reduce the harm of blowouts. These devices and equipment play a vital role in underbalanced drilling to ensure that drilling operations are carried out safely and stably.

[0004] A blowout preventer is disclosed in the patent "Annular Blowout Preventer" (publication number CN203239271U, hereinafter referred to as prior art 1). The annular blowout preventer in prior art 1 includes a shell and an upper cover, wherein the shell is separated by an intermediate ring to form a hydraulic cylinder, a piston is arranged in the hydraulic cylinder, a rubber core is abutted on the piston, the upper cover is fixed to the mounting surface of the shell by bolts, and a first groove is provided on the mounting surface of the shell corresponding to the upper cover, and a limit block for preventing the intermediate ring from being pulled out of the shell is provided in the first groove. The sealing mechanism in prior art 1 is installed between the contact surface of the piston and the shell and / or between the contact surface of the piston and the intermediate ring, and includes a dust ring and a sealing ring. The hydraulic cylinder is divided by the piston into two mutually isolated cavities for containing hydraulic fluid, namely a closed cavity and an open cavity, the closed cavity has a first opening, the open cavity has a second opening, the accumulator is connected to the second opening through a rubber hose, and the hydraulic fluid flows from the closed cavity to the accumulator. A lifting lug for lifting the annular blowout preventer is installed on the upper cover. Prior art 1 prevents mud and sand from invading the hydraulic cylinder and ensures the fixed position of the piston and the housing by setting a sealing mechanism and a limit block, thereby improving the sealing performance and use reliability of the annular blowout preventer. However, in prior art 1, only a single blowout prevention means is set, and only a fully closed or semi-closed blowout prevention mode can be set. The blowout prevention means is single and has low flexibility. Utility Model Content

[0005] In view of this, an embodiment of the utility model provides an underbalanced drilling blowout prevention device to solve the problem of single blowout prevention means and low flexibility in the prior art.

[0006] The utility model embodiment provides an underbalanced drilling blowout prevention device, including a first valve body and a second valve body; a first connecting plate and a second connecting plate are provided on one side of the first valve body and the second valve body; the first valve body and the second valve body are respectively integrated with the first connecting plate and the second connecting plate; the first valve body includes a first main valve body connecting the first cylinder body and the second cylinder body; the first cylinder body and the second cylinder body are respectively arranged on both sides of the first main valve body and are connected to the first main valve body; a first blowout preventer and a second blowout preventer are respectively provided in the first cylinder body and the second cylinder body; the first blowout preventer and the second blowout preventer are combined to form a fully enclosed blowout preventer; the second valve body includes a second main valve body connecting the third cylinder body and the fourth cylinder body; the first cylinder body and the second cylinder body are respectively arranged on both sides of the second main valve body and are connected to the second main valve body; a third blowout preventer and a fourth blowout preventer are respectively provided in the third cylinder body and the fourth cylinder body; the third blowout preventer and the fourth blowout preventer are combined to form a semi-enclosed blowout preventer; the first main valve body and the second main valve body are connected.

[0007] Preferably, a cavity is provided inside the first main valve body and the second main valve body; through holes or openings are provided on the side walls of the first main valve body and the second main valve body; flanges are provided outside the places where the through holes or openings are provided.

[0008] Preferably, the first main valve body and the second main valve body are connected via through holes or openings provided at both ends.

[0009] Preferably, two ends of the first main valve body and the second main valve body after being connected are respectively provided with a first connecting flange and a second connecting flange.

[0010] Preferably, the first and second blowout preventers are connected at one end, and are both provided with a piston rod at the other end; the third and fourth blowout preventers are connected at one end, and are both provided with a piston rod at the other end.

[0011] Preferably, the first cylinder block, the second cylinder block, the third cylinder block and the fourth cylinder block are all provided with cavities inside; the cavities inside the first cylinder block, the second cylinder block, the third cylinder block and the fourth cylinder block are respectively the accommodating cavities of the first blowout preventer, the second blowout preventer, the third blowout preventer and the fourth blowout preventer.

[0012] Preferably, the first cylinder block and the second cylinder block are provided with a first cylinder flange and a second cylinder flange at one end respectively; the third cylinder block and the fourth cylinder block are provided with a third cylinder flange and a fourth cylinder flange at one end respectively.

[0013] Preferably, the piston rods arranged in the first cylinder body, the second cylinder body, the third cylinder body and the fourth cylinder body all extend to the inside of the first cylinder flange, the second cylinder flange, the third cylinder flange and the fourth cylinder flange.

[0014] Preferably, the first cylinder body, the second cylinder body, the third cylinder body and the fourth cylinder body are all provided with a piston cavity; the piston cavity is provided with a piston body; the cylinder rod is provided in the piston body; and the piston body is adapted to the piston cavity.

[0015] Preferably, a slot is provided at one end of the first, second, third and fourth blowout preventer connected to the piston rod; a protrusion adapted to the slot is provided at one end of the piston rod connected to the first, second, third and fourth blowout preventer.

[0016] The underbalanced drilling blowout prevention device provided by the utility model has the following beneficial effects:

[0017] The present application significantly improves the stability and reliability of the device through the integrated arrangement of the first valve body and the second valve body and the first connecting plate and the second connecting plate. This integrated structure not only enhances the overall strength of the device, but also makes installation and maintenance easier and faster. The first cylinder body and the second cylinder body are respectively arranged on both sides of the first main valve body, and through the connection design with the first main valve body, the pressure generated during the drilling process is flexibly adjusted. At the same time, the first blowout preventer and the second blowout preventer can effectively prevent the occurrence of blowout accidents in a fully enclosed state, ensuring the safety of drilling operations. The third cylinder body and the fourth cylinder are respectively located on both sides of the second main valve body, and through the connection design with the second main valve body, the pressure during the drilling process is further adjusted. The combined use of the third blowout preventer and the fourth blowout preventer in a semi-enclosed state can flexibly adjust the blowout prevention effect according to the actual drilling situation, which not only ensures the safety of drilling operations, but also improves operating efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the embodiment of the utility model, the following is a brief introduction to the drawings required for use in the embodiment of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work, and these are all within the protection scope of the utility model.

[0019] Figure 1 It is a three-dimensional structural diagram of an underbalanced drilling blowout prevention device;

[0020] Figure 2 It is a structural schematic diagram of a first valve body of an underbalanced drilling blowout prevention device;

[0021] Figure 3 It is a structural schematic diagram of a second valve body of an underbalanced drilling blowout prevention device;

[0022] Parts and numbers in the picture:

[0023] 110-first valve body, 111-first connecting plate, 112-first main valve body, 113-first connecting flange, 114-first cylinder body, 115-second cylinder body, 116-first blowout preventer, 117-second blowout preventer, 118-first cylinder flange, 119-second cylinder flange;

[0024] 120-second valve body, 121-second connecting plate, 122-second main valve body, 123-second connecting flange, 124-third cylinder body, 125-fourth cylinder body, 126-third blowout preventer, 127-fourth blowout preventer, 128-third cylinder flange, 129-fourth cylinder flange;

[0025] 131 - piston rod, 132 - accommodating chamber, 133 - piston chamber, 134 - piston body, 135 - slot, 136 - bump. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In the description of the utility model, it should be understood that the orientation or position relationship indicated by the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the utility model. Moreover, the terms "comprises", "includes" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprises..." do not exclude the presence of other identical elements in the process, method, article or device including the elements. If there is no conflict, the embodiments of the utility model and the various features in the embodiments can be combined with each other, all within the scope of protection of the utility model.

[0027] Example 1

[0028] See also Figure 1The embodiment of the utility model provides an underbalanced drilling blowout prevention device, including a first valve body 110 and a second valve body 120; a first connecting plate 111 and a second connecting plate 121 are provided on one side of the first valve body 110 and the second valve body 120; the first valve body 110 and the second valve body 120 are integrated with the first connecting plate 111 and the second connecting plate 121 respectively; the first valve body 110 and the second valve body 120 are used as a valve body after being connected, and are provided as a component to ensure the sealing effect and connection strength. A first connecting plate 111 and a second connecting plate 121 are provided on one side of the first valve body 110 and the second valve body 120 respectively, and they are integrated with the valve body through precise processing technology. This integrated design not only improves the overall strength of the device, but also effectively ensures its sealing performance. During the drilling process, even in the face of extreme conditions such as high pressure and high temperature, the device can maintain a stable working state and effectively prevent the occurrence of blowout accidents.

[0029] After the first valve body 110 and the second valve body 120 are connected, they will be used as a whole valve body. In order to ensure its sealing effect and connection strength, the designers use advanced materials and processes to make it a strong and durable component. In practical applications, this device can quickly respond to various abnormal situations and cut off the oil and gas channel in time, thereby effectively preventing the occurrence of blowouts.

[0030] See also Figure 2 The first valve body 110 includes a first cylinder body 114 and a second cylinder body 115; the first cylinder body 114 and the second cylinder body 115 are connected by a first main valve body 112; the first cylinder body 114 and the second cylinder body 115 are respectively arranged on both sides of the first main valve body 112 and are connected to the first main valve body 112; the first cylinder body 114 and the second cylinder body 115 are respectively provided with a first spray preventer 116 and a second spray preventer 117; the first spray preventer 116 and the second spray preventer 117 are combined to form a fully enclosed spray preventer.

[0031] The first valve body 110, as a key component of the entire system, mainly includes a first cylinder body 114 and a second cylinder body 115, which are tightly connected through the first main valve body 112. This design not only ensures the stability of the structure, but also improves the overall performance of the valve body. The first cylinder body 114 and the second cylinder body 115 are arranged on both sides of the first main valve body 112, and they have good connectivity with the first main valve body 112. This layout enables the cylinder body to effectively transmit gas or liquid, while ensuring the smoothness inside the valve body.

[0032] Furthermore, the first cylinder body 114 and the second cylinder body 115 are respectively provided with a first spray-proof member 116 and a second spray-proof member 117. The two spray-proof members are combined to form a fully enclosed spray-proof member, which effectively prevents the leakage of gas or liquid. This design improves the safety of the valve body and ensures the stability of the system operation.

[0033] In addition, the design of the first spray guard 116 and the second spray guard 117 also fully considers the use environment and use requirements. They are made of wear-resistant and corrosion-resistant materials and can operate stably for a long time in harsh environments. At the same time, the shape and size of the spray guard are also accurately calculated to ensure that it can fit closely to the inner wall of the cylinder body, thereby achieving a better sealing effect.

[0034] See also Figure 3 , the second valve body 120 includes a third cylinder body 124 and a fourth cylinder body 125; the third cylinder body 124 and the fourth cylinder body 125 are connected by the second main valve body 122; the first cylinder body 114 and the second cylinder body 115 are respectively arranged on both sides of the second main valve body 122 and communicated with the second main valve body 122; the third cylinder body 124 and the fourth cylinder body 125 are respectively provided with a third spray-out preventer 126 and a fourth spray-out preventer 127; the third spray-out preventer 126 and the fourth spray-out preventer 127 are combined to form a semi-enclosed spray-out preventer; the first main valve body 112 and the second main valve body 122 are connected. A through hole is provided in the middle of the combined semi-enclosed spray-out preventer; the shape of the through hole is circular, rectangular or elliptical.

[0035] Specifically, the second valve body 120 mainly includes a third cylinder body 124 and a fourth cylinder body 125, which are firmly connected through the second main valve body 122 to form a unified whole that can work together. The first cylinder body 114 and the second cylinder body 115 are respectively arranged on both sides of the second main valve body 122, and maintain good connectivity with the second main valve body 122. This design not only ensures the smooth flow of air in the valve system, but also provides strong support for the subsequent anti-blowout function.

[0036] See also Figure 3 Furthermore, a third blowout preventer 126 and a fourth blowout preventer 127 are respectively disposed in the third cylinder body 124 and the fourth cylinder body 125. The two blowout preventers are structurally related to each other and are combined to form a semi-enclosed blowout preventer. This semi-enclosed design can not only effectively prevent gas leakage in the valve system, but also adjust the opening and closing degree of the blowout preventer according to actual needs, thereby achieving precise control of the gas flow.

[0037] In addition, the first main valve body 112 and the second main valve body 122 are also connected. This design enables the two main valve bodies to work together to jointly adjust and control the flow of gas. When the valve system is running, the first main valve body 112 and the second main valve body 122 can adjust the degree of opening according to actual needs, thereby achieving precise adjustment of gas flow and pressure.

[0038] See also Figure 2 and Figure 3 Furthermore, by setting up fully enclosed and semi-enclosed blowout preventers, the underbalanced drilling blowout prevention device has demonstrated excellent performance and effects. First of all, the application of fully enclosed blowout preventers plays a vital role in preventing blowout accidents. During the drilling process, when encountering extreme conditions such as high pressure and high temperature, the fully enclosed blowout preventers can respond quickly, effectively cut off the oil and gas channels, and prevent oil and gas leakage, thereby avoiding the occurrence of blowout accidents. This design not only improves the safety of drilling operations, but also reduces the potential risks to the environment and personnel. Secondly, the design of semi-enclosed blowout preventers gives the device more flexible application scenarios. Semi-enclosed blowout preventers can adjust the degree of opening and closing according to the actual needs of drilling operations to achieve precise control of gas flow. In situations where it is necessary to control the gas flow rate or pressure, semi-enclosed blowout preventers can play an important role in ensuring the smooth progress of drilling operations.

[0039] Furthermore, the device also adopts a design in which the first main valve body 112 and the second main valve body 122 are connected, so that the two valve bodies can work together to jointly adjust and control the gas flow. This design not only improves the convenience of valve operation, but also enhances the stability and reliability of the entire system.

[0040] Example 2

[0041] See also Figure 2 or Figure 3 The embodiment of the utility model provides an underbalanced drilling blowout prevention device, wherein the first main valve body 112 and the second main valve body 122 are provided with cavities inside; the side walls of the first main valve body 112 and the second main valve body 122 are provided with through holes or openings. Flanges are provided outside the places where the through holes or openings are provided in the first main valve body 112 and the second main valve body 122. The first main valve body 112 and the second main valve body 122 are connected through the through holes or openings provided at both ends. The first main valve body 112 and the second main valve body 122, as the core components of the underbalanced drilling blowout prevention device, are designed with cavity structures inside. These cavities can not only store and regulate fluids, but also realize the smooth flow of fluids in the valve bodies through special structural designs. In addition, the design of the cavities also takes into account the pressure balance and stability of the fluid, ensuring that the device can still operate stably under complex working environments.

[0042] See also Figure 2 Furthermore, through holes or openings are provided on the side walls of the first main valve body 112 and the second main valve body 122. These through holes or openings not only provide a passage for the fluid to flow, but also enable the two main valve bodies to communicate with each other. The design of the through holes or openings takes into account the characteristics and needs of the fluid flow, ensuring that the fluid can flow smoothly from one main valve body to the other main valve body, thereby realizing the overall function of the device.

[0043] Furthermore, outside the through hole or opening, the first main valve body 112 and the second main valve body 122 are both equipped with flanges. As a connecting piece, the flange can not only enhance the connection strength between the valve bodies, but also ensure the sealing of the fluid. Through the tightening and sealing effect of the flange, the leakage of the fluid between the valve bodies can be effectively prevented, thereby ensuring the safety and reliability of the device. This connection mode enables the device to effectively prevent the occurrence of blowout accidents during underbalanced drilling. When the pressure in the well is abnormal, the device can respond quickly and balance the pressure inside and outside the well by adjusting the opening degree of the valve body, thereby avoiding the occurrence of blowout accidents.

[0044] See also Figure 2 , the first and second connecting flanges 113 and 123 are respectively provided at both ends of the first main valve body 112 and the second main valve body 122 after being connected. Flanges are provided at both ends of the main body for connecting with other equipment or pipelines. This design not only facilitates the installation and disassembly of the device, but also improves the flexibility and maintainability of the entire system. In practical applications, the underbalanced drilling blowout prevention device can be connected to drilling equipment, pipelines, etc. through flanges according to specific needs to form a complete drilling system. At the same time, the materials and processes of the first connecting flange 113 and the second connecting flange 123 have also been carefully selected and optimized to ensure that they have good sealing and durability. This can not only effectively prevent fluid leakage at the connection, but also extend the service life of the device and reduce maintenance costs.

[0045] In addition, the underbalanced drilling blowout prevention device can be adapted to drilling equipment or pipelines of different specifications and models by providing the first connecting flange 113 and the second connecting flange 123. This design improves the versatility and adaptability of the device, allowing it to be applied and promoted in a wider range.

[0046] See also Figure 2 and Figure 3The first spray-proof member 116 and the second spray-proof member 117 are connected at one end, and the other end is provided with a piston rod 131; the third spray-proof member 126 and the fourth spray-proof member 127 are connected at one end, and the other end is provided with a piston rod 131. The first cylinder body 114, the second cylinder body 115, the third cylinder body 124 and the fourth cylinder body 125 are provided with cavities inside; the cavities inside the first cylinder body 114, the second cylinder body 115, the third cylinder body 124 and the fourth cylinder body 125 are the accommodating cavities 132 of the first spray-proof member 116, the second spray-proof member 117, the third spray-proof member 126 and the fourth spray-proof member 127 respectively. The first cylinder body 114 and the second cylinder body 115 are provided with a first cylinder flange 118 and a second cylinder flange 119 at one end respectively; the third cylinder body 124 and the fourth cylinder body 125 are provided with a third cylinder flange 128 and a fourth cylinder flange 129 at one end respectively. The piston rods 131 disposed in the first cylinder body 114, the second cylinder body 115, the third cylinder body 124 and the fourth cylinder body 125 all extend to the inside of the first cylinder flange 118, the second cylinder flange 119, the third cylinder flange 128 and the fourth cylinder flange 129. The first cylinder body 114, the second cylinder body 115, the third cylinder body 124 and the fourth cylinder body 125 all have piston cavities 133 disposed therein; the piston cavities 133 are provided with piston bodies 134; the cylinder rods are disposed in the piston bodies 134; the piston bodies 134 are adapted to the piston cavities 133. A slot 135 is provided at one end of the first spray preventer 116, the second spray preventer 117, the third spray preventer 126 and the fourth spray preventer 127 connected to the piston rod 131; a convex block 136 adapted to the slot 135 is provided at one end of the piston rod 131 connected to the first spray preventer 116, the second spray preventer 117, the third spray preventer 126 and the fourth spray preventer 127.

[0047] Furthermore, the design of the spray-proof member adopts a combination of the first spray-proof member 116 and the second spray-proof member 117 and the third spray-proof member 126 and the fourth spray-proof member 127, which are connected at one end and are provided with a piston rod 131 at the other end. This design enables the spray-proof member to form a stable structure when in operation, and realizes its spray-proof function through the telescopic action of the piston rod 131.

[0048] See also Figure 2The cavity provided inside the cylinder body provides a space for the blowout preventer, so that the blowout preventer can work smoothly in the cylinder body. At the same time, the flange design at one end of the cylinder body not only provides a connection interface for the cylinder body, but also provides a channel for the extension of the piston rod 131, so that the piston rod 131 can smoothly enter and exit the cylinder body to complete its working cycle. The matching design of the piston body 134 and the piston cavity 133 ensures the stable movement of the piston body 134 in the cylinder body. When the piston body 134 moves in the cylinder body, it drives the piston rod 131 to expand and contract, thereby driving the blowout preventer to perform corresponding actions. The connection method of the blowout preventer and the piston rod 131 adopts the matching design of the card slot 135 and the protrusion 136. This design not only ensures the stable connection between the blowout preventer and the piston rod 131, but also enables the blowout preventer to perform corresponding blowout prevention operations as the piston rod 131 expands and contracts.

[0049] See also Figure 3 The piston rod 131 is connected to an external control device for controlling the extension and retraction of the piston rod 131 through the first cylinder flange 118, the second cylinder flange 119, the third cylinder flange 128 and the fourth cylinder flange 129. The piston rod 131 drives the piston rod 131 to extend and retract in the piston cavity 133 based on the piston body 134 through an external control device, thereby controlling the opening or closing of the blowout preventer.

[0050] Example 3

[0051] See also Figure 1 , the embodiment of the utility model provides an underbalanced drilling blowout prevention device. Through the above design, the underbalanced drilling blowout prevention device shows significant advantages in ensuring the safety of the drilling process and preventing blowout accidents. The through hole or opening design between the first main valve body 112 and the second main valve body 122 ensures the smooth flow of the fluid and effectively realizes the connection between the two main valve bodies, thereby ensuring the overall function of the device. At the same time, the setting of the flange not only enhances the connection strength between the valve bodies, but also ensures the sealing of the fluid, effectively prevents fluid leakage, and improves the safety and reliability of the device.

[0052] In addition, by providing the first connecting flange 113 and the second connecting flange 123, the device can be conveniently connected to other equipment or pipelines, thereby improving the flexibility and maintainability of the system. This design enables the device to adapt to drilling equipment or pipelines of different specifications and models, thereby improving its versatility and adaptability and broadening its application range.

[0053] See also Figure 2 or Figure 3Furthermore, in the design of the blowout preventer, the combination of the first blowout preventer 116, the second blowout preventer 117, the third blowout preventer 126 and the fourth blowout preventer 127, and the cooperation between the piston rod 131 and the cylinder body, make the device perform well in blowout prevention. The matching design of the piston body 134 and the piston chamber 133 ensures the stable movement of the piston rod 131, thereby driving the blowout preventer to perform effective blowout prevention operations. At the same time, the matching connection mode of the slot 135 and the bump 136 ensures the stable connection between the blowout preventer and the piston rod 131, and improves the reliability and durability of the device. The underbalanced drilling blowout prevention device effectively solves the blowout problem that may occur during underbalanced drilling through its unique design and reasonable structural layout. Its simple and effective connection mode, flexible connection mode and reliable blowout prevention design make the device play an important role in ensuring drilling safety and improving drilling efficiency.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the utility model.

Claims

1. An underbalanced drilling blowout prevention device, characterized in that: The valve body comprises a first valve body (110) and a second valve body (120); a first connecting plate (111) and a second connecting plate (121) are provided on one side of the first valve body (110) and the second valve body (120); the first valve body (110) and the second valve body (120) are respectively integrated with the first connecting plate (111) and the second connecting plate (121); The first valve body (110) comprises a first main valve body (112) connected to a first cylinder body (114) and a second cylinder body (115); the first cylinder body (114) and the second cylinder body (115) are respectively arranged on both sides of the first main valve body (112) and are in communication with the first main valve body (112); a first blowout preventer (116) and a second blowout preventer (117) are respectively arranged in the first cylinder body (114) and the second cylinder body (115); the first blowout preventer (116) and the second blowout preventer (117) are combined to form a fully enclosed blowout preventer; The second valve body (120) comprises a second main valve body (122) connected to a third cylinder body (124) and a fourth cylinder body (125); the first cylinder body (114) and the second cylinder body (115) are respectively arranged on both sides of the second main valve body (122) and are in communication with the second main valve body (122); a third blowout preventer (126) and a fourth blowout preventer (127) are respectively arranged in the third cylinder body (124) and the fourth cylinder body (125); the third blowout preventer (126) and the fourth blowout preventer (127) are combined to form a semi-enclosed blowout preventer; the first main valve body (112) and the second main valve body (122) are in communication with each other.

2. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: The first main valve body (112) and the second main valve body (122) are provided with cavities inside; the side walls of the first main valve body (112) and the second main valve body (122) are provided with through holes or openings; and the first main valve body (112) and the second main valve body (122) are provided with flanges outside the through holes or openings.

3. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: The first main valve body (112) and the second main valve body (122) are connected via through holes or openings provided at both ends.

4. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: A first connecting flange (113) and a second connecting flange (123) are respectively provided at both ends of the first main valve body (112) and the second main valve body (122) after they are connected.

5. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: The first blowout preventer (116) and the second blowout preventer (117) are connected at one end, and are both provided with a piston rod (131) at the other end; the third blowout preventer (126) and the fourth blowout preventer (127) are connected at one end, and are both provided with a piston rod (131) at the other end.

6. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: The first cylinder block (114), the second cylinder block (115), the third cylinder block (124) and the fourth cylinder block (125) are all provided with cavities therein; the cavities inside the first cylinder block (114), the second cylinder block (115), the third cylinder block (124) and the fourth cylinder block (125) are respectively accommodating cavities (132) of the first blowout preventer (116), the second blowout preventer (117), the third blowout preventer (126) and the fourth blowout preventer (127).

7. The underbalanced drilling blowout prevention device according to claim 1, characterized in that: A first cylinder flange (118) and a second cylinder flange (119) are respectively provided at one end of the first cylinder block (114) and the second cylinder block (115); a third cylinder flange (128) and a fourth cylinder flange (129) are respectively provided at one end of the third cylinder block (124) and the fourth cylinder block (125).

8. The underbalanced drilling blowout prevention device according to claim 7, characterized in that: The piston rods (131) arranged in the first cylinder body (114), the second cylinder body (115), the third cylinder body (124) and the fourth cylinder body (125) all extend into the interior of the first cylinder flange (118), the second cylinder flange (119), the third cylinder flange (128) and the fourth cylinder flange (129).

9. The underbalanced drilling blowout prevention device according to claim 7, characterized in that: The first cylinder body (114), the second cylinder body (115), the third cylinder body (124) and the fourth cylinder body (125) are each provided with a piston chamber (133); the piston chamber (133) is provided with a piston body (134) and a cylinder rod arranged in the piston body (134); the piston body (134) is adapted to the piston chamber (133).

10. The underbalanced drilling blowout prevention device according to claim 5, characterized in that: A clamping groove (135) is provided at one end of the first spray preventer (116), the second spray preventer (117), the third spray preventer (126) and the fourth spray preventer (127) connected to the piston rod (131); and a protrusion (136) adapted to the clamping groove (135) is provided at one end of the piston rod (131) connected to the first spray preventer (116), the second spray preventer (117), the third spray preventer (126) and the fourth spray preventer (127).

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